Off the Cliff

Now that the election is over there is now a lot of talk about the "Fiscal Cliff".  Discussion of this general subject actually goes back to at least to the "lame duck" congressional session that happened between the midterm elections of early November of 2010 and the new congress being seated in early 2011.  There has been some talk among politics junkies in the run up to the election that just took place on November 6, 2012.  But with the election out of the way this subject has moved to center stage.

So what is the Fiscal Cliff all about?  Well, the "scare" version of the story is that on January 1, 2013 all kinds of bad things will immediately happen causing the economy to crash causing the immediate end of all we hold dear. As you might imagine this is not an accurate characterization of the situation.  A more accurate characterization of the situation is that if no laws are changed between now and January 1 then federal taxes will go up somewhat and federal spending will go down somewhat.  So why is this the end of life as we know it?  Because the CBO (Congressional Budget Office) estimate is that this will stall the current anemic rate growth that the U.S. economy is now experiencing and throw us into a very mild recession.  Do we know for sure this is going to happen?  No!  It's just a best guess by a usually reliable source.

So, assuming politics in our nation's capital continues to gridlock, what actually happens?  Several things:

• The Bush tax cuts expire.  This will cause tax rates to be raised on pretty much everybody.  If you currently pay income taxes, those taxes will likely be higher.
• The Obama Social Security withholding rates go back up to the rates they were a few years ago.  This means that an additional two percent of most people's salary will be withheld.
• The "sequester" will kick in.  The Defense Department budget will be cut by $55 billion per year.  Funding for "non-defense discretionary spending" will be cut by $55 billion per year.  These are characterized as "draconian" by the people who passed the bill that causes these cuts.

These are the major provisions.  There are also a whole bunch of provisions that have less impact or apply only to small groups of people.  It is also important to realize that the Fiscal Cliff is not a single event.  Provisions of several bills expire at the end of 2012.  Several other bills have provisions that take effect in 2013.  They all get lumped together because they all affect either taxes or spending and they all take effect within a day or two of each other.

Finally, there is a theoretically unrelated event that will affect the federal budget that will happen at roughly the same time and often gets lumped in with everything else.  The U.S. has a "debt ceiling" law.  The federal debt is only allowed to raise to a certain level.  We are near that level.  There are various tricks and gimmicks that can be used to keep things going once the limit is reached.  But this trickery will only work for a short period of time, a few months.  The best current estimate is that the debt ceiling needs to be raised by February 2013.  There was a big fight the last time the debt ceiling needed to be raised.  There is no reason to think that this time around will be any different.  Many people have suggested that a debt ceiling increase be rolled into the same legislative package that would address the fiscal cliff.

So how did we get here?  It actually goes back to the early part of the Bush '43 Administration.  They wanted to do a big tax cut.  But whenever a tax cut is under serious consideration the CBO does an analysis of the impact over a 20 year time horizon.  Had the CBO done this the number would have been truly scary and it would have been harder for the bill to pass.  So the Bush tax cut was made "temporary".  It would expire in 2010.  Since taxes and, therefore, revenues would revert to the old amounts, the cost of the tax cut was way less scary and the bill was passed and was signed into law.  This worked so well that the Bush Administration pulled the same trick with s second tax cut they put through a couple of years later.  They also made it expire in 2010.  Now notice that 2010 is after the end of a two term Bush Administration.  It becomes someone else's problem.  And the cynical calculation was that the tax cut would never actually get repealed so the Administration got to have their cake and eat it too.  So far the prediction is working out.  A deal was done in the 2010 "lame duck" session to extend all provisions of both tax cuts for two more years.  So now they expire at the end of 2012.

When the Obama Administration came in they were faced with an economy that was truly a disaster.  Their first response was to pass a "stimulus" bill.  One of the provisions of this bill was a "temporary" reduction in Social Security withholding.  Normally 6.2% of an employee's salary is withheld for Social Security.  This is matched by the employer, except that self employed people have to pay the "employer" part too.  The "stim" reduced the employee amount to 4.2%.  This saved an individual making $50,000 per year $1,000.   As part of the deal that was made in the 2010 lame duck this provision was extended for 2 years so it expires in 2012 now too.

As a result of a political deal made a couple of years ago a "super committee" consisting of equal numbers of Democrats and Republicans and equal numbers of Senators and Representatives was formed.  To encourage them to come to a bipartisan deficit reduction deal a provision in the enabling legislation was included that said if they failed then starting in 2013 "draconian" (that was the design objective) cuts would be automatically mandated.  To spur on Republicans one of the cuts was $55 billion per year to the Defense budget.  To spur on Democrats the other cut was $55 Billion per year to "non-defense discretionary" programs.  What is in and out of this latter category is spelled out but it is complicated.  It's things like the NASA, Education, etc.  Social Security and Medicare were specifically exempted.  Needless to say, the super committee failed so the cuts are scheduled to go into effect if something is not done right away.

I have left out a lot of detail and I'm sure I have put most of you to sleep anyhow.  So let's just move on to what should be done.  We are now living in a political world at the federal level where everything is pushed to the limit so what should be minor or routine actions are blocked or delayed to the last minute and beyond.  If we had a functioning political system many of the components of the fiscal cliff would have long since been taken care of.  I lay almost 100% of the blame for this brinkmanship on the doorstep of the Republicans.

As a simple example, they forced a confrontation the last time the debt ceiling need to be raised.  This has historically been a routine activity.  There is usually some posturing but neither side does anything to stop the ceiling from being raised in a timely and predictable manner.  The last time around the Republicans brought the entire country to within hours of a total default of the government.  And that was after the Treasury pulled every trick and gimmick that anyone could think of to stave off what would normally have been the default date.  I could cite several other examples of Republican brinkmanship.  But if you don't want to agree with my characterization of the "debt debacle" then you aren't going to buy my analysis of the other events.  And, if you agree with my "debt debacle" analysis, then you can take my word for it that the other events are there and happened too.

So it is important to recognize that we have not only a "fiscal cliff" problem but we also have a Republican intransigence problem.  If we don't do something about both of them we don't make any real progress.  So what should be done?

Option 1 is to do what the Republicans say they want.  That would be to continue all the tax cuts (the Bush tax cuts, the Obama tax cuts, and the other tax provisions I haven't gone into).  They would also repeal and replace the "sequester".  They would make no cuts to the Defense budget.  Instead they would make very large cuts to "non-defense discretionary" and additional cuts to Social Security, Medicare, and Medicaid.  That is what they would do as best I can make it out.  They have not been very specific.

Option 2 is to do what President Obama wants to do.  He too has been pretty vague.  He would increase taxes on people making more than $250,000 per year.  He would preserve all the tax cuts for people making less.  As far as I can tell, he would leave the sequester in place.  This is good as far as it goes.  I am all in favor of the increase in taxes on rich people.  The problem is that it does not raise enough money.  I think we should raise taxes on the wealthy anyhow on fairness grounds.

Option 3 is to go off the cliff.  Let everything expire or go into effect.

Before continuing, let me state the obvious.  All of these pure positions are seriously flawed.  It is a bad idea to do any of them in their purest simplest form.  But they give us a starting point for discussion.  So let's discuss.

Option 1 is the most ridiculous.  The oratorical way the Republicans square the circle on this proposal is they offer to close loopholes in the tax code.  I am all in favor of this as a general principle but the devil is in the details.  And so far the Republicans have provided no details.  Well that's not completely true.  One Republican or another has taken pretty much all the big loopholes off the table.  My idea of "low hanging fruit" is various loopholes that favor the Oil industry.  Democrats have put together bills that close one or more of these loopholes.  None of these efforts has garnered a single Republican vote.  Two big loopholes that affect individuals are deductions for education expenses and mortgage expenses.  Various Republicans have taken both of these off the table.  There is the "carried interest" loophole.  This allows Hedge Fund managers to treat their multimillion dollar bonuses as Capital Gaines taxed at 15% rather than as ordinary income taxed at 35%.  Republicans have shot down the idea of closing the carried interest loophole.

In fact, you can find various Republicans taking all the big loopholes, corporate and individual, off the table at one time or other.  And no Republican has publicly supported eliminating a single specific loophole.  I am absolutely convinced that had Mitt Romney won the election and succeeded in getting his tax and budget programs enacted into law then no loopholes would have been closed, defense spending would have gone up, tax rates might have been cut, discretionary spending and entitlements would have been cut, and the deficit would have grown enormously.  That's what history says Republicans do when they get into the White House.

Option 2 is better but not by a lot.  The President has been short on detail in public.  As I have indicated above, raising rates on high income people is a good idea but it only solves a small part of the problem.  Apparently the President tentatively agreed to a package that included entitlement cuts (styled as "reforms") and cuts to discretionary programs.  But we don't know the details.  If the Republicans actually came up with some loopholes to close, and they were reasonable loopholes, I'm sure the President would go along with them.  Besides the ones listed above, there is another loophole I would like to see closed.  I would like for mortgage interest to be only deductible on a singe primary residence, as in you would have to live in the house for it to be deductible.  This would not bring in a lot of money but I still think its a good idea.

Now lets talk about options 3.  Actually, I want to talk about two variants.  Option 3a is the "limited" version.  We let everything go into effect.  That defines a new base case.  Then, after the new congress goes into session in early January, we enact legislation reversing or modifying the components we don't like.  This is the version advocated by Lawrence O'Donnell of MSNBC, for instance.  Why would we want to do this?  In a word (actually two) Grover Norquist.  Norquist put together a "no tax increases, ever" pledge and got almost all Republicans to sign it.  Increasing the tax rate on rich people counts as a violation of the pledge and would result in bad things happening to the Republican in question, if the past is any guide.  Enacting tax increases on rich people (i.e. the Obama plan) violates the pledge if it is done before January 1.  But after January 1 all those higher rates have already gone into effect.  So leaving the rate high on rich people is not a violation of the pledge.  And cutting the rates on non-rich people is fine and dandy.  Finally, if the new laws are passed and put into effect in the first month or two of 2013 the damage to the economy is tiny.  And many provisions can be made retroactive to January 1, causing even less harm to the economy.

The other version, option 3b, is to let the various provisions expire or go into effect and then do nothing.  This is supposed to be very bad for the economy.  But it might not be.  I cite the example of the first couple of years of the Reagan Administration.  Reagan fired the Air Traffic Controllers in a labor dispute.  The Fed drove up interest rates.  These, combined with some other actions, drove the economy into recession.  But it was a short sharp recession.  The economic problem at the time was a wage/price spiral that resulted in high inflation.  The recession cured the inflation and within two years the economy started growing robustly.

The Republican view is that the economy is doing poorly for two reasons.  First, the deficit is too high.  Second, there is a lot of economic uncertainty.  Option 3b attacks both of these issues.  It would cut the deficit  by more than in half in the short run and put us on track toward a balanced budget in the long run.  That's what the Republicans say they want.  Since this plan requires no new legislation is it definitely feasible in this "gridlock" political environment.  So uncertainty is removed.  People may be unhappy with the higher taxes but they know what the future looks like and can plan accordingly.

Large U.S. corporations are literally sitting on more than a Trillion dollars of cash.  If, due to the certainty of the budget and tax situation, they start spending this pile of cash then the economy could take off and quickly.  The CBO analysis of this option assumes there will be no change in corporate behavior and that individuals will cut back on their spending because they will have less disposable income.  But if the economy picks up due to higher corporate investment then this will put money directly into the pockets of people hired by these corporations.  Their income will go up so their spending will go up.  If the economy picks up in general then the income of the employees that are not directly involved in this increased corporate spending may well see their income go up more than enough to compensate for their higher tax load.  So we could easily see spending rise rather than dip and the economy growing rather than shrinking.

So option 3b may not be as bad as the CBO estimates.  But let's say the CBO is right.  Everyone will adjust.  So I predict a short mild recession.  After we exit from the recession we have a federal government that is on a sound and sustainable course.  So growth should be robust and sustained.  So even the bad version of options 3b is not so bad.

I find it very unlikely that either options 1 or 2 will happen.  It is possible that some blend of options 1 and 2 will come out of a genuine effort by the Republicans to compromise.  But it is very hard to imagine such a deal coming together quickly enough to be implemented before the end of the year.  So I see option 3 as what we will see.  And I don't see it as all that scary an option.  So what will we actually see, option 3a or option 3b?  I actually favor some version that is much closer to 3b than 3a.  I have skipped over a bunch of details when outlining the situation.  And, while I am comfortable about all of the major provisions that I outlined above, there are several minor provisions that I think need addressing.

One is the AMT, Alternative Minimum Tax.  This was a good idea when it was first enacted.  It was designed to close some loopholes used only by the rich.  But the provisions were not indexed.  As inflation has worked its magic more and more middle class people, people not intended as targets of the AMT provisions are effected.  Congress had dealt with this by enacting a series of annual AMT "patch" laws.  But the AMT needs to be fixed or repealed.  The problem is a political one.  A permanent AMT fix is scored by the CBO as a big tax cut as the CBO is forced every year to assume AMT is part of the baseline and, since it hits a lot of people, it theoretically raises a lot of revenue.  So the political problem is getting beat up about the high theoretical cost of fixing it.

Another problem is the "doc fix" to Medicare.  A few years ago it became obvious that doctors wouldn't take Medicare patients because the compensation rate was too low.  So the rate was raised, again temporarily, by 27%.  It needs to be permanently raised.  Again, on one has wanted to take the political hit for "blowing up the medicare budget" that a permanent fix would entail.

I have mentioned the debt limit above.  It needs to be raised.

The implementation of the "sequester" is a robotic "cut everything by the same amount".  I think it would be healthy to cut the Defense budget by $55 Billion a year.  But I would like a more intelligent approach to how the money is cut.  Barney Frank has suggested we can scale back our overseas commitments, especially troops in Europe and Japan, by a lot safely.  I agree.  This also cuts the money shipped over seas, where it doesn't help our domestic economy much.  There are weapons systems (e.g. tanks) that can be cut and bases that can be closed.  The money is there.

I am less happy about the "non-defense discretionary" cuts.  But if they are the price for the rest of the package I can live with them.  But again the "cut everything by the same amount" rule needs to be replaced with cuts that total to the same amount but are applied more intelligently.  Personally, I would like to take a big whack out of farm subsidies.  Almost all of the money goes to large corporate farms.  And, at the other end, I see no reason to subsidize small hobby farms.  Most farms that are small enough to look like a traditional family farm are actually hobby farms.  The group in the middle, relatively small farms that do support the rural lifestyle, are too hard a target to hit.  And a lot of them are already in some commodity that is not part of the farm subsidy program.  The only parts of the system that look like they might be a good investment to me are the extension service and research programs at "ag" colleges.  I don't know where the Department of Homeland Security fits in all this.  But I think there is more "waste, fraud, and inefficiency" in this department than in the Department of Defense, normally the "waste, fraud, and inefficiency" poster child.  I think a big whack can be taken out of the Homeland Security budget and, if done intelligently, would result in an increase in the security of the homeland.

There are numerous fixes that should be made to other items affected by the fiscal cliff.  But you have to ask yourself:  Are these fixes more or less likely to happen if we avoid going off the cliff?  I find it extremely hard to believe that they will be approached in an intelligent way if some grand bargain is made and going off the cliff is avoided.

So let's all go off the cliff.  It should be a hell of a ride. 

FCC Robocall Challenge

The FCC is running a contest called "FCC Robocall Challenge".  Details can be found at the following location:  http://robocall.challenge.gov/.  I have blogged about robocalls before.  See:  http://sigma5.blogspot.com/2012/02/rachel-from-cardholder-services.html for details.  So this subject is near and dear to my heart.  I think the FCC is slightly misguided.  They think the winner should come up with a solution, presumably a gadget, that "should block robocalls".  I think a proper solution consists of a number of components.  Some of these components would be hardware.  But other components would be processes or procedures.  Here's my solution:
 
Telco component

All telcos (anyone providing dial tone and access to the international telephone network) must provide the following service, implemented by a code, to their customers.  Someone on the contest web site suggested using “*111”.  I will leave it to the experts to decide what actual code would be used.  But when a customer receives an inappropriate call (e.g. a robocall) the customer will enter the code on his telephone keypad while the call is in progress.  This will cause the telco to record and retain certain information about the call.  Entering the code will also cause the call to be flagged as a “logged” call.  The customer will also be able to enter the code up to five minutes after the call ends in normal circumstances.  The window will expire immediately if the customer has not logged the call before making an outgoing call.  Also, if a new call comes in within less than five minutes, the window will expire immediately if the customer does not enter the code to flag the old call as a "logged" call before connecting to receive the new call.

Telcos will maintain the information on logged calls for a minimum of a week (7 days).  Then, if the customer “registers” the call within the one week period, the information will be retained for whatever period is appropriate.  Once the information is transferred to e.g. an FCC database it can be deleted from the telco system.

The telco will collect and retain the following information when the call is logged:
- Nominal caller ID of the source.
- True source of the call.
- Nominal caller ID of the destination (customer).
- True destination of the call.
- Call start date/time.
- Call end date/time or call duration (Experts can decide which).

Note:  A telephone call is a two way process.  To work both the true source and the true destination must be known to the telephone system.  This is the information that will be collected as the “true source” and “true destination”.

Note:  Crime TV shows make reference to “LUDs”.  If “LUDs” are a standard part of telephone infrastructure and the information in a LUD is equivalent to the information listed above then collecting a LUD for the call meets my requirements and no new special record type will be needed.

Customer component

This component is optional.  But, if provided, it must operate as described.

First let’s consider a standard “land line”.  For the moment let’s also assume that the line has a customer provided answering machine.  The new component can be thought of as an “enhanced” answering machine that would replace the standard answering machine.  The enhanced answering machine would require an Internet connection (e.g. Ethernet or WiFi connection with an IP address assigned to the device).

The enhanced answering machine would process calls that “go over to the answering machine” in the usual manner.  But the enhanced answering machine would also speculatively record the first five minutes of all “live” incoming calls too.  The telephone system started going digital in the 1960s.  At that time a standard was established that converted the audio component of a conversation to a digital format.  The digital data consisted of 56,000 bits of data per second of conversation.  This is equivalent to 7,000 bytes of data.  The enhanced answering machine will record the data in a standard format specified by experts that has a fidelity equivalent to the old 56,000 bits per second standard.  Assuming no compression, a five minute recording would consume 2.1 million bytes of storage.  This is well within the capability of inexpensive computer technology available today.  Multi-Gigabyte thumb drives are readily available for about $10.  If the standard included compression or other techniques, or the call lasted less than five minutes, the file could end up being much smaller.  And the file should be encrypted using standard techniques for privacy reasons.

So the enhanced answering machine would speculatively record all incoming calls.  If the call was not logged (see the above rules) then the recording would be silently discarded.  Logged calls would be retained and a standard technique would be specified by the experts for transferring the recording to an Internet capable device (e.g. a computer).  Vendors would be required to provide a minimum capability to record and retain one logged call at a time.  The recording could be silently discarded after a week at the discretion of the device maker.  The device maker could optionally provide the capability to retain more than one recording or retain it for longer than a week.  The device maker would just have to spell out the actual capabilities over and above the minimum in the documentation for the device.

What is important here is the capability, not the specific hardware implementation.  An enhanced answering machine is certainly an easy way to understand the required capability and feasible way to implement the capability in the case of a standard land line.  But a lot of people now use smart phones.  All the required capability can be implemented in a high end smart phone using software without requiring an external box or other supplemental hardware.  Many people have an “answering machine” service provided by their telco using equipment not located on the customer premises.  The telco could enhance their ”answering machine” service offering to provide equivalent capabilities.  Or they could choose to not provide the additional capability.  The only thing I require is that they be clear with their customers as to whether their “answering machine” service provides the described enhanced capability or not.  If their offering did not provide the enhanced capability then customers would be free to decide whether they wanted to continue the telco provided service knowing that message recording would not be available to them or to instead go ahead and acquire an enhanced answering machine device to replace the telco offered service.

The registration process

We now have much more information available than before.  We will now always have the logged information for all flagged calls.  Where the additional capability exists (e.g. the customer has installed an enhanced answering machine) we also have a recording of the first five minutes of the incoming call.

A change would be made to the current process for registering a complaint with the FCC.  Currently this is done through the FCC web site.  The new process would be done through a telco web site or through a free down loadable app for smart phones or free app provided by telcos to their customers that would run on an Internet attached customer PC.

The telco would validate the identity of the customer e.g. by a log in process to their web site.  In the case of a smart phone app, validation is automatic because the app runs on the customer smart phone and would only use data available on that smart phone.  The registration/validation process should be simple in the case of a web site.  And customers could log complaints to the FCC about their telco’s process if they did not like it.

Using the telco web site, smart phone app, etc. the customer would be able to see his recent logged calls.  He would then be able to select one or more to “register” as a complaint with the FCC.  The complaint information would be passed through to the FCC from the telco web site, app, etc.  The detailed specifications I leave to experts.  But I envision an implementation where the telco web site "front ends" for the FCC web site.  The telco web site would be responsible for a "pass through" capability to pass the logged data and, if present, recording file, along to the FCC web site.  The FCC would incorporate the logged data and, where it exists, the recording into the complaint.  This is why the smart answering machine would need Internet access.  The "Internet access" for this device could be restricted to the customer’s local LAN.  The PC could pull the file from the smart answering machine and upload it into the complaint package.  In the case of a smart phone or telco provided enhanced answering machine service the appropriate procedure would be used to include the recording in the complaint package.  Timestamps would be used to match the correct recording to a logged call record.

FCC process

The FCC would now have much more information and much more reliable information for evaluating complaints.  The FCC project is designed only to address inappropriate robocalls.  So let me proceed along that path for a while.  It is probably impossible to automatically identify robocalls.  My recommendation is to not try to do it automatically.  Use volunteers instead.  The same registration process for the telco web site would be use to register volunteers with the FCC.  The volunteers would listen to the recordings and evaluate manually whether the complaint was valid.  They would not know the identity of any of the parties involved.  All they would know was the type(s) of complaint alleged by the customer.  Multiple volunteers would evaluate each recording and a super majority would be required to validate the complaint.  The FCC would act accordingly in the case of a validated complaint.

Certainly this is a good process for dealing with robocalls but it is easily extended to handle other cases.  This is done by giving the customer some options for characterizing the problem when a complaint is registered.  One would be “robocall”.  But another big problem is with live operators making illegal marketing calls (i.e. violating the “do not call” list).

I suggest that a rule be implemented that required all robocalls to include the name and a "contact" phone number for the organization making the robocall.  The information must come in the first minute of the call.  Customers could complain that the caller was not doing this or that he was providing bogus information.  (It should be a serious crime to omit the information or provide bogus information).  The same information would be required for “live operator” calls if the customer requests it.  This permits a number of complaint categories:

- Company name omitted or bogus
- Contact phone number omitted or bogus.
- Contact number does not work (not answered or calls are not returned).
- Inappropriate contact (i.e. call not permitted by “do not call” exceptions).
- Illegal Robocall (marketing call rather than a e.g. "snow closure" informational call).
- Etc.

If the call contains misleading or bogus information the caller would first be gone after on this basis.  If the contact name and phone number is correct then complaints would be aggregated by who is making them and the “use many separate numbers to originate the call from” trick would no longer work.  This system would also catch spoofed “caller ID” numbers, which should be illegal, if it is not already.

Beyond the FCC

The FCC process for dealing with robocalls has been a failure from a customer perspective.  It is possible that the FCC, even with this new capability, would not do an adequate job.  So I recommend that individuals (or a class of individuals in a class action suit) be allowed to file a lawsuit in the situation where the FCC declines to prosecute.  I believe that robocallers do not want to find themselves in a court room where they will be judged by a jury of citizens.  This implied threat should allow the FCC to be much more effective than they currently are.  Violators know that they are pretty toothless now.

This system can also be expanded to cover situations beyond robocall and “do not call” problems.  An obvious example is harassing phone calls.  Here the information would not go to the FCC but to law enforcement or the court system.  In the worst case, the basic call information would be available.  In the best case, a recording of the first five minutes of the call would also be available.

Basic threats e.g. “husband threatening to beat wife” situations could be dealt with directly.  But other problems (e.g. “heavy breathing with caller not identified”) could also be addressed.  The same third party validation system would be employed.  This would filter out reverse harassment situations where the recipient is alleging harassment when none is actually present, at least not in the first five minutes of the call.

Analysis

Every indication is that the vast majority of robocalls originate from a small number of abusers.  The above system seems slow and cumbersome but it will yield results that will actually solve the problem.  It will take some time for the telcos to implement the logging process.  It will be some time before customers have enhanced answering machine capability in large numbers.  But it will get us to where we want to be in the end.

If the FCC contest yields what they say they are looking for (e.g. an inexpensive robocall filter device) it will be some time (years) before most customers have one.  Likely the device will cost more than the enhanced answering machine device that is part of my proposal.  So the aggregate cost of the FCC approach will be the same as or higher than the cost of my proposal and will probably take the same amount of time or longer to implement.

I see only one long term problem to my proposal.  If my proposal is successful then robocalls and other similar telephone related problems will plummet.  At that point the number of volunteer listeners will probably also plummet.  But the need for listeners will plummet too.  At that point it may be necessary to pay listeners to attract and maintain a sufficient number of them.  If we get to this point perhaps some fine or fee will be needed to provide the money to pay the volunteers.

Finally, there are some areas I have not addressed.  For instance:
- How is the volunteer pool managed (e.g. weeding out bad performers)?
- A lot can be done with just the registered complaints data, e.g. statistical analysis.
- Should the complaint database be published? (Of course!)  How?
- How to deal with legitimate but unpopular callers (e.g. ethical collection agencies).

Written Communication

I'm an old fart.  When I was a kid the standard and pretty much only form of written communication was a hand written letter.  Typewriters existed.  But most of them were manual (hit a key and a series of levers would cause a letter to thwap into the paper).  Electric typewriters existed.  Here it was like power brakes on a car.  You hit the key and electricity assisted the levers to thwap on the paper so you didn't have to hit the key so hard for the typewriter to work.  But typewriters were for the office.  Few homes had them.  My home didn't have one.

So people like me were expected to occasionally hand write a letter to grandma or whoever.  I was really bad at this for two reasons.  The first one was practical.  My handwriting was and still is horrible.  I was taught "Palmer" penmanship in school but it didn't take.  At some point I switched to printing rather than writing.  But my printing, while better, was also pretty unreadable.  The second problem was I was always stumped as to what to write.  I now know that banal is just fine.  Just natter on and everyone would be happy.  But I was not a good natterer and I just never even figured out that that was what you did.  So I was a bad boy.  I can't remember writing even one letter as a kid.  And just to give you an idea of how different that time was, a first class postage stamp was three cents.

In high school my mother insisted that I take typing.  This was an improvement in that at least what I wrote would be legible.  But I was also a terrible typist.  A typical person can learn to type 30 - 80 words per minute.  My top speed was about 15.  And I was very inaccurate.  If I tried to type even 15 words per minute I would make lots of mistakes.  I remember that in one speed test lasting 15 seconds I made 12 mistakes.  In spite of this my mother sent me off to college with a small typewriter, which was a good idea.

In terms of coming up with what to say, things got a little better.  I had to take a series of English classes as a Freshman.  After a couple of failed attempts to do something sensible I found that what worked for me was procrastination.  If I waited until I barely had time to finish the composition then batted out whatever came to mind, I could complete the assignment.  Surprisingly I got fairly good grades for these efforts.

Computers and I first met in college.  And I found that I finally was in an environment that worked for me.  I found I could quickly compose computer programs.  And the "keypunch" machines of the time were like typewriters.  Except there were tricks that allowed you to correct mistakes.  And 15 words per minute was no impediment.  While I was relatively quick, I wasn't quick enough to compose computer programs faster than I could type them in.  So I was in hog heaven.

For many years I assumed that my compositional efforts would be restricted to computer software and I was OK with that.  But technology marched on.  First the CRT came along.  CRT stands for Cathode Ray Tube.  It is actually just the picture tube part of an old fashioned TV.  But it came to be the nickname for a device consisting of a keyboard, CRT, and associated electronics.  You typed on the keyboard and characters appeared on the screen.  But now all you had to do was hit the "backspace" key to go back and correct errors.  This was an improvement but initially it was only practical for using with computer software.  So it became much easier for me to compose and update computer software but it was still impractical to apply these techniques to regular letters to regular people.

But an interesting thing happened as technology continued marching.  I could pretend to write a program but then instead of putting it into the computer I could just print it out.  Using this trick I could compose something like a letter.  And I did so.  I composed and printed a number of letters about some practice or project having to do with work and passed them along to the computer center manager.  He told me he liked them and found the information in them useful.  He encouraged me to write more of them.  This was the first time it occurred to me that I might have something to say.

Technology marched on and E-Mail evolved.  This was clearly a potential substitute for the hand written letter.  Initially it as only a little better than the "write a computer program that is really a letter and then print it out" system I had been using.  And E-Mail systems only allowed you to send a letter to someone who had a CRT that was hooked up to the same computer as your CRT.  So it was only good for sending E-Mail to other people who worked in the same building or perhaps the same company.  But eventually E-Mail systems started connecting to each other and finally through the Internet to anyone who had a computer.  And by this time lots of people had a computer.

I had finally arrived.  I could communicate via E-Mail.  I could type rather than write.  So the result was legible.  I had decided by this time that I had something to say.  Mostly it was about work or technical stuff but that beat having nothing to say at all.  I am still not that good at nattering but I am better than I used to be.  And E-Mail systems came with spell check. I have always been a bad speller.  Being a bad speller then adding a lot of typing mistakes on top makes for a pretty bad situation.  But it was as good as it was going to get for me.

But technology continued to march on.  E-Mail is now "so last year" or "last decade" or whatever.  (See, there is an entirely legitimate use for the much maligned "whatever").  The currently popular methods of communication are Facebook and Twitter.  I have neither a Facebook account nor a Twitter account.  To be a proper Facebook user you are supposed to post pictures and do all kinds of other stuff I am bad at.  Twitter is all about the famous "140 character limit".  A lot of people have found a lot of very good things to say in 140 characters.  And Twitter allows you to link to something like a picture, a blog post, or something else that doesn't fit into 140 characters.  But I am a long form kind of guy.  Most of the time I want to say something that will take a lot more than 140 characters to say.  Facebook is a great picture sharing service.  And Twitter is a great way to broadcast headlines.  But I am not very good at either of those things.  So I have been passed by.

But wait, it's worse.  Most people still have one or more E-Mail accounts.  So I can pretty much communicate to anyone I want by sending an E-Mail.  But I have noticed something.  A lot of people manage their E-Mail accounts using a smart phone.  Smart phones have sucky keyboards.  So people keep their responses short.  And I find that sometimes they don't scroll down or whatever (because it's hard to do on that small screen) and they miss part of what's in my message.  So I find that E-Mail is becoming more and more Twitterized.  It is becoming just another home for "headline" messages.

"What a world.  What a world."

BTW, that's what The Wicked Witch of the West said while she was melting in the 1939 MGM version of "The Wizard of Oz".

Education Reform

This post is about Kindergarten through High School education, generally referred to as K-12.  The U.S. has a reputation for providing more elite post-secondary (e.g. college and grad school) institutions than any other country in the world.  It also has a very good reputation for its non-elite schools in this category.  So the general consensus is that this category doesn't need fixing.  K-12, however, is a different matter.  This category has been argued over for generations and has been a political punching bag for at least a generation.  I have no special expertise in this area.  But that's not going to stop me from pitching my two cents in anyhow.

I am, of course, a consumer of this product.  I received my K-12 education in the U.S.  There are probably few people whose trajectory through this system is exactly typical.  Mine isn't completely typical but it's not very different and it is a common trajectory.  I was educated in a Parochial School run by the Roman Catholic parish where my parents attended church for my first 8 years.  Then I attended public schools for the last four years.  In my opinion I got a good education.  And I am in a position to personally compare the Parochial School experience with the Public School experience.  The comparison is very enlightening.

Parochial School was a "stick to basics", "no frills" experience.  The curriculum was completely standard except for the addition of a one hour religion class each day.  When I hit Public School I found I was well prepared.  I could read well.  My mathematics was up to snuff.  My social studies abilities and skills were up to snuff.  I can't say what kind of shape I would have been in had I attended Public School for those eight years but I see no reason to believe that it would have been much different.

But physically the experience was different from what I would have experienced in a Public School.  There were no shop classes.  There was no PE (Physical Education) classes.  There were no music classes.  I remember that one day a teacher brought in a Chemistry Set.  It was the kind a parent would buy for a child.  No particular use was made of this.  All of these types of amenities cost money.  You need a Gym and showers for PE.  My school had an auditorium but no showers.  You need musical instruments to do music.  My school had no musical instruments.  The school had no lab space suitable for biology or chemistry.  The physical plant of the school consisted of the aforementioned auditorium, class rooms, and a playground with a couple of basketball hoops and a few tether ball poles.  No other athletic equipment was provided.

But wait, there's more.  I do not remember attending a class with less than thirty other students.  One teacher was supposed to maintain discipline, teach all the classes, and provide whatever one-on-one attention students needed.  In short this school did a number of things that are supposed to be exactly the wrong way to educate students.  There were too many students in the class room.  There was little or no "enrichment" (e.g. music, shop, athletics).  But I got an excellent education anyhow.  And I was not an anomaly.  Many of my fellow students followed my same path.  They did a number of years in Parochial School, transitioned to Public School, and did just fine.  I was a typical exemplar of students turned out by Parochial School, not an outlier.

And this is generally true.  Parochial Schools have a very good reputation in the US.  It is so good that many Parochial Schools have a large percentage of their students coming from non-Catholic families.  Parochial Schools are the only alternative to a Public School option that is financially possible for many families.  Parochial Schools have a reputation for providing a high quality low cost option to the standard Public School option.  And they prove that a lot of the conventional wisdom about how to fix the public school system is bunk.

I certainly enjoyed my time in Public School and felt I got a good education there too.  But it is important to remember that this school district was in a well off suburban area.  The school system had and still has a very good reputation but it also has more money and a more stable social environment than many public school systems.

So if many of the standard nostrums for fixing the public school system are wrong then what's right?  Here I am very disappointed with what the Bill and Melinda Gates Foundation have come up with so far.  You can read a position paper from them here:  http://www.gatesfoundation.org/postsecondaryeducation/Documents/nextgenlearning.pdf.  I didn't think much of it.  It is  mishmash of jargon almost completely devoid of clear thinking and any kind of data driven foundation for what little it contains.

One of the ideas that the Gates Foundation and others push is Charter Schools.  Charter Schools have been around long enough so that if they did a substantially better job of educating kids we should see some clear data to support this.  But what little data I have seen indicates that Charter Schools perform about on a par with Public Schools.  Another is reducing class size.  This too has been tried a lot.  I have seen no strong evidence that this works particularly well either.  Another idea is technology in the classroom.  As a computer guy I should be all for this.  But again there is no strong evidence supporting the idea that this makes a big difference.

Parochial Schools are not much different than Charter Schools.  My Parochial School experience argues against expecting much from reduced class sizes or introducing a lot of technology.  It also argues against the great benefit of a richer experience (e.g. sports, music, labs,. etc.).  Now some of you may be about to argue that I have just contradicted myself.  If Charter Schools are a lot like Parochial Schools then they should be working well.  And they should.  But the data says they don't.  And I remember seeing a "60 Minutes" (I think it was 60 Minutes) episode where they talked to a Parochial School Principal.  She said she would not be able to do even as well (her school was rated noticeably better than the surrounding Public Schools) if she had to follow the same rules and regulations as the Public School administrators did.  So what do I think works?

One of the problems with most of the analysis of what's wrong stems from looking in the wrong places.  If you are not looking in the right places the answer to your question contains a high percentage of noise and little or no pattern will emerge.  I think the wrong things are being measured to try to find the success factors.  Here's my list of success factors:

1.  The most important thing is whether a kid comes to school willing and able to learn.  Key to this is whether the kid thinks it is important to learn.  And key to this is whether the parent(s) think education is important.
2.  If we have met the first criteria, the second criteria is a good teacher who is allowed to do her job the way she thinks it should be done.
3.  The school environment must be safe from violence and from bullying and other activities that discourage a kid that wants to learn from learning.
These are the keys.  Of lesser importance are:
*  A good and safe physical plant (e.g. no pealing paint, broken windows, lights that work, etc.)
*  Smaller classes.
*  A richer experience.
And so on.

Someone somewhere has succeeded in teaching whatever "unteachable" group you can think of.  It's not the native intelligence of the kid.  In most cases parents seek out these experiences once a program attains a good reputation.  And that is important.  Because if a kid has parents (or parent) that care how well the kid does in school then they keep on top of how the kid is doing.  This results in the kid being expected to learn.  If the kid fails the parent(s) get on him or her to improve.  In this environment most kids most of the time end up willing to learn.  And almost all kids are able to learn.  These "success story" situations also usually involve good teachers and a safe environment.  I think you can find successes that lack one or more of the remaining criteria.

How about this for an idea?  As far as I know it has never been tried.  Evaluate kids and pick out the under performing ones.  Then look at the home environment.  Look for kids with parents that are uninvolved or have low expectations.  Try to educate the parents to be better at motivating and monitoring their kids.  Then there are homes where the parents would like to do the right thing educationally by their kids.  But they can't due to poverty, language skills, violence, etc.  Here it would be nice to provide help.  But except in the language situation this should be a job for social services, not schools.  As far as I can tell low or non-existent educational attainment of parents (e.g. parental illiteracy) is not a factor. Kids of illiterate parents do very well even if the parents never learn to read.

With this as a foundation it is instructive to look at efforts to improve education.  Little or no effort is devoted to my most important item.  There have been many efforts devoted to item number two but they usually involve more not less interference with the teacher doing things the way she would prefer.  In fact there is a large industry dedicated to standards, tests, evaluations, etc., all of which have the effect of telling the teacher how to teach.  Efforts to address item number three are sporadic and not up to the task.  Instead most effort is devoted to the lower priority items or to items I didn't even list.

It is also important to pay attention to what ought not to be done.  One idea usually associated with liberals is to pass students whose work does not merit it.  I think this is a mistake.  If a kid is not doing fourth grade work or eighth grade work he should be flunked until he can demonstrate the proper proficiency.  Unqualified students provide a distraction to both teachers and other students.  In the long run they don't even do the kid any good.  For a short period of time his self esteem is left undamaged.  But society and the kid eventually figure out that the kid is not a high school graduate in terms of what he is capable of and things go rapidly down hill from there.

And there is the issue of focus.  The more things you try to do the less likely you are to do a good job of all of them.  I think schools and school districts should be focused completely on education.  In the same way that they should provide an honest evaluation of how educated a student is by not passing him along, they should not be responsible for public safety or caring for the needs of people with physical or mental problems.  If a kid is misbehaving then he should be kicked out of school and turned over to the juvenile justice or police system.  Let schools teach and let public safety organizations provide for the public safety.  Similarly, I am sympathetic to the plight of people with physical or mental handicaps.  But at some point they should become social service problems not problems to be solved by our educational systems.

Years ago the standard was to keep people with physical or mental handicaps out of sight.  This was wrong, particularly for people with mild handicaps.  The standard flipped over to "mainstreaming" everyone.  I believe this is an over reaction.  I think it is good to mainstream people with mild handicaps.  It's good for the individuals themselves.  It is also good for the other students and staff.  It broadens their experience base and makes them more tolerant, which is good.  But it is not the job of school systems to deal with all of these people, particularly with those with severe problems.  This means a line needs to be drawn.  How do you decide who is mild and who is severe?  I am not confident I have the right answer.  But I do have an answer.  How much does it cost to place and maintain a particular individual in a Public School environment.

I think you set a financial threshold.  My suggestion is six times.  This is a completely arbitrary line and it may be that some other cut off would work better.  But it is the one I have come up with.  If the additional cost is six or less times the cost of a normal student then the handicapped individual should be placed in school and become the responsibility of the school district.  If the expense will be higher then the responsibility should rest with social services.  If social services can come to an agreement with the school district and pay the school district whatever the additional cost over that of a normal student then it may be a good idea to place the individual in school.

And this is the usual "bright line" rule.  This may result in the school people and the social service people (or others) trying to game the system to get the individual over or under the threshold.  Bright line rules always result in these kinds of issues.  I am perfectly willing to entertain a "sliding degree of responsibility" where there is a sliding scale of financial and other responsibility for the individual.  But I think my idea is a good place to start the discussion from.

There is also an elephant in the room that I have not brought up yet.  That's politics.  Educational policy is a bigger political football than it has ever been before.  This is very bad for education.  It draws energy and money away from the current system.  In almost all cases more resources are better than fewer resources.  So whatever resources are eaten by the squabbling end up being taken away from where they are needed.  And if the fight gets hot enough a consensus may develop to starve the beast.  Certainly the time and effort that a good teacher spends dealing with paperwork, bureaucracy, and politics is time and efforts that can not be applied to teaching.  And good people don't like working in a politically charged atmosphere.  It's just not worth the aggravation.

Now let's look at Teach for America.  Teach for America is good intentioned.  It is designed to help solve a very real problem.  Our society depends heavily on what is generally called STEM, Science, Technology, Engineering, and Mathematics.  So our educational system needs to do STEM well.  But there is a large shortage of STEM qualified teachers.  And, as I said, this is a real problem.  Teach for America attempts to address this problem by finding STEM qualified individuals, running them through a fast "teaching boot camp" and putting them into the classroom.

It is better than nothing.  But it is a "paper it over" solution rather than an effort to address the problem directly.  The direct way to address the problem is to have teachers who are STEM qualified.  How do we do this?  Money!  If we paid teachers with STEM skills more money then we would find teachers getting STEM training and we would find STEM trained people getting teaching degrees.  But that would cost too much money.  So we have Teach for America.  The way you know that Teach for America is not the right solution is by looking at retention.  Do people who get in the program stay in teaching?  No!  Large numbers of them are gone after two years or less.  And remember the job market currently sucks.

I just don't believe that finding the right solutions to the education problem is that hard a problem.  So why aren't we well on the way to solving it?  Because the fundamental problem is money.  We need to spend more money and we need to spend it more effectively.  No one wants to spend what it would take to solve the problem so it becomes a big political football.  And in a highly politicized environment what money gets spent where becomes all the more important.  And those with the most political power, not those with the best ideas, tend to win the fights.  The overall result is that more and more money and effort is invested in making and enforcing rules, and in the kind of bureaucracy that grows up in a highly politicized environment.  This leaves less and less money to actually do what works.  And so things get worse and we start another round of political fighting that eventually makes things even worse.

Let me make a final observation on unions.  There is a large group of people invested in the idea that unions are evil and wasting lots of money and standing in the way of education reform.  In the current environment what are teachers supposed to do?  They are buffeted by every "trend du jour" and generally speaking no one cares what they think about anything.  In that environment a strong union with a mission to make teachers impossible to fire makes a lot of sense.  I think teachers unions have stood in the way of a lot of educational reform.  But it is hard to get angry at them.  There are a lot of others trying to mess up the educational system and harass teachers.  Perhaps if teachers didn't feel so much like the football in a Superbowl game they would be willing to be more flexible.

One thing Bill Gates has come to believe is that you can tell if a teacher is going to be a good teacher by seeing how they do in their first three years on the job.  If this is true then all you need to do is put in a "three year probation" rule.  If the teacher makes it through the first three years (assuming the evaluation procedure is a good one - not the teacher's responsibility) then it makes no sense to worry very much about how to get rid of teachers that have more than three years on the job.  They should be good teachers in almost all cases.  It is probably cheaper to carry the few "dead wood" teachers that make it past three years than it does to put in a lot of effort into a procedure for terminating experienced teachers.  And this would have a great benefit.  The many good teachers who made it past their three year probation could relax and focus on teaching for the rest of their carrier.  The morale boost would more than compensate for whatever it cost to keep the dead wood.

50 Years of Science - part 4

This is the fourth in a series.  The first one can be found at  http://sigma5.blogspot.com/2012/07/50-years-of-science-part-1.html. Taking the Isaac Asimov book "The Intelligent Man's Guide to the Physical Sciences" as my baseline for the state of science as it was when he wrote the book (1959 - 1960) I am examining what has changed since. For this post I am starting with the chapter Asimov titled "The Death of the Sun".

Again Asimov starts with a review of thought on the subject, starting with Aristotle.  He starts out with a general discussion of whether the sky as a whole is unchanging.  He notes several instances of changes in the sky that would have been visible to the naked eye and, therefore, noticeable to the ancients.  The Greeks either didn't notice them or decided to ignore the changes.  But other ancients did notice some of these changes.  This leads to a quite general discussion of several stellar phenomenon.  He then starts moving toward a discussion of our nearest star, the Sun.  As part of this discussion he introduces the Hertzsprung-Russell diagram and the concept of the "main sequence".

The reason for this is that these ideas form the basis for understanding how stars evolve.  This, in turn, allows us to predict the life history and eventual fate of stars.  In short, large stars burn brightly and don't last very long.  Small stars burn much more dimly but last a very long time.  Our Sun is in the middle.  It is in the middle in terms of how bright it is and also in terms of how long it will last.  The H-R diagram also allows us to predict how our Sun will age.

According to this analysis our Sun is middle aged and will stay that way for several more billions of years.  Then it will become a Red Giant, a very large, very cool star.  Asimov then relates recent (relative to 1960) developments.  Stars burn Hydrogen to make Helium.  But then they can burn Helium to make Carbon.  This chain can continue so that stars can create large amounts of Oxygen and Neon.  Asimov also reports that Magnesium, Silicon, and Iron can also be created in the heart of a star.  If a star explodes (e.g. in a Supernova) then these elements can be spread throughout space.  This was the start of solving the problem of where these other elements come from.  Only Hydrogen, Helium, and and a very small amount of Lithium are created in the Big Bang.  Of course it did not solve the mystery of where all the other elements came from.  It turns out this mechanism can not create any of the elements heavier than Iron.  Research that took place after Asimov's book came out suggests that the Supernova explosion itself creates the other elements.

Once most of the Hydrogen is burned the evolution of a star speeds up tremendously.  All the other stages happen very quickly compared to the billions of years the Hydrogen stage takes for a star the size of the Sun.  And once a star hits the Iron stage it quickly runs out of energy.  A star like the Sun goes from a Red Giant to a White Dwarf in the blink of an eye at that point.  Asimov then moves to the Chandrasekhar limit.  A star with the mass below the limit (1.4 times the mass of the Sun) will relatively gently settle into the role of a White Dwarf.  Those above the limit, however, explode as the Crab Nebula did.  This supernova explosion was observed in 1054.  But current estimates put the nebula between 5 and 8 thousand light years away.  That means the supernova actually occurred between 3,000 BC and 6,000 BC.  The best guess is that it exploded about 4.300 BC.

Asimov wraps the chapter up with the observation that White Dwarfs last tens of billions of years.  So the Sun will be a White Dwarf for much longer than it will look the way it currently does.

Missing from the discussion are Black Holes and Neutron Stars.  These existed at the time as theoretical speculation.  A few years after the book was published Astronomers concluded that Cygnus X-1, an X-ray source in the constellation Cygnus, was a black hole.  There still exists no direct observations of Black Holes.  But out understanding of them has continued to improve.  Many likely Black Holes are now known.  And there is a class of Black Holes whose existence was not even suspected at the time of Asimov's book.  Astronomers now believe that many galaxies, including our own Milky Way and our nearest large neighbor galaxy, Andromeda, contain supermassive Black Holes.  These Black Holes weigh in at millions to billions times the mass of our Sun.  It is early days in terms of our understanding of these entities.  But they seem closely bound up in the formation and evolution of galaxies.

And in 1967 something magical was found.  A radio beacon was flashing once every 1.33 seconds.  No natural source of such a bright and quickly changing entity occurred to the Astronomers who discovered it.  So they initially christened it LGM-1 for the first signal from what might be Little Green Men or more formally space aliens.  As other sources were detected the name was changed to Pulsars.  Pulsars are Neutron stars.  They are small enough that they can rotate 1.33 times per second without violating the laws of physics.  So if they have an energy source somewhere on their surface it can flash like the rotating beacon in a lighthouse.  What makes it possible to have a very small very energetic object is the collapse of a star.

nucleuses jammed right up against each other with no surrounding cloud of electrons to keep them far apart.  If this happens you end up with what Astronomers have come to call a Neutron Star.  Such a star would be only a few miles in diameter but it would weigh more than the Sun.  It is easy to imagine such a small object rotating in a full circle in about a second.

So why were Neutron Stars, Pulsars, and Black Holes not discovered by the time Asimov wrote his book?  The answer is that a lot of the evidence for these objects can not be gathered from the surface of the Earth.  You have to put a satellite into orbit.  From there it becomes possible to observer the many kinds of electromagnetic radiation that are blocked by the earth's atmosphere.  Much of the early evidence for the existence of these objects and for the data that resulted in insight into their structure came from satellites launched in the '60s after the book was written.  Since then we have launched more sophisticated satellites that have been able to gather more and better data.  We have also improved our ability to make ground based observations.  We have learned how to tie multiple radio telescopes together.  We have even succeeded in tying multiple optical telescopes together in some cases.

50 Years of Science - part 3

This the third in the series.  The first one can be found at http://sigma5.blogspot.com/2012/07/50-years-of-science-part-1.html.  Taking the Isaac Asimov book "The Intelligent Man's Guide to the Physical Sciences" as my baseline for the state of science as it was when he wrote the book (1959 - 1960) I am examining what has changed since. For this post I am continuing with the chapter Asimov titled "The Birth of the Universe".

In part 2 I discussed the age of the Earth.  In discussing the age of the Earth Asimov broaches the subject of "the solar paradox".  Cutting to the chase, Lord Kelvin did a calculation in the late 1800s that indicated that the Sun could be no more than 50,000 years old.  Why?  Because there was no known energy source that could keep it burning any longer.  The two main candidates:  "It's all coal", and gravitational collapse couldn't provide enough energy to explain the steady output of the Sun for any longer.  The discovery of radioactivity in 1896 provided an alternate energy source powerful enough to save the day.  Radioactive decay could provide enough energy to keep the Sun shining at its current level for billions of years.  Over the next forty years subsequent scientific progress allowed scientists to conclude that the Earth and Sun were each about 5 billion years old, very close to the modern figure of 4.7 billion years.  (Modern cosmology posits that the Sun and all the planets, including Earth, were created at almost the same time).

In examining the question of the age of the universe as a whole Asimov gives us a nice description of the Doppler effect.  Let's say you are driving on a road and an emergency vehicle is coming the other way.  Before it reaches you the siren will have a slightly higher than normal pitch.  After it has passed the siren will have a slightly lower pitch.  This shifting of the pitch as a result of motion is called the Doppler effect.  There are many references, including Asimov's book that can give you more detail.  But the bottom line is that this change in pitch can be used to calculate the speed of the other object.

Doppler, the physicist the phenomenon is named after, decided in 1842 that this effect could be used to calculate the speed toward or away from the earth of celestial objects by examining the "spectrum" of these objects.  For reasons that were not well understood until Quantum Mechanics were developed about 1930 when you heat something to an appropriate temperature it will glow.  The intensity of various colors in this glow are called the spectrum of the object.  An individual spectrum will contain features.  At some frequencies the intensity will be particularly bright (emission features) and at other frequencies the intensity will be particularly dim (absorption features).   An object that has the same composition and temperature will always have the same spectrum with the same emission and absorption features.  And the combination of the temperature and the atomic and molecular composition precisely determines the details of these spectral features.  In short, from the spectrogram of an object you can determine its precise composition and temperature.  The process may be very complicated for objects with a complex composition but that's the idea.

Note that I indicated above that an object's spectrum depends solely on its temperature and its composition.  But if the object is moving with a speed that is a noticeable percentage of the speed of light (and the amount of speed that is needed to qualify as "noticeable" keeps dropping as scientific instruments keep getting better), the spectral features will shift.  If the object is traveling toward the earth the frequency will shift higher and the wavelength will shift lower.  Astronomical short hand for this is "blue shift".  If the object is traveling away from the earth the frequency will shift lower and the wave length will shift higher.  The astronomical short hand for this is "red shift".  The amount of shift allows the relative speed to be calculated precisely.  Astronomers make very precise measurements of the spectrum of an object.  Then they identify well known features in the spectrum.  Then they calculate how far and in which direction (higher or lower) the feature has shifted.  From this information a simple calculation yields the speed at which the object is moving and whether it is moving toward or away from the earth.

Now if astronomical objects moved randomly you would expect that about half would show red shift and half would show blue shift.  But it turns out that almost every astronomical object shows a red shift.  Almost everything is moving away from us.  An astronomer named Silpher was the first to notice this in 1914.  Before going on let me discuss the issue of "standard candles".

How do you figure out how far away something is?  Well the simplest and most reliable method is to simply pace it off and measure it.  But what if the distance involved is too great to measure directly?  For longer distances there is a trigonometry based technique called parallax.  Again assume you are in a car.  You are driving down a straight rural road and staring sideways out the window.  This is OK because you are a passenger, not the driver.  Notice that the sections of fence near the road whiz by quickly.  But if you look out across a field at a house or barn it will move slowly as you drive along.  Finally if you look at a mountain a long ways away on the horizon it doesn't move at all.  That's the basic idea behind parallax.  You need to dress it up with trigonometry and careful measurements but if you measure the distance you travel down the road and the change in the angle of the barn or house you can calculate the exact distance it is from the road.  Taking the basic idea and applying the proper measurements and trigonometry is how astronomers can measure distances across space.  But before continuing let me take a second digression and talk about astronomical distances.

People really don't understand how big space is.  Say you get in a car and drive for an hour on a straight road at 50 miles per hour.  (I know, I know, no road is straight for that long but work with me on this).  Everyone has done something like this and it gives them some emotional idea of how far 50 miles is.  Now imagine driving at 50 miles per hour (I have picked this speed because it makes the math easier) for ten hours straight.  You have now gone 500 miles.  Now most people who are stuck in a car for ten hours straight tend to day dream a good part of the time even if they are the driver.  So even a distance of 500 miles, while intellectually comprehensible in terms of our ten hour trip at 50 miles an hour, loses a lot of its sense of concreteness.  I contend that 500 miles is about as far as people can realistically have a concrete feel for.  It is possible to get in an airplane and go thousands of miles.  But you get in the plane.  You may even look out the window for the whole trip.  But a plane ride is emotionally like using a teleporter but with a couple of hours of delay thrown in.  You don't get a real sense of the distance involved.

Now imagine a trip around the world at the equator, a distance of 25,000 miles.  In our car this would require 50 days of 10 hours per day driving.  If people tend to zone out in one 10 hour drive there is no way they are going to be paying attention every day for 10 hours for 50 days in a row.  So I contend that 25,000 miles, the circumference of the earth, is such a great distance that it is not really comprehensible.  But 25,000 miles is infinitesimal in terms of typical astronomical distances.  So all astronomical distances blur together and become "so large as to be unimaginable" in concrete terms to a person.  Scientists can do the math but the numbers are so large as to be meaningless to us.  And since we can't in any real sense comprehend these numbers we make really wild mistakes all the time.  Some numbers are really a lot bigger than other numbers.  But they are all so large that our emotions misread them and we think of them as being nearly the same size or we get it wrong as to which is really the larger and which is really the smaller.  Back to the subject at hand, namely parallax.

Parallax works well enough to be able to estimate distances within the solar system with a reasonable degree of accuracy.  The most useful "baseline" for measuring these kinds of distances is the orbit of the earth around the Sun.  It is about 100 million miles.  Compare this to the circumference of the earth at 25 thousand miles, a distance I said was too great to be emotionally comprehensible.  Well this distance is 40 times as great.  It seems inconceivably large.  But it is actually quite small.  And things get a very slight bit better.  The earth goes all the way around the Sun.  So at one point it is 100 million miles this way and six months later it is 100 million miles that way.  So the distance between the extremes is 200 million miles, a number that is twice as big.

If we want to use the parallax technique to figure out how far away something is then what we want to do is wait for the earth to be on one side of the Sun and then carefully measure the angle to the "something".  Then we wait 6 months and measure again.  We are now 200 million miles away from where we started so the angle should change a lot, right?  Well, this is where our intuition goes wrong because we are comparing these giant numbers.  The closest star to us that is not the Sun is Proxima Centauri.  Most people think it's Alpha Centauri because that's what a lot of people say.  Alpha Centauri and Proxima Centauri are very close together but Alpha Centauri is a lot brighter so people usually go with it.  But Proxima Centauri is actually a little closer.

Anyhow with this giant baseline of 200 million miles it should be a piece of cake to do the parallax thing to find out how far away it is.  And the parallax trick actually works for Proxima Centauri (and Alpha Centauri too) but just barely.  The reason is because the star nearest our own is actually a very long way away.  Let's see how long "very long" is.  To do this I am going to figure distances in "light minutes".  A light minute is the distance traveled by a photon of light in a minute.  Trust me, it's a very big number.  Now the light from the Sun takes a little over 8 minutes to get here from there.  So a hundred million miles is about 8 light minutes.  And 200 million miles is about 16 light minutes.

Now Proxima Centauri is 4.25 light years away (the distance light goes in 4.25 years).  Again this is a really big number if we put it in terms of miles.  But let's put it in terms of light minutes.  It still turns out to be a pretty big number.  Proxima Centauri is about 2.2 million light minutes away.  So to do the parallax thing to figure out how far away Proxima Centauri is we create a triangle.  One side of the triangle is 16 light minutes long.  The other two sides are 2.2 million light minutes long.  In geometry there is a concept called "similar triangles".  By using similar triangles we can throw all the "million" parts away.  So imagine a triangle with one side that is 16 inches long and the other two sides are 2.2 million inches long.  It turns out that the 2.2 million inch sides are each over 35 miles long.  Now to get the parallax thing to work we need to measure the tiny angle between the two 35 mile long sides.  Remember on one end they meet and on the other end they are 16 inches apart.  It is a brilliant piece of work that Astronomers have actually been able to measure that super tiny angle.

Now let's try to do the parallax technique on a star that is twice as far.  That means that we need to measure the angle between the two sides that are now 70 miles long.  Remember that they meet at one end and are separated by the same 16 inches on the other end.  Astronomers have only been able to use the parallax technique to measure the distance to only a few of the nearest stars.  I think you now understand why.

So if the parallax technique only works for a few very close stars what do we do about the rest?  The answer finally gets us back to the "standard candle" technique that I mentioned a long time ago.  Imagine having a 100 watt light bulb.  Now measure how bright it is from 100 yards away.  There is a standard mathematical formula that tells us exactly how bright it will be when viewed from 200 yards away or a thousand yards away.  So if we know we are looking at our 100 watt light bulb (so we know exactly how bright it is) and we can very accurately measure how bright it appears to be (called its "apparent brightness") then we can calculate how far away it is.  That's the idea behind "standard candle".  If we know how bright something is from close up, its "intrinsic" brightness, and we can measure its apparent brightness, and we know that everything is clear between it and us, then we can calculate how far away it is.

Now most of space is pretty empty.  So it conforms to the "everything is clear" requirement to use the technique.  Sometimes this is not true.  There are dust clouds and other things that get in the way.  And these present real problems for some measurements scientists would like to make.  But in a lot of cases there appears to be no obstruction and in other cases scientists come up with techniques to allow them to adjust for the amount of obscuring going on.  So a lot of the time this "everything is clear" requirement is met.  That leaves the problem of knowing the intrinsic brightness of what you are looking at.

A solution to this problems is discussed by Asimov.  It involves the use of Cepheid variables.  These are a kind of variable star. The brightness of the star varies in a predictable way.  What makes this important is that Astronomers came to understand enough about how Cepheid variables worked that they could predict the intrinsic brightness of the star based on the specifics of its pattern of variability.  Originally work determined that specific types of Cepheids all had the same intrinsic brightness.  This allowed the development of a relative distance scale.  This item is twice as far away as that item, that sort of thing.  Soon a large number of relative distances were known.  But to turn the relative distance scale into an absolute distance scale it was only necessary to determine the actual distance to one Cepheid.  That was only achieved recently when high precision measurements using the Hubble Space Telescope and other techniques became available.

At the time Asimov wrote the book only relative distances were known for sure.  Astronomers used a number of techniques to estimate the intrinsic brightness of Cepheids with more or less success.  At the time the book was written there was still a lively discussion as to what the correct value for the intrinsic brightness was.  This resulted in a number of respected Astronomers using a number of different estimates of intrinsic brightness.  As time went by Scientists also determined that there were several classes of Cepheids and members of each class displayed a different intrinsic brightness than apparently similar members of a different class.  General agreement as to how to place a specific Cepheid into the right class and the correct intrinsic brightness for each class are now pretty much sorted out.  But bringing everything into alignment was not completed until many years after Asimov's book was written.  Astronomers were very aware that there were problems with Cepheids at the time the book was written.  But there was no better way to determining distances at the time.  And Astronomers of the time were careful to acknowledge these kinds of issues.

Also at the time Asimov wrote the book Cepheid variables were the brightest standard candle available.  But for really large distances they are too dim to work.  Since then Astronomers have developed another standard candle called a "Type 1A Supernova".  As a supernova it is way brighter than a standard star like a Cepheid so it works for much greater distances.  All of the details of how the intrinsic brightness of a type 1a supernova has been worked out are different.  But the general idea is the same.  Certain attributes that can be measured from far away allow the intrinsic brightness to be determined.  There have been problems to work through with the type 1A supernova as a standard candle.  But Astronomers think they have things worked out pretty well at present.  Now back to the main line of the story.

In 1929 Edwin Hubble, who had been studying Galaxies published Hubble's Law.  Using Cepheids as standard candles Hubble had found that if you ignored a few close in Galaxies it appeared that the farther away a Galaxy was the faster it was moving away from the earth.  He posited that there was a single "Hubble Constant" that was the ratio between the recession speed and the distance from the earth.  Do to the problems with the Cepheid standard candle he couldn't establish the specific value for the Hubble Constant but he established that it appeared to be a constant across the range of relative distances he could measure.

This turned out to be a very remarkable observation.  Using Hubble's Law one could project to the point where galaxies would be receding from each other at the speed of light.  This in turn meant that the universe had a specific age.  This idea was shocking.  Before, scientists had not spent much time thinking about the age of the universe.  They knew it was vastly older than the 6,000 or 10,000 years that biblical scholars had calculated.  Other than that, most thought, when they thought about it at all that the universe was either a vast unspecified age or that it had always been there in something similar to its current state.  Hubble's ideas ushered in the modern era of cosmology.

As these ideas spread among first the Astronomical community and then to the broader scientific community speculation soon settled down into two main competing theories.  The "steady state" theory was championed by among others Einstein and a British Astronomer named Fred Hoyle.  It stated that the universe had always looked pretty much as it does now.  The competing theory, named by Hoyle with the most ridiculous name he could think of, was called the "big bang" theory.  By the time Asimov's book was written the evidence against "steady state" had become overwhelming.  So "big bang" was winning by default.

It didn't take scientists long to note some convenient features of Quantum Mechanics in their efforts to flesh out the big bang theory.  The most relevant item was something known as the Heisenberg Uncertainty Principle.  Most simply (and I don't want to get into yet another diversion so this is all you get) the Principle said that there was a fundamental uncertainty about the universe and that the smaller the thing you were studying the more uncertain its characteristics were.  Astronomers latched on to this and posited an extremely small piece of space.  It was so small that the energy content was vastly uncertain.  This was taken as the seed out of which the whole universe would explode.  As the universe exploded it would cool (that's what gasses naturally do as they expand) and eventually the temperature would drop to what we see today and the size of the universe would grow to the size we see today.  That was roughly the state of the big bang theory at the time Asimov wrote his book.

You are probably thinking that seems inherently implausible.  Scientists slowly came to the same conclusion.  And the big bang theory has evolved considerably from the humble roots I outlined above.  The biggest change is to add something called "inflation".  The subject is complex and I again want to avoid digression.  But the basic idea is that from its early tiny seed (which may have looked greatly different than our tiny exploding point) the universe inflated to a fantastic size in a fantastically short period of time.  This may sound even weirder than the very weird original big bang theory I outlined above.  But it turns out that there is actually some evidence for inflation.  Yet again in an attempt to avoid another large diversion I will note that the most compelling of this evidence consists of the measured variations in something called the Cosmic Microwave Background and leave it at that.

Asimov does a nice job of going into Hubble's work and that of subsequent scientists up to the time he wrote the book.  Given all the uncertainties scientists supported age estimates for the universe ranging from about 11 billion years to 42 billion years.  Since then the uncertainties have been greatly reduced and the consensus number today is 13.7 billion years.

Since then another startling development has transpired. It looks like the Hubble Constant is not constant.  There is evidence that the rate of expansion of the universe has changed over time.  There have also been related developments in scientist's views on the constitution of the universe.  At the time Asimov wrote the book what Astronomers could see were bright things like stars.  Generally this is referred to as Baryonic matter.  A couple of decades ago Astronomers noticed a problem.  They could roughly weigh a galaxy by doing some calculations based on the light the galaxy generated.  They could then use Newton's theory of gravitation to predict how fast portions of the galaxy should rotate.  Everything came out wrong.  Eventually Astronomers decided that there was a large amount of what they dubbed "dark matter" surrounding galaxies.  They still have no idea what dark matter is but there seems to be a lot of it.  The recently measurements that have led to the idea that the Hubble Constant is not constant has let scientists to posit something called "dark energy".  They know even less about dark energy than they do about dark matter.  But their current thinking is that the universe consists of about 4% Baryonic matter, 26% dark matter, and 70% dark energy.  So scientists in 1960 knew about only 4% of the mass that current day scientists think the universe actually contains.

And this leads me to my final subject for this post.  Scientists in 1960 envisioned three basic fates for the universe.  The first option was that the universe would explode (big bang), expand for a while, then collapse back on itself.  This was dubbed the "cyclic universe" theory.  At the other extreme the universe would explode then keep on growing.  It would get bigger and bigger.  Everything would spread farther and farther apart until each component of the universe was an island so far away from any other component as to be completely isolated.  The third option was the happy medium one.  The universe would explode and expansion would gradually slow down due to gravity but everything would be on a balance point,  It wouldn't expand forever but it wouldn't collapse back either.  Which would be the fate of the universe?  Well it all depended on the density of the universe.  If it was too dense it would expand then collapse.  If it was not dense enough then it would expand forever.  And if the density was just right if would end up on the balance point.

In 1960 these calculations had been done and it appeared that the universe had exactly the right density to end up at the balance point.  But scientists were completely at a loss as to why the density of the universe was exactly right.  Even a little too much or a little too little would tip the universe one way or the other.  Since then we have this whole dark matter / dark energy thing going.  Factoring everything in, Baryonic matter, dark matter, dark energy, the universe seems to have exactly the correct density.  But current measurements indicate that the density is so ridiculously exactly the correct amount that they are even more puzzled by the whole thing than they were in 1960,

And that gets us to the end of the chapter.  

50 Years of Science - part 2

This is the second in a series of posts.  The first one can be found at http://sigma5.blogspot.com/2012/07/50-years-of-science-part-1.html.  Taking the Isaac Asimov book "The Intelligent Man's Guide to the Physical Sciences" as my baseline for the state of science as it was when he wrote the book (1959 - 1960) I am examining what has changed since.  For this post I am starting with the chapter Asimov titled "The Birth of the Universe".

In this chapter Asimov reviews in more detail than in previous chapters what science has determined about the age of things.  He reviews various "origin stories" for the Earth, including the one in the Bible.  He then moves quickly on to scientific attempts to determine how old Earth is.  Based on the salt content of the ocean the earth is at least a billion years old.  Based on various radioactive decay-based measurements the Earth is at least 3.3 billion years old.  Both of these estimates contradict "young earth" creationists.  Asimov doesn't mention them anywhere in the book because at the time the book was written no one took them seriously.  They did not have a political home in the Republican party and a well established network of religion channels on cable and mega churches to support and maintain their belief system.  In the decades since this book was written science has developed and enhanced the lines of reasoning Asimov lists, along with dozens of others, all indicating that the Earth is billions of years old.

No one has come up with any credible evidence that even one of these multiple lines of reasoning is wrong.  But we live in a world where people's knowledge of science has diminished to the point where most people are unfamiliar with the reasoning or the evidence that supports the reasoning.  Instead they are drowned in a sea of "facts" that are factually wrong, and people whose idea of a scientifically valid argument is " I believe it because my faith demands I believe it" or "I believe it because I wish it were so and 'wishing it were so' is enough to make something true".

In any case, the basic methods Asimov discusses have been refined and extended so that we now know that the Earth is 4.7 billion years old.  The primary line of evidence for this is radioactive decay.  Why is the modern number different from the number in 1960?  The big reason is that a concerted effort has been made to date lots and lots of rock formations.  When rocks melt then many radioactivity "clocks" reset resulting in a misleadingly young estimate of how old the rocks are.  Scientists have now located rock formations that are substantially older than the oldest ones they were familiar with in the '60s.  The scientific methods of radioactive dating have also gotten better.  More isotopes can now be used as the basis for these radioactive studies.  The amount of material necessary to make an accurate measurement is now much smaller.  And the overall accuracy and sensitivity of the measurements have improved.  Scientists are now also able to measure different "isotope systems" in the same rock and compare the results.  This makes it easier to identify situations where a sample appears to be pristine but has actually been processed (e.g. heated up by a geologic process).

Now is probably a good time to spend some time explaining how radioactive clocks work.  The thing that makes an atomic element what it is is the number of protons in the nucleus.  Hydrogen is Hydrogen because its nucleus has one Proton.  Helium is Helium because it has two Protons in its nucleus.  But there are actually multiple kinds of Hydrogen, Helium, and other elements.  Each kind is called an isotope,  The three isotopes of Hydrogen are called "Hydrogen", "Deuterium", and "Tritium".  Regular Hydrogen has a nucleus consisting of one Proton.  That's it.  Deuterium has a Proton but also a Neutron in its nucleus.  The name references the two (deu) nucleons.  Tritium has a Proton and two Neutrons, hence the "tri" in the name.  The isotopes of other elements don't have such cute names.  Chemists and Physicists also have various superscripts and subscripts they use to indicate isotopes but it is essentially impossible to get these to print correctly in the blog.  So I am instead going to use H-1 to indicate Hydrogen with just the one nucleon in its nucleus, H-2 to indicate Deuterium, the isotope of Hydrogen with two nucleons, and H-3 to indicate the three nucleons in Tritium.

Now from a chemical point of view H-1, H-2, and H-3 are indistinguishable.  They all behave like Hydrogen in every way when it comes to chemical reactions.  The same is true for the isotopes of Helium:  He-2, He-3, and He-4.  In each case there are two Protons in the nucleus along with 0, 1, or 2 Neutrons.  As a result each isotope acts just like the others from a chemical reaction point of view.  But in other ways each isotope differs.  For one thing the weight of each differs.  An atom of H-2 weighs about twice as much as an atom of H-1.  Both have one Proton and, in normal circumstances one electron.  But the electron weighs about one 2000th as much as a Proton, whereas a Neutron weighs roughly the same as a Proton.  So H-1 has one Proton and 1 electron and weighs about as much as a Proton.  But H-2 has a Proton, an Electron, and a Neutron.  So it weighs about the same as two Protons.  When you get to heavy atoms like U-235 versus U-238 the difference is much smaller.  U-235 weighs roughly as much as 235 Protons and U-238 weighs roughly as much as 238 Protons.  But here the difference in weight is roughly 1%.  In some cases the weight difference can be important but in most cases the difference in not enough to make a big difference.  And in any case that is not what we are interested in.

The difference that matters to us is that the stability of various isotopes varies considerably.  H-1 is stable.  If you sit around and watch a H-1 atom for a very long time it won't do anything.  H-2 is also stable.  But if you watch H-3 for about 12 years there is a 50-50 chance that it will "decay" into something else.  It will stop being H-3 and become a different isotope of a different element.  It will spontaneously become He-3.  One of the Neutrons will turn into a Proton.  If you have a bunch of H-3 atoms and wait a little over 12 years 50% of it will spontaneously decay into He-3.

There are 92 naturally occurring elements.  They range from e.g. H-1 to e.g. U-238.  Hydrogen comes in three isotopes as does Helium.  Other elements like Uranium come in a dozen or so isotopes.  All together there are hundreds of isotopes.  Many like H-1 are stable.  They never decay into something else.  But most isotopes are like H-3 and U-235 and U-238.  They decay spontaneously into other isotopes.  This is a complicated process.  U-235, for instance, can decay into one of several isotopes.  And sometimes the isotope it decays into is radioactive (e.g. unstable) so it decays into something else.  But scientists have carefully studied many isotopes and for the radioactive ones they have studied what they decay into.  H-3 always decays into He-3.  And for a combination like H-3 to He-3 there is a single magic number called the "half life".  In the case of the H-3 to He-3 decay the half life is exactly 12.32 years.  This means that if you put 10 lbs of H-3 into a container and wait exactly 12.32 years, when you look into the container you will find 5 lbs of H-3 and 5 lbs of He-3.

U-235 is more complicated.  It can decay into a number of different isotopes.  But most of the time it decays into Th-231.  The half life of this decay is 700 million years.  U-238 has three different decay paths.  The most common one is to Th-234 and its half life is 4.5 billion years.  What's important is for each decay path (e.g. H-3 to He-3 or U-235 to Th-231) you have three things:  the starting isotope, the ending isotope, and a very specific half life.  As we have seen half lives can be relatively short (e.g. 12.32 years) or very long (e.g. 4.5 billion years).  They can even be much shorter.  The half life of some isotopes is less than a second.  And they can be even longer than 4.5 billion years.  But, since 4.5 billion years is about as long as the Earth has been around, decay paths that have a half life longer than 4.5 billion years are not very useful as radioactive clocks.

And this whole half life thing is a little more complicated than it looks.  If we look in on our container of H-3 after 12.32 years we have half as much H-3, namely 5 lbs.  But what if we seal it back up and wait another 12.32 years?  Is it all gone?  No!  "Half life" means the amount of time it takes for half the remaining material to decay.  So after a total of 24.64 years we will have 2 1/2 lbs of H-3 (half the 5 lbs we had at the 12.32 year mark).  Radioactive decay is what mathematicians call an exponential process.  After one half life we have half the material.  After two half lives we have a quarter of the material.  After three half lives we have an eighth of the material.  And so it goes to a sixteenth (4 half lives) a thirty-second (5 half lives) a sixty-fourth (6 half lives).  If a large number of half lives are involved there is a shortcut that can be used.  After ten half lives we will have about a thousandth of the material left.  After twenty half lives we will have about a millionth, etc.  Every additional ten half lives will reduce the amount of original material by a factor of a about a thousand.

This whole "isotopes and half lives" thing gives us a clock for measuring times.  If we know how much of a specific isotope we started with and we know how much we have now then we can measure time.  For periods of hundreds to tens of thousands of years C-14 (carbon fourteen) works really well.  Lots of things like wood have carbon in them.  Most Carbon is stable C-12.  There is also some C-13, which we will ignore.  But there is usually a small amount of C-14 mixed in with the other isotopes of Carbon.  The half life of C-14 is 5,730 years.  If by careful analysis we find that exactly half the C-14 we started with is gone we can conclude that the artifact containing the Carbon is 5,730 years old.  If a quarter remains then the artifact is a little over 11,000 years old.  If a little less than a thousandth of the C-14 is left then the artifact must be about 57,000 years old.  In theory the process is that simple.  In actual practise it is more complicated than that.

The most obvious problem is with an artifact that we suspect is a little over a hundred thousand years old.  In this case we expect to measure about a millionth of the C-14 we started with.  That's not very much.  So C-14 dating is not very good for artifacts that are more than about 50,000 years old as the remaining amount of C-14 is so small.  But there is an even bigger problem for an artifact that we suspect is say 20,000 years old, what should be in the butter zone where we should have enough C-14 left over to get an accurate enough measurement to produce a pretty sharp age estimate.  Now the issue hangs on the question of how much C-14 we started with.  And that turns out to be a much harder question than it would seem.

Originally scientists just assumed that everything started out with pretty much the same percentage of C-14.  So they would measure the total carbon, apply the magic percentage to estimate how much C-14 there originally was, and go from there.  But it turns out the magic percentage trick doesn't work very well.  C-14 comes from high altitude cosmic rays hitting the upper atmosphere.  If the rate of cosmic rays stays constant then after a while the carbon in the atmosphere will contain a specific percentage of C-14.  This C-14 will end up in carbon dioxide in the air.  And plants will absorb the carbon dioxide and end up with a specific percentage of C-14 in their tissues.  If the plant lives for a very short time compared to the 5,730 year half life of C-14 then we will end up with plant material with a predictable initial C-14 percentage and we are good to go.  But this process is complicated and it turns out that there are variations in the efficiencies of some of the steps.  So the percentage of carbon in plant material that is C-14 varies somewhat.  And this introduces errors.  We can still measure what is now called the C-14-age of material containing carbon.  Scientists have developed elaborate adjustment procedures that work pretty well most of the time for turning C-14 age into real age.  But they are complicated and don't work all the time.

So some times there are problems with C-14 based radioactive dating.  Scientists have reacted to this in two ways.  First, they have developed and continued to refine their C-14 adjustment procedures.  The second way is to come up with other isotope systems.  That way they can compare the results for the C-14 isotope system with the results of the other isotope system.  Other isotope systems also allow artifacts to be dated that are much older than 50,000 years.  For instance, if you can find some Uranium in a rock and you can estimate how much of that Uranium was originally U-238, you can use radioactive dating on a very old rock.  If you measure the remaining U-238 and it turns out to be half of the amount you calculated was originally there you can estimate that the rock was 4.5 billion years old.  Other isotope systems can be used in situations where your age estimate is different.  If you can use an isotope system that has the right half life you can get an accurate and reliable date for a range of from hundreds of years to billions of years and anything in between.

This digression has turned out to be much longer than I originally planned.  So let me stick with it just a little longer and explain how scientists figured out that the C-14 isotope system had problems.  They didn't match it against a different isotope system.  Instead they matched it against a completely different dating system called dendrochronology.  This is just a fancy name for counting tree rings.  People have known for a long time that if you cut tree down you will see rings.  And each ring represents a year in the life of the tree.  The rings represent wood of different colors.  And the explanation is simple.  In the Spring when the weather is nice the tree grows quickly and typically creates light material.  In the winter the tree grows more slowly and typically creates darker material.   This idea of annual tree rings has been around a long time and was certainly not invented by scientists.  But scientists took this basic idea and built on it.

Scientists observed that a wide ring represented a year with good growth weather and a narrow ring represented a year with poor growth weather.  Originally this idea was used to determine weather patterns for times and places where there weren't good weather records.  But scientists found a way to do even further.  All the trees in a specific stand experience the same weather so they will have the same pattern of narrow rings for poor growth years and wide rings for good growth years.  This allows the pattern of rings to be synchronized between different trees.  Specifically, if you can find the stump of an old tree in a stand with younger trees you can match rings from late in the life of the stump with rings early in the life of the younger trees.  This allows you to establish the time period when the old tree was alive.  You now have access to weather information going farther back than the age of the oldest tree still alive.

This idea can be extended to trees in different stands as long as the stands are subject to similar weather.  And this method can be used to develop a weather record that spans not just two trees but several trees.  So a record can be developed that spans hundreds, in some cases thousands of years.  And the method does not require a whole tree.  A beam from a house or any piece of wood big enough to contain a number of rings can be used.  So a beam from a building or a piece of furniture can be dated.  You know the object containing the piece of wood was constructed some time after the tree that originally contained the piece of wood died (e.g. was cut down).  This allows you to date the piece of wood as being after the newest date represented by the newest ring in the piece of wood.  This can be very useful.

Specifically, wood contains carbon.  You can take a small sample from piece of wood and C-14 date it.  You can then compare this C-14 date to the tree ring date for the larger piece of wood.  You may even know the exact year the rings were laid down that ended up in the small piece that was C-14 dated.  Scientists did that.  They had complete confidence in the tree ring dates.  They found, however, that the C-14 date did not match.  That caused them to go back and look harder at the C-14 system and decide it had problems.  They now know what these problems are.  But there is not always a method of correcting the C-14 date that works.

Scientists do this kind of thing all the time.  They test one method against another method to see if they agree.  It's nice when the do but they don't always.  When there is disagreement they go back and look at both methods to see if they can figure out what went wrong.  Most of the time when it turns out that something is wrong it is scientists and not the critics that figure out that there is a problem.  When it comes to legitimate criticism, criticism that turns out to be justified when all the facts are in, Scientists are much harder on Science than critics are.