Freethought & Rationalism Archive

Happy Wonderer · 02-27-2003, 11:03 AM

Quote:

Originally posted by Albert Cipriani

Ditto for information. All the energy in the universe only adds up to the Big Bang. I see information as something qualitatively different than energy.

Exactly! So why would information have the same properties as energy? Why would the laws of thermodynamics have anything more to do with information and complexity than, say, the laws of Hammurabi?

Let's take one property of energy: energy cannot be created or destroyed, but can only be changed from one form into another. This is a basic property of energy, and is a critical assumption of the second law. It is pretty clear that this doesn't apply to information, which is created at a very rapid rate.

If you want to argue that there is a 2LoI you can't use thermodynamic arguments.

HW

(Edit to make a critical assumption of second law instead of low.)

Baloo · 02-27-2003, 12:34 PM

Quote:

With complete information, no process is unpredictable. So randomness or chance are just other words that mean the same thing as crying �Uncle� in the face of processes more complicated than we can hope to divine.

This may be a quibble, but the above is false. Quantum mechanics, if true, asserts that even if you know everything about an unstable isotope, it is impossible to predict when and how it will decay. The decay property, prior to the decay event, literally exists as a simple probability distribution function. All accumulated knowledge of the isotope can only increase the accuracy of the p.d.f. And 100% certain knowledge of the p.d.f. itself can only be used to predict the probablity of the isotoped decaying in, say, the next 5 seconds vs the next 5 years.

As my theistic professor described it: God created a universe where not even He, with full knowledge of only the present and past, could predict the future of a single isotope.

Or so I recall from Quantum Chemistry back in college...

Albert Cipriani · 02-28-2003, 10:45 AM

Dear Baloo,
If what you say is true, I must do a lot of re-thinking. I thought the Heisenberg Uncertainty Principle referred to the cross-talk between measuring and interfering with our measurments, not to our theoretical ability to, with perfect knowledge, predict perfectly. If you have any more support for your assertion, I would be most appreciative.

I�m leaving the state for about a week. Will check back with you when I come back.

Thank you all for a most stimulating conversation. � Albert the Traditional Catholic

Muad'Dib · 02-28-2003, 02:59 PM

Have a good trip. Hope to see you back soon!

Happy Wonderer · 02-28-2003, 08:37 PM

Quote:

Originally posted by Albert Cipriani
Dear Baloo,
If what you say is true, I must do a lot of re-thinking. I thought the Heisenberg Uncertainty Principle referred to the cross-talk between measuring and interfering with our measurments, not to our theoretical ability to, with perfect knowledge, predict perfectly. If you have any more support for your assertion, I would be most appreciative.

I�m leaving the state for about a week. Will check back with you when I come back.

Thank you all for a most stimulating conversation. � Albert the Traditional Catholic

Have a good trip, it has been fun! Don't forget to feed the
Cat.

HW

Lobstrosity · 02-28-2003, 09:31 PM

Quote:

Originally posted by Albert Cipriani
Dear Baloo,
If what you say is true, I must do a lot of re-thinking. I thought the Heisenberg Uncertainty Principle referred to the cross-talk between measuring and interfering with our measurments, not to our theoretical ability to, with perfect knowledge, predict perfectly. If you have any more support for your assertion, I would be most appreciative.

Baloo is right. The uncertainty principle does not encapsulate a lack of technology to make measurements; it rather represents the physically impossibilty of ever simultaneously knowing two non-commuting observables with perfect accuracy.

If you wish to learn more about this I urge you to look into the Bell inequalities. Quoting from one text I own (A Moder Approach to Quantum Mechanics by John Townsend):

"Until 1964 it was believed that one could always construct a hidden-variable theory that would give all the same results as quantum mechanics. In that year, however, John S. Bell pointed out that alternative theories based on Einstein's locality principle actually yield a testable inequality that differs from the predictions of quantum mechanics."

As you may or may not know, Einstein thought that the notion of hidden-variables (e.g. little hidden clocks in radioactive isotopes that determine when decay will occur) was the true picture of our world. He could not believe that God would "play dice" with the universe. He would have held your view of the Heisenberg Uncertainty Principle: that something actually has both definite position and momentum simultaneously, but we can only ever measure either one or the other with perfect accuracy (just not both). It turns out Einstein was wrong in this regard--an object does not actually have definite position and momentum simultaneously. Experimental findings, when compared to Bell's calculations, have demonstrated that the notion of local realism is faulty (one experiment showed that while the predictions of quantum mechanics were excellent, the Bell inequality was violated by more than nine standard deviations).

A good paper to review on this subject would be:
A. Aspect, P. Grangier, and G. Roger, Physics Review Letters 49, 91 (1982)

diana · 03-01-2003, 11:53 AM

Albert,

I'm back. My apologies--I forgot about this thread after starting it. I've been busy elsewhere.

Fascinating reading. Excellent thread. I see a testosterone competition between you and pz, but...that's par for the course. (But then, I seem to have that problem with people occasionally, too. Maybe I should rename it.)

I'd respond to your post to me, but it would be repetitious, as Gregg has already expressed the thoughts I would have, except--just like livius drusus, when we chance to cross paths--only better. (Thanks, Gregg.)

I transferred you here because I know little about evolution. I'm learning as I go, too.

d

diana · 03-01-2003, 11:54 AM

Quote:

Originally posted by Muad'Dib
Oh no! I think the universe is about to disappear in a puff of logic!

More or less, yep.

Sounds good. I won't presume to speak for pz, but my objection is that potential is awfully hard to quantify, especially if you take into account the restricted "potential" of the individual molecules and atoms actually forming the cell, that might otherwise be off doing other things. Don't get me wrong, I don't think it's an uninteresting idea; it's just that the tools we've been using (G2LoT, etc.) don't have the resources to take that into account.

Here's an analogy that may or may not work. Please forgive me if I exceed my knowledge of poetry!

In literature generally and poetry specifically, there are rules. These are not absolute rules; they vary from generation to generation and sometimes from region to region, but people who know the field are aware of these rules and whether consciously or unconsciously, they abide by them the vast majority of the time.

Occasionally, good or great poets will break the rules--sometimes just one, somtimes more than one--and the result will take the literary community by storm. Indeed, their work may be so influential that their breaking of a rule may very well become the new norm.

Now, this observation might lead a clueless person like me to say, "Hey, to be a great poet, all you have to do is break the rules!" But as any high school english teacher will tell you, the vast majority of people who break the rules write crap. (Or you can call it "second-rate work" if you want to be polite.)

Here's how all this relates to biology.

Say that you would like your friend to e-mail you a copy of Faust. If there is any error in the transmission, what you receive is by definition worse than what she sent you: it is an inferior facsimile of Faust. If you were to propagate your copy to other people, their copies could not be any better than yours (and they may very well be worse). Breaking the rules is always detrimental in such a situation.

Evolution, though, is more like poetry than a straight-up information transfer. Most of the times an organism "breaks the rules" by acquiring a genetic mutation, either nothing happens or it's a bad thing (from the perspective of the organism's survival). But from time to time, a mutation will occur that helps the organism survive and thrive, sometimes so well that after a few (or many) generations that "broken rule" will become the new rule.

Hope that made sense!
Take care,
Muad'Dib

Actually, Maud'Dib, that was an excellent analogy, and mirrors my opinions of poetry (and its evolution) exactly.

Good to have you back.

d

Muad'Dib · 03-01-2003, 07:57 PM

Thanks, diana. I'm glad the analogy worked.

Alix Nenuphar · 03-06-2003, 09:18 PM

Quote:

Originally posted by Lobstrosity
Baloo is right. The uncertainty principle does not encapsulate a lack of technology to make measurements; it rather represents the physically impossibilty of ever simultaneously knowing two non-commuting observables with perfect accuracy.

If you wish to learn more about this I urge you to look into the Bell inequalities. Quoting from one text I own (A Moder Approach to Quantum Mechanics by John Townsend):

"Until 1964 it was believed that one could always construct a hidden-variable theory that would give all the same results as quantum mechanics. In that year, however, John S. Bell pointed out that alternative theories based on Einstein's locality principle actually yield a testable inequality that differs from the predictions of quantum mechanics."

As you may or may not know, Einstein thought that the notion of hidden-variables (e.g. little hidden clocks in radioactive isotopes that determine when decay will occur) was the true picture of our world. He could not believe that God would "play dice" with the universe. He would have held your view of the Heisenberg Uncertainty Principle: that something actually has both definite position and momentum simultaneously, but we can only ever measure either one or the other with perfect accuracy (just not both). It turns out Einstein was wrong in this regard--an object does not actually have definite position and momentum simultaneously. Experimental findings, when compared to Bell's calculations, have demonstrated that the notion of local realism is faulty (one experiment showed that while the predictions of quantum mechanics were excellent, the Bell inequality was violated by more than nine standard deviations).

A good paper to review on this subject would be:
A. Aspect, P. Grangier, and G. Roger, Physics Review Letters 49, 91 (1982)

I believe that the major problem with the hidden variables theory turned on the problem of non-locality; what the Aspect experiment actually did was demonstrate that non-locality is real, not simply a mathematical convenience.

At the moment, there are several researchers working quite hard on hidden variables - although one could suggest that they are doing it for reasons of discomfort with unpredictability rather than because the evidence really trends that way.

The faults of once having been a physicist....

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02-28-2003, 10:45 AM	#73
Albert Cipriani Banned Join Date: Jul 2001 Location: Southern California Posts: 3,018	Dear Baloo, If what you say is true, I must do a lot of re-thinking. I thought the Heisenberg Uncertainty Principle referred to the cross-talk between measuring and interfering with our measurments, not to our theoretical ability to, with perfect knowledge, predict perfectly. If you have any more support for your assertion, I would be most appreciative. I�m leaving the state for about a week. Will check back with you when I come back. Thank you all for a most stimulating conversation. � Albert the Traditional Catholic

02-28-2003, 02:59 PM	#74
Muad'Dib Senior Member Join Date: May 2001 Location: Los Angeles Posts: 845	Have a good trip. Hope to see you back soon!

03-01-2003, 11:53 AM	#77
diana Veteran Member Join Date: Aug 2000 Location: Colorado Springs Posts: 6,471	Albert, I'm back. My apologies--I forgot about this thread after starting it. I've been busy elsewhere. Fascinating reading. Excellent thread. I see a testosterone competition between you and pz, but...that's par for the course. (But then, I seem to have that problem with people occasionally, too. Maybe I should rename it.) I'd respond to your post to me, but it would be repetitious, as Gregg has already expressed the thoughts I would have, except--just like livius drusus, when we chance to cross paths--only better. (Thanks, Gregg.) I transferred you here because I know little about evolution. I'm learning as I go, too. d

03-01-2003, 07:57 PM	#79
Muad'Dib Senior Member Join Date: May 2001 Location: Los Angeles Posts: 845	Thanks, diana. I'm glad the analogy worked.

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