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The universe is increasing in entropy, but life represents a local decrease in entropy. In doing thermodynamic calculations you must consider the system and surroundings.   The entropy of the syste

Basics of DNA:   There are 4 base pairs: Adenine (A) Thymine (T) Gaunine (G) Cytosine ©   These are combined into triplets (that is 3s) to form a condon like this: AAT : Asparagine AGC : Asp

SR doesn't know about gravity, only GR does.

 

The source says differently. It is a .edu site: an academic institution with a physicist talking. You are going to have to do better than simple denial.

 

In the absence of any distiguishing characteristics, we select a theory based on how simple it is.

 

No, we don't. Your example from class is flawed because you were supposed to know an already tested and accepted theory. http://www.ks.uiuc.edu/Services/Class/PHYS480/qm_PDF/chp10.pdf

Not distinguish between 2 different proposed theories. Yes, you "missed the point" because you didn't know the equations that were already out there for relativistic quantum mechanics.

 

But, in trying to evaluate the accuracy or truth of 2 theories, we absolutely do NOT think the simpler is correct. This is particularly true in biology because natural selection -- because it is unable to subtract information -- makes things extremely complex. Selecting theories on simplicity ends up, more often than not, in being wrong. I have a Sid Harris science cartoon I use in my Philosophy of Science lecture whose caption has a quote from Dirac: "It is more important that an equation be beautiful than that it correspond to experiment." Dirac was wrong.

 

And I object to calling the Feynman sum over paths inelegant. Which path does the electron take? ALL paths, of course!

 

I didn't say it wasn't "elegant", I said it was not the simplest equation. The math is much more complicated. Now you are taking my point: use Feynman's equations because that is what the electron actually does, even tho they are not simple.

 

The only types of ethers which are allowed are the types with no reference frame. Which means you can't detect them. This is a bit like saying that evolution is driven by an intelligent designer, you just can't detect her.

 

Some entities that can't be detected are allowed while others are not. It's complicated so try to stay with me.

 

IF the entity can't be detected due to limitations of science or of the technology, then that is allowed. This is what initially happened with the rolled up dimensions in M theory -- the instrumentation was too crude to detect it.

 

It is what also happens if you postulate that a deity influences evolution be introducing specific mutations. The background of random mutations is so high that, if a deity introduced a few particular mutations to drive evolution toward a specific goal, we wouldn't be able to detect that interference. BTW, ID can be, and has been falsified. ID isn't just that an intelligent designer used evolution to create. That's theistic evolution. Instead, ID is that some things must have been directly manufactured by an intelligent entity: irreducibly complex structures, complex specified information, whole species, etc.

 

So, that's one form of can't be detected: our tools simply won't pick it up but theoretically it does have an effect that could be detected.

 

The second form of "not detected" is an ad hoc hypothesis that has no other effect than keeping the hypothesis from being falsified. That is what the "aether" you are talking about is. Lorentz's aether did nothing but shorten the length by just the right amount so that the speed of light would measure the same in all directions. It has no other effect in the universe. And, as one of the sources I posted pointed out, even this doesn't work because it should be detectable.

 

Another ad hoc hypothesis (or series of them) are the mechanisms by which creationists propose that fossils were sorted by the Flood such that they form a series that mimics evolution. Each mechanism, by itself, has refutations, but the ad hoc hypothesis is put out that there are exceptions to the process. Exceptions that give us exactly what we see but that have no other effect.

 

lucaspa: Physicists may "strive for aesthetics" but that doesn't mean they decide the validity of a theory on its aesthetics.

 

Did I ever say that?

 

Yes, your original statement was "Physicists do evaluate theories in part based on simplicity." Evaluate = decide which is valid.

 

Given two theories that are indistinguishable mathematically but are very different in formulation (i.e., the underlying axioms), which would you prefer?

 

I wouldn't prefer either. I'd wait for data to establish which is correct. And from the sites I have found, LET and SR are not "indistinguishable" in their results.

 

I submit again that you are confusing "prefer" with accurate. When you get to deciding what the universe is based on what you prefer, you are violating the basic principles of scientific methodology:

"...what we learned in school about the scientific method can be reduced to two basic principles.

"1. All our theory, ideas, preconceptions, instincts, and prejudices about how things logically ought to be, how they in all fairness ought to be, or how we would prefer them to be, must be tested against external reality --what they *really* are. How do we determine what they really are? Through direct experience of the universe itself." Kitty Ferguson, The Fire in the Equations, pg. 38.

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Lucaspa---This is not correct. SR doesn't know about gravity, only GR does.

The source says differently.

It does not! Do you read the links or post or just post a link and it interpret it whatever way you want? The word "gravity" is used twice in your .edu link, http://www2.slac.stanford.edu/vvc/theory/relativity.html. Here is the second usage:

Note that Einstein's General Theory of Relativity is a separate theory about a very different topic -- the effects of gravity.

Pleasem stick to biology. You appear to be quite competent in that arena.

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...

Yes, your original statement was "Physicists do evaluate theories in part based on simplicity." Evaluate = decide which is valid.

 

Notice the "in part" there. Given two indistinguishable theories, the one that makes less assumptions and is more elegant is preferable to the other. Therefore, they are evaluated in part on their elegance and simplicity, but that need not interfere with experimental data.

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The source says differently. It is a .edu site: an academic institution with a physicist talking. You are going to have to do better than simple denial.

 

Ummm... I AM a physicist?

 

But, in trying to evaluate the accuracy or truth of 2 theories, we absolutely do NOT think the simpler is correct.

 

Take a poll of physicists and ask them if they believe in a higgs or in technicolor, and then ask them why. The two answers are both possible, as we haven't observed the higgs sector yet. The consequences of the two theories are the same for the low energy data. But only a handful of people in the world think that technicolor is right, because the higgs is much simpler.

 

lucaspa---I think perhaps you are coming from a different world. Aparently you're a biologist of some ilk. Maybe what you say is true in your field, but I can say, without a doubt, that in MY field (physics), simplicity is the deciding factor when it comes to two different descriptions of nature.

 

I didn't say it wasn't "elegant", I said it was not the simplest equation. The math is much more complicated. Now you are taking my point: use Feynman's equations because that is what the electron actually does, even tho they are not simple.

 

There is a simpler way to do quantum field theory calculations than Feynman path integrals???

 

Please show me. They are a bitch to do.

 

Oh, wait. Have you ever calculated a cross section using Feynman's path integrals? Radiative corrections to electron-positron scattering? The anomalous magnetic moment of the electron? Muon decays? Proton decays?

 

This is what initially happened with the rolled up dimensions in M theory -- the instrumentation was too crude to detect it.

 

You can save your lectures---I am writing a PhD on curled up dimensions.

 

lucaspa---You and I are of the same opinion of intelligent design, this much is clear. But you are not right about the way we select theories, at least in physics. I think you are outside your area of expertise, I think.

 

``I think that when a physicist talks about things that aren't physics, he's just as dumb as the next guy.'' ---Feynman

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getting back to the original topic......

 

In many advanced textbooks about evolution it is often claimed that evolution is a change in the frequency of the genes. But this simply is fallacious. If evolution were true it certainly would produce a change in the ratio of the types of genes which were present, because it would be adding new genetic information which previously did not exist. But the converse of this is not necessarily true. You can change the gene frequency or the ratio of the genes that are already present as much as you like, but unless you add new genes you won’t get evolution.

 

In evolutionary textbooks it is common to see the two forms of the English peppered moth (Biston betularia) being used as a ‘proof’ of evolution at work. There are two forms of this moth. One is jet black, the other (more common) has a sooty or peppered colour scheme. Soot-covered trees during Britain’s industrial past were an excellent camouflage for the black variety, whereas the peppered form stuck out like the proverbial wart on a prune and was easily picked off by the birds. Hence, for a time the black form of the moth was favoured. Its population increased, while the number of peppered individuals waned. The effects of the gene for blackness were favourable to the moth and thus moths whose genes expressed the black colour were seen much more commonly—the effect of the black genes was seen more frequently. This means that the number of genes for blackness began to increase and the number of genes for peppered colour began to reduce. Obviously, the ratio of genes was changing. But there were no new genes. There were black and peppered genes at the start, and black and peppered genes at the end.

 

Another simple experiment will help clarify the point that changing the gene frequency is not the same as producing evolution.

 

Obtain multiple copies of the back page of both an early and a late edition of an evening newspaper. These pages of information represent the genetic information in the two forms of peppered moth. The information printed on both versions of the back page will be very similar. Probably only the stop press and one or two minor items will be altered, but this is enough to make them two different and unique sets of information.

 

If we now make multiple copies of the late edition’s back page but keep only the original single copy of the early edition’s back page, we have increased the frequency of the later edition’s information. Note carefully that we have done nothing whatsoever to alter the total amount of unique information. It would not matter if we made a million copies of both editions of the back page; we would still have only two pages of unique information. The multiple copies are merely that-mere copies, mimics. They do not add any new information. To obtain increased information (rather than just an increase in the frequency of existing information) is far more complicated. It would entail journalists researching a new story, layout people formating it up, so as to yield a unique back page full of new information. You could not get new information without intelligent design.

 

Evolution, if it were to occur, would require the creation of completely new genetic information. Changes in living things, such as the colour distribution of the peppered moths, show an interesting alteration in colour-gene frequency, but they offer nothing at all to support the notion of evolution (that is formation of new genetic information).

 

Conclusion

Natural selection certainly can produce changes in gene frequency, but neither natural selection nor any changes in gene frequency will automatically produce evolution. They most certainly have not been observed doing so.

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creato,

 

You have to use the same definitions as everyone else. What you appear to be doing is using your own definition of evolution, and then complaining that everyone is using it incorrectly.

 

evolution is not synonymous with speciation, for example

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Conclusion

Natural selection certainly can produce changes in gene frequency, but neither natural selection nor any changes in gene frequency will automatically produce evolution. They most certainly have not been observed doing so.

I shall set aside swansont's comments on your faulty definition of evolution. (He is correct, but for the sake of discussion I shall accept your definition.)

You are absolutely correct. Natural selection will not produce evolution in the sense that you mean it. However, natural selection acting on genetic changes arising from mutations will most certainly result in evolution. i.e. Natural selection works in combination with novel heritable variations arising from changes in the organism's germinal DNA to deliver evolution.

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I shall set aside swansont's comments on your faulty definition of evolution. (He is correct, but for the sake of discussion I shall accept your definition.)

You are absolutely correct. Natural selection will not produce evolution in the sense that you mean it. However, natural selection acting on genetic changes arising from mutations will most certainly result in evolution. i.e. Natural selection works in combination with novel heritable variations arising from changes in the organism's germinal DNA to deliver evolution.

 

Just a supplement: It's not just "mutation" that brings about genetic changes but recombination during meiosis as well. Mutation gets a lot of credit, but it's really recombination that's responsible for most of the variation in a sexually reproducing species from generation to generation.

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If you look at the DNA, a genetic mutation does not necessarily imply the entire gene has totally changed, nor a brand new gene or gene train has been inserted, such as by a virus. A mutation can simply be one base pair that is incorrect. The protein that is made, might now have one animo acid different. If it so happens this amino acid is at the active site on an enzyme, then the enzyme's entire chemical reaction may change, since it will now have to bind something else. If this enzyme is in the middle of a train of enzymes, needed to make a very specific molecule, one of the precursors cannot be made and another chemical begins to flow to that enzyme. So there is a backlog and something new in the cytoplasm. The DNA reacts to this change, sort of like something has enterred the cell. This may cause genes to unpack. These alters the protein grid, such that during the next cell cycle, the two daughter cells begin differently. It is a ripple affect, where even a little chaos, begins a non-steady state, that culminates in a brand new steady state, i.e., evolution. Once it makes up its mind, the cellular system has lowered energy, due to the higher level of molecular efficiency being restored, i.e., removes all the backlog.

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:eyebrow: Man, it takes a lot of faith to belive evolution

 

Just a supplement: It's not just "mutation" that brings about genetic changes but recombination during meiosis as well. Mutation gets a lot of credit, but it's really recombination that's responsible for most of the variation in a sexually reproducing species from generation to generation.

 

Mutations nearly always cause mistakes(99.9999%) They can't be used support an evolving of one thing to another

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:eyebrow: Man, it takes a lot of faith to belive evolution

Friend, seriously. Please. It's not a war. It's about disregarding the most robustly supported proposal ever. It's not about a battle between religion and science, it's about the advancement of all life on our planet, and how a failure to think critically can lead to a failure to survive. It really is simple. It's not about faith. If you think it is, then that's okay, but please go ahead and take last year's flu vaccine so there's more of this year's for the rest of us.

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:eyebrow: Man, it takes a lot of faith to belive evolution

 

That depends on whether the universe is infinite or not. With infinite universe the math works quite differently...

 

Mutations nearly always cause mistakes(99.9999%) They can't be used support an evolving of one thing to another

 

Mutations are mistakes. Most of them are bad, the key word being most.

 

Friend, seriously. Please. It's not a war. It's about disregarding the most robustly supported proposal ever. It's not about a battle between religion and science, it's about the advancement of all life on our planet, and how a failure to think critically can lead to a failure to survive. It really is simple. It's not about faith. If you think it is, then that's okay, but please go ahead and take last year's flu vaccine so there's more of this year's for the rest of us.

 

Now that's and exaggeration; surely the laws of physics are far better tested than evolution. The biggest problem with the evidence for evolution is the fanatics on both sides tend to exaggerate so it is hard to believe anyone even if they say they are scientists. That's also the problem with global warming btw.

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Hey Creato what your saying isn't very reliable. For one thing they're not going to take the bible, which can't be tested scienctifically as a source. I'm a creationists, but when it comes to evolution they got some interesting points on it. That quite frankly are very hard to find any thing against the source. However, I do believe that there's errors at the site talkorigins. They need to stop giving it as their only source. Along with Wikipedia.

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The biggest problem with the evidence for evolution is the fanatics on both sides tend to exaggerate so it is hard to believe anyone even if they say they are scientists. That's also the problem with global warming btw.

The way people present the data and the passion they use when doing so has no relevance to it's validity. This applies both to evolution by natural selection and anthropogenic global climate change. When one looks at all of the evidence available to us on these issues and determine that it's "not conclusive" is to put ones fingers in their ears and close their eyes like a toddler... In other words, it's both childish and foolish.

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Introduction to Wikipedia: -> http://en.wikipedia.org/wiki/Wikipedia:Introduction

 

(But I think it's still quite good and in most times accurate.)

 

Yeah, I do, but when I have to do research my college professors don't want me using it as a source. It has a too high of a chance for error, but sometimes it's the good source you can find. I've read several articles where there was a million of citations missing.

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The way people present the data and the passion they use when doing so has no relevance to it's validity.

 

True, but it has a huge effect on its credibility. Conflicts of interest and bias can eliminate the presumption of good faith that usually allows us to accept a scientist's conclusions without going through it with a fine-tooth comb and a microscope (for people in a different area of study, that is.). This

presumption of good faith is what allows science to advance, otherwise you would have to repeat every experiment ever performed yourself.

 

This is also why people have to take results about smoking commissioned by tobacco companies with a grain of salt.

 

This applies both to evolution by natural selection and anthropogenic global climate change. When one looks at all of the evidence available to us on these issues and determine that it's "not conclusive" is to put ones fingers in their ears and close their eyes like a toddler... In other words, it's both childish and foolish.

 

But both sides are lying and exaggerating, which makes it difficult to tell who's data and who's conclusions to accept. The whole point is that there is so much data that no one can look at it all, and people are lying and exaggerating so you can't just take their word. For these two issues, the immense timescales and indirect nature of the data added to the politics makes it difficult to make a clear decision.

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For these two issues, the immense timescales and indirect nature of the data added to the politics makes it difficult to make a clear decision.

 

How you perceive the credibility still has no impact on the validity of the data. Also, you are picking and choosing what data you look at. The timescales comment you made fails when viewing fruit flies, and also when we have historical climate records.

 

The decision is easy... at least in my book. I concede that there are a lot of politics and agenda pushing, but I'm fine with an agenda that is trying to save life as we know it. If you're going to choose anything, choose that, and err on the side of caution.

 

Per evolution by natural selection, not believing that is dumb. That's my opinion, and I stand by it.

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