Falter: Every Birth is a Statistical Impossibility

Science

(Jon Garvey) #29

Amen - and that’s why to say something like “events governed by a probability distribution” is entirely misleading. Events produce a probability distribution, and a probability distribution has no causal properties, being a deduction from results.


(Bill Cole) #30

I agree. The probability distribution may tell you something about the cause of the event.


(Jon Garvey) #31

Can you expand on that Bill? In itself the probability distribution is just numbers, though I guess deductions made from that might give some clues. For example, if the results from some submicroscopic dice show exactly 6 states, smoething of the nature of the hidden system could be deduced.


(Bill Cole) #32

A simple example would be observing the point plot of 1000 die rolls that is claimed to be simply shaking and rolling die. We would expect an even distribution around all six numbers given simply shaking the die and throwing it. If we instead we saw instead a bell curve with a peak at the number 3 that would tell us that there was more to the process than simply shaking the die and throwing it.

The shape of the curve can either reject or validate the cause of the distribution we are observing being simply shaking and rolling the die.


(Jon Garvey) #33

OK - though of course such a bias would require us to investigate whether the problem was in the dice, in the rolling, or both (or in our counting, I suppose).


(Bill Cole) #34

I agree


#35

Agree that it is one of humans greatest accomplishment to understand probability and statistics. A very good book on how we did it is here:


(Jon Garvey) #36

A better book on what we actually discovered is:

Uncertainty - William Briggs


(Chris Falter) #37

Hi Jon,

My point is that quantum events are not the only form of indeterminancy. Physicists have identified 3 regimes: classical, chaotic, and quantum. And it is entirely possible that the occurrence of mutations belongs, in part or in whole, to the chaos regime. If so, this would imply that your binary view of the possibilities (biological events are in theory 100.0% predictable with sufficient data and models vs. quantum indeterminancy) is too reductionist.

I read a couple of articles for background on the chaos regime and its relationships to the others that seemed helpful. I share links below.

Being neither a biologist nor a physicist, I have no idea of any work being done at the intersection of biology and physics that would classify the physics regime of DNA transcription. I would love to learn more from anyone who knows the literature.

Links to popular articles on the 3 physics regimes:

EDIT: The impression I have is that it is a faith claim to believe that the chaos regime must eventually reduce to either the classical or the quantum regime in the presence of sufficient data.


(Jon Garvey) #38

I do know that John Polkinghorne is said to have backed off from chaos as an alternative “guidance” mechanism to quatum uncertainty, probably because most physicists believe chaos is classical.

The problem of chaotic uncertainty is that, because miniscule inaccuracies of human observation are magnified, we are radically unable to predict their outcomes. That’s why they tend to be modelled and statistical evaluations made of the aggregate results. Such observational limitations, though, are again epistemic rather than ontological - they would not apply either to God or some demon with powers of exact measurement.

One really interesting facet of that (to me anyway) as regards both divine and human interaction with the world, is how many natural systems are operating on the edge of chaos. In effect, this makes them relatively easy to change, whilst being stable within limits. One classic example of that is the solar system. Another is the weather.


(Chris Falter) #39

As far as I can tell, Jon, this is a faith statement that physicists might not agree with.

But again, I am neither a physicist nor a biologist. I have studiously followed the Bard’s maxim, “Neither a physicist nor a biologist be.” :wink:

This is a very good point. Thanks for sharing it.


#40

According to a paper I found on DNA polymerase from E. coli, there is a loose fit between the incoming nucleotide and the active site of the enzyme. This is responsible for a large chunk of the substitution mutations:


(Jon Garvey) #41

Not sure how, Chris, since I learned it from physicists. More a question of what kind of thing might conceivably exist to make chaotic events indeterminate (that is, to posit indeterminate forces is itself the faith-based statement unless one has evidence).

Take a simple limiting case: something balanced on the point of a pin. Extremely unstable: the most miniscule vibration or faint breeze would make it fall, but which way it will fall is unpredictable. It’s a chaotic systrem, but conceptually simpler than a hurricane or a three-body problem in gravity.

However, if we suppose it to be finely balanced but free of every specific force such as a puff of wind from the north, or a slight earth tremor from the southwest, would we expect it to sponteously fall in some random direction? Why? What force would make it do so, and why would it be indeterminate, unlike ever other force we know?


(Timothy Horton) #42

Been 3 days now. Any updates on the big surprise?


(S. Joshua Swamidass) #43

I know! Not yet not in my control. They are dragging feet. With all the anticipation, hope you aren’t disappointed.


(John Mercer) #44

A third is biology.


(Jon Garvey) #45

Yes indeed.


(Chris Falter) #46

Hi Jon,

What I have gleaned from physicists is that a characteristic of chaotic systems is that tiny changes in initial conditions yield huge changes in outcomes. This characteristic does not necessarily imply that better knowledge of initial conditions could allow physicists to treat such systems in a conventional manner with highly predictable results, or even that better knowledge of initial conditions is theoretically attainable.

Sure. To posit determinate forces in chaotic systems is also a faith-based statement in the absence of evidence.

Please note I am not claiming that there is no such thing as a basically deterministic outcome: An apple that falls from a tree will strike Sir Newton on the head if he is sitting underneath. There is a deterministic regime in physics.

What I am suggesting is this: Just as many phenomena in the quantum regime can never be deterministically predicted by a human, it is possible that many phenomena in the chaos regime can never be deterministically predicted. How could this be? Here are 2 ideas that might apply to some chaotic systems:

  • Because it requires energy to gather information, it could be that not enough energy is available to gather the data required to make a deterministic prediction.
  • It could be that the infinitesimal changes that yield different outcomes can become so infinitesimal that Planck scale is reached, and all ability to predict deterministically is lost.

Since neither one of us is a physicist, I don’t want to make a big deal of our disagreement. And I would welcome the input of @physicists who can shed any more light on this discussion.

Thanks, and have a great day,
Chris


(Jon Garvey) #47

Chris, I agree that many phenomena in the chotic realm cannot be humanly predicted, for the reasons you state below (though I may wish to examine the second more closely, wrt to infinitesimals and to quantum indeterminacy).

There is a need, though, to distinguish carefully (when speaking in a theological context) between unpredictability and non-reproducibility on the one hand, and indeterminacy on the other (and perhaps also between physical indeterminacy and divine indeterminacy, if that is a coherent distinction).

In this discussion I’m most interested in physical indeterminacy, and have a few thoughts on examining a chaotic system critically to do so. But it will take a blog-length discussion, so I aim to do it on the Hump, but will post a link here so the discussion can continue.

It’ll take a day or two, though, as I’m away into the weekend.


(Jon Garvey) #48

OK @Chris_Falter Chris (and whoever else).

Back from Warwickshire (Straford-on-Avon’s looking a pretty as ever), so a piece on chaos posted on the Hump. Hopefully it’s determined but not too predictable.