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Quantum weirdness is everywhere in life

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Re: Quantum weirdness is everywhere in life

#71

Post by titzer »

kordless wrote: post #52
titzer wrote: post #43

Earlier quoted context omitted.

Reading their abstract makes me cringe. "The principle that mutations occur randomly with respect to the direction of evolutionary change has been challenged by the phenomenon of adaptive mutations. There is currently no entirely satisfactory theory to account for how a cell can selectively mutate certain genes in response to environmental signals. However, spontaneous mutations are initiated by quantum events such a…

You say it makes you 'cringe', yet you offer no substantial argument to why you are fearful of their hypothesis. Saying things like "BS" and "WTF" is a weak attempt at hacking biases, and usually attributed to dissonance. I don't accept biased arguments as truths. Quite the contrary, I see them as indicators of an unresolved argument. I'm not afraid of their hypothesis and I welcome the truth, however weird it may be…

There are countless examples of mutations that are single letter transcription errors, insertions, duplications, recombinations. Quantum effects and superpositions aren't necessary to explain those. I wonder what extra explanatory power this theory adds over more conventional chemical models of DNA and what evidence exists that quantum effects are anything more than negligible.

Re: Quantum weirdness is everywhere in life

#72

Post by williamjennings »

n4r9 wrote: post #66
williamjennings wrote: post #39

Earlier quoted context omitted.

My opinion is that the Copenhagen interpretation does not contradict DeBroglie in terms of nuclear chemistry, but solely thermodynamics. The Copenhagen interpretation makes a leap of faith with the Born Rule as it is based on Maxwell-Boltzmann statistics. The work of t'Hooft is a more modern alternative for ensembles where the outcome is stochastic, rather than probabilistic. Photosynthesis has that property, as do m…

Not sure what you mean by "contradict". Certainly you won't easily find experiments for which the two offer different predictions. They are very different in terms of their ontology though: DeBroglie states that particles have definite positions and momenta at all times whereas Copenhagen does not.

Most of the contradictions arise as epistemological forks in the context of molecular spectroscopy with nuclear decay events. Thusly, it is a question of whose theories to use, and the Born rule is moot when the distribution of particles is not gaussian.

DeBroglie himself states that matter waves propagate according to a defined distribution; whereas Copehagen interprets that they are probabilistically distributed. In the former case there is a stochastic process, whereas it is only a random process in the latter case.

Re: Quantum weirdness is everywhere in life

#73

Post by effie »

williamjennings wrote: post #39
n4r9 wrote: post #32

Earlier quoted context omitted.

I meant "rigorous and comprehensive" to include "representative of the entire quantum community". That poll was conducted at a single conference and had 33 participants. The bias inherent in this approach can be seen when the same poll was conducted at two other conferences: http://arxiv.org/abs/1303.2719 http://arxiv.org/abs/1306.4646 In both cases, de-Broglie Bohm interpretations ruled the day. As the abstract of t…

My opinion is that the Copenhagen interpretation does not contradict DeBroglie in terms of nuclear chemistry, but solely thermodynamics. The Copenhagen interpretation makes a leap of faith with the Born Rule as it is based on Maxwell-Boltzmann statistics. The work of t'Hooft is a more modern alternative for ensembles where the outcome is stochastic, rather than probabilistic. Photosynthesis has that property, as do m…

> The Copenhagen interpretation makes a leap of faith with the Born Rule as it is based on Maxwell-Boltzmann statistics.

The Born rule was introduced in Born's paper on description of a scattering experiment with help of the \psi function that is a solution of Schroedinger's equation. Maxwell-Boltzmann statistics had nothing to do with it.

Re: Quantum weirdness is everywhere in life

#74

Post by effie »

coverup wrote: post #58
rogerbraun wrote: post #17

It's always a shame when the Copenhagen interpretation of quantum mechanics is presented as how reality works. Most of the perceived weirdness of QM comes from the leaps of faith required to make the Copenhagen interpretation work.

It's a shame when physics is presented as how reality works! Rather than what it is: our best model.

Exactly. Many people seem to fall into trap of regarding established theories of theoretical physics as some ultimate truths about the world, instead of as currently used useful models which are necessarily imperfect simplifications of things. It is depressing to see science, which has contributed to exposition of fallacy of church teachings during the past centuries and help enlighten people, to be on its best way to becoming a church full of dogma and blind followers itself.

Re: Quantum weirdness is everywhere in life

#75

Post by ild »

dekhn wrote: post #46
ild wrote: post #24

Earlier quoted context omitted.

Folding has nothing to do with DNA.

DNA and RNA both also fold. This is an approximation: http://mfold.rna.albany.edu/?q=mfold/dna-folding-form The underlying quantum chemistry (which doesn't need to specifically invoke coherence or tunneling) is required to get truly accurate results. Classical approximations aren't sufficient to measure really subtle energy differences between folded forms.

I am not talking about RNA. I am talking strictly about. The way DNA stores information has nothing to do with the way it is folded. Proteins and some types of RNA require proper folding to function, DNA does not.

Re: Quantum weirdness is everywhere in life

#76

Post by ild »

sklogic wrote: post #33
ild wrote: post #24

Earlier quoted context omitted.

Folding has nothing to do with DNA.

DNA encodes the amino acid sequence. Quantum mechanics defines the folding. These two things combined determine the colour of your eyes, etc., etc. Encoding per se is meaningless without the folding. Also, the way how RNA polymerase work (i.e., transcription) is of quite a quantum nature too.

DNA needs to be _unfolded_ during transcription. Anyway, the information stored in DNA in a very much non-quantum nature.

> Also, the way how RNA polymerase work (i.e., transcription) is of quite a quantum nature too.

Proof?

Re: Quantum weirdness is everywhere in life

#77

Post by dekhn »

ild wrote: post #75
dekhn wrote: post #46

Earlier quoted context omitted.

DNA and RNA both also fold. This is an approximation: http://mfold.rna.albany.edu/?q=mfold/dna-folding-form The underlying quantum chemistry (which doesn't need to specifically invoke coherence or tunneling) is required to get truly accurate results. Classical approximations aren't sufficient to measure really subtle energy differences between folded forms.

I am not talking about RNA. I am talking strictly about. The way DNA stores information has nothing to do with the way it is folded. Proteins and some types of RNA require proper folding to function, DNA does not.

This is incorrect: DNA in the folded form of chromatin stores information. In particular, chromatin state is epigenetic and is used to deactivate many genes during the development process.

Further, even a duplex is a "fold" (coiled coils are a structural motif).

You're fixating on the A T G C base form of encoding; DNA contains a lot more information than just that, encoded in its quatenary structure.

Re: Quantum weirdness is everywhere in life

#78

Post by williamjennings »

effie wrote: post #73
williamjennings wrote: post #39

Earlier quoted context omitted.

My opinion is that the Copenhagen interpretation does not contradict DeBroglie in terms of nuclear chemistry, but solely thermodynamics. The Copenhagen interpretation makes a leap of faith with the Born Rule as it is based on Maxwell-Boltzmann statistics. The work of t'Hooft is a more modern alternative for ensembles where the outcome is stochastic, rather than probabilistic. Photosynthesis has that property, as do m…

> The Copenhagen interpretation makes a leap of faith with the Born Rule as it is based on Maxwell-Boltzmann statistics. The Born rule was introduced in Born's paper on description of a scattering experiment with help of the \psi function that is a solution of Schroedinger's equation. Maxwell-Boltzmann statistics had nothing to do with it.

Because thermodynamics at the time espoused normally distributed error as dictated by Maxwell-Boltzmann statistics; Born used a normalized wave function to solve Schroedinger's equation.

Thermodynamics and Linear Algebra have gotten more advanced, since then.

Re: Quantum weirdness is everywhere in life

#79

Post by kordless »

titzer wrote: post #71
kordless wrote: post #52

Earlier quoted context omitted.

You say it makes you 'cringe', yet you offer no substantial argument to why you are fearful of their hypothesis. Saying things like "BS" and "WTF" is a weak attempt at hacking biases, and usually attributed to dissonance. I don't accept biased arguments as truths. Quite the contrary, I see them as indicators of an unresolved argument. I'm not afraid of their hypothesis and I welcome the truth, however weird it may be…

There are countless examples of mutations that are single letter transcription errors, insertions, duplications, recombinations. Quantum effects and superpositions aren't necessary to explain those. I wonder what extra explanatory power this theory adds over more conventional chemical models of DNA and what evidence exists that quantum effects are anything more than negligible.

If we're simulated, this would be a spectacularly good way to get a bit of us out of this reality and into another one. It would also allow only a singleton instantiation of you, which is important if you care about those things. Over 70 percent of us believe we have a soul. That number is dropping.

Re: Quantum weirdness is everywhere in life

#80

Post by sklogic »

ild wrote: post #76
sklogic wrote: post #33

Earlier quoted context omitted.

DNA encodes the amino acid sequence. Quantum mechanics defines the folding. These two things combined determine the colour of your eyes, etc., etc. Encoding per se is meaningless without the folding. Also, the way how RNA polymerase work (i.e., transcription) is of quite a quantum nature too.

DNA needs to be _unfolded_ during transcription. Anyway, the information stored in DNA in a very much non-quantum nature. > Also, the way how RNA polymerase work (i.e., transcription) is of quite a quantum nature too. Proof?

Yes, the DNA encoded information is classic (please do not consider my comments as any kind of an endorsment of the OP article). But, as I said, this is only a half of the information you need to get any sensible predictions of the results. The rest is defined by folding, and it is very much quantum (heuristics aside).

> Proof?

I never heard of any polymerase simulation which did not involve computational quantum chemistry methods. Cannot even think of any possible classic approximation (again, heuristics aside - they're just masking the quantum nature of the underlying physics).

EDIT: as for transcription, do not forget about the operons. Theirs molecular mechanics is also very quantum.

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