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Organisms might be quantum machines

bbc.com

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Re: Organisms might be quantum machines

#51

Post by sriku »

fizixer wrote: post #17
danbruc wrote: post #5

Tl;dr Biology is applied chemistry, chemistry is applied quantum physics and in some cases chemistry is a leaky abstraction and does not perfectly explain what is going on in organisms. Three examples - photosynthesis being more efficient than expected, birds sensing Earth's magnetic field by an unknown mechanism and a lack of understanding how olfaction works in detail - are presented but besides that there are no n…

> ... chemistry is a leaky abstraction ... Well I second you on that. Even stronger: All of (theoretical) science is a leaky abstraction. When an area is new, people are doing the spherical-cow-approximation willy nilly. After it gets established, corner cases start to surface. Incidentally, theoretical physicists are the masters of creating spherical-cow-approximations and leaky-abstractions. They're always going fo…

A meta spherical cow?

Re: Organisms might be quantum machines

#52

Post by sriku »

danbruc wrote: post #5

Tl;dr Biology is applied chemistry, chemistry is applied quantum physics and in some cases chemistry is a leaky abstraction and does not perfectly explain what is going on in organisms. Three examples - photosynthesis being more efficient than expected, birds sensing Earth's magnetic field by an unknown mechanism and a lack of understanding how olfaction works in detail - are presented but besides that there are no n…

Good summary. Classical physics is not good enough for chemistry. So why are we surprised that without a quantum foundation, biology cannot function at all?

OTOH, we have a theory that classical computation adequately accounts for intelligence. Finding an unavoidable quantum route that nature has picked would certainly be interesting, despite that quantum Turing machines are also classically computable (I think).

Re: Organisms might be quantum machines

#53

Post by Dylan16807 »

flukus wrote: post #45
jheriko wrote: post #27

quite interesting, but its a bit confused... and its not exactly a revelation that processes involving molecules or particles are best explained by quantum effects. this is precisely where quantum physics came from - trying to explain these things. "The wet, warm, bustling environment of living cells is the last place you might expect to see quantum events." stuff like this is misleading imo. its exactly the sort of…

>stuff like this is misleading imo. its exactly the sort of place you expect to see quantum effects - because its in the universe and at the appropriate scale. Isn't this a few orders of magnitude above where you'd expect to see quantum effects?

We're not talking about entire cells having quantum fluctuations. Just single molecules within them; exactly the scale where you expect such oddities.

Re: Organisms might be quantum machines

#54

Post by flukus »

Dylan16807 wrote: post #53
flukus wrote: post #45

Earlier quoted context omitted.

>stuff like this is misleading imo. its exactly the sort of place you expect to see quantum effects - because its in the universe and at the appropriate scale. Isn't this a few orders of magnitude above where you'd expect to see quantum effects?

We're not talking about entire cells having quantum fluctuations. Just single molecules within them; exactly the scale where you expect such oddities.

That makes more sense, thanks.

Re: Organisms might be quantum machines

#55

Post by Dylan16807 »

CyberDildonics wrote: post #40
saskurambo wrote: post #4

This can open new research also on how works for example homeopathy and acupunture?

Do you know what people call homeopathic medicine that is proven to work? Medicine.

You're thinking "alternative".

Homeopathy is a very specific thing, where you take a substance with a bad effect and dilute it so much there's none left, in an attempt to cause the opposite effect, with more dilution being better.

Re: Organisms might be quantum machines

#56

Post by ddt_Osprey »

Terr_ wrote: post #23
mixedmath wrote: post #2

Only somewhat related: I'm currently reading Anathem by Neal Stephenson. I'm nearing the end of the book, and the concept that human brains might use quantum processes in the decision-making process is a very important and prevalent idea in the novel. [Although he takes some artistic license --- it is only a novel, afterall]. So I've been thinking, at least passively, about organisms being quantum machines quite a bi…

My cynical prediction is that if quantum-effects are part of the brain, it will only be in a practical, philosophically-boring way. So they may be essential to basic plumbing shared by many species, but not otherwise a game-changing factor for "consciousness" or "intelligence".

Perception in humans seems capable of grasping data sets with billions of pieces of information each second, and distilling it all down to intuition.

All this information is serialized onto pretty much 5 channels (excluding things like one's sense of balance, or the awareness of how your body is posed), all streamed concurrently.

Sounds like a recipe for high bandwidth consumption. Many cycles per second.

Based on this, I'd wager we (and our perception of self) only exist in the ether between our body's neurons.

Re: Organisms might be quantum machines

#57

Post by flukus »

pdonis wrote: post #46
flukus wrote: post #45

Earlier quoted context omitted.

>stuff like this is misleading imo. its exactly the sort of place you expect to see quantum effects - because its in the universe and at the appropriate scale. Isn't this a few orders of magnitude above where you'd expect to see quantum effects?

> Isn't this a few orders of magnitude above where you'd expect to see quantum effects? No. Chemistry itself is fundamentally dependent on quantum effects; quantum effects determine the structure of atoms and molecules, how they combine, and how much energy is involved in those processes. That's true whether the processes are taking place in living bodies or not. My reaction to this article is basically the same as j…

I thought chemistry operated at a higher level, as in it doesn't care how or why a atoms are structured they way they are, they just deal with the results at a higher level of abstraction. Is this incorrect?

Re: Organisms might be quantum machines

#58

Post by eli_gottlieb »

sriku wrote: post #52
danbruc wrote: post #5

Tl;dr Biology is applied chemistry, chemistry is applied quantum physics and in some cases chemistry is a leaky abstraction and does not perfectly explain what is going on in organisms. Three examples - photosynthesis being more efficient than expected, birds sensing Earth's magnetic field by an unknown mechanism and a lack of understanding how olfaction works in detail - are presented but besides that there are no n…

Good summary. Classical physics is not good enough for chemistry. So why are we surprised that without a quantum foundation, biology cannot function at all? OTOH, we have a theory that classical computation adequately accounts for intelligence. Finding an unavoidable quantum route that nature has picked would certainly be interesting, despite that quantum Turing machines are also classically computable (I think).

>OTOH, we have a theory that classical computation adequately accounts for intelligence. Finding an unavoidable quantum route that nature has picked would certainly be interesting, despite that quantum Turing machines are also classically computable (I think).

I don't think we have a foundation for classical computation without thermodynamics, which is a classical theory whose ultimate foundations probably require quantum information theory.

Re: Organisms might be quantum machines

#60

Post by pdonis »

flukus wrote: post #57
pdonis wrote: post #46

Earlier quoted context omitted.

> Isn't this a few orders of magnitude above where you'd expect to see quantum effects? No. Chemistry itself is fundamentally dependent on quantum effects; quantum effects determine the structure of atoms and molecules, how they combine, and how much energy is involved in those processes. That's true whether the processes are taking place in living bodies or not. My reaction to this article is basically the same as j…

I thought chemistry operated at a higher level, as in it doesn't care how or why a atoms are structured they way they are, they just deal with the results at a higher level of abstraction. Is this incorrect?

> I thought chemistry operated at a higher level

"Chemistry" as you're using the term here is a name for a set of models made by humans, not something in actual atoms and molecules. The atoms and molecules don't know that they're supposed to be doing "chemistry" instead of "quantum stuff".

When I say chemistry is fundamentally dependent on quantum effects, I mean the things atoms and molecules actually do would be impossible without quantum effects. The very existence of atoms depends on quantum effects; in a purely classical world atoms would be impossible. The chemical properties of atoms--their valences, for example--require quantum mechanics to explain.

Often in human models of chemistry, the details of how things like valences of atoms are produced from quantum effects are left out. But that doesn't mean quantum effects aren't being seen when we observe atoms with particular valences, for example. It just means the details aren't explicitly present in those models.

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