Saturday, December 16, 2006

quantum evolution

On several occasions in discussions about life etc friends have mentioned the theory that quantum mechanics dictates the way our cells work. In the past I have not been convinced. However this site has a very well written description of the theory which is very compelling.


Anonymous said...


This is just embarrassing. Quantum mechanics determines how everything works, and there's no evidence that there is anything magic about life, or that cells don't work according to normal, physical rules.

Next time you link to some weird proposal like this, look for some kind of testable prediction: what would be true under this explanation and not under conventional explanations? What could show either that the new theory is false, or that it explains something better than conventional theories?

Anonymous said...

What anonymous said.

The adaption to different sugars is a well known and established experiment dating back a long time.

No one felt the need to explain why the mutations that digests available food prosper, and it is almost impossible to establish if any of the bacteria underwent useless mutations to digest sugars that weren't available because they failed to thrive through lack of food. I guess if the mutations that favour success have some sort of decoherence you would have to ask why don't all replicating cells immediately produce the correct mutation. I bet if you look the succeeding organisms are all from one mutation (usually, with enough cells one would expect different mutation to do the same thing to happen several times in any given period).

Quantum decoherence is a tricky concept to think about. But applying it to any problem one doesn't have a solution to (like Penrose did in the Emperors New Mind to consciousness), is no different to saying "God did it".

Mycoplasma maybe fairly simple organisms compared to humans. But the ones around now have had to survive 3 and a bit billions years of evolutionary competition and change, and probably bear as much relationship to the organisms that started life on earth as we do.

RNA is usually assumed to the be more similar to the type of organism we all started from, so viruses are probably a closer fit than mycoplasmas. Viruses similarly though come in a lot of different sizes and complexity, some of which have been competing with immune systems for about a billion years, and so aren't much like the origin of life either.

Guess there is an anthropic principle lurking in there as well, I mean we wouldn't be discussing this in all the universes where life didn't get complex. But the anthropic principle is just an example of how bad humans are with probability. We know the probability of sophisticated life on earth developing, it is 1.0, and nothing we learn about how fragile, or robust, the process required can alter that probability now. We may discover procedures that greatly facilitate that process, which seem plausible, or we may discover through genetic archeology that life on earth did it the hard way.

chele said...

Shouldn't the line that reads "At the macroscopic level we see patterns and order, but at the molecular level there is only chaos." say "...but at the molecular level we see only chaos."?