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Comment by shoyer | Hacker News Reader

I recently finished my PhD on quantum effects in biology (my focus was on photosynthesis). This article and the many others like it are full of poorly substantiated hype.

Yes, quantum mechanics is important to some biological processes. But (1) many physicists in this field have blatantly ignored vital chemical and biological details when constructing their models and (2) it's not entirely clear who should be "surprised" by this sort of quantum entanglement, which is not that different from standard notions of chemical bonds.

Also note that this news piece is actually from 2010, and the preprint article it refers to (http://arxiv.org/abs/1006.4053) was never published in a peer-reviewed journal -- presumably because the authors couldn't get it past peer review.

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> Yes, quantum mechanics is important to some biological processes.

I'm not quite sure how to parse this statement. Wouldn't quantum mechanics underlie all biological processes?

The point is that, while quantum rules sit at the bottom of most macroscopic objects, quantum rules aren't important for most objects on an everyday basis. Similarly, if entanglement is important for explaining the behavior of DNA, that would be novel factual information.

Yes, exactly. You don't need to understand quantum mechanics to understand most biological processes (within the limits of our current knowledge). Biologists don't need to learn quantum mechanics.

that is not true at all. I'm engineering a better hydrogenase and had to explain marcus theory to the biology profs (i.e. all of them, since I work at a biology institute). Totally hopeless, because they didn't know quantum. Knowing quantum from chemistry, I taught the basic principles to myself in a few minutes.

He said most. Look at what the Anton CPU can do with just force fields and spring modeled bonds. They have found some cases where quantum matters, buy not all.

electron transfer is a basic concept in metabolism, my specific application notwithstanding.

it would have been more accurate for them to have said "nonclassical quantum mechanics".

Atoms aren't stable in a classical universe.

that's a nonsense phrase.

Saying "quantum rules aren't important for most objects" just isn't true. I understand what you're trying to say -- that we mostly use imprecise metaphors in place of what's really going on -- but that's a statement about our understanding, not reality.

For example, solids are "solid" largely because of the Pauli exclusion principle, which says that two fermions (such as electronics) can't occupy the same state at the same time. These effects are so familiar, and we explain them with simple words like "solid," that we forget that quantum mechanics makes it work. Without quantum mechanics, we'd fall through the floor.

How about "the higher-level abstractions of biochemistry encapsulate quantum-mechanical effects pretty well, and rarely leak"?

That's hitting the nail on the head that is - right there. But telling a pedant what they do or don't need to be pedantic about is a losing game

Per a comment down thread that without quantum effects we'd all fall through the floor. Yes. But I don't need to solve Shroedinger's equation every time I go for a walk. In the same way, Biologists don't always have to take into account quantum mechanical effects, but the times that they do are very interesting and worth hearing about.

I briefly scanned the PDF looking for "base stacking" because this seemed so analogous. The only mention of the phrase was in the title of a reference. It would have been nice for them to address this.

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