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Comment by breck | Hacker News Reader

Any chance you could provide some analogies to someone with deep computer expertise who wants to learn quantum physics?

Is QFT analogous to binary? Everything builds up from QFT?

There are no good analogies I know of. I wouldn't say it's like binary in any way, but I also wouldn't say that that everything builds up from binary in CS. There is really no particular relation to (or benefits of having) computer expertise.

Two recent popular books about QFT are:

Matt Strassler’s Waves in an Impossible Sea (no math, just hand-wavy analogies): https://www.amazon.com/dp/B0CB3LZXR9/

Sean Carroll’s Quanta and Fields (tries to give you a basic understanding of the actual math): https://www.amazon.com/dp/0593186605/

Helpful. Just got Quanta and Fields. Thanks!

Would it be apt to say QFT is like ECS?

Elastic Container Service? Um, no. Or did you mean something else?

Entity-Component-System

OK, well, that makes a little more sense. But the answer still seems to me to be a pretty obvious "no". ECS is an engineering methodology. QFT is a mathematical formalism that combines quantum mechanics and special relativity. It's really apples and oranges.

All of the complications and complexity in QM/QFT are from doing calculations that map to the extremely coarse-grained boring low-energy reality we spend all of our lives in. If you ignore that, the underlying math is exceedingly trivially formulated. It's like 2 powerpoint slides to show what CUDA arrays and ops are needed to underpin a quantum field theoretic calculation of quarks and gluons inside a proton for example.

Unfortunately you're probably not going to be satisfied with that, at some point you need to connect these simulations to real measurable parameters and this is exceedingly non-trivial :/

Starting from the other end, pure old-school undergrad quantum mechanics is really the easiest way to connect to measurable quantities and this is why it's used in all of engineering, quantum optics etc. It just provides the right amount of detail.

Only if you ignore calculations around quantum collapses, or whatever your favorite interpretation calls those. We don't yet know how to calculate when those will happen, so that is by far the most complex task since it hasn't been solved yet.

I suspect that solving those collapses is key to connecting quantum mechanics to relativity, seems like a much more reasonable place to look than to invent even more fields like string theory does.

Well, there are no experiments that have been done or even suggested that requires this. Except maybe the Wigner's Friend thought-experiments? They seem pretty interesting and strikes to the center of the evolution discontinuities issues.

But for all normal practical purposes you don't need to solve that and can ignore it (which is both a blessing and a curse of course)

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