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Hey- can you please not post supercilious or sneering comments? It really poisons the ecosystem. What we want is curious conversation in which people share information. Putting others down who you think aren't as smart as you or others, and calling that "amusing", is definitely not what we're looking for—no matter how wrong they are or you feel they are. This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html.

If you know more than others, that's great—the best thing is to share some of what you know, so the rest of us can learn. Just please do it without swipes and putdowns.

https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...

There are many practical applications of quantum mechanics.

The one that I remember foremost is tunneling to (dis)charge the floating gates on flash memory transistors, but that just scratches the surface.

"Flash memory chips found in USB drives use quantum tunneling to erase their memory cells."

https://en.m.wikipedia.org/wiki/Applications_of_quantum_mech...

This I did not know:

"It even exists in the simple light switch. The switch would not work if electrons could not quantum tunnel through the layer of oxidation on the metal contact surfaces."

But does it flow through wires?

https://www.youtube.com/watch?v=bHIhgxav9LY

It collapses through chloroplasts!

https://www.scientificamerican.com/article/when-it-comes-to-...

Ironic that plastid-based life is so much more advanced than us, but we are the ones that ended up with (super)intelligence.

Is there something specific about oxidized metal that electrons need quantum tunneling to move through them? Why can't we just assume its normal conductivity?

Aluminum is extremely reactive, and the classic method of liberating this energy is through thermite reactions. Without the oxidation layer on aluminum, it would be an extremely hazardous substance.

"Breaking bad" covered this with an etch-a-sketch. Sometimes chemistry can be surprising.

https://en.wikipedia.org/wiki/Thermite

That's neat but I don't really follow. Why isn't the oxidation layer just a higher impedance material? Why is quantum tunneling required to explain a light switch?

While I do get what you're trying to say, it has to be said that many CS people have been exposed to Quantum Physics.

Quantum computing is an elective at every half-decent University.

To think that programmers have zero understanding beyond high school math is just ignorant.

At least for me and my classmates, we got a lot more wrong before we got right. Nothing is worse in this world than an undergrad fresh out of an intro quantum class with a neutered Schrodinger's equation and whatever nonsense pseudo-philosophy they picked up to deal with it. After taking a proper mathematical methods class you start to get the beginnings of an intuition for what's going on for quantum mechanics.

I agree. EPR states and Quantum teleportation gave us a reality check during our QC course. The university I come from did however teach linear algebra, ODEs and PDEs, etc as mandatory courses.

I don’t disagree that computer science intuition isn’t interesting, or that CS people can’t contribute. There are plenty of deep connections all over the place. You can conjecture all you want. My issue is with the tone.

I'm not sure where such negative emotions towards people throwing their intuition and expecting further discussing from experts comes from. Don't think anyone is suggesting that people at the "forefront" aren't capable of coming up with such ideas themselves, more like framing the familiar in other contexts to kick-off a discussion.

Except if they are framed as authoritative statement, rather than a genuine question or even wild conjecture. Then if a non expert reads it, believes it comes from someone expert, they can then take away something completely incorrect. Yes ask questions, but be honest.

I think there is plenty of pessimism in the OP. Essentially physicists today do not understand quantum theory better than the last generation of physicists did. I got my master in physics 20 years ago, and it was fairly obvious to me then that this would be the case.

Now compare that with AI/ML or large scale data processing over the last 20 years. I don’t think you should assume that the smartest people were those that didn’t see this coming and wanted to spend their life on interpretations of double slit experiments and string theory.

" Don’t use your intuition developed from grinding out web crap to try and reason about the forefront of human knowledge. " . This should be stickied on every HN thread

Honestly the funniest comment I have ever seen on HN.

> Quantisation is a nearly well understood process

The layman’s explanation I received for this, perhaps incorrectly, is that you fill in variables for factors that you don’t understand or can’t measure with whatever value makes the rest of the theory / equation work. Is that at all correct?

I hope that's a misunderstanding or miscommunication. It might be useful in some limited contexts, but it would point to gaps in the theory (at minimum).

There are 19 free parameters in the Standard Model. These include such values as the mass of various particles (electron, muon, tau, six quarks, Higgs), Higgs vacuum expectation value, the strength of several interactions, and the mixing angles and phases for certain interactions.

You can rearrange some of the parameters so that they're not free, and redefine each of these in terms of some other related parameter — your choices here are pretty arbitrary; these values being chosen as the 'free' ones does not represent some fundamental truth.

We do not have some underling deeper theory that indicates why these numbers are the way they are. Why is the electron mass ~511 kEv while the up quark is 2.2 mEv? Why not 1.9 mEv? Why not 2.3 mEv? The Standard Model doesn't generally explain it, nor does it even really intend to explain it, just to describe it.

One theory, which I find quite plausible, is that there are many universes, all of which have variations on these constants. And the reason our universe is the way it is, is because we are here to observe it - given that most other configurations of these constants wouldn’t support life (the strong anthropic principle).

It's one that comes up, but first consider that it's not fundamentally clear to the layman that these values are actually completely "free parameters".

Imagine, if you will, benchmarking some unknown CPU, and determining that the fused multiply-add operation takes, idk, 17 times as long to execute as an increment operation. We might postulate that there other CPUs out there where it takes a different amount of time — arbitrary amounts of time! Alternatively, we might gain knowledge of the underlying CPU architecture and understand that fused multiply-add is implemented with a certain set of transistors, and that it's fundamentally more complex, though there's room for some variability based on the specific implementation. In such a world this "free parameter" is set as it is for a very specific reason: a transistor arrangement.

We have limited visibility into what's actually happening "underneath" our laws of physics. Some of the values we see could be truly arbitrary. Some of them might actually be controlled by some other field and change over time (though we haven't seen evidence of that so it seems less likely). Some of them could be a deeper artifact of the way the universe works.

If you look at things like string theory, which do try to describe in more detail and dial down the free parameters to just one ("length of the fundamental string" more or less) we are left with something that's frustratingly nonspecific until you locate a more-specific solution within the broader string-theory solution space and call it "the laws of physics." That specific location might indeed seem quite arbitrary; the question might then become, what relation does this hundreds-of-dimensional solution space have with our concepts of physical reality? And can other areas of that landscape be probed in any way meaningful to our experience of physics?

In terms of the parameters of the standard model, in any other field setting parameters with theory rather than experimentation would be ridiculous. But somehow when it comes to quantum mechanics everyone rediscovers their reductionist hat and demands that every theory neatly explain all the details without anyone actually entering a laboratory.

I'm not saying I'm not a little miffed there isn't yet a nice, lower-level theory that predicts all of QM, but man is it frustrating when people flip flop to and from pure empiricism at the drop of a hat, based on a layman's understanding of a mature, developed field.

All correct.

Oh ... and if things are still a bit floppy, just fix the gauge and you are good.

No, that sounds more like a (very distorted) description of regularization and/or renormalization.

Regularization techniques take effective field theories like the Standard Model, which are known to be inaccurate at high enough energies, and isolate their low-energy behavior.

For example: classical electrodynamics, interpreted naively, says that the total energy stored in an electron's electric field is infinite, since the field strength blows up to infinity at the position of the electron itself. As this isn't actually true, we know there must be physics going on very close to the electron that our theory doesn't account for. But even if our theory isn't the Final Truth, it's still capable of making perfectly good predictions far away from the electron, and we can't just sit around waiting for quantum mechanics to be discovered.

So we make the structure of the electron a parameter of our theory: it can't tell you what the force between two electrons is, but if you posit that the electron's charge is distributed like so, it can tell you what the force between two electrons would be.

We then use empirical data to reabsorb our new degree of freedom: this is renormalization. Instead of trying to predict the force between two electrons, we measure it, and then work backwards to figure out what the electron's charge distribution would have to look like to produce that force. In this particular case: the electron behaves as if it were a sphere about 10^-15 meters across. This is of course not the actual structure of the electron, but it reproduces the same low-energy classical physics.

> We then use empirical data to reabsorb our new degree of freedom: this is renormalization

Notably, in a less rigorous field, this process would be called "doing science to determine physical properties of things", which most people consider an acceptable pastime for physicists. As it turns out we can be pretty confident that the "experimental evidence" is bunk and there's something going on the theory can't account for, but it's funny that so many of the Monday morning quantum physicists think all this math stuff is just confusing the issue and pure, blind empiricism is the way to go.

Don’t use your intuition developed from grinding out web crap to try and reason about the forefront of human knowledge.

Have you tried front end web frameworks recently? String theory has nothing on them.

C String > String

Now I want my new job title to be string interpolation theorist.

I wish mine were "sell out simpleton"

100%

My friends a pretty decent physicist at Oxford and the hardest part of his research? Makefiles.

Tell them to use qtcreator. They don’t even need to use the qt framework, the makefiles are just generated.

I wish qmake had won the makefiles generator war the same way I wish hg won over git

Eventually there will be so many JavaScript libraries and frameworks that they will collapse in upon themselves and create a black hole.

node_modules

https://www.reddit.com/r/ProgrammerHumor/comments/6s0wov/hea...