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Is particle physics dead, dying, or just hard?

quantamagazine.org

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Re: Is particle physics dead, dying, or just hard?

#201

Post by squeefers »

sliken wrote: post #73
ggm wrote: post #46

I am sure others will say it better, but the cat-in-the-box experiment is a shockingly bad metaphor for the idea behind quantum states and observer effect. I will commit the first sin, by declaring without fear of contradiction the cat actually IS either alive or dead. it is not in a superposition of states. What is unknown is our knowledge of the state, and what collapses is that uncertainty. If you shift this to th…

Along similar lines, the double-slit experiment, seems simple. Two slits let light though and you get bands where they constructively or destructively interfere, just like waves. However I still find it crazy that when you slow down the laser and one photon at a time goes through either slit you still get the bands. Which begs the question, what exactly is it constructively or destructively interfering with? Still se…

> However I still find it crazy that when you slow down the laser and one photon at a time goes through either slit you still get the bands.

why does nobody mention the fact the photon doesnt keep going through the same hole? like why is it randomly moving through the air in this brownian way? the laser gun doesnt move, the slit doesnt move, so why do different photons end up going through different holes?

Re: Is particle physics dead, dying, or just hard?

#203

Post by squeefers »

bsder wrote: post #127
beezle wrote: post #72

Earlier quoted context omitted.

Please do not conflate the broad "theoretical physics" with the very specific "beyond the standard model" physics questions. There are many other areas of physics with countless unsolved problems/mysteries.

Sure, there are things like "Really, how do superconductors work?", but nobody (mostly) believes that understanding things like that requires "new physics". And, I think, most people would place that kind of stuff under "solid state physics" anyway.

oh i dont know, being able to predict the path of a particle seems pretty basic to me, and it cannot be done for any given particle.

Re: Is particle physics dead, dying, or just hard?

#204

Post by sigmoid10 »

brazzy wrote: post #176
sigmoid10 wrote: post #167

Earlier quoted context omitted.

This kind of slow, incremental improvement that costs tens of billions of dollars and takes decades gave us the microchips that ultimately enabled you to type this comment on your phone/computer. The return on that investment is obvious. But it is not just about making money: The entire field of radiation therapy for cancer exists and continues to improve because people figured out ways to control particle beams with…

> This kind of slow, incremental improvement that costs tens of billions of dollars and takes decades gave us the microchips that ultimately enabled you to type this comment on your phone/computer. No. These two cases are absurdly different, and you're even completely misunderstanding (or misrepresenting) the meaning of the "tens of billions of dollars" figure. Microchips were an incremental improvement where the ind…

>Microchips were an incremental improvement where the individual increments yielded utility far greater than the investment.

You should look up how modern EUV lithography was commercialised. This was essentially a big plasma physics puzzle. If ASML hadn't taken on a ridiculous gamble (financially on the same order of magnitude as a new collider, esp. for a single colpany) with the research, Moore's law would have died long ago and the entire tech industry would be affected. And there was zero proof that this was going to work beforehand.

Re: Is particle physics dead, dying, or just hard?

#205

Post by jhrmnn »

adrian_b wrote: post #191
klipt wrote: post #24

Earlier quoted context omitted.

Doesn't that imply our theories are "good enough" for all practical purposes? If they're impossible to empirically disprove?

The existing theories are extremely far from being good enough for practical purposes. There exists a huge number of fundamental quantities that should be calculated from the parameters of the "standard model", but we cannot compute them, we can only measure them experimentally. For instance, the masses and magnetic moments of the proton, of the neutron and of all other hadrons, the masses and magnetic moments of the…

This depends very much on what "practical purposes" are. For almost all conceivable technology, relativistic quantum mechanics for electrons and light, ie QED, is sufficient fundamental theory. This is unlike before quantum mechanics, when we basically didn't have fundamental laws for chemistry and solid-state physics.

Re: Is particle physics dead, dying, or just hard?

#206

Post by squeefers »

WantonQuantum wrote: post #126
albatross79 wrote: post #97

Why are we even trying to look deeper? To fit our mathematical curves better? Abstract spacetime, fields, virtual particles, wave function collapse, quantized energy, wave particle duality, etc. This is all BS. And I'm not disputing the theories or the experimental results. These concepts are unintelligible. They are self contradictory. They are not even abstractions, they are mutually exclusive paradigms forced toge…

I find quite a lot of it very satisfying. For example, the deep mathematical symmetries of gauge theory and how they relate to the observed forces of the universe is truly amazing. The excellent Arvin Ash has a very accessible video about it: https://www.youtube.com/watch?v=paQLJKtiAEE

maybe thats the problem. satisfaction isnt understanding. string theory is exciting maths, but fits nothing in reality. maybe scientists should go back to explaining reality instead of whatever this current paradigm is

Re: Is particle physics dead, dying, or just hard?

#207

Post by crispyambulance »

brazzy wrote: post #176
sigmoid10 wrote: post #167

Earlier quoted context omitted.

This kind of slow, incremental improvement that costs tens of billions of dollars and takes decades gave us the microchips that ultimately enabled you to type this comment on your phone/computer. The return on that investment is obvious. But it is not just about making money: The entire field of radiation therapy for cancer exists and continues to improve because people figured out ways to control particle beams with…

> This kind of slow, incremental improvement that costs tens of billions of dollars and takes decades gave us the microchips that ultimately enabled you to type this comment on your phone/computer. No. These two cases are absurdly different, and you're even completely misunderstanding (or misrepresenting) the meaning of the "tens of billions of dollars" figure. Microchips were an incremental improvement where the ind…

>> Let the physicists build the damn thing and future society will be better off for sure.

> Absolutely not.

And what do YOU mean, "absolutely not"? You have no more say in what happens than anyone else unless you're high level politician, who would still be beholden to their constituents anyway.

And yet big science, like particle accelerators, STILL gets funding. There's plenty to go around. Sure, every once in a while a political imperative will "pull the plug" on something deemed wasteful or too expensive and maybe sometimes that's right. But we STILL have particle physics, we STILL send out pure science space missions, there are STILL mathematicians and theorists who are paid for their whole careers to study subject matter that has no remotely practical applications.

Not everything must have a straight-line monetary ROI.

Re: Is particle physics dead, dying, or just hard?

#208

Post by TheOtherHobbes »

T-A wrote: post #135
Sniffnoy wrote: post #118

Earlier quoted context omitted.

I wouldn't say that we have no experimental data which contradicts them. Rather, we do have experimental data which contradicts them, but no experimental data that points us in the direction of a solution (and whenever we go looking for the latter, we fail). Consider e.g. neutrino masses. We have plenty of experimental data indicating that neutrinos oscillate and therefore have mass. This poses a problem for the stan…

> the standard model neutrinos can't participate in the Higgs mechanism due to always being left-handed This again? It's only true if you insist on sticking with the original form of Weinberg's "model of leptons" from 1967 [1], which was written when massless neutrinos were consistent with available experimental data. Adding quark-style (i.e. Dirac) neutrino mass terms to the Standard Model is a trivial exercise. If…

It's trivial to add a matrix to account for neutrino masses, but that doesn't explain their origin.

That is not a trivial problem at all. It certainly has not been solved, and it's possible experiments will say "Both the current ideas are wrong."

Re: Is particle physics dead, dying, or just hard?

#209

Post by squeefers »

drdeca wrote: post #111
albatross79 wrote: post #97

Why are we even trying to look deeper? To fit our mathematical curves better? Abstract spacetime, fields, virtual particles, wave function collapse, quantized energy, wave particle duality, etc. This is all BS. And I'm not disputing the theories or the experimental results. These concepts are unintelligible. They are self contradictory. They are not even abstractions, they are mutually exclusive paradigms forced toge…

The universe is not obligated to appeal to your aesthetic tastes in its innermost functioning. Maybe you aren’t going to be satisfied with the sort of complicated mathematics which appears to be correct (or, on the right track). If you have complaints about the aesthetics of how the universe works, take it up with God. Personally, I think there is a lot of beauty to be found in it. I’ll admit that there are a few par…

> The universe is not obligated to appeal to your aesthetic tastes in its innermost functioning.

This is truly a copout. When science faulters in explaining the world we get answers like this. His argument isnt with the universe, but with out own scientific theories. If you dont want your theories about the physical world to explain physical world, then be an engineer. Science explains the world, engineers use those theories. QM has large gaps and doesnt actually explain much, but I guess the universe doesnt care whether our theories are wildly off the mark or not.

Re: Is particle physics dead, dying, or just hard?

#210

Post by mikkupikku »

z3phyr wrote: post #142
mikkupikku wrote: post #58

Earlier quoted context omitted.

Newtonian physics is good enough for almost everything that humans do. It's not good for predicting the shit we see in telescopes, and apparently it's not good for GPS, although honestly I think without general relativity, GPS would still get made but there'd be a fudge factor that people just shrug about. For just about anything else, Newton has us covered.

Microchips? A lot of quantum physics is applied here from the top of my mind.

Quantum mechanics is relevant to humanity because we build things which are very small. General relativity is not, because we're more or less incapable of actually doing things on a scale where it matters.
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