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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?

#281

Post by adrian_b »

davrosthedalek wrote: post #233
adrian_b wrote: post #228

Earlier quoted context omitted.

The vast majority of useful things cannot be computed with QED from fundamental principles. You cannot compute even simple atomic energy spectra. The fundamental laws of chemistry have not been changed much by quantum physics, they just became better understood and less mysterious. Quantum mechanics has explained various cases of unusual chemical bonds that appeared to contradict the simpler rules that were believed…

What are you talking about? The spectra of hydrogen is very well understood and a text book example for students to calculate. We use spectra to test QED calculations to something like 14 digits.

The hydrogenoid atoms and ions, with a single electron, are the exception that proves the rule, because anything more complex cannot be computed accurately.

The spectrum of hydrogen (ignoring the fine structure) could be computed with the empirical rules of Rydberg before the existence of quantum physics. Quantum physics has just explained it in terms of simpler assumptions.

Quantum physics explains a great number of features of the atomic spectra, but it is unable to compute anything for complex atoms with an accuracy comparable with the experimental measurements.

The QED calculations with "14 digits" of precision are for things that are far simpler than atomic spectra, e.g. for the gyromagnetic ratio of the electron, and even for such things the computations are extremely difficult and error-prone.

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

#282

Post by bluGill »

hugh-avherald wrote: post #218
brazzy wrote: post #193

Earlier quoted context omitted.

Just as funny as armchair science enthusiasts not being able to fathom that research budgets are limited and it makes sense to redirect them into other, more promising fields when a particular avenue of research is both extremely expensive and has shown diminishing returns for decades.

Does targeting research towards 'more promising' fields actually produce greater economic returns?

There is no way to answer that - we have limited money/people/time. Whatever we fund - we will get whatever the returns are - but there is no way to know what we don't have because we didn't fund some other thing. Even if in a few years we fund that other thing - what we get out of those funds is influenced by the other things we already know and so whatever we get out of it also shows the results of the other research that we already have.

The only exception is if some research reveals nothing. Though this isn't a useful claim: "it doesn't work" still revealed something.

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

#283

Post by bluGill »

alphawhisky wrote: post #276
aleph_minus_one wrote: post #274

Earlier quoted context omitted.

> Let’s take a bunch of the smartest people alive, train them for decades, give them a month of Google money Unpopular opinion: Google makes an insane amount of money, so they can afford this salary. The CERN (or whatever your favourite research institute is), on the other hand, is no money-printing machine.

Every step towards understanding subatomic physics is a step towards cold fusion. The second we're able to understand and capture this energy, money literally doesn't exist. Infinite energy means infinite free energy, which would also abolish money from a fundamental market value perspective. I'll continually preach that we need to plan for this economically as a species because none of our current government or econ…

> Every step towards understanding subatomic physics is a step towards cold fusion.

Is it?

You are assuming cold fusion is possible. We don't know that. It might be one more step before we finally prove it is never possible.

You are also assuming that cold fusion is something this path of research will lead us to. However this might be a misstep that isn't helpful at all because it doesn't prove anything useful about the as yet unknown physical process that cold fusion needs.

We just don't know, and cannot know at this point.

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

#284

Post by parineum »

gosub100 wrote: post #244
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…

Why can't some of these trillion dollar companies invest back in the quantum tech that got them there, if it's so certain there will be benefits? Why not Apple and Nvidia fund the next particle collider, and give something back to society instead of letting tax payers fund it so billionaires can privatize the profits?

> Why not Apple and Nvidia fund the next particle collider, and give something back to society instead of letting tax payers fund it so billionaires can privatize the profits?

Where do you think that tax money comes from?

Apple and Nvidia are creating the economies that produce tax revenue at every step of the way.

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

#285

Post by AnimalMuppet »

franktankbank wrote: post #256
empath75 wrote: post #232

Earlier quoted context omitted.

> something like a winding number (which has to be an integer). Electric charge is a kind of "defect" or "kink" in the photonic field, while color charge (quarks) are defects in the strong-force field, etc. Quark's don't have integer charge

Redefine the down quark charge as the fundamental unit and you lose nothing.

Right, but then you have the questions of 1) why do leptons have (a multiple of) the same fundamental unit as quarks, and 2) why does that multiple equal the number of quarks in a baryon, so that protons have a charge of exactly the same magnitude as electrons?

I mean, I guess you could say that charge comes from (or is) the coupling of the quark/lepton field to the electromagnetic field, and therefore if it's something that's quantized on the electromagnetic side of that, then quarks and leptons would have the same scale. I'm not sure that's the real answer, much less that it's proven. (But it might be - it's a long time since my physics degree...)

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

#286

Post by toast0 »

ajam1507 wrote: post #243
toast0 wrote: post #237

Earlier quoted context omitted.

Spending tens of billions every thirty years is pretty sustainable actually. "Fundamental Research" may or may not pan out, but the things that happen along the way are often valuable... I don't think there's any practical applications related to generating Higgs Bosons, but it's interesting (at least for particle physicists) and there's a bunch of practical stuff you have to figure out to confirm them. That practica…

You could say the same thing about the world wars or porn. Any human pursuit taken to an extreme can produce knock-on effects, that isn't an argument in a vacuum to continue to fund any one area.

Spending tens of billions every 30 yesrs on world wars would be pretty awesome. Much better than what we currently spend.

Porn seems to be sustainably self funding; no need for government stimulus.

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

#287

Post by pixl97 »

brazzy wrote: post #253
hugh-avherald wrote: post #218

Earlier quoted context omitted.

Does targeting research towards 'more promising' fields actually produce greater economic returns?

Given that you can do a lot more research in different fields at the same time for the amount of money the next bigger particle accellerator would cost, the answer is very likely yes.

Ok, which field? How much money will be needed? What potential experiments are lined up in those fields that need money to go forward?

Particle physics has told us a lot about the base nature of our model and the affirmation of the standard model. The fruits of these labors still take decades to make their mark on our world.

And, we still are working on those other things at the same time too. It turns out with 8 billion people on the planet and modern technology we can get an absolute fuckload done at once.

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

#288

Post by AnimalMuppet »

auntienomen wrote: post #62
Paracompact wrote: post #21

Earlier quoted context omitted.

Technically, the charge of a proton can be derived from its constituent 2 up quarks and 1 down quark, which have charges 2/3 and -1/3 respectively. I'm not aware of any deeper reason why these should be simple fractional ratios of the charge of the electron, however, I'm not sure there needs to be one. If you believe the stack of turtles ends somewhere, you have to accept there will eventually be (hopefully simple) c…

There does appear to be a deeper reason, but it's really not well understood. Consistent quantum field theories involving chiral fermions (such as the Standard Model) are relatively rare: the charges have to satisfy a set of polynomial relationships with the inspiring name "gauge anomaly cancellation conditions". If these conditions aren't satisfied, the mathematical model will fail pretty spectacularly. It won't be…

So they have to cancel, or we don't have a universe? ("Have to" not because we need electrical neutrality for large-scale matter - though we do need that - but because you can't build a quantum field that doesn't explode in various ways without it.)

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

#290

Post by pixl97 »

brazzy wrote: post #194
bayindirh wrote: post #183

Earlier quoted context omitted.

> Absolutely not. I'd not be so sure about that. Doing this research will probably allow us to answer "it works but we don't know exactly why" cases in things we use everyday (i.e. li-ion batteries). Plus, while the machines are getting bigger, the understood tech is getting smaller as the laws of physics allows. If we are going to insist on "Absolutely not" path, we should start with proof-of-work crypto farms and A…

That "probably" is really more of a "maybe" given the experience with the current big accelerators, and really needs to be weighed against the extreme costs - and other, more promising avenues of research. > If we are going to insist on "Absolutely not" path, we should start with proof-of-work crypto farms and AI datacenters which consume county or state equivalents of electricity and water resources for low quality…

>and other, more promising avenues of research.

Which are? Just asking for the purposes of this discussion.

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