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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?

#171

Post by kakacik »

mattlangston wrote: post #71

Experimental particle physicist here. It's just hard. I measured the electron's vector coupling to the Z boson at SLAC in the late 1990s, and the answer from that measurement is: we don't know yet - and that's the point. Thirty years later, the discrepancy between my experiment and LEP's hasn't been resolved. It might be nothing. It might be the first whisper of dark matter or a new force. And the only way to find ou…

Its a clickbait article name (from otherwise good place), of course its not dead... we are now getting understanding of all things we don't know yet, discrepancies like yours, unified theory and so on.

Everybody knows we are not there yet and how the final knowledge set will look like, if its even possible to cover it (ie are quarks the base layer or we can go deeper, much deeper all the way to planck scales? dynamics of singularities etc)

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

#172

Post by adrianN »

jhanschoo wrote: post #77
Legend2440 wrote: post #45

Earlier quoted context omitted.

Typically whenever you look closely at an object with complex behavior, there is a system inside made of smaller, simpler objects interacting to produce the complexity. You'd expect that at the bottom, the smallest objects would be extremely simple and would follow some single physical law. But the smallest objects we know of still have pretty complex behavior! So there's probably another layer underneath that we don…

I agree, and I think that your claim is compatible with the comment that you are responding to. Indeed, perhaps it's turtles all the way down and there is systematic complexity upon systematic complexity governing our universe that humanity has been just too limited to experience. For a historical analogy, classical physics was and is sufficient for most practical purposes, and we didn't need relativity or quantum me…

The experiments that lead to the invention of quantum theory are relatively simple and involve objects you can touch with your bare hands without damaging them. Some are done in high school, eg the photoelectric effect.

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

#173

Post by thegabriele »

jaybrendansmith wrote: post #89
tasty_freeze wrote: post #64

Earlier quoted context omitted.

Why do you assume the two have to be small integers? There is nothing currently in physics which would disallow the electron to be -1 and the proton to be +1234567891011213141516171819. The fact they are both of magnitude 1 is a huge coincidence.

Perhaps only visible matter is made up of particles with these exactly matching charges? If they did not match, they would not stay in equilibrium, and would not be so easily found.

I like this survivorship bias, "evolution" works in everything why not in the shaping of the "costants" of the universe as we know it?

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

#174

Post by raverbashing »

sashank_1509 wrote: post #158
mattlangston wrote: post #71

Experimental particle physicist here. It's just hard. I measured the electron's vector coupling to the Z boson at SLAC in the late 1990s, and the answer from that measurement is: we don't know yet - and that's the point. Thirty years later, the discrepancy between my experiment and LEP's hasn't been resolved. It might be nothing. It might be the first whisper of dark matter or a new force. And the only way to find ou…

What would the cost of the “next machine” be? Is it going to be tens of billions or can we make progress with lesser money. If it is going to be tens of billions, then maybe we need to invest in engineering to reduce this cost, because it’s not sustainable to suspend thirty years, tens of billions for every incremental improvement.

The next machine is not necessarily a longer LHC

There are talks of a Muon collider, also there's a spallation source being built in Sweden(?) and also of an electron 'Higgs factory' (and while the LHC was built for the Higgs boson it is not a great source for it - it is built as a generic tool that could produce and see the Higgs)

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

#175

Post by el_nahual »

jasonwatkinspdx wrote: post #109
sliken wrote: post #73

Earlier quoted context omitted.

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…

The most simple answer here is the "fields are real, particles are excitation patterns of fields." And that's generally the practical way most physicists think of it today as I understand it. If I make the equivalent of a double slit experiment in a swimming pool, then generate a vortex that propagates towards my plywood slits or whatever, it's not really surprising that the extended volume of the vortex interacts wi…

And yet if you place a detector at the slits to know which slit the single photon goes through, you get no interference pattern at the end.

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

#176

Post by brazzy »

sigmoid10 wrote: post #167
sashank_1509 wrote: post #158

Earlier quoted context omitted.

What would the cost of the “next machine” be? Is it going to be tens of billions or can we make progress with lesser money. If it is going to be tens of billions, then maybe we need to invest in engineering to reduce this cost, because it’s not sustainable to suspend thirty years, tens of billions for every incremental improvement.

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 individual increments yielded utility far greater than the investment.

For particle physics, the problem is that the costs have exploded with the size of facilities to reach higher energies (the "tens of billions of dollars" is for one of them) but the results in scientific knowledge (let alone technological advances) have NOT. The early accelerators cost millions or tens of millions and revolutionized our undestanding of the universe. The latest ones cost billions and have confirmed a few things we already thought to be true.

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

Absolutely not.

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

#177

Post by GordonS »

krzat wrote: post #164
libraryofbabel wrote: post #40

Earlier quoted context omitted.

There’s a name for that: the Anthropic principle. And it is deeply unsatisfying as an explanation. And does it even apply here? If the charge on the electron differed from the charge on the proton at just the 12th decimal place, would that actually prevent complex life from forming. Citation needed for that one. I agree with OP. The unexplained symmetry points to a deeper level.

I find the anthropic principle fascinating. I was born to this world at a certain point in time. I look around, and I see environment compatible with me: air, water, food, gravity, time, space. How deep does this go? Why I am not an ant or bacteria?

Presumably your parents weren't ants?

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

#178

Post by bananaflag »

drdeca wrote: post #107
epsilonsalts wrote: post #98

Earlier quoted context omitted.

Yeah that's the outcome theorized by Gödel. Incompleteness is inherent to our understanding as the universe is too vast and endless for us to ever capture a holistic model of all the variables. Gödel says something specific about human axiomatic systems, akin to a special relativity, but it generalizes to physical reality too. A written system is made physical writing it out, and never complete. Demonstrates that our…

Gödel’s incompleteness says almost nothing about this. I wish people wouldn’t try to apply it in ways that it very clearly is not applicable to. An environment living in Conway’s Game of Life could be quite capable of hypothesizing that it is implemented in Conway’s Game of Life.

Indeed, as I think I commented before here, this kind of self-reference is exactly what makes Gödel's proof work.

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

#179

Post by UncleSlacky »

RupertSalt wrote: post #151
andyferris wrote: post #114

Earlier quoted context omitted.

The hint from quantum field theory (and things like lattice gauge theory) is that charge emerges from interesting topological states/defects of the underlying field (by "interesting topological shapes" I mean - imagine a vortex in the shape of a ring/doughnut). It's kind of a topological property of a state of the photonic field, if you will - something like a winding number (which has to be an integer). Electric cha…

> interesting topological states/defects of the underlying field eddies in the space-time continuum?

Is he?

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

#180

Post by paganel »

f30e3dfed1c9 wrote: post #79
smnplk wrote: post #44

Earlier quoted context omitted.

There are layers science can not access.

Well OK then! Let's tell all the physicists they can close up shop now. They might not have realized it, but they're done. All their little "theories" and "experiments" and what not have taken them as far as they can go.

> Let's tell all the physicists they can close up shop now.

Yes, that's part of the plan. I mean, not to all the physicists, just to those whose work doesn't bring in results anymore, and it hasn't for 30 to 40 years now. At some point they (said physicists) have to stop their work and ask themselves what it is that they're doing, because judging by their results it doesn't seem like they're doing much, while consuming a lot of resources (which could have been better spent elsewhere).

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