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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?

#101

Post by colechristensen »

klipt wrote: post #24
bananaflag wrote: post #7

It's basically the opposite situation from 150 years ago. Back then, we thought our theory was more or less complete while having experimental data which disproved it (Michelson-Morley experiment, Mercury perihelion, I am sure there are others). Right now, we know our theories are incomplete (since GR and QFT are incompatible) while having no experimental data which contradicts them.

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

Classical physics was indeed "good enough for all practical purposes" as well at the time... but those didn't include electronics, nuclear power, most all basic understanding of materials, chemistry, and just a tremendous amount of things.

The point being it's not at all clear what we might be missing without these impractical little mysteries that so far are very distant from every day life.

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

#103

Post by iterance »

threethirtytwo wrote: post #102

All of science is getting harder as the easiest discoveries are all pretty much behind us. LLMs were a breakthrough I didn't expect and it's likely the last one we'll see in our lifetime.

Specific fields may not advance for decades at a time, but we are hardly in a scientific drought. There have been dramatic advances in countless fields over the last 20 years alone and there is no good reason to expect such advances to abruptly cease. Frankly this is far too pessimistic.

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

#104

Post by nerdsniper »

refulgentis wrote: post #100
cozzyd wrote: post #81

Earlier quoted context omitted.

quantum mechanics (also very much not Newtonian) is much more important to our day-to-day lives.

Is it?

Flash memory (quantum tunneling), lasers (stimulated emission), transistors (band theory), MRI machines (nuclear spin), GPS (atomic transition), LED's (band gap), digital cameras (photoelectric effect), ...the list does, in fact, go on, and on, and on.

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

#105

Post by light_hue_1 »

Paracompact wrote: post #75
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.

I'm not assuming they have to be small integers—I'm saying that if the universe is built on discrete rather than continuous foundations, then small integers and coincidences at the bottom-turtle theory-of-everything become much less surprising. You're treating the space of possible charge values as if it's the reals, or at least some enormous range, but I consider that unlikely. Consider: in every known case where we…

Sparsity != symmetry.

It's simple to say "Ah well, it's sparse" that doesn't mean anything and doesn't explain anything.

Symmetries are equivalent to a conserved quantity. They exist because something else is invariant with respect to some transformation and vice versa. We didn't discover arbitrary constraints we found a conserved quantity & the implied symmetry.

"There are integers", "the numbers should be small" all of these are nothing like what works normally. They aren't symmetries. At most they're from some anthropic argument about collections of universes being more or less likely, which is its own rabbit hole that most people stay away from.

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

#106

Post by threethirtytwo »

iterance wrote: post #103
threethirtytwo wrote: post #102

All of science is getting harder as the easiest discoveries are all pretty much behind us. LLMs were a breakthrough I didn't expect and it's likely the last one we'll see in our lifetime.

Specific fields may not advance for decades at a time, but we are hardly in a scientific drought. There have been dramatic advances in countless fields over the last 20 years alone and there is no good reason to expect such advances to abruptly cease. Frankly this is far too pessimistic.

I don't understand what is wrong with pessimism. That's not a valid critique. If someone is pessimistic but his description of the world matches REALITY, then there's nothing wrong with his view point.

Either way this is also opinion based.

There hasn't been a revolutionary change in technology in the last 20 years. I don't consider smart phones to be revolutionary. I consider going to the moon revolutionary and catching a rocket sort of revolutionary.

Actually I take that back I predict mars as a possible break through along with LLMs, but we got lucky with musk.

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

#107

Post by drdeca »

epsilonsalts wrote: post #98
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…

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.

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

#108

Post by meindnoch »

im3w1l wrote: post #93
Paracompact wrote: post #57

Earlier quoted context omitted.

Personally—and this is where I expect to lose the materialists that I imagine predominate HN—I think we are already in a nightmare scenario with regard to another area: the science of consciousness. The following seem likely to me: (1) Consciousness exists, and is not an illusion that doesn't need explaining (a la Daniel Dennett), nor does it drop out of some magical part of physical theory we've somehow overlooked u…

I've thought about this possibility but come to reject it. If mind-matter interactions did not exist, then matter could not detect the presence of mind. And if the brain cannot detect the mind then we wouldn't be able to talk or write about the mind.

Or, the mind is in spectator mode?

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

#109

Post by jasonwatkinspdx »

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…

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 with both slots even though it looks like a singular "particle."

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

#110

Post by momoschili »

cozzyd wrote: post #81
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.

quantum mechanics (also very much not Newtonian) is much more important to our day-to-day lives.

this kind of distinction is quite stupid in general as plenty of things that we rely on for day-to-day activities such as our houses, desks, chairs, beds, shoes, clothes, etc are all based on Newtonian/classical mechanics. Basically everything that we use which existed pre-transistor strictly speaking only required classical physics.
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