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Is particle physics dead, dying, or just hard?

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

#111

Post by drdeca »

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 parts that go against my tastes (I don’t like needing to resort to distributions instead of proper functions), but that’s probably just intellectual laziness on my part.

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

#112

Post by galaxyLogic »

Paracompact wrote: post #57
cozzyd wrote: post #38

Earlier quoted context omitted.

Even better, there are the "nightmare" scenarios where dark matter can only interact gravitationally with Standard Model particles.

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 don't think there is any mystery to what we call "consciousness". Our senses and brain have evolved so we can "sense" the external world, so we can live in it and react to it. So why couldn''t we also sense what is happening inside our brains?

Our brain needs to sense our "inner talk" so we can let it guide our decision-making and actions. If we couldn't remember sentences, we couldn't remember "facts" and would be much worse for that. And talking with our "inner voice" and hearing it, isn't that what most people would call consciousness?

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

#113

Post by JumpCrisscross »

Paracompact wrote: post #39
JumpCrisscross wrote: post #32

Earlier quoted context omitted.

> you have to accept there will eventually be (hopefully simple) coincidences between certain fundamental values, no? No. It’s almost certainly not a coïncidence that these charges are symmetric like that (in stable particles that like to hang out together).

Whence your confidence? As they say in math, "There aren't enough small numbers to meet the many demands made of them." If we assume the turtle stack ends, and it ends simply (i.e. with small numbers), some of those numbers may wind up looking alike. Even more so if you find anthropic arguments convincing, or if you consider sampling bias (which may be what you mean by, "in stable particles that like to hang out toge…

> if you find anthropic arguments convincing

Which makes every constant fair game. Currently, we don’t have a good process for explaining multiple universes beyond divine preference. Hence the notion that a random number settled on mirror whole sums.

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

#114

Post by andyferris »

tasty_freeze wrote: post #15

Here is one fact that seems, to me, pretty convincing that there is another layer underneath what we know. The charge of electrons is -1 and protons +1. It has been experimentally measured out to 12 digits or so to be the same magnitude, just opposite charge. However, there are no theories why this is -- they are simply measured and that is it. It beggars belief that these just happen to be exactly (as far as we can…

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 charge is a kind of "defect" or "kink" in the photonic field, while color charge (quarks) are defects in the strong-force field, etc.

When an electron-positron pair is formed from a vacuum, we get all sorts of interesting geometry which I struggle to grasp or picture clearly. I understand the fact that these are fermions with spin-1/2 can similarly be explained as localized defects in a field of particles with integer spin (possibly a feature of the exact same "defect" as the charge itself, in the photonic field, which is what defines an electron as an electron).

EDIT:

> However, there are no theories why this is -- they are simply measured and that is it.

My take is that there _are_ accepted hypotheses for this, but solving the equations (of e.g. the standard model, in full 3D space) to a precision suitable to compare to experimental data is currently entirely impractical (at least for some things like absolute masses - though I think there are predictions of ratios etc that work out between theory and measurement - sorry not a specialist in high-energy physics, had more exposure to low-energy quantum topological defects).

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

#115

Post by tariky »

To my uneducated eye it looks like they are stuck in limbo for 120 years. Nothing practical has been create based on those theories. It is just words and calculations spinning in circles.

I wish those people focus on practical real world physics. So we all can enjoy new innovations.

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

#116

Post by atakan_gurkan »

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.

I disagree, but maybe only because we are using different definitions. For example, we have neutrino oscillations, this requires neutrino mass, which is not part of the standard model of particle physics. In cosmology, there is "lithium problem" (amongst others), which cannot be explained by Lambda-CDM. We know our physical theories are incomplete not only because our mathematical frameworks (GR & QFT) are incompatible (similar to the incompatibility of Maxwell's equations and the Galilean transformations that form the basis of Newtonian mechanics), but also there are these unexplained phenomena, much like the blackbody radiation at the turn of previous century.

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

#117

Post by jiggawatts »

PaulHoule wrote: post #18
tasty_freeze wrote: post #15

Here is one fact that seems, to me, pretty convincing that there is another layer underneath what we know. The charge of electrons is -1 and protons +1. It has been experimentally measured out to 12 digits or so to be the same magnitude, just opposite charge. However, there are no theories why this is -- they are simply measured and that is it. It beggars belief that these just happen to be exactly (as far as we can…

If it wasn't the case then matter wouldn't be stable.

An interesting early theory of gravity was: "What if opposite charges attract slight more strongly than identical charges repel each other?"

If you tally up the forces, the difference is a residual attraction that can model gravity. It was rejected on various experimental and theoretical grounds, but it goes to show that if things don't cancel out exactly then the result can still leave a universe that would appear normal to us.

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

#118

Post by Sniffnoy »

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.

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 standard model (because there are problems unless the mass comes from the Higgs mechanism, but in the standard model neutrinos can't participate in the Higgs mechanism due to always being left-handed). But whenever we do experiments to attempt to verify one of the ways of fixing this problem -- are there separate right-handed neutrinos we didn't know about, or maybe instead the right-handed neutrinos were just antineutrinos all along? -- we turn up nothing.

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

#119

Post by tehjoker »

galaxyLogic wrote: post #112
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 don't think there is any mystery to what we call "consciousness". Our senses and brain have evolved so we can "sense" the external world, so we can live in it and react to it. So why couldn''t we also sense what is happening inside our brains? Our brain needs to sense our "inner talk" so we can let it guide our decision-making and actions. If we couldn't remember sentences, we couldn't remember "facts" and would be…

another one that thinks they solved the hard problem of consciousness by addressing the easy problem. how on earth does a feedback system cause matter to "wake up"? we are making lots of progress on the easy problem though

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

#120

Post by tehjoker »

threethirtytwo wrote: post #106
iterance wrote: post #103

Earlier quoted context omitted.

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 catc…

genetic technology and computing technology have been the biggest drivers for a while. i do think it is remarkable to video call another continent. communication technology is disruptive and revolutionary though it looks like chaos. ai is interesting too if it lives up to the hype even slightly.

catching a rocket is very impressive, but its just a lower cost method for earth orbit. it does unlock megaconstellations tho

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