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What Is a Particle? (2020)

quantamagazine.org

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Re: What Is a Particle? (2020)

#41

Post by kayo_20211030 »

fragmede wrote: post #35
kayo_20211030 wrote: post #3

A particle is a thing you can "look" at, and say "that's a particle". It is whatever one says it is. They're not exactly discovered, they're invented. Fundamental in this context is not so much a word as it is an analogy. And, don't get me wrong, that doesn't mean particles don't exist. They do. But, a particle is whatever we say it is.

discovery vs invention is a question in mathematics as well. trying to say they're invented isn't clever, it's just a trick of language, like how gravity is merely a theory. particles are theorized to exist via theoretical physics and math, and then tested for experimentally. or as the saying goes, all models are wrong, some are useful.

I can't find the reference at the moment. But, I think it was about the "creation" of the quark. (I'll find it eventually). Either way, a search for reality, no matter how far we've progressed thus far, is either a search for a platonic reality, or an experimental reality. The former is "discovery" and the latter is "invention". It really doesn't matter. I don't think, right now, we're quite smart enough to pry into the mind of the universe, so we'll keep "inventing" things until we actually approach "discovery" asymptotically. Maybe we'll get there, but we've never been closer :-)

Re: What Is a Particle? (2020)

#42

Post by akira2501 »

interroboink wrote: post #40
akira2501 wrote: post #37

Earlier quoted context omitted.

We understand matter perfectly well. Look at the size and scope of the engineering marvels that have been constructed on the surface of this planet and in our low orbit. It's astonishing. What we don't understand is the fundamental structure of that matter or of our Universe. I personally feel that the people ostensibly "in charge" of this effort are a little chagrined at their decades of inability to produce not onl…

I think there's a useful distinction to be made between "we understand it" and "we can make use of it." Certainly the latter is true, as you describe in your examples. I don't know that it implies the former, though. I mean heck, even something as mundane as concrete is still the subject of active research as to the chemical reactions and complexities involved. I guess it's more a spectrum of understanding than a yes…

I think the distinction is more "we understand it" and "we can explain it." Understanding doesn't generally imply totality of comprehension.

Going the other way, you most likely cannot explain why your body or your brain works, yet, here we are, using and understanding them just fine.

Which leads to what I was trying to get at. Perhaps our tentative understandings and our means of receiving them are what gets in the way of deeper comprehension.

Re: What Is a Particle? (2020)

#43

Post by bbor »

jophj wrote: post #31
ww520 wrote: post #24

That's why calling Higgs Boson the God particle is not quite right. It's the Higgs field that gives mass to the other particles, not the Boson. A Higgs Boson is just an excitation of the Higgs field; it doesn't give mass to other particles. In fact it's the Higgs field modifying the other fields causing their excitations (particles) to slow down when passing each other, thus gaining masses.

it was in fact called the "Goddamn Particle" originally, referring to how difficult it was to detect it. The name was changed later to "God Particle" for publishing reasons. https://en.m.wiktionary.org/wiki/God_particle

The line between whimsy and intellectual negligence seems blurry, in this case… how many people have been tricked by bad-faith gurus using this?

Thanks for sharing, TIL and it’s fascinating.

Re: What Is a Particle? (2020)

#44

Post by bbor »

AlbertCory wrote: post #2

I'm reading "The Big Picture" (Sean Carroll) right now. I'd love to have a real physicist explain this, but: When we think of what a particle IS, we often think as though it were dirt, or a billiard ball, or something. As though there were some other substance of which it's made. At least I do. But the definition is as low as you can go. It's hard to wrap your head around that. Unless you're trained to do so, I guess…

I’m not a physicist, but as an arrogant philosopher of science: isn’t it just field excitation? Like, every particle looks like a circle bouncing around a 2D piece of paper, but if you look reeaaaaally closely it’s just a localized 3D spike of energy in a usually 2D field of energy? So it’s made of the field/paper itself.

I must be under-thinking this, but that’s what’s worked pretty convincingly for me.

Re: What Is a Particle? (2020)

#45

Post by lisper »

AlbertCory wrote: post #2

I'm reading "The Big Picture" (Sean Carroll) right now. I'd love to have a real physicist explain this, but: When we think of what a particle IS, we often think as though it were dirt, or a billiard ball, or something. As though there were some other substance of which it's made. At least I do. But the definition is as low as you can go. It's hard to wrap your head around that. Unless you're trained to do so, I guess…

Richard Feynman gave what I consider to be the best possible answer to questions like this:

https://www.youtube.com/watch?v=Q1lL-hXO27Q

Re: What Is a Particle? (2020)

#46

Post by auntienomen »

criddell wrote: post #26
danbruc wrote: post #22

Earlier quoted context omitted.

I mean I can not speak for you, but I do not think that the problem necessarily is that people think of them as made from some stuff, I think what causes the most trouble is the desire to visualize particles. The trouble is that an electron is an electron and it is nothing like anything you have ever seen in your macroscopic classical world. It shares some aspects with billiard balls and some with water waves but it…

> And electrons being electrons also means that they are not excitations in quantum fields You’re going against the dominant interpretation of QFT here, aren’t you?

Yep. Also, ignoring all the ways in which an electron isn't an electron. Electrons can be created and destroyed, and they are both indistinguishable and exchangeable. We can't assign identity to them, thanks to their Fermi statistics. They're just methods of explaining clicks in a detector.

I worked in particle physics for years and never once saw an electron. :-)

Re: What Is a Particle? (2020)

#47

Post by prng2021 »

kayo_20211030 wrote: post #27
prng2021 wrote: post #10

Earlier quoted context omitted.

We're not asking questions about human constructs like what is moral or what is the ideal form of government. We're trying to understand what the most fundamental building block of reality is, which is something objective. Something independent of whether of not people ever existed. So no, countless people around the world aren't wasting their lives researching particles when the answer is simply, it's whatever we sa…

Did you take the time to read the original piece? Even the smart people can't agree. What gives you the faith that a "particle" is not a human construct? What on earth does "fundamental" even mean except being the bottom turtle we can see on the particular mountain of turtles at which we're looking. "Countless"(?) people around the world are not researching particles. They're doing particle physics as they understand…

When you say particles are whatever we say they are, I assume you believe particles are subjective. I'm saying particles are objective, like a "wavelength" as opposed to subjective, like "morals".

If you are saying even objective things are whatever we say they are, then this is a useless discussion. Obviously every word is defined with other words and all words are human creations. So yea in that sense, literally everything we know of is whatever we say it is. That's a pointless statement to make in response to this article or really ever.

Re: What Is a Particle? (2020)

#48

Post by xanderlewis »

elashri wrote: post #9
AlbertCory wrote: post #2

I'm reading "The Big Picture" (Sean Carroll) right now. I'd love to have a real physicist explain this, but: When we think of what a particle IS, we often think as though it were dirt, or a billiard ball, or something. As though there were some other substance of which it's made. At least I do. But the definition is as low as you can go. It's hard to wrap your head around that. Unless you're trained to do so, I guess…

> we often think as though it were dirt, or a billiard ball, or something The problem lies that it is hard to imagine something that does have zero dimensions. You can get the example of ant walking into 2D and it is unaware of third dimension to explain we are have something similar for space-time 4D (although not the same picture exactly as time is different from spatial dimensions). But we don't have an idea how t…

> The problem lies that it is hard to imagine something that does have zero dimensions.

Do you really think so? It’s not hard to picture the real number line, with the point zero (or any other single point) distinguished. Sure — if you draw it in the standard schematic way you have to give it some area, but it still seems quite intuitive that it’s ‘zero-dimensional’. Especially if you play around with converging sequences and open sets and stuff; you quickly develop intuition for what it means to be a point rather than something higher dimensional.

Re: What Is a Particle? (2020)

#49

Post by tambourine_man »

akira2501 wrote: post #42
interroboink wrote: post #40

Earlier quoted context omitted.

I think there's a useful distinction to be made between "we understand it" and "we can make use of it." Certainly the latter is true, as you describe in your examples. I don't know that it implies the former, though. I mean heck, even something as mundane as concrete is still the subject of active research as to the chemical reactions and complexities involved. I guess it's more a spectrum of understanding than a yes…

I think the distinction is more "we understand it" and "we can explain it." Understanding doesn't generally imply totality of comprehension. Going the other way, you most likely cannot explain why your body or your brain works, yet, here we are, using and understanding them just fine. Which leads to what I was trying to get at. Perhaps our tentative understandings and our means of receiving them are what gets in the…

> yet, here we are, using and understanding them just fine.

I think we’re failing miserably precisely because we don’t.

Re: What Is a Particle? (2020)

#50

Post by aaa_aaa »

lisper wrote: post #45
AlbertCory wrote: post #2

I'm reading "The Big Picture" (Sean Carroll) right now. I'd love to have a real physicist explain this, but: When we think of what a particle IS, we often think as though it were dirt, or a billiard ball, or something. As though there were some other substance of which it's made. At least I do. But the definition is as low as you can go. It's hard to wrap your head around that. Unless you're trained to do so, I guess…

Richard Feynman gave what I consider to be the best possible answer to questions like this: https://www.youtube.com/watch?v=Q1lL-hXO27Q

At first I was impressed with that video. Then I felt he does not have an answer and unnecessarily gets edgy with it, because question is valid.
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