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How Many Elementary Particles Are There, Really?

quantamagazine.org

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Re: How Many Elementary Particles Are There, Really?

#21

Post by antonvs »

TheOtherHobbes wrote: post #18
jerf wrote: post #6

Earlier quoted context omitted.

You don't have to wonder, because they are. They're manifestations of fields. I think it is a reasonable answer to tell people "if you're looking for the short list of simplest things, the number of types of fields there are is probably what you're looking for". That doesn't invalidate this question in general, though the number of different answers from people looking at the same thing suggests it may be underspecif…

In QFT every particle type has its own field.

Every particle type has its own field, but the OP article is counting a single particle type multiple times based on properties like spin and polarization. At one point the article reaches the number 118. That corresponds directly to 37 quantum fields once you take the "double counting" into account.

Re: How Many Elementary Particles Are There, Really?

#22

Post by antonvs »

Noaidi wrote: post #8
jerf wrote: post #6

Earlier quoted context omitted.

You don't have to wonder, because they are. They're manifestations of fields. I think it is a reasonable answer to tell people "if you're looking for the short list of simplest things, the number of types of fields there are is probably what you're looking for". That doesn't invalidate this question in general, though the number of different answers from people looking at the same thing suggests it may be underspecif…

> They're manifestations of fields. Or wave. Everything is a quantum wave. https://www.vlatkovedral.com/everything-in-the-universe-is-a...

A wave is a phenomenon that propagates through a field - i.e. the field is what allows the wave to exist.

(The philosophy of that admittedly gets messy, though, e.g. "are fields real objects?")

Re: How Many Elementary Particles Are There, Really?

#23

Post by jiug »

BobbyTables2 wrote: post #4

Not being a Physicist, I have to wonder if all these particles are somehow manifestations of a simpler thing. Might there have been a point in time (long ago) where the “wave photon” and the “particle photon” seemed like possibly different things?

Even if we use "wave photon" and "particle photon" alternatively, they are only convenient ways of talking about the behavior of the "photon field". The same way when we say "it is raining" we don't mean there is an "it" that "rains" we should try to avoid giving too much litteral meaning to these descriptions.

That said, I get it is difficult, especially because we are using everyday language to talk about very-much-not-everyday stuff. We all needental hooks to anchor new knowledge and most of our intuition comes from the classical (not-quantum) world around us.

As a physicist, I feel the art is in learning when to use what description, what Sean Carrol calls "poetic naturalism".

Re: How Many Elementary Particles Are There, Really?

#24

Post by antonvs »

BobbyTables2 wrote: post #4

Not being a Physicist, I have to wonder if all these particles are somehow manifestations of a simpler thing. Might there have been a point in time (long ago) where the “wave photon” and the “particle photon” seemed like possibly different things?

> I have to wonder if all these particles are somehow manifestations of a simpler thing.

Someone else already mentioned that yes, they're manifestations of quantum fields. This is well established - the dominant theory of particle physics, the Standard Model, is a theory of quantum fields.

In that context, a particle is simply the smallest excitation of a quantum field that can be detected. Fields can be "excited" (fluctuate) in many different ways, and the OP article is interpreting each one of those as a different type of particle. It's misleading.

Re: How Many Elementary Particles Are There, Really?

#25

Post by Noaidi »

GroksBarnacles wrote: post #12
Noaidi wrote: post #8

Earlier quoted context omitted.

> They're manifestations of fields. Or wave. Everything is a quantum wave. https://www.vlatkovedral.com/everything-in-the-universe-is-a...

A wave is already what we call a manifestation of a field, maybe I skimmed too quickly but I don't get the author's breakthrough point.

Yes, the field is the substrate.

"I insist upon the view that 'all is waves'."

    Letter to John Lighton Synge (9 November 1959), as quoted by Walter Moore in Schrödinger: Life and Thought (1989) ISBN 0521437679
It is not a breakthrough, it is just something we refuse to see, something that was known for a century.

"All is a wave" is the unifying principle. I am no mathematician, but the math needs to start with that fundamental principle.

The very notion of calling it "qunatum" physics is probably wrong since quantum is "a discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents."

And if everything is a wave there are no discrete quantities beyond our definition of what constitutes the end, or borders, of the wave.

Re: How Many Elementary Particles Are There, Really?

#26

Post by HarHarVeryFunny »

jerf wrote: post #6
BobbyTables2 wrote: post #4

Not being a Physicist, I have to wonder if all these particles are somehow manifestations of a simpler thing. Might there have been a point in time (long ago) where the “wave photon” and the “particle photon” seemed like possibly different things?

You don't have to wonder, because they are. They're manifestations of fields. I think it is a reasonable answer to tell people "if you're looking for the short list of simplest things, the number of types of fields there are is probably what you're looking for". That doesn't invalidate this question in general, though the number of different answers from people looking at the same thing suggests it may be underspecif…

But of course one can then question why are there exactly N different types of fields, with their specific types of interaction (at least in our universe)? Why should we suppose that this is the most fundamental description of reality, rather than being emergent from something else?

Re: How Many Elementary Particles Are There, Really?

#27

Post by andrewflnr »

Noaidi wrote: post #8
jerf wrote: post #6

Earlier quoted context omitted.

You don't have to wonder, because they are. They're manifestations of fields. I think it is a reasonable answer to tell people "if you're looking for the short list of simplest things, the number of types of fields there are is probably what you're looking for". That doesn't invalidate this question in general, though the number of different answers from people looking at the same thing suggests it may be underspecif…

> They're manifestations of fields. Or wave. Everything is a quantum wave. https://www.vlatkovedral.com/everything-in-the-universe-is-a...

> Now, when I told my editor at Allen Lane about my own interpretation, he immediately said “It’s Many Worlds on steroids!” There is a grain of truth in that, ...

Dude, this is an answer to an entirely different question. He's proposing an interpretation of QM, which is independent from "how many fundamental particles".

Re: How Many Elementary Particles Are There, Really?

#28

Post by [deleted] »

jerf wrote: post #6
BobbyTables2 wrote: post #4

Not being a Physicist, I have to wonder if all these particles are somehow manifestations of a simpler thing. Might there have been a point in time (long ago) where the “wave photon” and the “particle photon” seemed like possibly different things?

You don't have to wonder, because they are. They're manifestations of fields. I think it is a reasonable answer to tell people "if you're looking for the short list of simplest things, the number of types of fields there are is probably what you're looking for". That doesn't invalidate this question in general, though the number of different answers from people looking at the same thing suggests it may be underspecif…

[deleted]

Re: How Many Elementary Particles Are There, Really?

#29

Post by RobotToaster »

BobbyTables2 wrote: post #4

Not being a Physicist, I have to wonder if all these particles are somehow manifestations of a simpler thing. Might there have been a point in time (long ago) where the “wave photon” and the “particle photon” seemed like possibly different things?

Unified field theory https://en.wikipedia.org/wiki/Unified_field_theory
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