(December 31, 2022 at 11:17 am)LinuxGal Wrote:

(December 31, 2022 at 11:08 am)polymath257 Wrote: The essence of science is the scientific method: to test all ideas via observation, to only consider ideas that are testable (usually falsifiable) and to agree to modify or eliminate those ideas that are shown wrong via observation.

Nothing in this method *requires* 'matter' or even 'physical' aspects to be fundamental.

A particle is fundamental when it is determined to have no constituents.

An electron, for example, is fundamental, while a proton, made of (fundamental) quarks and gluons, is composite, even though energetically a proton has no decay channel (under the Standard Model at least, if not under assorted proposed extensions to the SM).

Fundamental implies that the chain of inquiry has terminated.  The masses of fundamental particles (if they have masses) are simply brute empirical facts.  This makes for an unwieldy theory, but it's the best we have.

Which, again, does not address the question of what it means to be 'matter' or 'material'.

A photon is fundamental, but is usually NOT considered to be matter (it isn't made of atoms, for example), while it *is* physical. Muons are usually regarded as fundamental as well (although they decay into electrons and neutrinos), but are not considered by most to be 'matter' even though they are fermions.

Whether electrons and quarks are truly fundamental is still in question. There are theories that have quarks as composite particles. To say that the chain of inquiry has terminated says that science has nothing further to say, which is almost never the case.

For example, are electrons and muons simply resonance states of the same particle? Is there a symmetry between fermions and bosons?

Ultimately, whether photons and other bosons are labeled as 'matter' or not is pretty irrelevant. Science is based on using observation to test our ideas. There is no required assumption that all explanations are in terms of matter or even physical things. But there *is* an expectation that all ideas have testable results.

(December 31, 2022 at 12:23 pm)Jehanne Wrote:

(December 31, 2022 at 12:01 pm)Angrboda Wrote: Matter and mass are not equivalent terms.

Energy would be in Joules, mass would be in kilograms and '"c squared' would be meters squared divided by seconds squared.

And in relativistic units, they would be the same.

But that isn't relevant to the comment you are replying to, which has to do with the distinction between 'matter' and 'mass'. Mass has a very definite meaning in physics, related to the rest energy of a particle. Matter has no such basic meaning, being more of a term used by chemists and concerned at a different level of organization. Some physicists label a particle 'matter' if it is a first generation fermion. So up and down quarks and electrons qualify, but photons, strange quarks, gluons, and Higg's bosons do not.

Angrboda is correct here.

(December 31, 2022 at 3:54 pm)Jehanne Wrote:

(December 31, 2022 at 3:54 pm)Angrboda Wrote: Are you including me in that group?

Yes.

Considering that Angrboda is correct in this case, that seems rather, well, strange.

(December 31, 2022 at 7:11 pm)polymath257 Wrote:

(December 31, 2022 at 11:17 am)LinuxGal Wrote: A particle is fundamental when it is determined to have no constituents.

An electron, for example, is fundamental, while a proton, made of (fundamental) quarks and gluons, is composite, even though energetically a proton has no decay channel (under the Standard Model at least, if not under assorted proposed extensions to the SM).

Fundamental implies that the chain of inquiry has terminated.  The masses of fundamental particles (if they have masses) are simply brute empirical facts.  This makes for an unwieldy theory, but it's the best we have.

Which, again, does not address the question of what it means to be 'matter' or 'material'.

A photon is fundamental, but is usually NOT considered to be matter (it isn't made of atoms, for example), while it *is* physical. Muons are usually regarded as fundamental as well (although they decay into electrons and neutrinos), but are not considered by most to be 'matter' even though they are fermions.

Whether electrons and quarks are truly fundamental is still in question. There are theories that have quarks as composite particles. To say that the chain of inquiry has terminated says that science has nothing further to say, which is almost never the case.

For example, are electrons and muons simply resonance states of the same particle? Is there a symmetry between fermions and bosons?

Ultimately, whether photons and other bosons are labeled as 'matter' or not is pretty irrelevant. Science is based on using observation to test our ideas. There is no required assumption that all explanations are in terms of matter or even physical things. But there *is* an expectation that all ideas have testable results.

Whether photons are matter or not sounds like the question whether Pluto is a planet or not.  Photons curve space and they can cause a solar sail to accelerate through recoil, which is material enough for government work. Physics is about cataloguing what is.  Photons are.  They are physical, just as Higgs particles and gluons are. But there is an expectation they are essentially different from matter because when a positron and electron annihilate each other all you have left is photons. Then again, we know in high energy collisions this works the other way around, and photons can be intermediate states between colliding protons and any number of other particles, maybe like this:

(December 31, 2022 at 7:27 pm)LinuxGal Wrote:

(December 31, 2022 at 7:11 pm)polymath257 Wrote: Which, again, does not address the question of what it means to be 'matter' or 'material'.

A photon is fundamental, but is usually NOT considered to be matter (it isn't made of atoms, for example), while it *is* physical. Muons are usually regarded as fundamental as well (although they decay into electrons and neutrinos), but are not considered by most to be 'matter' even though they are fermions.

Whether electrons and quarks are truly fundamental is still in question. There are theories that have quarks as composite particles. To say that the chain of inquiry has terminated says that science has nothing further to say, which is almost never the case.

For example, are electrons and muons simply resonance states of the same particle? Is there a symmetry between fermions and bosons?

Ultimately, whether photons and other bosons are labeled as 'matter' or not is pretty irrelevant. Science is based on using observation to test our ideas. There is no required assumption that all explanations are in terms of matter or even physical things. But there *is* an expectation that all ideas have testable results.

Whether photons are matter or not sounds like the question whether Pluto is a planet or not.  Photons curve space and they can cause a solar sail to accelerate through recoil, which is material enough for government work. Physics is about cataloguing what is.  Photons are.  They are physical, just as Higgs particles and gluons are. But there is an expectation they are essentially different from matter because when a positron and electron annihilate each other all you have left is photons. Then again, we know in high energy collisions this works the other way around, and photons can be intermediate states between colliding protons and any number of other particles, maybe like this:

Which, again, is to my point. The label (material, physical, etc) is irrelevant. What is important is whether the ideas are testable via observation.

(December 31, 2022 at 7:23 pm)polymath257 Wrote:

(December 31, 2022 at 3:54 pm)Jehanne Wrote: Yes.

Considering that Angrboda is correct in this case, that seems rather, well, strange.

Why? The '=' sign implies that the dimensional analysis is correct, namely, 1 joule = kg * (m / s) ^ 2 in SI units. That's all I stated in my reply.

(December 31, 2022 at 7:30 pm)polymath257 Wrote:

(December 31, 2022 at 7:27 pm)LinuxGal Wrote: Whether photons are matter or not sounds like the question whether Pluto is a planet or not.  Photons curve space and they can cause a solar sail to accelerate through recoil, which is material enough for government work. Physics is about cataloguing what is.  Photons are.  They are physical, just as Higgs particles and gluons are. But there is an expectation they are essentially different from matter because when a positron and electron annihilate each other all you have left is photons. Then again, we know in high energy collisions this works the other way around, and photons can be intermediate states between colliding protons and any number of other particles, maybe like this:

Which, again, is to my point. The label (material, physical, etc) is irrelevant. What is important is whether the ideas are testable via observation.

You're pounding on open doors. Non-material explanations are not testable. Of the 20 million or so scientific papers published in the last century, cite a single one that addresses "non-material" forces.

(December 31, 2022 at 12:01 pm)Angrboda Wrote: Matter and mass are not equivalent terms.

Quote:In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume.[1] All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, "matter" generally includes atoms and anything made up of them, and any particles (or combination of particles) that act as if they have both rest mass and volume.

https://en.m.wikipedia.org/wiki/Matter

(December 31, 2022 at 7:27 pm)LinuxGal Wrote:

(December 31, 2022 at 7:11 pm)polymath257 Wrote: Which, again, does not address the question of what it means to be 'matter' or 'material'.

A photon is fundamental, but is usually NOT considered to be matter (it isn't made of atoms, for example), while it *is* physical. Muons are usually regarded as fundamental as well (although they decay into electrons and neutrinos), but are not considered by most to be 'matter' even though they are fermions.

Whether electrons and quarks are truly fundamental is still in question. There are theories that have quarks as composite particles. To say that the chain of inquiry has terminated says that science has nothing further to say, which is almost never the case.

For example, are electrons and muons simply resonance states of the same particle? Is there a symmetry between fermions and bosons?

Ultimately, whether photons and other bosons are labeled as 'matter' or not is pretty irrelevant. Science is based on using observation to test our ideas. There is no required assumption that all explanations are in terms of matter or even physical things. But there *is* an expectation that all ideas have testable results.

Whether photons are matter or not sounds like the question whether Pluto is a planet or not.  Photons curve space and they can cause a solar sail to accelerate through recoil, which is material enough for government work. Physics is about cataloguing what is.  Photons are.  They are physical, just as Higgs particles and gluons are. But there is an expectation they are essentially different from matter because when a positron and electron annihilate each other all you have left is photons. Then again, we know in high energy collisions this works the other way around, and photons can be intermediate states between colliding protons and any number of other particles, maybe like this:

I never claimed that photons were "matter"; you are putting words into my mouth/writing.

(December 31, 2022 at 8:25 pm)Jehanne Wrote:

(December 31, 2022 at 7:27 pm)LinuxGal Wrote:

I never claimed that photons were "matter"; you are putting words into my mouth/writing.

Everything on that fine man's diagram is matter, including the squiggly lines marked with lower-case Greek gamma letters, asterisks notwithstanding.