[allo4]

I don't have a scientific background so this is probably a silly question to someone that does...

If in the reaction of a radioactive material decaying it releases photons is it ridiculous to suggest that electrons protons ect are just made of photons.
when you heat something it releases light too, and like when you heat water the atoms gain energy and move around the extreme ones moving fast enough and far enough away from each other to escape the liquid state the 'photons in the electron' escape when heated too.
I'm sure I heard that in billions of billions of years all the electrons ect will decay but what else would be released from them and so what else could they be made of?

This post has been edited by allo4: 16 October 2011 - 09:44 PM

[swansont]

It's not ridiculous to ask, but the evidence says no. In these decays all of those particles are accounted for, and there are other ways of getting photons. There are several conservation laws that have to be followed, and the model that has photons as distinct particles works.

[IM Egdall]

And here is another thing that comes to mind. Photons have no mass. Matter particles (electrons, neutrinos, quarks) do have mass. So how can particles which have no mass make up particles that do have mass? So it appears from this that photons cannot build up to make matter particles.

This post has been edited by IM Egdall: 16 October 2011 - 11:09 PM

[timo]

IM Egdall, on 16 October 2011 - 11:09 PM, said:

And here is another thing that comes to mind. Photons have no mass. Matter particles (electrons, neutrinos, quarks) do have mass. So how can particles which have no mass make up particles that do have mass? So it appears from this that photons cannot build up to make matter particles.

I think it has already been said that the argument with the mass is not entirely convincing. But it is funny that all what you said is completely correct except for the word "mass". Had you said "electrical charge" or "half-integer spin" then your statement would have been a great argument.

[IM Egdall]

timo, on 17 October 2011 - 06:40 AM, said:

I think it has already been said that the argument with the mass is not entirely convincing. But it is funny that all what you said is completely correct except for the word "mass". Had you said "electrical charge" or "half-integer spin" then your statement would have been a great argument.

Ya, good point. It occurred to me as I read this that two colliding photons can (and do) produce matter particles if their energy is high enough. So, as you point out, the charge and half-integer spin are much better arguments.

[imatfaal]

IM Egdall, on 17 October 2011 - 08:36 PM, said:

Ya, good point. It occurred to me as I read this that two colliding photons can (and do) produce matter particles if their energy is high enough. So, as you point out, the charge and half-integer spin are much better arguments.

Tom Swanson mentioned this in another thread as well - the last time I looked for info on photon/photon interaction it was really hard to find anything I could rely upon (the conditions were so extreme and it was debatable (not by me but by real physicists) if any photon/photon was actually happening amongst the noise) . Have there been developments? and do you have any links ? thanks

[Genius13]

well we r just photons
in the big bang only energy came out ( photons ) witch , using the formula E=mc2 , turned into pairs of matter and antimatter
those two anihalated with each other , but a breaking of simetry ( 1 bilion antimatter to 1bilion and 1 matter ) caused us to be here today

[IM Egdall]

imatfaal, on 18 October 2011 - 01:02 PM, said:

Tom Swanson mentioned this in another thread as well - the last time I looked for info on photon/photon interaction it was really hard to find anything I could rely upon (the conditions were so extreme and it was debatable (not by me but by real physicists) if any photon/photon was actually happening amongst the noise) . Have there been developments? and do you have any links ? thanks

http://en.wikipedia....Pair_production

http://electrons.wik...nd-annihilation

http://en.wikipedia....ki/Annihilation

[imatfaal]

IM Egdall, on 19 October 2011 - 03:14 PM, said:

http://en.wikipedia....Pair_production

http://electrons.wik...nd-annihilation

http://en.wikipedia....ki/Annihilation

IME

With respect those links seem to be pair production and annihilation - not gamma-gamma interaction. I didn't read all of them so could you point out the sections that refer to photon interaction with another photon as a physical observed process

[RMX]

I would not say that Matter is made of light, it can be turned into light but light is also just a form of energy. The only way to know what it would really look like would be to winess the big bang. Energy is kinda like something that changed its form so many times it forgot what it originally looked like. Anyways what I'm getting at is while you can say light is pure energy, the same thing can be said for mad so you really can't go saying mass is made of light.

Mad "Mass"

[Andeh]

timo, on 17 October 2011 - 06:40 AM, said:

I think it has already been said that the argument with the mass is not entirely convincing. But it is funny that all what you said is completely correct except for the word "mass". Had you said "electrical charge" or "half-integer spin" then your statement would have been a great argument.

That reminds me of a slightly off-topic thought. I didn't know that this was argued before...
I was considering if photons were neutral in charge or if they were chargeless. They seem to mean the same thing, but by neutral I just mean having negative and possitive charge in equal parts (i.e. a neutron...neutral in charge but with charged constituents that cancel out) and by chargeless, I mean completely without any representation of charge. Since there isnt such a thing as an anti-photon, as there is an anti-neutron, I beleive that photons are chargeless. You seem to beleive the same thing...has this been validated?

This raises the question of how charge arises during pair production. If photons had positive and negative constituents that just canceled out, I would hypothesize that they just "split" during pair production, but they DONT--charge seems to come from nowhere. Perhapse it actually does arise from nowhere. Perhaps it arises so that the system can have time-symmetry, i.e. so that the particle-antiparticle pair can anihillate back into photons. In other words, charge arises because it HAS to.

[DrRocket]

Andeh, on 14 January 2012 - 10:39 PM, said:

That reminds me of a slightly off-topic thought. I didn't know that this was argued before...
I was considering if photons were neutral in charge or if they were chargeless. They seem to mean the same thing, but by neutral I just mean having negative and possitive charge in equal parts (i.e. a neutron...neutral in charge but with charged constituents that cancel out) and by chargeless, I mean completely without any representation of charge. Since there isnt such a thing as an anti-photon, as there is an anti-neutron, I beleive that photons are chargeless. You seem to beleive the same thing...has this been validated?

This raises the question of how charge arises during pair production. If photons had positive and negative constituents that just canceled out, I would hypothesize that they just "split" during pair production, but they DONT--charge seems to come from nowhere. Perhapse it actually does arise from nowhere. Perhaps it arises so that the system can have time-symmetry, i.e. so that the particle-antiparticle pair can anihillate back into photons. In other words, charge arises because it HAS to.

Chargeless and neutral charge are in fact the same thing.

There is such as thing as an anti-photon. It is a photon. The photon is its own anti-particle.

The photon is an elementary particle. It is not composed of other particles.

There is a known symmetry, but it it is not just charge symmetry or time symmetry. It is charge, parity and time symmetry.

Charge does not appear during pair production. Charge is conserved in pair production.

During the usual pair production process, a nucleus is involved. It is not possible for a single photon to produce a pair -- that would violate conservation of momentum. It is possible for two photons to produce a pair.

Rather than just pulling stuff out of the air (or elsewhere) you might want to read a book on elementary particle physics. Introduction to Elementary Particles by David Griffiths is accessible, if somewhat dated (it was written before it was found that neutrinos are massive).

This post has been edited by DrRocket: 14 January 2012 - 11:53 PM

[Widdekind]

What if you liken 'massive' particles, to high-energy photons ? As repeatedly observed, above the various pair-production energy thresholds, e.g. ~1 MeV for e⁺e^-, 'matter' and 'energy' freely inter-convert. Thus, the appearance of distinction, between the two, is an artifact of our "cold", i.e. low-energy, universe (in which low-energy photons lack the energy to "excite" into "mass states"). Accordingly, perhaps the ambient background vacuum, could be analogized, to a Bose-Einstein Condensate ?

[swansont]

Widdekind, on 15 January 2012 - 09:49 AM, said:

What if you liken 'massive' particles, to high-energy photons ? As repeatedly observed, above the various pair-production energy thresholds, e.g. ~1 MeV for e⁺e^-, 'matter' and 'energy' freely inter-convert. Thus, the appearance of distinction, between the two, is an artifact of our "cold", i.e. low-energy, universe (in which low-energy photons lack the energy to "excite" into "mass states"). Accordingly, perhaps the ambient background vacuum, could be analogized, to a Bose-Einstein Condensate ?

!

Moderator Note

I will ask again that you not hijack threads with your speculations and off-topic questions.

[Widdekind]

In the book Quarks, by Nambu, the author says that the theory of the Higgs field, likens space, to a "super-conductor", i.e. a Bose-Einstein Condensate. I want to understand, what the author is implying, e.g. "space is like a BEC, with a ~1MeV band gap, between the ground state, and lowest available excited state"? I'm trying to understand Nambu's book Quarks, about whose analogies, I may be confused.

This post has been edited by Widdekind: 16 January 2012 - 02:51 PM

[Klaynos]

Widdekind, on 16 January 2012 - 02:51 PM, said:

In the book Quarks, by Nambu, the author says that the theory of the Higgs field, likens space, to a "super-conductor", i.e. a Bose-Einstein Condensate. I want to understand, what the author is implying, e.g. "space is like a BEC, with a ~1MeV band gap, between the ground state, and lowest available excited state"? I'm trying to understand Nambu's book Quarks, about whose analogies, I may be confused.

!

Moderator Note

When a mod tells you not to hijack threads by interjecting off topic posts, do NOT just do it again in the following post. Actually NEVER do it again. It is not appropriate and against our rules.

[Andeh]

DrRocket, on 14 January 2012 - 11:49 PM, said:

Chargeless and neutral charge are in fact the same thing.

There is such as thing as an anti-photon. It is a photon. The photon is its own anti-particle.


The photon is an elementary particle. It is not composed of other particles.

There is a known symmetry, but it it is not just charge symmetry or time symmetry. It is charge, parity and time symmetry.

Charge does not appear during pair production. Charge is conserved in pair production.


Rather than just pulling stuff out of the air (or elsewhere) you might want to read a book on elementary particle physics. Introduction to Elementary Particles by David Griffiths is accessible, if somewhat dated (it was written before it was found that neutrinos are massive).

I understand that a photon is it's own antiparticle. Correct me if I'm wrong, but that's quite different than there being an antiparticle that is a different particle entirely.

I never claimed that a photon wasnt an elementary particle. I was comparing it to a neutron in a different way. I'm not completely ignorant of all this.

If chargeless and nuetral charge are the same thing, could you explain why neutral elementary particles are their own antiparticle (unlike neutral "composite" particles)?

I don't thing you understood my point. "Charge is conserved during pair production", in other words, the 2 photons are neutral before pair production, and the electron-positron pair are neutral after pair production, since their charges cancel out. But why should the electron and positron even have charge? Why can't 2 neutral photons produce 2 massive, neutral particles?

Thank you for the suggestion. I've already bought the book and will begin it as soon as I finish this post.

[swansont]

Andeh, on 17 January 2012 - 12:33 AM, said:

I don't thing you understood my point. "Charge is conserved during pair production", in other words, the 2 photons are neutral before pair production, and the electron-positron pair are neutral after pair production, since their charges cancel out. But why should the electron and positron even have charge? Why can't 2 neutral photons produce 2 massive, neutral particles?

You can create two neutral particles in pair production. Electrons/positrons are simply the least massive pair accessible via the electromagnetic interaction, and if you are using photons, you have to constrain yourself to an EM interaction.

[DrRocket]

Andeh, on 17 January 2012 - 12:33 AM, said:

But why should the electron and positron even have charge?

If they didn't have charge they wouldn't be an electron or a positron.

Andeh said:

Why can't 2 neutral photons produce 2 massive, neutral particles?

See swansont's post. Apparently they can.

One cannot say with certainty exactly what particles are produced in a given interaction. That is the nature of quantum theory. It only predicts probabilities. While one outcome may predominate, other outcomes may occur with less frequency. I am not sure of all the possibilities of a gamma-gamma interaction. But unless the energies are quite high, nothing is produced since one must conserve a number of quantities including mass/energy, charge and momentum. Electrons and positrons have the attractive feature that the mass/energy requirement is relatively small among particles with positive rest mass -- and it takes a LOT of energy to produce much rest mass.

[Widdekind]

swansont, on 17 January 2012 - 01:14 AM, said:

You can create two neutral particles in pair production. Electrons/positrons are simply the least massive pair accessible via the electromagnetic interaction, and if you are using photons, you have to constrain yourself to an EM interaction.

Is the photon's "obliviousness", to the Weak interaction, what "shields" photons, from decay, into neutrinos, i.e. ? Otherwise, if neutrinos mass <1eV, then every photon more energetic than infra-red would be unstable to neutrino decay ?