SciContest! Why can't matter be made of photons?

[prometheus]

So what happens when matter, say a bunch of electrons, accelerates past c, into a BH?

Matter can't accelerate past c.

I can be quite dogmatic about this, so apologies to everyone I talk to about it, but the concept of relativistic mass is crap! The example of the photon is perfect - you can say that because a photon carries momentum that is must have a mass, and that mass is it's dynamical mass. If you think like this you will tie yourself in knots because relativistic mass is not a mass, it's an energy. Now I can practically hear you all shouting "mass and energy are equivalent" and you're (almost) right - mass is a form of energy but energy is not necessarily a form of mass. Mass is a very special form of energy that has particular properties - it causes a coupling to gravity and any object that has mass is constrained to travel at speeds less than c for example. A photon has energy but no mass, hence it travels at c and doesn't couple directly to gravity.

Photons do interact with gravity indirectly. One of my office mates is working on how curved spaces affect light propagation and the way it works is that you have photon self energy diagrams that look like this:

A graviton can nip in and interact with the electrons in the loop, which has weird effects on the propagation of the photon.

 

[Vkothii]

Mass is a very special form of energy that has particular properties - it causes a coupling to gravity and any object that has mass is constrained to travel at speeds less than c

Nonetheless, Einstein tried and failed to prove that matter (with mass) can't collapse past an EH, or beyond a certain radius, for the reason stated: matter can't have a velocity that exceeds c.
Except GR predicts that it does anyway. So now what?

 

[Vern]

Photons do interact with gravity indirectly.

Everything I've seen indicates that photons have a direct relationship with gravity.

 

[Vkothii]

Doh! :bugeye:

 

[Reiku]

Who is willing to have a go at undoing this a bit and seeing if it goes back together? What mechanism might he be talking about? "In a way that" some field binds particles isn't all that illuminating.
BTW I didn't find the word "photon" on this webpage.

Vkothi

Where is the post that you qouted here?

''“ Originally Posted by Albrecht Giese.
If two particles are bound to each other in a way that the binding field enforces a specific distance then, at every change of the position of one of them, it needs a finite time caused by the finite speed of light to make the other particle moving. This delay is sufficient to explain the inertial behaviour.

It turns out that the inertial mass of an elementary particle is given by the universal equation

Also the relativistic increase of mass at motion and as a consequence the mass energy equivalence (Einstein) is perfectly explained by this mechanism.

--www.ag-physics.org/rmass/ ”


It's just that i have looked about... can't seem to find it.

I wouldn't agree with him. The time it takes for such a thing, may as well be $$0<t<r/c$$, and alone, cannot answer for the mechanism.

I believe the inertial effects are in fact a phenomenon after the change, and only the direct evidence of a particle with matter trying to move through the vacuum.

The increase of motion in relativistic formulaes, is evidence that an inertial body cannot travel at it's cousins speed c, but not the direct mechanism itself.

It may be that mass is in fact caused by an ''inert'' force on the inner charge of a particle (the electromagnetic force), inherent in all known particles. This coupling is in fact caused by the zero-point energy, an all-pervading force in the vacuum, that would drag on the inner properties of the particle that is experiencing inertial effects.

 

[AlphaNumeric]

Nonetheless, Einstein tried and failed to prove that matter (with mass) can't collapse past an EH, or beyond a certain radius, for the reason stated: matter can't have a velocity that exceeds c.
Except GR predicts that it does anyway. So now what?

Ni, it doesn't and he didn't.

 

[Vkothii]

OK what happens to it?
And who didn't what, Einstein was right - matter can't get past the radius after all?

You're saying Einstein's objections stand, there is no way a BH can form; so the explanation for them is something that isn't to do with relativistic matter?

 

[BenTheMan]

Photons can't accelerate and matter can.

New entry after four pages of you guys bickering!

Simon Anders says that photons can't accelerate.

This is certainly a valid statement in free space, but what about light bending in a gravitational field. Shouldn't there be a centripetal acceleration (I really don't know the answer to this *gasp*). Also, what about when a photon moves from free space to, say, glass. It gives off Cherenkov radiation as it slows down, right?

 

[BenTheMan]

Why can't matter be made of photons?

Does it really matter?

/cough /cough


Kadark

 

[BenTheMan]

Ok. I just drove from Texas to Ohio so I've been out of the loop for a few days, and I'm going to lock this thread and do some, ahem, housekeeping.

Competition isn't closed for good! Just closed for cleaning!

 

[BenTheMan]

Late entry: Photons are not subject to the Pauli exclusion principle. Matter is.

Good one! I think this has already been covered by temur, though, because whether a particle obeys the exclusion principle or not depends on the spin of the particle.

 

[BenTheMan]

and ordinary matter would quickly decay into photons if its was simply composed of bunches of them.

Has anyone said this yet?

This is a good one. Absent some confinement mechanism, which is difficult to imagine because photons don't interact with each other, theories claiming to explain everything as a bound state of photons are meaningless.

 

[BenTheMan]

Let's recap:

Entry #1: from ashura
Layman entry: Matter has mass. Photons are massless. Ergo, matter can't be made of photons.

CptBork pointed out that ashura REALLY means rest mass.

Entry #2: from Diode - Man
Photons are products of excited (heated) atomic matter. The wave frequency (beats or waves per second) of the photons of white light are so high that it can reach 400 to 790,000,000,000,000 waves per second! (Tera-hertz frequency)

With such erratic motions it would be impossible for a photon to become a solid or permanent piece of any molecular or atomic configuration. If in a laboratory, one attempted to forcibly make a photon join in with say a particle of Earth dirt, the photon would just bounce away unable to be joined with the solid matter. It may be the case because the photon cannot be contained in a magnetic field.

Ultimately however, like electricity, we can only know what a photon DOES and not what constructs it, it is I believe, what I'm going to term a "base unit" of the Universe.

(I am a "layman"... have I come close on my statements? ) ”

Entry #3: from Steve100
If two particles with the same mass are made of photons, they must be made of the same amount of photons.
This would make the 2 particles have identical properties, and we already know that we can have particles with different properties and the same mass.
Therefore the particles cannot be made of photons.

mass = relativistic mass

Entry #4: from QuarkHead (in limerick form)
A physicist (mad as a hatter)
Once pondered the nature of matter.
He concluded "it's light";
But we know that's not right,
Since the absence of forces
Would take less than two horses
To cause all matter to shatter.

Entry #5: from melodicbard
Photon does not have charge.
Matter can carry positive or negative charge.

Entry #6: from Vkothii. I think I missed this one before.
Photons are perturbations in the EM field and don't couple to the putative Higgs field.
Like waves on the surface of a liquid are perturbations of the surface, and don't displace (carry) any liquid, except as part of the momentum-wave's [vertical] time-displacement. Ocean waves don't have mass either.

Particles like electrons, can 'surf' a wave, like a bit of wood or a surfer can surf an ocean wave. That's an interaction with the wavefront - a charged electron is affected by the electric wave component of a coherent group of photons.

Fundamental particles with 'rest' mass [can] couple to both fields.
A photon doesn't generally interact with another photon, except at the extreme of the frequency range, where two 'extreme' photons with sufficient momentum have a greater probability (the uncertainty principle) of massive (gamma-gamma) interaction when they encounter each other, and interact as massive particle-antiparticle pairs, but not as photons.

Something like that.

Entry #7: from Cyperium
Why can't mass be made of photons?

Photons are the result of the energy released when mass converts or when something of higher energy enters a lower state (then the energy difference is released as photons to preserve the energy total)

So photons preserves the energy, so then there is no need for preservation in the form of photons, if the energy is already preserved in mass.

You can convert photons to mass, or mass to photons. But photons cannot be mass.

Entry #8: from Janus
Why matter can not be made up of photons.

Argument:

The radius of the Electron is less than 10^-13 m
The mass of the Electron is 9.1e-31 kg
The energy equivalence of the mass of an electron is 8.14e-14 joules
The wavelength of a single photon with the energy equivalence of the mass of an electron is 2.43e-12 m, about 10 times the diameter of the electron.

Ergo, for an electron to be made up of a single photon, it would have to be made up of something larger than its own diameter.

Trying to have the electron being made up of more than one photon makes the problem worse. Each photon would have to have a fraction of the energy equivalence of the electron, and as the energy of a photon decreases, its wavelength increases.

Entry #9: from...Vern?
BenTheMan; an entry. In all of the photon theories I can find, not one of them can make a neutrino out of photons. Maybe it is not fair; you posted this yourself But I have known it for years.


Entry #10: from temur
Have somebody already said spin? Photon has spin 1, and you cannot make particles with spin 1/2 with this.

Entry #11: from CptBork
and ordinary matter would quickly decay into photons if its was simply composed of bunches of them.

==================================================

If I have missed any, let me know. I am opening the thread again because I have finally caught up to speed. There IS some good discussion going on here, which is what I was shooting for.

 

[Vern]

This is a good one. Absent some confinement mechanism, which is difficult to imagine because photons don't interact with each other, theories claiming to explain everything as a bound state of photons are meaningless.

The confinement mechanism can be the electric field and resonance. The electric field is generated any time a photon bends it path. Resonance when it is bent so much that front meets back in one wavelength. These are my suspicions

 

[Vern]

Ergo, for an electron to be made up of a single photon, it would have to be made up of something larger than its own diameter.

I think we covered this before but there has never been anything about an electron discovered that exists at a radius less than the classic electromagnetic radius of the electron.

The assumption was that since nothing was found, the electron must be smaller. I don't think that is good reasoning.

 

[Vkothii]

...a photon bends it path

Why would a photon "bend", why does it have a path?

 

[Vern]

Why would a photon "bend", why does it have a path?

The bending can be caused by interference from another photon. Its path is how it gets from one place to another. If it gets there via a curve, its fields can not be symmetrical. The fields on the outside of the bend must have more area. This can show up as an electric field. I suspect

 

[BenTheMan]

I think we covered this before but there has never been anything about an electron discovered that exists at a radius less than the classic electromagnetic radius of the electron.

The assumption was that since nothing was found, the electron must be smaller. I don't think that is good reasoning.

The point is that the Compton wavelength of the electron is orders of magnitude LARGER than it's classical radius. Let's assume that the electron WERE made of a photon. This means that the electron should exhibit structure on the order of the wavelength of the photon. Because the electron exhibits no such structure on that scale, the electron must be SMALLER than it's classical radius. You (Vern) and Reiku have both said this in your own words. This means that the wavelength of the photon MUST be smaller than the Compton wavelength of the electron, which means that one cannot get the electron mass right if you want to make it of photons.

Again, I don't want to make a habit of explaining others' ideas, but I don't see Janus around all that often.

 

[BenTheMan]

Likewise, one could use the same arguments about neutrinos.

Up to factors of hbar and c, the compton wavelength of a particle looks like

$$\lambda \sim \frac{1}{m}$$

This means that something with a very tiny mass (neutrinos) have a huge Compton wavelength. Bonus points to Janus if (s)he can put factors of hbar and c into the above expression, and show HOW huge the compton wavelength of a neutrino (mass ~1 eV) is.

 

[Vern]

This means that the wavelength of the photon MUST be smaller than the Compton wavelength of the electron, which means that one cannot get the electron mass right if you want to make it of photons.

I've seen this argument, but it does not consider the confinement pattern that a photon would contort within, which is not known.