What the theories of Physics allude to particles?massles how did they figure that?

Question

Did they photograh these massless gysmos what ever they are,do they have volume in order to exist?If so how big are they?

Answer 1

The equation E = m c^2 doesn't simply say:
"creation of matter requires energy, and creation of energy requires matter"
it says energy and mass are equivalent concepts.
With this understood, there exist no massless particle, there are only particles with zero REST MASS, which is when their velocity is zero or more precisely ,when their energy is zero.
So when we say, a particle with zero rest mass is moving with the speed of light, it means that energy is traveling with that speed and from it's equality with mass, we consider it as a particle. This also means that they occupy no volume.

Answer 2

According to Special Relativity, any particle travelling at the speed of light must have a zero rest-mass. This is a consequence of the Lorentzian structure of flat spacetime with the speed of light as the limiting speed. The momentum of any particle is (c=1 units)

mv/sqrt(1-v^2).

When v=1, m=0 otherwise the momentum of the particle is infinite (which would violate all experience--imagine being knocked flat by a ray of sunlight).

The infinite Lorentz length contraction you'd expect for something moving at the speed of light would suggest that the photon is 2-dimensional, and indeed this prediction agrees with the fact that there are only two spin states of the photon, despite the fact that it is a vector (spin=1) particle. It's kind of silly to think this way of a photon's geometry however, because it is not like a tennis ball--it's a quantum mechanical particle which (in a pure momentum state) will be completely unconfined and "wavelike".

Answer 3

Massless particles *must* travel at the speed of light, so that fact alone would make them impossible to photograph. If they have no mass, they also have no volume. Calling something a massless particle does seem weird, since the word particle implies something with mass. So I can see where one might get confused.

Even though they don't have any mass, they can be detected. Photons are massless, but our eyes detect them no problem. So long as a particle (massless or not) *interacts* with matter (by moving it, or changing it somehow) then we can detect it. On the flip side, neutrinos are tiny (but not massless) particles that hardly interact with matter at all, so they are very hard to detect. in fact, millions of neutrinos pass through you body every second, but they don't interact with any of your atoms, so they cause no harm.

Answer 4

They are packets of energy like the photon.