Recent content by backward

For one thing, antiparticles have been interpreted as particles going backwards in time.

It means that just as you can and often go back in space cordinates, you go backwards in time coordinate. This is allowed by the laws of Physics with some exceptions. I cannot think of a specific physical process which would trigger time-reversal. So, it is a general statement. Only point I...

For all we know it may be happening without our knowledge. After all, barring some processes in weak interactions etc there is nothing to prevent time from going backwards.

But if today's elementary particles are extended objects with smaller things inside, what are those things--pointless or extended? Ultimately either we must accept point particles or have extended objects which are not rigid. If elementary particles are extended and rigid, we have another...

If somehow time reversed direction and we went into our past (this is different from time travel through closed time like circuit), we would not notice anything strange because as we go back in time our corresponding memory also will be lost. So we will feel exactly like when we were there at...

Are Unruh radiation and Hawkins radiation manifestations of the same basic phenomenon?

Thanks again.

Another way of posing the question which was in my mind is: According to QP, a particle with precisely known momentum will have infinite uncertainty in its position. A monochromatic photon would then be impossible to locate anywhere. I do not know in what sense this could be true. I know I am...

Not all bosons are massless. Mesons are bosons and have a mass. But, of course, all bosons are volume less, since they are not subject to Pauli's dxclusion principle.

Thanks a lot PeroK

After destruction, the particle doesn't exist. So it's momentum has no value, which is different from having a value equal to 0.

Thanks. I understand that the best way to describe QP is mathematical; but I was trying to get as much coceptual clarity as possible. Does it imply that a traveling electromagnetic wave cannot be represented by a particle traveling with velocity c subject to HUP? Of course I realize that as one...

Let a photon of a definite wavelength (hence a definite momentum ) start it's journey at time 0. After 8.3 minutes it hits a detector on earth. So it's position is exactly known (in fact it can be predicted for any time less than 8.3 minutes). So we have particle with definitely known momentum...

I have a question. In a massive star (more than say 5 times the mass of the sun), the electron/neutron degeneracy pressure is unable to prevent the gravitational collapse. Does this imply that the Pauli's exclusion principle breaks down and two or more electrons/neutrons collapse to the same...

I quote from the thread http://preposterousuniverse.com/writings/cosmologyprimer/faq.html#energy Is energy conserved in an expanding universe? This is a tricky question, depending on what you mean by "energy." Usually we ascribe energy to the different components of the universe (radiation...