Will the Universe End in a Big Crunch?

[jacksdvds]

And you know this how?

 

[Chalnoth]

And you know this how?

Anything that moves faster than light emits radiation. If it's a charged particle, it emits Cherenkov radiation. This is observed, for example, when high-energy particles move through mediums faster than the speed of light in those mediums. If it uncharged, there are other, similar processes (they're slower, but still occur). So not only would anything moving faster than light be very much observable, it would rapidly cease to move faster than light as it loses energy.

That, or it's a tachyon, in which case the extra emission will just cause it to gain speed and emit more radiation, which would cause the universe to explode. As I mentioned.

 

[bill alsept]

Just because we can't see it doesn't mean there is not a speed faster than light!

I always wondered if there was nothing faster than light then why do we have black holes? What does it mean need an escape velocity faster than light?

 

[alexg]

I always wondered if there was nothing faster than light then why do we have black holes? What does it mean need an escape velocity faster than light?

It means once you check in, you don't get out.

 

[jacksdvds]

Anything that moves faster than light emits radiation. If it's a charged particle, it emits Cherenkov radiation. This is observed, for example, when high-energy particles move through mediums faster than the speed of light in those mediums. If it uncharged, there are other, similar processes (they're slower, but still occur). So not only would anything moving faster than light be very much observable, it would rapidly cease to move faster than light as it loses energy.

That, or it's a tachyon, in which case the extra emission will just cause it to gain speed and emit more radiation, which would cause the universe to explode. As I mentioned.

Hence, it has been observed "when energy particles move through mediums faster that the speed of light", supposes that there is a speed FTL. Your very words!

Secondly, energy moving through a medium, perhaps a flash light beam through a fish tank, the speed of the light beam on the emerging beam would then be slower than light speed due to the lost energy. Now we have a second argument and a second speed of light.

It strike me as though you are arguing both sides of the issue. Correct me if I mistook your words.

 

[alexg]

Hence, it has been observed "when energy particles move through mediums faster that the speed of light", supposes that there is a speed FTL.

Light moves through mediums other than the vacuum at less than c.

the speed of the light beam on the emerging beam would then be slower than light speed due to the lost energy.

When the beam emerges from the medium back into the vacuum, it travels at c. Lost energy shows up as a lowering of the frequency.