Obligatory Monthly Plug Drug's Philosophical Ramblings Thread

[Plug Drugs]

It's not just that but how a particle reacts to travelling through that dark energy actually determines what that particle actually is. I do not think mass can travel at the speed of light... "The same theory says that objects gain mass as they speed up, and that speeding up requires energy. The more mass, the more energy is required. By the time an object reached the speed of light, Einstein calculated, its mass would be infinite, and so would the amount of energy required to increase its speed. To go beyond the infinite is impossible.
So for mass to actually travel at the speed of light it would have to have zero rest mass (light has zero rest mass which is why it is the universal speed limit) so no I do not think mass as we know it could travel AT the speed of light. Close to at best but never AT it. It would have to be something other than matter (as we know it in this universe) for it to travel as fast as or faster than the speed of light.

But with the model of an accelerating universe, it's going to happen -- at some point on that exponential curve, the speed of the matter expanding will surpass the speed of light; of course the matter will annihilate itself right before it reaches the speed of light though. And if dark energy's density decreasing is what's causing the universe to accelerate, then it means that the particles aren't picking up more energy causing them to accelerate (which would make them more massive), but rather they travel greater distances from the same kinetic energy they already had.