The Big Bang and Relativity

[Didaskomenos]

I have a friend who pointed me to this article http://aolsvc.news.aol.com/news/arti...1309990017&cid

It's the study that said that the universe inflated in less than a trillionth of a second. My friend then demands to know how all that mass could have travelled faster than light. My non-scientific hunch is that the travelling must occur relative to light, and since light was actually a part of the expanding universe and hence was moving at its own relative speed within the universe, there is no problem. Should I stay out of physics? Or should my friend? Or both?

 

[GoSeminoles!]

My hunch is that you are right, more or less. The inflation they are talking about is a stretching of space-time, not a traveling of particles and waves from one place to another. I don't know what the laws of physics have to say about the upper limit of space-time expansion.

 

[jwu]

My friend then demands to know how all that mass could have travelled faster than light.

It didn't - it was an expansion of space, not an explosion with matter flying around.

 

[Lucretius]

Yup, as everyone has said before: the C-limit is for mass in space. Not space itself.

 

[Loudmouth]

I have a physics noob question.

Would this sudden expansion of spacetime also increase the wavelength of energy present in the early universe? Or, did the energy act as a particle so that the wavelength did not increase but distance between quanta increases.

And finally, how does this relate to the temperature of the CMB? Is the low temp of the CMB related to loss of energy over time or the expansion of spacetime.

 

[Lucretius]

I have a physics noob question.

Would this sudden expansion of spacetime also increase the wavelength of energy present in the early universe? Or, did the energy act as a particle so that the wavelength did not increase but distance between quanta increases.

And finally, how does this relate to the temperature of the CMB? Is the low temp of the CMB related to loss of energy over time or the expansion of spacetime.

Well, as space expands, the speed of light approaching us seems to slow. The formula v=lambda (f) describes light, where lambda is the wavelength and f is the frequency and v is the velocity. f stays the same, v slows down, therefore lamda goes up (aka we see a redshift!)

Temperature of course is related to Pressure and volume. The more volume and less pressure, the colder the universe will be.

 

[Didaskomenos]

Thanks, guys. I think the point is made.