Where is the constant? - Page 2

topsquark · Oct 9th 2013, 09:54 AM

Originally Posted by RelativityIsWrong

I don't yet have the mathematical wherewithal to understand that... but what I think it is is this:
First, acceleration - due to both leftover from the inflationary period and the dark energy - slows down because the positive gravity is stronger at that range than the dark energy's negative gravity.

"Positive gravity?" "Negative gravity?" Anyway, the rate of Universal expansion is accelerating as we speak. It is not slowing at all.

Originally Posted by RelativityIsWrong

But at a certain distance, because dark energy is constant everywhere, but matter isn't, the dark energy's negative gravity becomes more than the positive gravity. And then it starts to accelerate again after passing this threshold.

"Dark energy is constant everywhere?" Dark energy appears to be the tendency of "free space" to expand. The idea is that in the space between galaxies there is quite a lot of expansion going on. (This also means that, theoretically, the space inside the atoms in your body is also expanding. Thankfully this is not measurable!) Dark energy is indeed spread about the Universe but for some reason is not as strong in regions where there is mass. So it is by no means "constant."

-Dan

topsquark · Oct 9th 2013, 09:57 AM

Folks this has all been fun and all, but there are an awful lot of "I think" and "I believe" in here. This is the Theoretical Physics forum and I don't see any theoretical conversations going on here...these would imply terms like "I calculated" or "Based on this evidence" and such. Please keep the "I think" statements to the Lounge.

I would simply move the thread but I think there are enough of these concepts already being spoken for in the existing threads there so nothing is going to go missing.

Thread closed.

-Dan