Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Yasser on 11/11/2009 11:30:02

Title: At what speed did space expand during the Big Bang?
Post by: Yasser on 11/11/2009 11:30:02

Yasser  asked the Naked Scientists:
   
Dear Naked Scientists,

If the "Big Bang" Theory is to be believed, what was the speed at which space and or matter itself expanded?

Surely this has to be faster than the speed of light, as to observe light there has to be space?
 
-Yasser in Canada

What do you think?

Title: At what speed did space expand during the Big Bang?
Post by: Vern on 11/11/2009 11:51:17

The theory is that a period of inflation happened, during which the laws of nature did not apply. Inflation was much faster than the speed limit of light would allow. But even in present times many suspect that the universe is expanding and that the expanding is not governed by the speed limit of light. The idea is that space itself is expanding and carrying light along with it, stretching the light and causing the red shift we see.

I would be embarrassed if someone thought I believed such silly nonsense; but it seems to be what most scientists believe.

Title: At what speed did space expand during the Big Bang?
Post by: PhysBang on 11/11/2009 15:28:24

Inflation is a concept that not every standard cosmologist accepts. However, even in a standard cosmological model without inflation, the early expansion of the universe was much faster than the speed of light and tapered off gradually. The general theory of relativity allows for there to be an expansion of space that is faster than the speed of light, because this is not actually motion, at least motion as defined under the speed-of-light limit defined in special relativity.

Title: At what speed did space expand during the Big Bang?
Post by: Mr. Scientist on 12/11/2009 01:54:43

Quote from: Vern on 11/11/2009 11:51:17

The theory is that a period of inflation happened, during which the laws of nature did not apply. Inflation was much faster than the speed limit of light would allow. But even in present times many suspect that the universe is expanding and that the expanding is not governed by the speed limit of light. The idea is that space itself is expanding and carrying light along with it, stretching the light and causing the red shift we see.

I would be embarrassed if someone thought I believed such silly nonsense; but it seems to be what most scientists believe.

As I understand the question, the person is asking what was the ''initial expansion speed'' - inflationary phase occured after the big bang, but not too long after. Before the superluminal stage, space and time expanded at the speed of light. This does not violate relativity, as much as it does not violate it when it moves at superluminal speeds.


In a sense, space expanded, sped up, slowed down and now is expanding at an exponential superluminal rate again. It's almost like cyclic periods of luminal and superluminal changes.

Title: At what speed did space expand during the Big Bang?
Post by: Mr. Scientist on 12/11/2009 01:55:21

Quote from: DiscoverDave on 11/11/2009 16:48:25

Ludicrous speed

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2F3.bp.blogspot.com%2F_PNVfoGbhv5U%2FSPR4bPJcUMI%2FAAAAAAAAAO0%2F6Nb2DpeoguQ%2Fs400%2FSpaceballs_Dark_Helmet.jpg&hash=8a5ba5f6963b1ae0928d25d37d3f94d8)
My brains are going into my feet!

 

Lol.

Love spaceballs.

Title: At what speed did space expand during the Big Bang?
Post by: Schelli on 15/11/2009 23:19:36

haha, i immediately had to think of spaceballs too :)