Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 23/09/2016 13:53:01

Title: How did matter travel at faster than light immediately after the big bang?
Post by: thedoc on 23/09/2016 13:53:01
Luke Pullar asked the Naked Scientists:
   How did matter travel at faster than light immediately after the big bang?
What do you think?
Title: Re: How did matter travel at faster than light immediately after the big bang?
Post by: evan_au on 24/09/2016 10:55:49
I assume that you are talking about Inflationary theory? This is a period after the Big Bang that is thought to have lasted about 10-33 seconds.

The cause is still a mystery, but as always, there are plenty of theories:
https://en.wikipedia.org/wiki/Inflation_(cosmology)#Theoretical_status
Title: Re: How did matter travel at faster than light immediately after the big bang?
Post by: puppypower on 24/09/2016 11:40:49
Matter cannot travel the speed of light. We infer the motion of matter, from energy signals. We cannot measure the motion of matter directly at distances beyond our solar system. Matter appearing to move faster than light, as inferred by an energy signal, would suggest their must be other ways to tweak energy signals, to create such optical illusions.

In a more formal way; If you plug velocity V>C, into the equations of special relativity, you end up dividing mass, time and distance by the square root of a negative number. This result are imaginary numbers. See below.

(https://wikimedia.org/api/rest_v1/media/math/render/svg/abacf009fa4db767f015172584c8fc89e7725745)
Title: Re: How did matter travel at faster than light immediately after the big bang?
Post by: Bill S on 24/09/2016 22:48:59
Would it not be the case that matter remained stationary in expanding space? 
Title: Re: How did matter travel at faster than light immediately after the big bang?
Post by: evan_au on 24/09/2016 23:39:58
Quote from: puppypower
We cannot measure the motion of matter directly at distances beyond our solar system.
The Gaia spacecraft was the subject of last week's Naked Scientists podcast.
It's goal is to directly measure the position and motion of a billion stars in our part of the milky way galaxy, using parallax and high-resolution spectroscopy.
Their first data release occurred earlier this month, containing an initial 2 million stars.

See: https://en.wikipedia.org/wiki/Gaia_(spacecraft)