We generally think of space as a vacuum consisting of "nothing".
Yet we know that space has properties.
Space (a component of space-time)3:
- expands (at an accelerating rate), diluting matter & radiation4;
- is warped by massive bodies;
- can be rippled by catastrophic gravitational events1
- has a temperature (which is cooling);
- has intrinsic vacuum energy;
- creates particle pairs out of "nothing";
- is intimately linked with time;
- stretches (redshifts) light wavelength as it expands; and
- possesses a constant universal speed limit which only electromagnetic waves and massless particles can equal and which only the expansion of space itself may exceed.2
If space has properties like these; and if it can be described by cosmologists in mathematical terms, then it is clearly not what we used to think of as "nothing"; and I have a growing tendency to think that it must be "something".
So what is it?
Can Cosmologists describe what space is, in laymen's terms?
1 added 9th April 2014 . Confirmed by Ligo first detection of gravity waves. Predicted 1916 by Einstein, detected 14th September 2015, announced by Ligo 11th February 2016.
2 amended 9th April 2014.
3 amended 31st December 2016.
4 amended 5th August 2017.