Dark energy, Hubble Constant, expansion of the universe, and much much more!?

Question

Its not the galaxies flying away from each other but the space in between the galaxies expanding. The Hubble Constant is 7.01 (km/s)/Mpc meaning for every megaparsec 7.01 kilometers of space are created every second. So, space is like microorganism population growth... it grows exponentially because every created unit of space helps create more.

Correct me if any of that is wrong, here are my questions:

Is this what constitutes dark energy or is the idea of space creating more space separate?

If space isn't creating space than that means dark energy is being created along side it otherwise dark energy would be thinning correct?

Since time factors into the creation of space and space is affected by gravity does the growth of space slow down when near massive objects like black holes?

Answer 1

The Hubble constant is actually 70.1 kms per megaparsec.  This was determined by the Hubble space telescope in 1997 by observing cepheid variables in distant galaxies (named Hubble because that was its primary mission).  In 1998, it also discovered that Type Ia supernovas in those distant galaxies were dimmer than they should have been, suggesting that the universe is expanding faster now than it was in the past.  Some anti-gravity force would be required to accelerate the expansion of space, and is yet unseen; so they called it dark energy.  That's about all I know for sure.  It is believed to be a propery of space itself, however, and it is possible that dark energy increases as space expands, resulting in space that is not only accelerating, but accelerating exponentially.  According to cosmologists, this would result in the destruction of the universe in only 20 billion years.

EDIT -- typo, I meant 70.1 kps per megaparsec (kilometers per second per megaparsec).  That's 70.1 kilometers per second expansion of space for every additional one million parsecs.

Answer 2

Dark energy is still just a suggestion - a conjecture.. there are no sound theories yet (in the mathematical sense).

Space is still making more space as you point out.  The average amount of energy in a given volume remains the same after that volume has expanded (because the light gets stretched by the same amount) and so as no work is done, no energy is lost. (Actually, my personal conjecture is that it is the cosmic background radiation that is pushing space apart.. and as it HAS done work, that is exactly matched by its reduction in energy).

The above explanation (not my pet conjecture) is why there is no 'dark energy' being thinned.

The expansion of space is not getting slowed down by mass.  It is as if the mass is just sliding back over it.. rather like the trick of pulling a table cloth from underneath the crockery and glasses etc..

Answer 3

the fact that space is expanding is a well known fact, but that in itself is not dark energy. dark energy is what scientists have dubbed whatever is causing the universe to accelerate instead of slow down.

EDIT: and it is 70.1 km/s/Mpc