Year 12s: what will be the first way you research your future options? >>

Dark Energy & The Fate Of The Universe

I can't really get which is the answer. Any help please?
http://imgur.com/mtPFrpH

If Dark energy is increasing the rate at which the universe expands, that means that it took the universe less time than we previously thought to expand to the size that it is today. Therefore, I personally, would pick answer D

Reply 2

DanielDaniels

Original post by Jillo234

Yeah that makes sense.
Can i ask what's the difference between dark matter and dark energy?

Reply 3

Ceryni

Original post by Daniel Atieh

Yeah that makes sense.
Can i ask what's the difference between dark matter and dark energy?

The accelerating rate of expansion of the universe is posited to be caused by dark energy. Dark matter was theorised due to observations of the rotations of galaxies which found that they were rotating faster than expected; this meant that the galaxies must contain more matter than we can observe currently. Therefore, dark matter doesn't absorb, reflect or emit any type of EM radiation.

Reply 4

DrQuantum

Younger then we thought as we look at the recessive velocity of a galaxy some distance from us and divide that distance by the velocity to find a value for the time where that galaxy was where you are (age of the universe), as the velocity now is not the average and is instead higher your denominator will be larger and so age calculated will be smaller, whereas if you took the smaller average (assuming constant acceleration) you would get an older age of the universe.