Dark Matter And Dark Energy

 

Dark matter and dark energy

Formation of dark energy

–         When the universe formed after the big bang theory. It started as a small ball of energy, began expanding, and still continues.

–         However, the thing that puzzles scientists are that instead of the expansion slowing down its rate is increasing, going against normal physics.

 

Formation of dark energy

–         This explains the occurrence of energy causing the expansion which scientists term as dark energy.

–         According to scientists 68% of the universe is dark energy, 27% is dark matter and only 5% is what we currently can observe.

–         The theory to this was first given by Einstein’s long-forgotten gravity theory which consisted of a cosmological constant.

 

Why is there dark energy?

–         Scientists have now given 3 explanations for dark energy:

–         The first is of course Einstein's theory of gravity.

–         a new theory could include some kind of field that creates this cosmic acceleration. 

–         Another explanation for how space acquires energy comes from the quantum theory of matter. In this theory, "empty space" is actually full of temporary ("virtual") particles that continually form and then disappear. 

 

Dark matter

–         Originally known as the “missing mass,” dark matter’s existence was first inferred by Swiss American astronomer Fritz zicky, in 1933 

–         In the late 1970s, astronomer Vera Rubin made the surprising discovery of dark matter.                                                                             she was studying how galaxies spin when she realized the vast spiral Andromeda Galaxy seemed to be rotating strangely.

–         It is this dark matter that holds all galaxies together.

 

–         The dark matter by definition does not interact electromagnetically (i.e., with light) – it’s dark!

–         More is unknown than known: 

–         Firstly, it is dark, meaning that it is not in the form of stars and planets that we see. 

–         Second, it is not in the form of dark clouds of normal matter, matter made up of particles called baryons because we would be able to detect baryonic clouds by their absorption of radiation passing through them. 

–         third, dark matter is not antimatter, because we do not see the unique gamma rays that are produced when antimatter annihilates with matter.

–         Finally, we can rule out large galaxy-sized black holes.

–         It is important to note that dark matter is a form of matter.

–         At this point, there are still a few dark matter possibilities that are viable. The baryonic matter could still make up the dark matter if it were all tied up in brown dwarfs or in small, dense chunks of heavy elements. 

–         These possibilities are known as massive compact halo objects, or "MACHOs".

–          But the most common view is that dark matter is not baryonic at all, but that it is made up of other, more exotic particles like axions or WIMPS (Weakly Interacting Massive Particles).

 

Differences between dark matter and energy

Dark matter

–         Dark matter works like an attractive force. It holds our universe together. It cannot be seen because dark matter does interact with gravity, but it doesn’t reflect, absorb, or emit light

–         Dark matter makes up 27 percent.

 

Dark energy

–         Meanwhile, dark energy is a repulsive force — a sort of anti-gravity — that drives the universe’s ever-accelerating expansion.

–         Dark energy is the far more dominant force of the two making 68%.

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