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Dark Energy


Dark energy is theoretical form of energy that exists in all outer space. Although it is all theoretical research it is believe to be accelerating the expansion of the universe. This means that dark energy has a negative gravitational pull that is push matter away. Dark energy makes up approximately 73% of the mass/energy in the universe. There are two forms of dark energy, cosmological constant and scalar fields.

Albert Einstein, one of the most well known physicist, was one of the first to discover dark energy or as it was known back then the cosmological constant. He created one of the essential parts to physics, the general theory of relativity. To simplify it, it states that mass of object affects the shape of space and the flow of time. Due to this warp of space-time gravity is created. When he first created this theory he did not take into account that the universe was expanding. He created a hypothetical variable of negative gravitational force called the cosmological constant or what is known now as dark energy.

Scientists have been noticing the expansion of the universe was increasing. This unexplained observation confused scientists. Ever since the big bang the universe was expanding at a slower rate. During the big bang the universe exploded and expanded at an alarming rate. The universe cooled and planets and solar systems were formed. Theoretically the universe should not be accelerating and expanding at the rate close of the big bang. After observing supernovae, scientists were astonished to see that the star was farther away that anticipated. Some unknown form of energy is accelerating the expansion of the universe and resisting the gravity pull of the galaxies. This energy is called dark energy.

Another way scientists are observing the effects of dark energy is something call the redshift. The sky is filled with galaxies that emit light. Light travels at the speed of light away from the source. When it reaches telescopes the galaxies look blue. As the light and color is traveling through space it is actually traveling space that is expanding. The light waves are stretched out through the expanding space. This effect makes the color of the light that we see red. Red light waves are farther apart and wider than blue light waves. This phenomenon is part of the Doppler effect. Scientists have used this information to conclude the presence of dark matter that is expanding the universe.

Another explanation of of dark energy is energy that is given off when particles flash into existence. Scientists have theorized that energy and matter can be created from nothingness. This contradicts the law of conservation of energy, that states energy can be created nor destroyed. The creation and alienation of matter gives of small amount of energy that is given the named dark energy.

Another way dark energy is contradicting the law of conservation of energy is that as the space is expanding it is being filled with dark energy that is created. This process is expanding the universe even faster and its filling space with even more dark energy.

In far away galaxies the universe is thought to be expanding faster than the speed of light. In this case the light emitted by the galaxies will never reach us, as the light has to go through an expanding universe that is expanding faster than the light can travel. The light will hypothetically never move. If the universe were to be expanding at the speed of light, galaxies would just disappear from our view. Once the space in between the galaxy and us reaches the speed of light, that last bit of light that managed to move before the expansion of the universe reached light speed would be the last light of the galaxy. This would mean that after this time the galaxy would just disappear from our view. For the universe to be expanding at the speed of light a very powerful force must be acting upon it; dark energy.



Pie Chart - 74% Dark Energy, 22% Dark Matter, 4% Visible Matter
Pie Chart - 74% Dark Energy, 22% Dark Matter, 4% Visible Matter

This pie chart represents the percent of
the universe that is made of dark energy, dark matter, and visible matter.