Dark Matter, Dark Energy, and the Expansion of the Universe By Michael Howard

Is the Universe Static Einstein’s General Theory of Relativity predicts that the Universe must not be static, but Einstein refused to believe it Edwin Hubble began studying the distances of galaxies and compared them to the speed at which they were moving away from Earth. Then he compared it to the work of a man who had been making similar observations years earlier. He found that the galaxies that were farther away were moving at a higher speed.

The Expansion of the Universe Hubble decided that since the Earth must not be the center of the universe, this must be true for any galaxy, not just our own. This is what led Hubble to the conclusion that the universe is expanding.

Einstein’s Biggest Blunder Had Einstein not created the cosmological constant he most likely would have discovered the expansion of the universe before Hubble.

The Big Crunch The Big Bang gives the universe the force to continue to expand, but it would stand to reason that gravity would eventually slow this force down. When gravity begins to overpower this force the universe would begin to contract

The Expansion/Contraction of the Universe Bottom to Top- The Big Bang Top to Bottom- The Big Crunch

The Problem with the Big Crunch 1998 Announcement that not only was the Universe expanding, but it was doing it at an accelerating rate

The 2011 Nobel Prize in Physics From Left to Right- Saul Perlmutter, Brian Schmidt and Adam Riess

Type Ia Supernovae It was discovered that these supernovae had a smaller redshift than would be expected. Because these telescopes are looking back in time the fact that the redshift was smaller than expected means that they were moving slower in the past.

Why is the Universe Accelerating? We don’t know One would expect the force the caused the expansion to eventually be overpowered by gravity Because this is not the case something must be overpowering the force of gravity or the general theory of relativity has a major flaw.

So if the explanation is that there is a force that is overpowering gravity then that would mean that Einstein was correct in adding the cosmological constant

The Cosmological Constant Maybe Einstein wasn’t wrong

Dark Energy Quantum Vacuum Energy- particles which are constantly coming in and out of existence generate energy The problem is that the calculation of this energy is a problem in quantum mechanics and the expansion of the universe is in terms of general relativity Accounts for about 70% of the universe.

Dark Matter Can not absorb or emit light Thought to exist because of its effect on gravity If there was no dark matter the galaxies would fly apart Could be MACHOs or WIMPs

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