Wednesday, February 27, 2013

The big bang


Amelia Taylor
2/27/13
The Big Bang
Has the universe been around forever? Evidence has strongly suggested no. Observations like cosmic background radiation and cosmic inflation have caused scientists to formulate the big bang theory. The big bang theory is probably the most mysterious and intriguing theory that physics has pointed in the direction of. It regards the birth of the universe, where everything came from. The “beginning of time”.
The big bang theory states that 13.7 billion years ago, the universe started from a point that had zero volume called a singularity. At this point it was infinitely hot and it possessed an infinite amount of energy, and then it “banged”. After one millionth of a second, all matter was created. It was evenly spread throughout the new universe. Then, certain areas became denser, possibly due to fluctuations in the quantum field. They pulled in more matter due to the pull of gravity. The first atomic nuclei formed 3 minutes after the bang, and after 400 million years, the first galaxies.
There is actually not enough detectable matter in the universe to influence gravity to make matter clump together to form today’s universe in the time period of 13.7 billion years. The missing matter is called “dark matter”. It’s invisible because it doesn’t show up when light hits hit like ordinary matter does. There’s 7 times as much dark matter in the universe as there is normal matter. We know it’s there because it’s gravitational pull bends the light path of stars.
There is incredible evidence for the big bang called cosmic background radiation. When the big bang banged, it was very bright and hot. That light is forever in our universe, and has since cooled to 2.7 degrees above absolute zero, making it the coldest thing in our universe. It’s no longer visible and is detected as microwaves. The cosmic background radiation that we first detected in 1965 was from the very beginning of the universe when matter was smooth. Because matter was smooth, the light around it was smooth and so we detected it as smooth. Then, in the early 90’s we detected fluctuations in the cosmic background radiation. This was the light traveling to us from when matter first started to fluctuate and clump together.
Another strong point supporting the big bang theory is that the universe is constantly getting bigger. The whole universe has been expanding ever since it first banged. We know this because every star and planet and galaxy in the universe is being pushed away from each other at a gradually speeding rate. No matter what point in space you are, everything around you is moving away from you. The universe is “inflating”. If it’s always getting bigger, then we come to the conclusion that it must have been smaller in the past. If we view the universe in rewind we would see it getting smaller and smaller until it collapsed into a singularity.
The universe is expanding faster than it has the energy to do so. The universe requires a certain amount of mass to counteract gravity in order to not be overcomed by it. This needed amount is called critical mass. All of the physical matter and dark matter in the universe only adds to ⅓ of the critical mass. The missing energy is called “dark energy”. It is very mysterious and fills all of “empty” space between the stars and planets and galaxies, the “dark stuff” in the sky. Because all energy has an effective mass, the dark energy ends up accounting for ⅔ of the critical mass. Everything pieces together, but it is still all a secret we are working to unveil.
When the universe banged into existence, it expanded very fast like an explosion. Then it cooled and the expansion slowed down, and has since been moving at the more slightly steady rate we see today. Because the universe is getting bigger, there is talk of it one day officially running out of steam. It would stop expanding, it would come to a halt and freeze.
This is just one of the ideas regarding the fate of the universe. A similar one called the big chill states that the universe would go on expanding forever even as everything in it dies out and becomes extinct. Another theory called the big crunch states that gravity will eventually overcome all other forces, causing cosmic inflation to reverse, collapsing the universe to a singularity. The last theory is called the big rip and states that dark energy will overcome gravity, causing the universe to dramatically expand, or tear apart.
Every part of our universe all came from a single point. You and everything around you came from a single point that expanded and is still technically one being. We are all connected. Everything is “entangled”. We were all born together in the big bang. Our consciousness, too, is one being. Consciousness is part of our universe, which means it came into existence with everything else in the big bang. Therefore we all share it. We are the part of the universe that “thinks”, we are the awareness of the universe. We get a chance to be fascinated by it and observe the world around us. Our “thoughts” take no physical form but they’re obviously there. We don’t share separate consciousnesses, we share the one that banged into existence with everything else. Nothing in the universe is separate. It’s all one thing that exploded into being and has been cooling, expanding and evolving ever since.
We have no idea what banged, how it banged, where it banged or what was before it banged. All we know is that it banged. We call it the universe and we’re living in it and it’s beautiful. We live in a wonderland of ever unraveling mysteries that will fascinate and shock us if we choose to explore. Our universe truly is a magnificent, complex and amazing place.

No comments:

Post a Comment