Schjelderup 1 Ari Schjelderup David Schaffer PHYS-1040-009 10/30/11 The Big Bang Theory When I was a little girl I asked my mom how long God had been around. She told me he had been around forever. When I didn t understand, she told me it was something you can only understand after you die. I asked her if the universe was the same way, if it had been around forever. She told me she didn t know. Has it been around forever? Did the universe form over a long time, or did it just appear at some point? If it formed, there would have to have been something there in the first place, but then, that would have been the universe, right? It wouldn t make sense to have a start to the universe, because stuff can t just appear out of nowhere! I used to get into deep thought about it. My mind would just go in circles, and I would have to stop thinking about it out of irritation. At this time I was still very young, around seven years old, so I never researched it. I just thought about it. So, Now that I m older, what s the answer? Is there one? Did the universe just appear out of nowhere? How long ago did it happen? And how in the world would we know? Let s say there was a nothing. No gases, atoms, no space, and not even time. Then, maybe instantaneously, a little dense thing smaller than an atom, filled with light, appeared. According to a book called Astronomy for dummies, this was the very small universe. The book also explains that space expanded during the first trillionth of a trillionth of a trillionth second, and the universe grew more than a trillionth of a trillionth of a trillionth time bigger. It is hard to believe, very hard to believe, that the stars, galaxies, and our home planet, that we see today
Schjelderup 2 began in a very condensed piece of energy that was very small. But this is all hypothetical right? No one could have proof about something that happened 13.7 billion years ago! or could they? What I just explained is what scientist believe happened to form the universe, and it is called the Big Bang Theory. Well, first, it s true that it can t be proven. Almost any science book I ve read tells me that nothing can be proven. For example my physics book Conceptual Physics by Paul Hewitt explains how only things that can be disproven are science, and how nothing can be proven. That s why things you hear the term theory so much. However, it is a level of evidence that can answer our question. The first piece of evidence is that the universe is expanding. Edwin Hubble, from whom the Hubble Telescope was named, showed, using the doppler effect, that galaxies are flying apart due to the expansion of space itself. So, if galaxies are moving apart, they were probably once closer. The next piece of evidence was the realization that the Big Bang would make intense radiation. Twenty years after this idea was formed, Arno Penzias and Robert Wilson detected a faint crackling with their radio receiver while they were scanning the sky. At first it was thought to be static, but it turned out to be the radiation left over from the Big Bang. If it had cooled steadily since the Big Bang, the amount that is there would be correct. The third piece of strong evidence has to do with helium. All the baryonic matter in the universe is 24% helium. The book The Essential Cosmic Perspective says that the helium couldn t have come from the nuclear reactions inside stars because it hasn t been going on long enough to have made this much. But it is the right amount that would have been made in the Big Bang.
Schjelderup 3 Lastly, Astronomy for Dummies shows the laps piece of indication to the Big Band theory. If the universe was infinite, and everyplace the same, there would be stars all over the sky, and it would be light, even at night. Even dust would not change because the dust would be heated so much over a long period of time that it would become just as hot as the stars. Either the universe has a limited amount of stars, or the universe changes. Yet, some don t believe that the Big Bang happened. Eric Lerner, Author of The Big Bang Never Happened, for instance, believes that there are several things wrong with the evidence for the big bang. Lerner points out that if the Big Bang really did happen, there shouldn t be anything older than 13.7 billion year old, which is said to be when the Big Bang happened. But there is a large-scale void that couldn t have been formed in the time since the big bang happened because it must have taken at least 70 billion years to be formed. This means that either the Big Bang Theory is wrong, the prediction on how long ago it happened is wrong, or the prediction that the void had to form in 70 billion years, is wrong. For the Big Bang Theory to be true, there must be much more dark matter than plain matter, but white dwarfs and warm plasma clouds that were discovered show that there is enough ordinary matter to report for gravitational effects observed, which means that there is no room for more dark matter. Maybe the Big Bang Theory has some flaws, or maybe it s even more complicated than it already seems. The idea began a couple of decades ago, and there is still research going on, and the Big Bang Theory will never be proven to be correct. Also, this is the most successful explanation for how the universe began, and it explains so many things.
Schjelderup 4 Einstein found out that the general law of relativity predicted that the universe could not be sitting still because if it were, everything would collapse due to gravity. At the time, Einstein thought the universe was static so he came up with the idea of the cosmological constant. The cosmological constant acted like a balance, a counteraction with the force of gravity. The reason he did this was because he insisted that the universe stood still. If he hadn t been so sure of himself, maybe he would have come up with the right answer; that the universe is still expanding. After Hubble discovered this, Einstein called his idea the greatest blunder of his career. Recently, however, some stars have been found that appear to be older than the universe is supposed to be. the way this could happen is if the universe is expanding faster than it was before. The way this could be true is if the cosmological constant wasn t a blunder after all. If it [Einstein s equations of general relativity] is not zero, then it represents a repulsive force or a type of energy (sometimes called dark energy or quintessence that might cause the expansion of the universe to accelerate with time. (Steven Weinberg, in Einstein s Mistakes ). In other words: when the equations of general relativity is not zero, then it might represents a type of energy that might cause the expansion of the universe to accelerate with time. My satisfaction for knowing the answer to the universe has never faded from when I was a little girl, but when I first heard about the big bang I got a little more interested. I m still just human, and I can t comprehend something so huge, but it is fun to hear about how the universe might have been created. It still doesn t make sense to me how many of these things occur, and where the smaller-than-atom universe came from (the one before the big bang happened), but
Schjelderup 5 there is still time. Being able to learn about a reasonable theory on how the universe was created is good enough for me right now. After all, the universe is a big place, and learning about how it might have been created, is amazing. Work Cited: Lerner, Eric. The big bang never happened. New York: Vintage Books, 1992. Hewitt, Paul. Conceptual Physics + Masteringphysics. City: Addison-Wesley, 2011. Bennett, Jeffrey. Donahue, Megan. Schneider, Nicholas. And Voit, Mark. The essential cosmic perspective. San Francisco: Addison-Wesley, 2009. Maran, Stephen. Astronomy for dummies. Hoboken, NJ: Wiley, 2005 Weinberg, Steven. Einstein s Mistakes Physics Today 58.11 (2005_: 31-35. Academic Search Premier. Web. 17 Nov. 2011