Universe Before The Big Bang example essay topic

The Big Bang theory states that all the matter that is in the universe was once in a very small amount of space with infinite temperature, pressure, and density. This theory is well supported and there are many reason for it's support. One main reason is that no one really has a clue and The Big Bang Theory seems far fetched but more reasonable than any other ideas that there are out there. Some of the important thing to know about the big bang to understand are the beginning and the few seconds immediately after the actually bang.

Also what generally has happened since the then. It is important to know theories of how it will end as well, and to get a well rounded opinion, I feel it useful to have some of the other possibilities outlined. The best place to start is the beginning. One of the things that cosmologists are not yet sure about is the Big Bang itself. It is not yet possible to give a definitive answer to the questions: what was the Big Bang and why did it happen?

However, there has been a great deal of speculation recently on this subject, and it may not be long before a definitive, or almost definitive, answer will be declared. For the moment we will simply take the Big Bang as it is given, a huge explosion in which time and space began expanding. It is important to realize that space itself originated in the Big Bang. IT is tempting to think of the universe before the Big Bang as being a vast, infinite, expanse of empty space, like the space between the galaxy clusters today. The Big Bang, then, would have flung matter into this nothingness, but this is not what happened. Space itself was created during the Big Bang.

Einstein and all subsequent cosmologists have viewed space as being as real as matter. In fact, physicists now view empty space as a sea of "virtual particles". So space is now expanding along with the galaxies and stars that exist with it and has been expanding ever since the Big Bang. Actually, cosmologists actually have a clearer picture of what the universe was like during the period right after the Big Bang than they are about the universe today. The reason for this is universe was very simple, in comparison, then. The universe was filled with a hot soup of particles like a hot gas trapped in a box.

The photons in the cosmic microwave background radiation are the last remnant of that hot soup. Everything else has evolved into more complex forms like planets, stars, and galaxies. From this background radiation, cosmologists have been able to learn things about the particles that filled the universe 18 billion years ago (the approximate time of the Big Bang). Perhaps the single most important thing that we know about conditions immediately after the Big Bang is that the universe was extremely dense. That is, all the matter and energy in it was compressed very tightly together. On the other hand we do not know how big the universe was immediately after the Big Bang.

Because we do not know how big the universe is now. If the Universe is infinitely large then it would have been infinitely large then, because there is now way something could go from have a finite size to having an infinite size. So if the universe has a finite size today then it had a finite, and proportionally small, size then. We do, however, know how large the visible universe would have been immediately after the Big Bang.

The visible universe is the portion of the universe that an observer, imaginary for comparison, would be able to see. The visible universe today has a radius of about 18 billion light years, because that is how far light has been able to travel in the approximately 18 billion years since the Big Bang. Anything outside of that 18 billion light year radius would be invisible to us because the light from it has not reached us yet. This would be true for observers anywhere in the universe, not just earth. Observer more than 18 billion years from earth would not be able to see us either, no matter how good there telescopes where. Surprisingly, it is possible for the actual size of the universe to increase faster than the size of the visible universe.

This is surprising because it means that the universe might be expanding faster than the speed of light. Einstein's Special Theory of Relativity states quite firmly that nothing can move faster than the speed of light. Einstein, however, was talking about the motion of matter and radiation through space. The expansion of the universe is not movement through space, but the expansion of space itself. Einstein's theory does not forbid space from expanding faster than the speed of light. Things happened very quickly right after the Big Bang.

Compared to the speed of events in the seconds and minutes after the creation of the universe, the modern universe moves something a great deal slower than a snail. So, it is common for physicists to divide the seconds and even fractions of seconds after the Big Bang into eras. Although in may seem odd to speak of an interval of time shorter than a seconds as and era, it makes sense in terms of rapid space events. The earliest era of which physicists can speak with any confidence at all is the grand unification era. The era during which the strong and weak forces were still united in a sing super force. This era lasted from 10 to the -43 all the way to 10 to the -35 seconds after the Big Bang.

The next era was called the electro weak era. We are most sure about the way things were in the electro weak era, because we can actually duplicate the conditions of the electro weak era in particle accelerators. As temperature continued to drop the electro weak force froze out into the electromagnetic and weak forces, and things began to charge into particles much like those found in the universe today. At about 10 to the -6 seconds after the Big Bang, the universe entered the Hadron era. Because temperatures were now lower and kinetic energy of particles smaller things were able to bind together to form larger particles that we call hadrons (protons and neutrons). This process is called hadron ization.

The tremendous energies present in the universe at this time, temperatures of just under one million billion degrees Kelvin, caused brand-new hadrons to be created in vast numbers out of the virtual particles of the vacuum, just as particles are created in cosmic-ray showers today but on a much larger scale. When the hadron era ended and event that took place about 10 to the -3 seconds after the Big Bang a violent change came over the universe. the temperature in the universe ceased to be high enough to create new hadrons out of the vacuum so that new hadrons were no longer replacing the one that were turned into gamma rays. The next era in the lepton era. Just as hadrons were created out of the vacuum during the hadron era, so leptons, such as electrons were created out of the vacuum during the lepton era. this is possible because leptons, having less mass than hadrons, required less energy to create. the temperature in the lepton era is about one trillion degrees Kelvin. The universe is still so dense that just the particles in an area of the universe one centimeter on all sides would have weighed a thousand tons.

The visible universe was still less than one light-second in radius. After the end of the lepton era matter in the universe had been reduced to one one-billionth what it had been a fraction of a second earlier, and the universe was dominated by the photon. The next era is the photon era. In fact we might still live in the photon era today were it not that the photons gradually lost the energy that they posed shortly after the Big Bang. At that time most of the energy was in the form of photons, today most of the energy is in the form of matter so we live in the matter era. You might notice that no mention has been made so far of atoms in the early universe. the reason for this is that there were no atoms in the early universe.

It was much too hot for electrons to remain in orbit around protons. In fact for most of the period I mentioned it was too hot for neutrons and protons to bind together to form the nucleus. Even if, for the tiniest instant, an atom like configuration of particles had formed, it would have been broken apart by the fiercely energetic activity of the extremely hot universe. of course, protons can be viewed as the nuclei of hydrogen atoms, since the nucleus of a hydrogen atom consist of a single proton. In that sense, hydrogen nuclei came into existence during the hadron era, but full fledged hydrogen atoms did not form then and would not form for some time to come. At a little less than four seconds after the Big Bang, things had cooled off enough for the nuclei of the next larger atom, helium, to form. Shortly after however, the universe became too cool for nuclei synthesis, the creation of atomic nuclei from protons and neutrons.

At that point, the basic elements of the universe had pretty much finished forming. Roughly 70 percent of hydrogen nuclei and 30 percent in the form of helium nuclei, which are pretty much the proportions of these elements in the universe today. Even after these nuclei had formed it was still much too hot for atoms to form around them. In fact, it remained to hot for atoms to form for the next 700,000 years. A very long time compared to the eras we have been talking about. You may be surprised to learn that during this entire period the entire universe was opaque.

The reason is that, because atoms had not yet formed, the universe was filled with free electrons. Electrons tend to absorb photons, the particles of light. A photon could not travel very far though this early universe without being absorbed by and electron. Of course, for every photon absorbed by and electron, another photon would have been released by and electron. Thus the universe would have glowed brightly but would have been dense as a super thick fog. any observer in the middle of the early universe would have been unable to see a hand held in front of his face. Then 700,000 after the Big Bang, universe cooled to the point where electrons, could become bound to nuclei and form atoms.

To our imaginary observer, it would have been as though the fog had lifted. The universe would have become transparent. Normal matter had come into existence. The universe was a giant nebula of hydrogen and helium gases. Because the atoms in the early universe were entirely those of hydrogen and helium, you might wonder where heavier elements came from, such as carbon and oxygen atoms that are so vital to living things. The answer is that many of them were formed much later, in the hearts of stars.

But the majority of elements, that can't be created in stars, are created in super nova explosions. One of the ends to the universe may be a closed universe. If the universe is closed, then it will eventually stop expanding and. How long will it take before this re collapse occurs? That depends on how much matter is in the universe.

A few theorists have gone as far to give specific figures for the end of expansion, some as little as 28 billion years. Figures in the trillions of years have also been cited. Once the expansion stops, the collapse will go on for as long as the expansion did. Astronomers in this far-off future universe will first notice that the distant galaxies are no longer re-shifted, then that they have actually become blue-shifted. The matter in the universe will start becoming denser. IF the universe has a finite size, it will start to grow smaller and in turn hotter. this increase in heat will be insignificant to all except radio astronomers for some billions of years. as the universe becomes extremely small this heat will become noticeable even to those not attuned to the activities of photons in space.

As seen from the surface of earth the sky will actually start to glow. By this time a number of other significant changes will have taken place in the universe. The space between the galaxies will have been squeezed out of existence, and galaxies will merge. The universe will be a vast sea of stars without any larger structures like the astronomers before the mid 1920's envisioned the universe today. The universe will then enter a phase that cosmologists like to call the Big Crunch, the Big Bang in reverse. The universe will collapse into a state of infinite density.

One possibility is that the universe may explode once again in another Big Bang. A brand new might be created, which may be very much like the universe in which we live today, or completely different. That universe would the collapse in another Big Crunch, which would then lead to another Big Bang, and so forth. Potentially, this process could go on forever and may have been going on forever in the past. we may not have been the first universe that has existed and we may not be the last. The universe may also be open or flat. If is flat there will be no Big Crunch.

The universe will never collapse. It will exist forever. Interestingly, the equations of the inflationary universe hypothesis stat the universe must be flat. This is the only possible result of cosmic inflation, which explains why the observed matter density of the universe is so close to that required to make it flat.

If inflation is correct, there never will be a Big Crunch. But neither will the universe remain forever in its current state. Eventually, Even the stars must burn out. And, if the current grand unification theories are correct, even matter itself will fall apart sooner of later. What will the future of an open universe be like?

As far as we know, the universe will remain pretty much as it is now for a very long time. Our sun will burn out in about 15 billion years, but other stars much like it will be born from clouds of gas and dust to takes its place. But there is only so much energy available in the universe for the building of new stars. Just as the law of thermodynamics tell us that a closed universe can't go on forever, so they tell us that new stars cannot go on being created forever in an open universe. Eventually the last star will die out and will not be replace.

The proton will eventually decay. After about a billion billion billion billion years, all atoms will fall apart, and matter as we know it will cease to exist. The universe will be a vast sea of leptons and messenger particles. One main, but unsupported, theory is that the universe was created by God. This theory is not excepted in the scientific community because in has no evidence to back it up.

That doesn't mean it isn't a possibility. There are a few other theories of the creations of the universe, but no other theories are as excepted as the big bang theory. Some of the important stuff to know that I have covered is the eras right after the Big Bang, the Big Bang it self and a few of the possible endings to the universe. I hope with this information you can have a better understanding of the universe, its creation, and it's endings.