Big Bang Theory example essay topic
A later hypothesis was created to replace the common belief that the universe was completely static. The expansion of the universe was discovered in 1929 when Edwin Hubble discovered that every galaxy in the universe was moving away from each other, this meant that the universe was expanding. Hubble found the movement of the galaxies by using a phenomenon known as the Doppler effect. This effect caused bodies moving away from an observer to have a "red-shifted" spectrum (the light spectrum of the body had been shifted closer to red) and bodies moving towards an observer to be "blue-shifted" The expansion was traced backwards through time to discover that all the galaxies were created from the same point. It was later believed that all matter spawn from that "center of the universe" discovered by Hubble. Matter would collec outside this singularity and form every moon, planet, and star known today.
The Steady State Theory was very attractive because it featured a universe with no beginning or end. The theory meant that scientist had to abandon the laws of conservation of mass and energy. It seemed convincing that the laws of physics could breakdown at a certain point but more and more evidence gathered against the Steady State Theory, leading to many modifications to it. Until finally the theory was dropped completely with the discovery of the smooth microwave background radiation (radiation so ancient it had shifted right out of the visible spectrum into microwave radiation). A smooth background to the universe suggested that it was hot and uniform - the ideal conditions for the Big Bang. The Big Bang was almost exactly what it sounds like - a giant explosion.
During this explosion all the materials in the universe today (matter, energy and even time) were expelled into a vacuum about 12 billion years ago. The combined mass of the universe was interpolated to a point of zero volume (therefore infinite density). It is impossible to guess what the universe would physically be like because the density of the universe cannot be plugged into any physical equation. The history of the universe can be traced back to a moment 10- 33 seconds after the big bang. At this moment the universe is filled with a sea of various exotic particles along with electrons, photons, and neutrinos (and their respectable anti-particles). At this time there are also a small number of protons and neutrons.
The protons and neutrons are participating in sub-atomic reactions. The two most important of these reactions are: Antineutrino + Proton -- Positron (anti-electron) + Neutron Neutrino + Neutron -- Electron + Proton In effect the protons are becoming neutrons and vice-versa. The energies are so great that simple atoms being formed fall apart immediately after coming together. As the universe expands, and loses energy the electrons and positrons begin to collide, effectively annihilating one another, leaving only energy in the form of photons and neutrinos. Appropriately fourteen seconds after the Big Bang simple atoms are formed like deuterium and helium. About three minutes after the incidence of creation, the universe has sufficiently cooled to allow formations of helium and other light elements.
As it is proven by the cosmic background radiation, the universe was uniformly smooth. A change had to have occurred, otherwise no celestial objects would have formed and as the particles lost energy, they would simply decompose into simpler particles. Something had to have caused the particles to group together and form larger entities. Gravity comes to mind, but, at this point the largest particle is a helium atom, which due to it's small size, has very little of a gravitational pull.
The only respectable theory is the "cosmic string theory" is states that our four dimensional space (three spatial dimensions plus time) is made up of knots in seven or eight dimensional 'strings'. These strings are really massive (each meter of string would weigh 1021 kg). This would require that the universe was not a complete vacuum prior to the Big Bang because space itself would be make up of cosmic strings. The cosmic strings while being extremely heavy are also very tight, so tight that if a string were not either a circle (connect to itself in a loop) or of infinite length, it would pull itself together into nothing. A string can also disconnect and reattach with other strings that are intersecting it.
Now a universe can be pictured with an infinite number of 'cosmic strings' interacting with each other even before the Big Bang. After the material was dispersed via the Big Bang, particles were attracted to the cosmic strings (mainly loops, since the mass would be more centralized). These cosmic string loops, could be the basis for the formation of a galaxy. The small particles would be attracted by the strong gravitational field of the loops, thus creating a hub for the creation of a galaxy. After some years all the loops would decay because of their strong emission of gravitational radiation leaving enough collected matter to form a fully functioning galaxy behind. In clouds of dust and gas (mainly hydrogen) at the center of the galaxy, pressure and temperature build causing an increase in density and gravity.
The heavier particles fall to an orbital cloud of the young star while the lighter elements close in on the core. This increase in gravity causes a further increase in pressure, until the center of the star has the conditions ideal for nuclear fusion. This process occurs at the very core of the star and converts hydrogen into helium at an alarming rate. A star is born. The outer cloud of the star may also harbor some heavenly bodies usually planets or other stars.
The clouds of dust collect the same way in planet except the temperatures don't quite reach the point where nuclear reactions take place. By means of commonly accepted theories, the origin of the universe from the Big Bang to the formation of a planet, has been successfully detailed. Thanks to new technology introduced in the past fifty years and thank to intellectual minds capable of supporting that technology, more has been learned about our would than ever imagined possible. Although all the advances assumed feasible have put to use will still are far from knowing the absolute truth.
Surely the early astronomers thought that they were correct in their theories, but most ended up being dead wrong. We cannot assume that all of our current theories are correct because although we may know more, we will never know all. Hawking, S.W. (1988). A Brief History Of Time. New York: Bantam. Kitchen, C.R. (1990).
Journeys To The End Of The Universe. Bristol: Adam Holger. Silk, Joseph. (1994).
A Short History Of The Universe. New York: Scientific American Library. Wien berg, Steven. (1977). The First Three Minutes.
New York: Basic Books, Inc.