what is big bang theory  ?
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The Big Bang Theory is the dominant scientific theory about the origin of the universe. According to the big bang, the universe was created sometime between 10 billion and 20 billion years ago from a cosmic explosion that hurled matter and in all directions. \nIn 1927, the Belgian priest Georges Lemaître was the first to propose that the universe began with the explosion of a primeval atom. His proposal came after observing the red shift in distant nebulas by astronomers to a model of the universe based on relativity. Years later, Edwin Hubble found experimental evidence to help justify Lemaître's theory. He found that distant galaxies in every direction are going away from us with speeds proportional to their distance. \n\nThe big bang was initially suggested because it explains why distant galaxies are traveling away from us at great speeds. The theory also predicts the existence of cosmic background radiation (the glow left over from the explosion itself). The Big Bang Theory received its strongest confirmation when this radiation was discovered in 1964 by Arno Penzias and Robert Wilson, who later won the Nobel Prize for this discovery. \n\nAlthough the Big Bang Theory is widely accepted, it probably will never be proved; consequentially, leaving a number of tough, unanswered questions.
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your answer is in \nhttp://en.wikipedia.org/wiki/Big_Bang
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Cheerleader101,\n    Let us go on a bit on the scientific track.  Have you heard about the famous 'Big Bang Theory'?  It says that the Universe was in the beginning a condensed mass which shrank and shrank inwards.  When it could now shrink any more becoming a condensed mass of great pressure, it burst and thus ever expanding Universe was created. This explosion of immeasurable magnitude is called by the scietists who formulated this theory as Big Bang.  \n    Let us now go on the track of Ancient Vedic Wisdom propagated by the Rishis(Indian Saints) of india.  About 4000BC, in the Upanishads, Rishis wrote:  "Asade Vedamagra. Thad Aseeth. Thadandam Niravarthathaya. Thad Visphotayatha. Rajatham cha Suvarnam Abhavath." This is Sanskrit which means :In the Beginning there was mothing.  From nothing existence was born.  And it became a round mass and it began to shrink.  Then when it could not shrink anymore, it exploded" .  This is the simple and plain meaning.  Great amount of explanations and details lie behind these utterances of Rishis.\n    I will write about this in detail later!\n         Mukundan Pallipravan
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The Big Crunch is the opposite of the Big Bang. It can only happen if things don't increasingly accelerate away from eachother as is the current theory. When all the galaxies and matter pulls together to a singular point you have Big Crunch.
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Physical cosmology is the branch of physics and astrophysics that deals with the study of the physical origins of the Universe (the Cosmos) and the nature of the Universe on its very largest scales.
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Well you can never be sure, but one theory is "The Big Bang".  Some useful websites are: \n\n- liftoff.msfc.nasa.gov/academy/universe/b_bang.html\n- www.umich.edu/~gs265/bigbang.htm\n- en.wikipedia.org/wiki/Big_Bang \n\nHave fun!
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Everything we know about, everything we can see, behaves as if 13.7 billion years ago it was a dense, hot plasma that has been expanding and cooling ever since.  That's the Big Bang theory, and there is a tremendous amount of overlapping, detailed evidence to show that it's correct.  The Big Bang theory being wrong is about as likely, and makes about as much sense, as the idea that a Sun-centered solar system is wrong.  Essentially all of modern astronomy depends on the Big Bang to make sense.  The main observations are:\n\n1) The redshift of more distant galaxies is larger than that of nearby galaxies.\n\n2) Quasars and radio sources are seen to evolve.  There were many quasars in the past, now there are almost none.\n\n3) The amounts of the light elements Deuterium and Hydrogen make sense in the context of neucleosynthesis in the Big Bang.\n\n4) The Cosmic Microwave Backround Radiation is as predicted by the Big Bang theory, both in magnitude and in the details of its anisotropy in amplitude and polarization.\n\n5) All stars and galaxies evolve as if that evolution were set into motion by the Big Bang.\n\n\nYour notion of mirages and crests makes no sense in the context of modern physics.  We do see some warpage of space, particularly gravitational lensing by clusters of galaxies, but the Cosmic Microwave Background is most certainly only 400,000 lightyears from our event horizon.\n\nMany current versions of the Big Bang involve a Universe that exists eternally in both the past and future.  Our Big Bang was not necessarily the beginning of the Universe.
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Because the universe is a vacuum and there's nothing to stop it from expanding. This is assuming that the big bang theory is correct and it's expanding because of the explosion .
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Big Bang is a theory that tries to explain the formation of the universe, its galaxies, its stars and planets etc.\n\nIt says that the Universe was created by an explosion of a Primeval Atom thus causing it to expand and move away from each other. This was actually based on the Hubble Law which says that Galaxies around us are expanding at speeds directly proportional to their distance from Earth, based on the observation of Edwin Hubble, 1929.\n\nIts a huge topic with lots of technical arguments and counter arguments. Here is the link that will satisfy your quest on Big Bang, atleast for starters...\n\n.:Fishie:.
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If I were you, I'd search it myself instead of asking people, but that's just me.\n\nThere are so many theories to how the universe started, in which the Big Bang theory is the most popular. In this theory, it all started with a single point with the same amount of matter in the universe and it was really really hot. Then it just explodes, continuing to expand at an alarming speed. It was so hot that not even the particles that made up atoms could not even form until the universe was expanded enough to cool down, and then the first atoms were made. Then it just continues to expand to where we are now.\n\nThat's one theory. I like the never-started theory. There was no beginning to our universe. The reason why the Big Bang theory is the most accepted theory is because we (us humans) like to think that there is a start to everything. It just makes sense that there is a beginning. And it's easier to build theories and ideas upon it.\n\nPS Penguins!!!
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Big Bang is the only acceptable theory for now.\nSteady State isn't really accepted anymore.\n\nBig Crunch is a variation of the Big Bang theory that is becoming less and less accepted.\n\nFrom what we've gathered there's not enough matter in the universe to bring it back together (the Big Crunch) so therefore it will keep expanding forever.
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Steady state theory has no answers for two major astronomical observations.\n\n1. Cosmic microwave background radiation (CMB)\n2. Hubble expansion.\n\nAs a result the theory has been discarded by the majority of professional astronomers.  The Big Bang theory does provide answers for those two bits of observation.  It may not be perfect but it is the best we got.  That's what theories are...the best explanation until something better comes along.
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I think you are confused a bit. If you look around at nature, it is incredibly complex. The more we study it and the more we analyze i and measure it, the more complicated it appears. \n\nThe scientific theories and laws are attempts to put some order into this mass of complicated observations, to try to explain what is happening. Predictions based on these scientific theories can be made, and if it is a good theory, then the prediction will be verified by data. \n\nThe big bang is just one theory for the origin of the universe that attempts to explain what we observe: hubble's law, the microwave background radiation, etc. It is an attempt to produce a simpler theory to explain a very complicated and confusing set of observations.
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bangie matter..bangie stuff..bang matter..prebloom..big bing..small bang..barney..pebble?..orange seed..bang seed..THE DOT..squished universe:P..nano²-existence or smth..\ni'll keep thinking about it its kinda fun:P\n..and maybe i'll come back
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big bang. and its a big universe, we cant be all alone
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This is probably the best explanation I can give you:\n\nThe big bang theory basicaly states that at one point, there was a huge ammount of energy that clashed with itself into a given point. Through various experiments, it has been proven that clashing highly mobile sources of energetic particles can result in genesis, in the formation of matter and anti matter. This means that this energy was transformed into matter (matter is basicaly just energy trapped into the form of an atom, giving curvature to the universe, and therefore having mass). The matter, as we know it today, shot towards 1 direction from the bang, and the anti matter into the other. Theoreticaly there should be the same ammount of matter as there is antimatter in the universe. There are galaxies just like ours out there made up of antimatter, and would look virtualy the same. If these galaxies were to come together, they would turn back into the energy, since the reaction of 1 atom of hydrogen, and 1 antihydrogen atom result in the release of a photon (energy basicaly put). The universe was made this way.\n\nP.S.  A Wood's answer is the stupidest thing I have ever heard.  First of all, the big  bang does not state that it came from nothing, and second of all, the law of conservation of mass and energy is not newtonian law....  Jesus... such ignorance out there...
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Under the current Big Bang model the center of the universe is nowhere.  Ok. You don't like that, then how about the center of the universe is everywhere.\n\nThe Big Bang was not an explosion, the term "big bang" came from early opponents of the theory.  Basically it was the creation of space itself.  Subsequently that space has expanded, it is not expanding from somehwhere, it is expanding from everywhere.