There are currently three main variations or iterations to the Big Bang Theory of science.
Author impression of the Universe as per the scientific theory of Big Bang from absolute nothing quantum vacuum, before the absolute nothing decided to become absolutely everything. The singularity shown here (which by right would also be totally black is denoted by a tiny black circle highlighted with a white border. All the blackness around this singularity is of course the other absolute nothing that is not even a singularity but just absolutely completely totally nada (no words to define as space-time does not exist so definition and information knowledge also do not exist) is magnified 1 trillion trillion times to the power of 1 trillion trillion.
Theory Number 1 (The Dense Ball Of Matter Theory). This first theory is both old and obsolete and can no longer be believed because it came from a time of mega super unenlightened mega super completely dark (which in scientific speak is not completely dark but just completely dark) age of mega super incredulous ignorance.
The Universe began as a mega super dense ball of matter of ‘undetermined’ size. This mega super dense ball of matter sometime 12 to 14 billion earth years ago then very quickly expanded but not exploded because it was a Big Bang and that is why it is in no way a big explosion.
This is because an explosion cannot be a bang and therefore a Big Bang cannot be a big explosion. This is the same reason whenever someone reported hearing a big bang they are always talking about an expansion. I can never make sense of this Big Bang an expansion not explosion thing (possibly because I am not a proclaimed and acclaimed Superlative of science). But science must have explained it extremely well because all the scientists understood and agreed that the Big Bang does not mean, is not, and never has been an explosion but an expansion which is the precise reason it is a Big Bang.
This mega super dense ball of matter of ‘undetermined’ size had existed forever in perpetuity eternally either as the same unchanged ball of matter until that Big Bang, or had been alternating in a never ending toggling between being a mega super dense ball of matter of ‘undetermined’ size and that of being a humongous large expanding universe which would then eventually collapse (i.e. reverse its expansion) back to the mega super dense ball of matter of ‘undetermined’ size.
The universe then after expanding but not exploding from a Big Bang, now after 12 to 14 billion earth years (the reason for the range of billions of earth years is to denote the many different given ‘ago’ times that science has being asserting the Big Bang happened since science first asserted in their theories that the universe began with a Big Bang some over a hundred years ago) has become our universe of which exist the planet earth we live in today.
Theory Number 2 (The Theory Of Singularity Quantum Absolute Vacuum plus variant Quantum Absolute Vacuum Not Absolute Nothing Big Bang). This theory may very soon become old and obsolete, even as it was just mooted, theorized, hypothesized and postulatized a few years ago (from 2015 C.E.) and may no longer be believed because it too will have came from a time of mega super unenlightened mega super completely dark (which in scientific speak is not completely dark but just complete dark) age of mega super ignorance of just a few years ago.
The Universe began as a mega super absolute nothing of a Singularity of a quantum absolutely nothing vacuum or quantum absolutely nothing near (i.e. almost) vacuum, both of which can either be a completely absolutely nothing or a not completely absolute nothing (i.e. an incomplete absolute nothing), or both or even neither at the same time, or not.
Obviously because this Singularity is a one dimensional point of a quantum absolutely nothing vacuum (or near almost vacuum) it could not have been really absolute nothing because if it had been really absolute nothing it could not have been a Singularity point even if that point is just a one (i.e. single) dimensional point or perhaps even less than one (single) dimensional if that is possible (which of course only science can know). This is because a point is still something (and thus not absolutely nothing) even when it is just a one or a less than one dimensional point. But the Singularity one dimensional point nonetheless was a true real quantum absolutely nothing vacuum or near (i.e. almost) vacuum. That Singularity one dimensional point quantum absolutely nothing vacuum (or nearly almost vacuum) had existed forever in perpetuity eternally in some place without space for a duration of time without time. This is because a one dimensional point of quantum absolute nothing vacuum (or nearly almost vacuum) does not need a place to exist in as it can both exist and not exist anywhere even when there is just only no where, and it does not need a time to exist for a period of time even as it could both exist and not exist forever perpetually without time prior to the Big Bang. The entire and only requirement is that it only just needed to be a one dimensional point Singularity of quantum absolute nothing vacuum or nearly almost vacuum that is not absolutely nothing (i.e. absolute vacuum).
Alternatively (i.e. as an alternative twist and spin to) this theory (or Theory Number 2a), for the Singularity to be quantum absolutely nothing vacuum while at the same perpetual duration of non time in no where, not to be an absolute vacuum (i.e. absolutely nothing) is by (or through) this Singularity of an quantum absolutely nothing vacuum existing forever in perpetuity eternally through the perpetual duration of non time somewhere in non existence space (i.e. in no where), in some all encompassing field or fields (of non quantum andor of anti quantum andor whatever, any, some or all being not absolute nothing, if there are any such) spread out completely covering the infinity of non existence space (i.e. of no where) through the perpetual duration of no duration (i.e. non existence time). This field or these fields (of whatever) existed everywhere in non existence space (i.e. no where) covering everywhere of non existence space (i.e. no where) forever in perpetuity eternally of no duration (i.e. in non existence time). This is because neither space nor time had yet to exist before the Big Bang.
This field (or these fields) is obviously not and must not be absolutely nothing (i.e. an absolute vacuum) but yet is a quantum absolute nothing vacuum so as to allow for the one dimensional point Singularity quantum absolute nothing vacuum to exist somewhere in no where (or non existent place of non existent space) for the perpetual duration of no duration (or non existent time) as a singularity one dimensional point quantum absolute nothing vacuum that is not an absolute vacuum (i.e. absolutely nothing).
And this Singularity of a one dimensional point of a quantum absolute nothing vacuum (or nearly almost vacuum) had existed forever in perpetuity eternally without time in some place without space except that together with it there may have been a field or some fields of non absolute vacuum (i.e. non absolute nothing) also existing forever in perpetuity eternally without time in some place without space.
This Singularity one dimensional point of a quantum absolutely nothing vacuum (or nearly almost vacuum) then very quickly (for whatever reasons or non reasons) expanded but not exploded in a Big Bang to become after 12 to 14 billion earth years, the universe that holds the planet earth we live in today.
Theory Number 3 (The Singularity/Dense Ball Energy/Gas Big Bang). This is the intermediate version between the singularity of absolute nothing (theory number 2) and that of a dense ball of gas (theory number 4) which is a version of the official NASA version.
The Universe either began: as a mega super dense ball of energy that started out only a few millimeters or a fraction of a millimeter across (whether as two or three dimensional ball of energy whether as particles, waves or both or whatever); or as a Singularity of energy (whether as particles, waves or both or whatever) of a one dimensional point. Which either then is dependent upon which scientists we listened to and believed.
And this dense ball or a Singularity of energy had existed forever in perpetuity eternally without time and space but yet still had existed, (for the former) as a two or three dimensional dense ball of energy, or (for the latter) as a one dimensional singularity of energy.
Then 12 to 14 billion earth years ago this very small dense ball of energy or a singularity of energy expanded (but not exploded) for whatever reasons or non reasons to finally become our universe of which we live in one of its planet, the planet earth today.
Theory Number 4 (The Dense Ball Of Gas Big Bang aka NASA official Big Bang). This is the current theory of a dense ball (or mess) of gas affirmed by NASA of the United States of America (or US or USA).
The Universe began as a mega super dense ball of gas that started out only a few millimeters or a fraction of a millimeter across (depending on which scientists we listen to) that had existed forever in perpetuity eternally without time and space but yet still have existed as a three (or even two or one, if these are possible as indeed anything and everything is possible when only just nowhere and no time existed) dimensional ball of gas.
Then 12 to 14 billion earth years ago this very small dense ball of gas expanded (but never exploded) for whatever reasons to finally become our universe of which we live in one of its planet, the planet earth today.
Prior To 14 Billion Earth Years Ago
Therefore in order for the Big Bang to happen some 12 to 14 billion earth years ago, somehow: a Singularity one dimension point of quantum absolutely nothing vacuum; or a Singularity one dimension point of energy or a mega dense ball of energy; or a mega super dense (one, two or three dimensional) ball of gas (i.e. plasma); or a mega super dense ball of matter must miraculously (or magically, paranormally or in anomaly, if you prefer one of these other terms) manage to miraculously (or magically, paranormally or in anomaly, if you prefer one of these other terms) miraculize (or magicalize, paranormalize or anomalize, if you prefer any of these other terms) itself to exist forever in perpetuity eternally somewhere in non existent space for a perpetual period of time in non existent time.
If all the above seems rather confusing andor contradictory andor irrationally illogical, that is only because they really, actually, fully, completely and totally are.
OK (added in on 2015 10 11), for the clueless who are just totally unable to put two and two together, which would include all the proclaimed and acclaimed Superlatives of science and their minions worshipers, let us just elaborate what the most modern, the most up to date science is saying.
While science for decades to centuries have ridiculed and mocked the supernatural and all things supernatural and magical (i.e. of things appearing out of ‘nowhere’ such as: bread falling from heaven to feed over a million people for decades; a rock spewing out a stream of water to supply the need of over a million people and their livestock; of time perceivably standing still and even reversing, etc), as utter ridiculousness (i.e. of fables and myths invented by the weak minded and the superstitious), the science of today are explicitly saying that these supernatural and magical (i.e. the paranormal and the anomaly of space-time and the universe) events are absolute infallible scientific facts. These science declared and decreed in their infallible facts of the theories of quantum entanglement and teleportation; space-time portals and wormholes; multi and parallel universe; parallel multi time tracks and the coexistence of past, present and future; and a whole humongous universe that materialized out of absolutely nothing from out of absolutely nowhere.
But scientists being the mega ego super gorgers they are, they totally deliberately pretend to be stupid so they don’t have to ‘eat humble pie’ (or ‘eat crow’) and be forced to have to admit that they have been totally wrong about the supernatural and the magical. So they come up with (i.e. invent) all these scientific terms to say the exact same thing but decreed and declared it as supreme mega super genius scientific discoveries and knowledge enlightenment. So then very naturally the supernatural and magical are only infallible facts and truths if and only if, they originate (come into existence or come into being) and were created in, from andor by the Big Bang whether of absolute nothing or of a super dense ball of energy or of a super dense ball of plasma gas. This supernatural or magical must not be of, must not come from or must not be created by the absolutely, totally, preposterously, ridiculous concept of an all knowing, all powerful intelligent Creator.
12 to 14 Billion Earth Years Later
And this universe today according to the latest science, is slowly dying.
CNN, CBS, Scientific America, Newsweek, NBC news of 2015 08 11:
1. ‘The Universe is slowly dying,’ study shows with unprecedented precision
2. It’s official: The universe is slowly dying
3. It’s Official: The Universe Is Dying Slowly
4. ‘The Universe Is Slowly Dying’
5. Massive Study Confirms Our Universe Is ‘Slowly Dying’
6. Falling energy levels in galaxies mean the Universe is slowly dying, say astronomers
7. Fading cosmos quantified in 21 colours