What exactly is the big bang theory? Is it self expalantory - Do any of you believe in it?

Question

Just very curious - thanks!

Sorry if it's in the wrong category - didn't know where the heck to put it!

Answer 1

The big bang theory is a homogenious solution ( actually a pair of homogenious solutions ) to Einstein's General Theory of Relativity. One of the solutions describes an infinite universe and one describes a finite universe.

The solution was discovered independently in the late 1920s by three people ( Robertson, Friedman, and Walker ).

The solution was later enhanced by Guth who detailed the rapid inflation and explained the mechanism of how matter and energy formed in conjunction with equal amounts of Negative Gravitational Potential Energy.

The solution describes the rapid expansion of the observable portion of the universe. It is not in itself a theory of origins.

Yes I believe in it.

Answer 2

It's just an alternative explanation about how the physical universe came in to being; that from some spontaneous event all the materials needed to fabricate the universe as it is today sprung in to existence and from that time it's development has been an ongoing and mutable thing. I think it appeals greatly to those for whom God is a fiction instead of a fact.

Personally I neither believe it or disbelieve it because although I admit to getting on a bit I'm really not *that* old. I wasn't there, didn't see it happen and I don't know if it's right or not. The only thing I will say is that I find it plausible, and this is more than I can say of the notion that some divine being created everything.

If I had to choose between the Big Bang or God I'd have to go with the least preposterous (to my mind) and go with the Big Bang.

But in the end I prefer not to waste too much time thinking about things for which there will probably never be definite answers and focus more on the here and now.

Answer 3

The big bang theory came about when astronomers discovered that all the matter in the universe is flying away from each other at incredible speeds. (This is measured through the doppler shift of various objects in space.) It was suggested that the reason for this was a huge explosion sometime in the distant past. As we developed better instruments to study the universe, (devices to measure the cosmic background radiation, etc.) the evidence for the theory mounted. Put simply, this theory states that all the matter in the universe was once compressed into a space smaller than an electron. Something caused this matter to "explode", forcing time and space to expand, carrying the substance of the universe with it. At this point, the density was so great, that this substance could only exist as energy. As it expanded, and cooled, it coalesced into the forms of matter we know, starting with the simplest (hydrogen-also the most abundant element in the universe) and continuing on to more complex atomic forms. The evidence to support this theory is great, but it's the various ramifications of it that I find the most interesting. Among these:

1) Things don't just explode for no reason. So, what caused the big bang?

2) Considering the state of matter in the universe was only energy at first, would it not be just as accurate to say: In the beginning there was nothing, the universe was void and without form. Then (for some reason) the Big Bang occured and there was light. And it was good.

3) The laws of physics as they exist in this universe were just one of many possible quantum probabilities, and were not set until after the big bang occured. Thus, our physical laws are not the only ones that could have exsisted. What set them in their present form? Random probability? Or something else?

You probably see what I'm driving at here. There is almost no other scientific theory that supports so well the idea of a creator. This is why I don't understand why so many fundies (whose recriminations you will undoubtedly see on this question) oppose this theory so violently. Indeed, the big bang theory corresponds to the Biblical account of creation on almost a point by point basis with one exception: Time scale. But then, the Bible itself states: "A day to God is as a thousand years, and a thousand years is as a day." I guess they just don't understand what the theory says, and are predisposed by their upbringing to unthinkingly view all science and scientists as the "enemy" of faith. "Predjudice must needs scapegoats" Anyway, I hope this answers your question.

Answer 4

"Big bang" is just a nick-name.
It was no "explosion" in any conventional sense.

The idea that in the past the whole universe was much more dense and compressed came from observations of the universe as we see it.
The earliest version was perhaps proposed by Georges Lemaitre, a Catholic priest.
(The Father of cosmology... old astronomical joke)

Although at first sceptical, Einstein came round to this basic model being a more accurate representation of the history of the universe than the alternate "steady state" theory of an infinite unchanging universe with which it had to compete.

Pushing the "Big Bang " back further in time than a massive blob like a gigantic star was a matter of astronomical observation and mathematical work in physics and relativity.

The "Big Bang" is not the sudden explosion of matter from nowhere into space.
It's the beginning of space AND matter. It's not just matter expanding, as from an explosion. SPACE expands from this point, too.
As in many areas touching on relativity and quantum effects, this is non-intuitive. Our brains are set to work with the bit of the universe we experience at a human size and timescale.

Why is it held, then? Because it fits so many bits of data:
from the observations of the largest telescopes and infrared detectors, down to the details found colliding subatomic particles together.
Yes, the detailed picture is continually being adjusted as more information comes in, but any new "big idea" about the early universe would have to be a better fit with all that is already known. And that's a VERY tall order.

The biggest mystery at the moment?
What is dark matter, and dark energy, and how do they fit into the big picture, as they're a big part of it.

I believe the "Big Bang" is by far the best explanation we've got. Yes, it still needs work, but that's fine.

Answer 5

The Big Bang - as some have stated - was a singularity that "exploded".

All the matter in the universe was compressed into 1 "dot" of matter. There is no measurement of this dot since there was nothing else to measure it against. There was no time since there was no entropy nor any movement of mass since all the mass was contained in one dot. All our theories break down just before the "explosion".

The explosion released all the matter of the universe and huge amounts of energy. This created all the things in the universe - all the atoms, molecules, stars, nebulas etc...

There are theories about whether or not our universe will ever start contracting back into a single point (back to a singularity). If it does, then the entire cycle may repeat itself in several hundred billion years. If it doesn't then everything will continue to spread out infinitum.

There is no explanation of the existance of that dot. Since there was no time before the "bang" there is no way to look back to see where it came from. However, since the universe is infinitely large, it stands to reason that infinite time also exists and the "dot" has always been here.

Infinity is a tough thing for the mind to grasp :)

This is my layman's nutshell version anyway.

Answer 6

I do not believe anything, since beliefs are accepted with no proof at all, but I accept things that have some proof, and there is much scientific evidence for the Big Bang that once competed with Steady State cosmology, but the evidence has favored the Big Bang for some years. About 14,000,000,000 years or so ago, there was just one sort of an atom that contained all the matter and energy in the universe, and it exploded, so that matter and energy were blown outward and are still moving outward. There is no real alternative to the BB now. Naive myths are only fantasies.

Answer 7

The "Big Bang" theory purports to explain the existence of the universe by stating that ALL the matter in the universe, and ALL the energy in the universe was at one time (80 billion years ago, according to some scientists) all compressed down into one "egg" (sorry for the metaphor), and that this "egg" exploded (80 billion years ago) and this explosion resulted in the universe as we know it.

My problem with this is, what was here prior to this "egg"? And if this "egg" had already been here, why did it wait so long to explode?

I mean, if this "egg" was eternal, then it should have exploded an infinite time ago, and according to the laws of thermodynamics, the universe would have been "born" an infinite time ago, and would have died out long ago.

If the "egg" was NOT eternal - that is to say, if the egg was not that old - then how did it get here?

At SOME point in time, there had to be absolutely NOTHING. If there was NEVER a time in which there was absolutely nothing, then the laws of science would have been in operation, and the universe would have died out by now.

(Again, if you say that the universe isn't old enough to have died out by now, we have the dilemma that the universe has an actual measurable age, prior to which it didn't exist) - this thinking includes this initial "egg".

Answer 8

The big bang theory states that the universe expanded from a singularity, a point of infinite density. Scientist have actually seen "pictures" of the Big Bang in it's infancy, using the WMAP satellite which maps out temperature variances in the cosmic microwave background. The fact that the universe is expanding is also a big indicator that the universe was somehow created through the Big Bang. Big Bang theory is the dominant theory among scientists for the explanation of the creation of our universe.

Answer 9

The big bang theory is the way that most scientists believe the universe came into existence. All the matter and anti-matter of the universe was crushed into one point. It then expanded ver quickly, at that point the universe came into being and time started (there was no time before this). The universe also cooled very quickly ands as it cooled -first quarks could bind to make protons, neutrons and Electrons (as well as many other particles), then these could combine to make atoms and then these could collide and interact to make further elements (fusion as still happens in stars today). The entire theory is too complicated to explain here.

Answer 10

The foundation of existence must be spiritual..

Space contains hydrogen, Where from we don`t know.
Hydrogen colliding causing a chain reaction which in turn produces carbon. Carbon is the basic to all life, as we know it.


As the entire universe is spreading outwards at a steady rate, it must have all come from the same point, and by reverse calculations it is possible the pin point the exact time of the begining of the universe. This begining is the big bang of the big bang theory..!!