can someone explain the big bang theory in the simplest terms?

Question

and does gravity have something to do with it?

Answer 1

Bang!!! And it happened.

Answer 2

There are several theories (none proven) about just how the Big Bang occurred. Without going into things like quantum mechanics, zero-point-energy, etc., it's best to first try and imagine an absolute and infinite void totally without any mass, energy or spacetime. Somehow--repeat, somehow--at a single point in this void our universe burst forth.

Now things get REALLY weird. In the very first instant of the Big Bang all of space and time were created and for one brief moment expanded faster than the speed of light. This is the so-called 'inflationary period,' and is allowed because Einstein's relativity only prohibits mass from moving faster than the speed of light. Space can.

After the inflationary phase, at T+ 10^ minus 6 seconds,the temperature of the entire universe was greater than 10^12 Kelvin and consisted of a kind of quark-gluon plasma. At T + 10^ minus 4 seconds the temperature had decreased to a point where the first individual protons and neutrons could form, and then at T + 3 minutes low-mass atomic nuclei first appeared. Not until some 400,000 years after the Big Bang event did the first neutral atoms form. All the time the universe is expanding and cooling. Somewhere around 1^9 years after the Big Bang the first stars probably formed. The rest, so to speak, is history--stars formed into galaxies, planets evolved, life appeared on some of them, and here we are today.

In a nutshell that's the story of the universe up to today. A few words of caution--(1)try not to think of the Big Bang as an explosion. An explosion has a center, but the universe doesn't; it's what's called 'isotropic,' meaning that no matter where you are in the universe it looks the same in all directions. Nor does the cosmos have an edge or boundary, again because it's isotropic. If we look at galaxy 'A' which might be 9-billion light years away we'll find that it's rushing away from us at a high velocity. This would seem to indicate that we're at the center of the universe, but if we were in galaxy 'A' looking back at the Milky Way galaxy it too would be rushing away at the same high velocity (2) remember also that in a sense there are two universes, the observable universe into which we can see some 13.7-billion light years, and The Universe, much of which is receding from us so fast that light will never be able to reach us.

There are a gazillion unanswered questions about our universe, but the Big Bang theory so far contains the best concepts of how it began, evolved, and will continue to evolve.

Religious fundamentalist flatly deny the Big Bang theory because they believe that it contradicts THEIR interpretation of the Bible. The truly pathetic thing about this attitude is that it's completely reasonable and even logical that some Ultimate Power was directly involved. Science and God are not mutually exclusive!

Answer 3

Our universe was extremely small. It would be beyond microscopic by comparison. Current theories suggest that extremely dense matter that occupied all points in this extremely small universe just one day let go, and BANG! Another thoery is that 2 pieces of extremely dense "Micro Universes" colided and caused the Big bang. Kind of like sending two 5 mile long freight trains filled with Hydrogen colliding on the same track head on. Now, the explosion caused the huge expanse of "Space" as we know it and is still expanding. The initial expansion immediately after the big bang was fast. Faster than light fast. And now everything that is restricted to the speed of light is expanding at a constant rate trying to catch up.

As far as gravity, no one really knows. All we have are theories, but what we do know is that matter has gravity, and the more dense an object, the more gravity it has.

Answer 4

The big bang theory is a little like the atomic theory used to make the A Bomb, except on a much larger scale.

Matter in the universe (helium, hydrogen), clumps together because of attraction and gravity. Eventually big clumps attract smaller clumps. Eventually huge clumps attract everthing around.

Now, after this point people can take different route. We have one huge ball of mass that explodes or becomes a small singularity or black hole that explodes.

But the idea is that a "critical mass" that can no longer be compressed by gravity at the rate of growth causes an atomic reaction that send spews all this matter out at great speeds and as the central mass grows smaller there is less gravity from the original mass and the stuff keeps going out into space.

Eventually, some say, it falls back on itself and another big bang would occur in trillions of years after gravity takes it's toll on the moving masses of starts and galaxied and they all draw back to some point (black hole, large mass of objects) and once again compress

Matter can not be created or destroyed only converted to some other form.

Energy is matter moving at an excelerated speed of light squared.

Matter comes together in wahtever form, emasses, grows, has weight, creates gravity, attracts other matter, compresses, atoms start bouncing as this compression continues BANG, enegery is release (small mater particles sent out at the speed of light) and mass or matter is spewed out at great speeds (near light).

Answer 5

1. There were only dust and gaseous clouds in the universe. Nebula.
2. over the years, due to gravitational forces, the mass of dust/cloud started lumping up.
3. As the mass grown was high as well as due to gaseous substance there was a collapse and began to rotate.
4. The spinning disc* over the years formed as solar system.
5. Planets nearer to the Sun because of the heat, gases did not freeze where dust was the main content and hence rocky planets of mercury, Venus, Earth and mars.
6. planets far away from Sun the gaseous substances froze and they became giant gaseous mass such as Jupiter, Saturn, Uranus and Neptune.
N.B*.: The thickest centre disc of gas and dust when collapsed became more and more compressed and thus hotter and hotter. The temperature and pressures became incredibly high. Atoms of hydrogen began to combine or fuse together and nuclear actions gave out enormous energy. This made the mass shine and turn into a star, our Sun.

Answer 6

It is quite possible that all the matter in the universe was created in a single location (singularity) and that the gravity and other forces were created at the same time. This would negate the possibilty at that instance for "time" as we know it but would be the instant that "time" itself was created. As the resultant "explosion" (to be a mild term compared to what happened) the matter was thrown outward from the created point. As the matter grew farther and farther separated from that point weaker forces (like molecular bonding) and gravity could take over.

Or....

Too much stuff in one place....BANG!

Answer 7

something from nothing. Those are about the simplest terms I can think of. The something is everything. Not only spacetime itself, but everything in the fabric of spacetime. IF this makes you ask, what was outside of it before it began its expansion, I would have to say the question is irrelevant. The reason being If there is something outside our universe, we can never interact with it, so for all intents and purposes, it does not exist.

Answer 8

Meteors hit the earth with alot of force and broke the earth's crust. Lots of hot lava fields rose from the break in the earth and covered the earth. Not only did the lava burn objects, but also filled the air with carbon dioxide, which in turn started a greenhouse effect and made tempuratures rise to extreme points.

Answer 9

There was a lot of matter. It all got compressed into such a tiny space that it exploded. All the matter was shot outwards to form the solar system, galixies, planets, stars, nebulas, astroids, meteors, comets, and Earth.

Answer 10

Matter exploded and is pushing farther into the universe. Gravity has something to do with everything.

Answer 11

Simplest accurate explanation I've seen:

"In the beginning, there was nothing, which exploded."