The Big Bang hypothesis is one of the theories that try to explain the origin of the creation of the universe. It's the current most accepted theory by scientists and astronomers. It asserts the universe and all the planets and systems it contains were formed after an immense explosion of matter and energy out of an original point.
universe
Hubble's red shift observation.
The Big Bang is a theory that discusses the origin of the universe (from a single point source of incredible density and energy) while the Nebular Hypothesis is a theory that discusses the origins of stars and their planetary systems (through the accretion of interstellar gas).
This theory (and PLEASE don't mis-use the word "theory" in a way that people, who are trying to advance a social agenda instead of truth, mis-use the word) explains things that are impossible to explain in any other way -- starting with the cosmic microwave background. All other hypotheses are relagated to saying, "We don't WHY there's a CMB, it's just there, and we can provide no answer for its origin." The Big Bang does a LOT better than that. So it's not only possible, it's the only hypothesis that matches the experimental evidence. And that's why it's a theory (like gravity) and not just a hypothesis.
This theory (and PLEASE don't mis-use the word "theory" in a way that people, who are trying to advance a social agenda instead of truth, mis-use the word) explains things that are impossible to explain in any other way -- starting with the cosmic microwave background. All other hypotheses are relagated to saying, "We don't WHY there's a CMB, it's just there, and we can provide no answer for its origin." The Big Bang does a LOT better than that. So it's not only possible, it's the only hypothesis that matches the experimental evidence. And that's why it's a theory (like gravity) and not just a hypothesis.
The Big Bang suggests that the universe is Time bound (or has a finite existence), that the universe is expanding (within the dimensional limits of Space and Time), that the universe is evolving a set amount of matter and energy while it is expanding over time, and that the universe is homogeneous and isotropic with respect to Space and Time.
A theory because a hypothesis is a plan that you had to think through to answer a question not to predict the big bang.
One can learn about the Big Bang theory that explains how the universe was created from a number of sources. For instance, the Big Bang theory is discussed in numerous science blogs, How Stuff Works, and Curious Astronomy.
No. The "Big Bang" hypothesis of the origin of the Universe developed in the 1930's and was widely ridiculed until about 1965 or so. In fact, the name "big bang" was coined by Sir Fred Hoyle, a British astronomer who intended to mock the idea.
Please note this succint quote from Alan Guth: "The Big Bang theory says nothing about what banged, why it banged, or what happened before it banged." So, although Big Bang Cosmology is the only idea that explains certain undeniable facts about our Universe, it does not explain -- indeed, it doesn't even TRY to explain -- the origin of our Universe.
the big bang
There's no way to know, and at the present time, there is no theory, hypothesis, suggestion, or conjecture that describes anything before the big bang. In fact, according to current thinking in Physics and Cosmology, the big bang was the origin of "time", so the very concept of "before" the big bang has no meaning.