Hey gUyz,. what are the theories of the earth??,, bigbang theory,nebula theory, and what are the others??

Question

what are the other theories aside from what i've mentioned. I think, there are 6...

Answer 1

As already mentioned -- big bang is about the universe, not earth.  

From there you have star formation theory, which deals with how stars were made.

Once all the material to make a planet was forged in a star (or many stars) and they explode, then you get to planetary formation theory.  (i.e. the Nebula theory you mention).  

Generally there's only 1 theory at a time for any scientific area, because a theory, in science, is much more than a guess -- it's a tested model that explains all the known facts better than any other.  Some theories are "stronger" than others because scientists have a general idea about how much they haven't investigated yet.  (Kind of like thinking you know who the murderer is but you haven't checked out his home and toolshed yet... All the pieces so far point to him, but you know there's a possibility of finding something else that clears his name.)

Answer 2

Big Bang can't be bothered with something as tiny as Earth.  It deals with a whole universe and its expansion.

The collapsing cloud (nebula) theory explains how the solar system forms out of a cloud of dust and gas that falls onto itself (under its own gravity).

The tidal drop theory (no longer a theory, I think) says that the planets were formed after the sun was formed.  Another star passed close and the tidal effect lifted a large glob of solar matter that left the sun, cooled and formed the planets.  This was abandoned after the age of the planets became measurable (they formed while the Sun was still a proto-star).

Answer 3

Theories of the earth's *what*? The Big Bang has nothing to do with the origins of earth, just the origin of the universe. The earth came several billion years later.

Look at my source for a pretty broad overview of the earth's history.

Answer 4

Your question asks about the earth, but your mentioned theories are about the universe.  Good science textbooks will show both sides of the equation.  So, to add to your list, consider the Creationist view also.  Hope it helps.