How many theories of relativity are there besides Einstein's?
827901
There were others including Galileo that Einstein used to help explain how his own theory was developed. These were used by others to try and explain the final results of the famous work by Michelson and Morley which proved that there was no ether. Fitzgerald from Ireland was his greatest contributor as well as Lorentz to the ultimate development of his own theory.
236771
Try this link - it's Relativity in very short words.\n\nhttp://www.muppetlabs.com/~breadbox/txt/al.html
29195
There are actually two theories of relativity: special relativity and general relativity. \n\nIn a nutshell, relativity was Einstein's way of saying that nature always appears to have the same laws, no matter where or what you are. And it does this without having to have some sort of base reference place in the universe, or a base time. If you are on a plane going real fast, the speed of light always seems to be the speed of light. Special relativity accounts for this by things like time dilation (time moves at a different rate for you on the plane than for me on the ground.) Your size is different. Your weight is different. But to you it always seems the same.\n\nAnyway, it is a complex subject, and the easiest way to understand special relativity, the first of the two theories is this:\n\nhttp://en.wikipedia.org/wiki/Special_relativity_for_beginners
109471
Tests of general relativity
106733
Not to beat a dead horse, but it's Edward Witten.  The reason why though is because he was able to unify the several flavors of string theory into, one mathematically stable, unifying theory.  It suggests some pretty "out there" ideas, and its called M Theory.\n\nAlso, I noticed that somebody suggested that it took several scientists to match the power of Einstein's intellect.  However, Einstein did very little to establish laws for the very small, which was governed by Quantum Mechanics, a theory that he very much disliked.  Yet Quantum Mechanics has accurately described the very small for years over years.  So I wouldn't call Einstein irreplaceable.
72098
Some new ideas in physics posit that there are more than the obvious 3 spatial and 1 temporal dimension. These theories are intended to explain all four fundamental forces in nature (electromagnetism, the strong nuclear force, weak nuclear force and gravity) by serving as a bridge between quantum mechanics and general relativity.\n\nIt turns out that one way that - perhaps - QM and GR can be connected is to postulate some extra dimensions, with an extra 7 spatial dimensions for a total of 11. If such extra dimensions exist they may be too small to interact with our standard 3D+time word.\n\nSo, in this case, a 6th dimension would be one of these smaller extra dimensions.\n\nIt should be noted, though, that thus far string theories are very theoretical, and there is no real physical evidence (yet), nor even a complete theory. Its still very much up in the air.\n\nA nice, simple guide to string theory basics can be found here:
1179434
Relativityis the only way we currently have of trying to extend our ideas beyind the local to the rest of the universe.\n\nThis is because the intuitive assumptions that we can simply extend our frame of reference here on earth to fill the rest of the universe (like extending the lines on a map off the page into infinity) is simply wrong.\n\nThe fact that the speed of light is the same everywhere in the universe, regardless of how you are moving, means that there is a difference between the reference frames of observers moving relative to one another. You can fill the universe with the reference frame of either observer, but they are different and neither is preferred. This is special relativity.\n\nThe fact that gravity is indistinguishable from acceleration, and that the force of gravity is in opposite directions on either side of the centre of mass of a gravitating mass means that you cannot construct a single reference frame that fills all of the universe in a simple way. This is general relativity.
438820
No, but some physicists think they have.  String theory is the most popular unifying theory, but it makes no testable predictions, meaning that its really more philosophy than hard science.  There are other theories out there too.  For example , Heim Theory involves extra dimensions in which the speed of light is different in order to unify the four fources (electromagnetic, strong, weak, gravity).
61437
That would be Einstein's Special Theory of Relativity.\n\nhttp://science.howstuffworks.com/relativity3.htm
200414
what three theories..list them please.
457925
Well there are 3 spatial dimensions and one temporal dimension, so there's 4 to begin with. On a macroscopic scale the universe behaves like a minkowski space. However on a microscopic scale even 4 dimensions isn't enough, the maths suggests possibly 11 or more dimensions.\n\nHowever I have a feeling you're not talking in the strictly mathematical sense. If you meant "are there other universes 'beyond' ours", then I have no idea. There are theories that suggest there are, but as far as I know there are no known observations that could answer that yet. We'll just have to wait and see what is discovered.
1151026
According to classical physics 3: length, wideth and depth.\nModern physics add to that a fourth dimension - time.\nThose we now for certain exist. But there could be more (as much as 10 or 11 according to superstring theory).
724425
General relativity is not the final answer, since Einstein was never able to come up with the "Theory of Everything," i.e., the Grand Unified Theory.
42478
I think you have the wrong idea.  The reconciliation between the theory of relativity and Newtonian physics is intrinsic to relativity itself.  When you consider the theory of relativity in the limit of small magnitude velocities, you recover classical mechanics.\n\nI think you mean to ask whether there has been a theory combining the standard model of particle physics with the general theory of relativity in a manner that predicts both, and the answer is no.
745347
The theory of relativity is being used in Fermi lab, U.S. to "create" either energy or new matter from energy.  Newton's laws only define motion, but they do not explain why some of the mysteries of the solar sytem or the universe occur.  With Einstein's theory, however, these mysteries become clearer.  We understand more why they occur this way and can predict how much energy is being "created" by calculating for how much matter is "lost."  Fermi lab is working to create anti-matter, combine it with matter to create energy, and utilizing the energy into more matter -- it's one of their big projects.  I'm sure they're testing for more than that, but it's the overview of what they are doing.
444192
I think it is Albert Einstein... Einstein stated The Theory of Relativity, breaking down Isaac Newton's The laws of Three Motions and Theory of Gravitation, demonstrated that Newton's theories were only partially right. What is more, scientists believe that there will need more than 200 years for another "Einstein" be born in this world to help the innovation of Physics. Current Mathematics is not adequate for solving Physical problems any more.
292660
http://en.wikipedia.org/wiki/Theory_of_relativity