in unified field theory why only 4 forces are considered ?

Answer 1

Only 4 fundamental forces are considerered in physics because that's all that have been found. Others have been hypothesized--but so far no one's been able to come up with evidence to back up such hypotheses.

But it's NOT "unified field theory." That's a label for a theory that would reconcile inconsistancies between "macro" (relativity) theory and "micro" (quantuum) theory. The idea of a unified theory has been around since before World War 2. Most physicists think we'll eventually develop just such a theory--but so far that hasn't been done (though not from lack of trying).

The motive for hunding for a UFT is that right now, those two theories--relativity and quantum theory--are the two basic models physicists have. Bot h are valid--with massive amounts of evidence to support them. But they describe different phenomenonae--and they don't seemm to be consistant with each other. A UFT that ties both theories toghether into a single, self-consistant whole would be a scientific breakthrough as great as Newton's laws of motion or Einstein's theory of relativity. And--might (almost certainly would) lead to other scientific advances and new technology we can only speculate about right now.

Answer 2

It is not clear what you mean. Generally, a "Unified Field Theory" would unify all the known forces: gravity, electricity, magnetism, the strong force, and the weak force. Since electricity and magnetism were unified over 150 years ago, they are sometimes considered one force. The "Standard Theory" unifies electromagnetism, the strong force, and the weak force. Gravity remains ununified. It is not clear whether "Dark Energy" is yet another type of force.

Answer 3

Because there are only four forces of nature, electromagnetism, weak nuclear, strong nuclear, and gravity (supposedly). I say supposedly for gravity because no unified field theory has been able to successfully incorporate gravity into the theory, and according to General Relativity gravity is not a real force but a fictitious force that arises out of the situation.
Since General Relativity came out, no attempt at quantizing gravity has been successful.

I'm sorry I kinda went off subject, but I hope I answered your question.

Answer 4

What precisely do you recommend as a theory of each and every thing? A theory explaining how each and every thing works? A theory clarify how each and every thing have been given here? A theory explaining why each and every thing is here? i does no longer say that any of those are inevitable, looking some thing so encompassing that it might desire to word to each little thing interior the universe may be nigh impossible. inspite of the shown fact that, I bypass away you with this to contemplate: "there's a theory which states that if ever all and sundry discovers precisely what the Universe is for and why it relatively is here, it is going to at once disappear and get replaced with the aid of some thing much greater extraordinary and inexplicable. there is yet another theory which states that this has already handed off." ~Douglas Adams

Answer 5

What the world physics means by four forces of nature is really a description of the different magnetudes
of force that occurs as a result of micromass interactions and macromass interaction.
The confusion arises Because The cause of force has not been exactly identified By Physisits.
Force is defined as Energy per unit distance or Power per Unit velocity.
Therefore a Force is a Force it does one thing and one thing only=Its own thing.

Answer 6

We have only discovered 4 basic forces - electromagnetic, strong, weak, and gravity. And FYI, we already have unified the first three.

Answer 7

I am curious. What other force are you speaking of?

I believe there are more then 4 forces.

"For every action there is an equal and opposite reaction"

If this statement is really a Law of Nature, this means that there may well be dark forces, like dark matter and Dark energy that react to the forces that we know.

Answer 8

NEWS - North, East, South and West Directions. There is no more than these 4 Please.