What is a Graviton?
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The graviton is a hypothetical particle that would introduce gravity into Quantum Mechanics, causing many physicists to desperately search for this particle.
The graviton would be a boson (that is, a particle that carries a force, in this case, would carry gravity) of null mass and spin 2. In addition, this particle would move at the speed of light, reaffirming to Relativity, that Says that gravity acts at the same speed as light. The graviton's biggest problem is that it carries very little energy, for gravity is the weakest of the four fundamental forces. Let's look at an example.
While reading this, you notice several types of "electromagnetic force": the light from the screen, the light from the light bulb that is on, the heat from the heating ... Instead, you only notice a "gravitational force": from the earth. It is true that other objects are exerting their gravitational force on you, but that force is so weak that you do not even notice it.
For this reason, the graviton must have a very small energy, which complicates its search. In addition, another problem arises. As we saw in the entry on Relativity, gravity deforms space-time. Therefore, the graviton not only travels through space-time at the speed of light, but in its passage deforms the spatiotemporal tissue itself. What makes this particle even rarer.
The existence of this particle would solve a great problem in Quantum Mechanics. In this theory, gravity could not be introduced because infinities appear in the equations. What is an impossible thing, because they can not appear infinite in the Universe.
More details here the link: graviton
Here an explanatory video:
Video credits: The Interesting Universe
