Gravity and Mass: What's the Need for a Graviton?

[Uncle Peter]

Hello,

Please help an amateur understand. I don't see the need for a Graviton. I thought gravity was explained by: "Mass causes the curvature of space time". Hence objects "fall" toward each other in a sense; along the curved space time caused by their respective masses.

So why the need for this Graviton? There's the explanation above right? What am I missing?

Thanks!

 

[cragar]

mass or energy causes space-time to curve. By the success of quantum theory they think we need a particle to mediate the Gravitational force, Just like we have particles to mediate the other forces.

 

[{~}]

The graviton is just a way to quantize gravity into discreet non-divisible units like we do with other forces. So far all attempts to place a quantum frame work on gravity have seen little success. It is something of a physics enigma.

 

[mathman]

There are theories which attempt to unify gravity with the other three forces - string theory and loop quantum gravity. Both of them have the same basic problem. They have yet to come out with meaningful results which can be experimentally verified.