How can gravitons be linked to general relativity?

[haisydinh]

Hi, this might be a silly question, but it does confuse me when I read about general relativity. From what I know about quantum mechanics, a force always needs a force carrier. For example photons are force-carriers for electric or magnetic force; the so-called ‘gravitons’ are the force-carriers for gravitational force. However, general relativity states that gravity is not a force; it’s just the effects of the bending of space-time near a massive object. So why do we need the graviton at all? In other words, how can the graviton be linked to the bending of space-time?

Thank you :)

 

[UltrafastPED]

When you take GR in the weak gravitational limit (e.g., like Newtonian gravity), and quantize it ... you find these spin 2 bosons. These are what they call gravitons.

Whether or not they actually exist is another question.

But it is not quantum gravity, and it is not general relativity.

 

[jtbell]

Tip: if you look down at the bottom of this page, you will find a list of "Related Discussions" with the very same (or nearly same) question that you asked. This is a rather frequently asked question here.