Hi there,

 

I'm nowhere near an educated Physicist, but I have a healthy interest in the subject.

 

So according to M-theory, we're all living on a membrane, next to a lot of other membranes, and nothing can escape this membrane, except Gravitons, which explains why gravity as a force is much weaker than the 3 other forces.

 

Then I've also read that the Higgs boson may be the elementary particle that gives mass to all other particles (quarks and leptons) and the W and Z bosons, and that there is, hypothetically, a Higgs field in which our Universe (and if there are any, all other universes) is completely submerged.

 

String theory says that gravitons are closed strings without loose ends, which enables them to "leak out" of our universe into others, and that all other elementary particles are strings as well.

The Higgs boson is supposed to be an elementary particle too, which makes it a string as well.

 

So my question is: What is the relation between a graviton and the Higgs boson? Are they two names for the same thing? Or is something else going on?

If the Higgs exists, then it is not expected to be the same thing as a graviton.

 

Forgetting anything like a composite Higgs, the graviton is massless and spin 2 where the Higgs is massive and spin 0.

Ok,

 

So if LHC proves the existence of the Higgs boson, does that mean the graviton cannot exist?

Or can they coexist?

Coexist. The forces are not unified, at least at the energies under investigation.

Ok,

 

So if LHC proves the existence of the Higgs boson, does that mean the graviton cannot exist?

Or can they coexist?

 

Exactly as Swansont states.

 

Is it the fact that the Higgs gives mass as where the gravity's source is mass (and energy) that is confusing you here?

The Higgs boson (and the Higgs mechanism) is the ugliest part of the Standard Model, so in one sense I hope it isn't true.

 

On the other hand, I hope it is true because Peter Higgs is a friend of mine, and I want him to win the Nobel Prize.

And here his is getting his Honorary Fellowship by Swansea university, where I went as an undergraduate.