# Quantum Gravity in Relation to Gravitational Waves

1. Dec 10, 2008

### Ignoramus

As I am fairly new here (been a lurker for a long while), I was not quite sure where to post this topic as it has Relativistic and Quantum Mechanical basis. Apologies if this is the incorrect place.

It's not a homework question in any sense, but I'm doing a project for my Advanced Science Topics class at school on Gravitational Waves/ GW mechanics/ GW implications. After showing it to my teacher, he suggested I add in how Gravitational Waves can help pursue a Quantum Theory of Gravity. I have tried doing some research, but to no avail (except for finding little wiki bits saying dumb things such as "if gravitational waves are found to travel slower than the speed of light, then it can be inferred that gravitons have mass"). I was wondering if anybody could give me some glimpse of an idea how to relate the two, since I do not know where to look, or what to think.

Thanks!

2. Dec 15, 2008

### Naty1

Go back and ask what that means...that you find no connection!!! Post what he/she suggests here...especially if you are in High School his advice is a TALL,TALL order!!!

Gravitational waves have not yet been observed: Riddle of Gravitation, Peter Bergmann
Wiki says they have been indirectly observed. LIGO is trying..

Have you read wikipedia, Loop Quantum Gravity? It discusses a number of possible theoretical relationships between quantum theory and relativity....and I saw nothing there to help you. LQG is relativity based.

I've read roughly a dozen books that in part discuss both theories, by Smolin,Kaku,Greene, others and I can't think of anything they mentioned...Greene mentions Einstein recognized the likelihood of gravitational waves bewteen 1916 and 1918...hardly a recent insight!!

The only connection I know is that relativity is background independent, meaning spacetime is dynamic and not rigid,not fixed, so direct evidence gravitational waves would further strengthen that concept. Hence Loop quantum gravity which is also mathematically background independent would potentially gain credence; however all this has been known for years so it's of little significance as far as I can tell.

3. Dec 15, 2008

### atyy

Maybe your teacher is thinking of these crackpots:

On the interaction of mesoscopic quantum systems with gravity
Claus Kiefer, Carsten Weber
http://arxiv.org/abs/gr-qc/0408010

The Interface between Quantum Mechanics and General Relativity
Raymond Y. Chiao
http://arxiv.org/abs/quant-ph/0601193

Edit: There are lots of crackpots out there - some even have Nobel Prizes in Physics. So beware!

Last edited: Dec 15, 2008