Linked Questions

11
votes
1answer
2k views

Why does gravity need to be quantised?

The electroweak and strong forces seem to be completely different types of forces to gravity. The latter is geometric while the former are not (as far as I'm aware!). So why should they all be ...
15
votes
2answers
2k views

The Reeh-Schlieder theorem and quantum geometry

There have been some very nice discussions recently centered around the question of whether gravity and the geometry and topology of the classical world we see about us, could be phenomena which ...
4
votes
4answers
600 views

What predictions can a quantum gravity theory make?

Some of the major challenges that heralded the need for quantum mechanics we're explaining the photo-electric effect, the double-slit experiment, and electrons behavior in semi conductors. What are ...
9
votes
1answer
846 views

Is a QFT in a classical curved spacetime background a self-consistent theory?

EDIT: Better rewording by Chris White: Is it possible to have a theory that treats both GR and QFT (e.g. QFT on a curved spacetime dynamically influenced by the standard QFT fields)? Is such a theory ...
9
votes
2answers
825 views

What are the anomalies with General Relativity?

General relativity is the current model of gravity which has not yet been disproved. Are there still any anomalies such as the problem of Mercury's orbit during Newtonian gravity period that it failed ...
6
votes
3answers
451 views

Why to unify gravity with the other forces if gravity isn't really a force?

As I understand, the Theory of General Relativity says that the force of gravity doesn't exist. The planets move in elliptical orbits because the spacetime is curved by the mass of the sun, not ...
7
votes
0answers
535 views

Can the laws of quantum mechanics be derived from a more fundamental theory? [closed]

String theory takes quantum mechanics and tries to make it compatible with gravity. If it turns out to be a theory of everything then would it explain why our world is described by the laws of quantum ...
1
vote
2answers
148 views

Why do black holes need a quantum mechanical description?

I read about black holes, about the Schwarzschild metric, Einstein field equations and their solution in the vacuum for a spherical body. I understood black holes are object whose gravity is enormous,...
2
votes
1answer
105 views

Can Bohr-Kramers-Slater (BKS) theory examples be generalized to prove that classical gravity is futile?

In the comment in What are the reasons to expect that gravity should be quantized? by Ron Maimon, it is mentioned that taking analogy from classical electromagnetic wave to classical grvational wave, ...
3
votes
0answers
166 views

Why Shy away from non-local nature of gravitational energy/momentum?

Feel free to tear me a new one, This is something that has been bothering me a while. The very nature of attempting to write gravitational energy/momentum (called the stress energy pseudotensor), ...
1
vote
2answers
114 views

What is the motivation for developing a “theory of everything”?

What is the reason physicists are working so hard looking for a "theory of everything" and trying to unify gravity with quantum mechanics? Historically, new theories were always developed to explain ...
-1
votes
1answer
137 views

Quantum Theory as a framework for other theories of nature

We know that Quantum Theory should be considered as a framework in which all other theories/forces (Strong, Weak, EM and Gravity) exist. For example, we have the Quantum Chromodynamics, Quantum ...
2
votes
0answers
105 views

Is gravity quantized? [closed]

Two uncharged particles are placed in an empty universe one light year apart. In one year, they will feel each other's presence and begin attraction. We are ignoring the uncertainty principle in this ...
1
vote
0answers
95 views

I wondered what proof exist for the existence of gravitons?

It seems from my perspective that gravity is an indirect trait of matter; meaning that gravity is a trait of spacetime itself and that when matter interacts with spacetime, a bend occurs producing ...
2
votes
0answers
82 views

Isn't is far more likely that general relativity, and not QFT, is “wrong?” [duplicate]

At the risk/certainty of both sounding super ignorant and talking out of my arse, I have always wondered why there is some big mystery about why there are contradictions between the predictions ...

15 30 50 per page