Theory · Physics
Quantum Gravity
Cosmology & UniverseActive Research
Definition
The sought-after theory that would unify general relativity with quantum mechanics.
Scientific overview
General relativity governs the very large and quantum mechanics the very small, but the two are mathematically incompatible where both matter — inside black holes and at the Big Bang. Approaches such as string theory and loop quantum gravity aim to unify them, but none is confirmed.
Open questions
- How do gravity and quantum mechanics unify?
- What replaces the singularity inside a black hole?
Rests on
Related topics
Knowledge connections
- Related toGravity
- Related toGravitational Singularity
- Related toHawking Radiation
- Depends onGeneral Relativity
- Related toGravitational Singularity
- Required byHawking Radiation
- Related toThe Standard Model (overview)
- Associated withThe Fundamental Forces
- Associated withThe Cosmological Constant Problem
Sources & references
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.