Physics:Quantum field theory in curved spacetime
Quantum field theory in curved spacetime studies quantum fields on a classical curved spacetime background. It is not a full theory of quantum gravity because the geometry is not itself quantized, but it captures important effects where matter fields are quantum while gravity is treated classically. It is central to Hawking radiation, the Unruh effect, cosmological particle creation, and semiclassical gravity.[1][2]
No unique particle concept
In flat spacetime, particles can often be defined using preferred modes and a preferred vacuum. In curved spacetime this definition can become observer-dependent or background-dependent, so the vacuum and particle content may not be unique.[3]
Important predictions
The framework predicts phenomena such as particle creation in expanding universes and Hawking radiation from black holes. These effects show how quantum fields can respond to horizons, acceleration, and changing geometry.[4]
Intermediate theory
QFT in curved spacetime is an intermediate step toward quantum gravity. It is expected to work when spacetime curvature is not Planckian and when the quantum fields do not strongly back-react on the geometry.[5]
See also
Table of contents (84 articles)
Index
Full contents
References
- ↑ "Quantum field theory in curved spacetime". https://en.wikipedia.org/wiki/Quantum_field_theory_in_curved_spacetime.
- ↑ Wald, Robert M. (1994). Quantum Field Theory in Curved Spacetime and Black Hole Thermodynamics. University of Chicago Press. ISBN 978-0-226-87027-4.
- ↑ Birrell, N. D.; Davies, P. C. W. (1982). Quantum Fields in Curved Space. Cambridge University Press. ISBN 978-0-521-27858-4.
- ↑ Wald, Robert M. (1994). Quantum Field Theory in Curved Spacetime and Black Hole Thermodynamics. University of Chicago Press. ISBN 978-0-226-87027-4.
- ↑ Rovelli, Carlo (2004). Quantum Gravity. Cambridge University Press. ISBN 978-0-521-83733-0.
Source attribution: Physics:Quantum field theory in curved spacetime