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 advanced_notions:quantum_field_theory:qft_curved_spacetime [2018/05/30 06:18]89.12.128.15 [Intuitive] advanced_notions:quantum_field_theory:qft_curved_spacetime [2018/05/30 06:21] (current)89.12.128.15 [Intuitive] Both sides previous revision Previous revision 2018/05/30 06:21 [Intuitive] 2018/05/30 06:18 [Intuitive] 2018/05/27 14:47 jakobadmin 2018/05/27 14:47 jakobadmin created 2018/05/30 06:21 [Intuitive] 2018/05/30 06:18 [Intuitive] 2018/05/27 14:47 jakobadmin 2018/05/27 14:47 jakobadmin created Line 4: Line 4: Since in general relativity the curvature corresponds to the gravitational field, QFT in curved spacetime corresponds to a normal QFT with an external source (=the gravitational field). Since in general relativity the curvature corresponds to the gravitational field, QFT in curved spacetime corresponds to a normal QFT with an external source (=the gravitational field). - For a curvature that depends on the time, we are dealing with a time varying source that can, for example, produce particles. ​ + For a curvature that depends on the time, we are dealing with a time varying source that can, for example, produce particles. A proper analogy is a driven harmonic oscillator. - + - A proper analogy is a driven harmonic oscillator. + + It is important to note that QFT in curved spacetime is not quantum gravity. In a theory of quantum gravity we would take the backreaction of quantum effects on the spactime into account. In contrast, in curved spacetime QFT the curved spacetime is merely a background structure, i.e. an external source and not treated quantum mechanically. ​ ​ ​