In-in correlators and scattering amplitudes on a causal set
Physical Review D(2024)
摘要
Causal set theory is an approach to quantum gravity in which spacetime is
fundamentally discrete at the Planck scale and takes the form of a Lorentzian
lattice, or "casual set", from which continuum spacetime emerges in a
large-scale (low-energy) approximation. In this work, we present new
developments in the framework of interacting quantum field theory on causal
sets. We derive a diagrammatic expansion for in-in correlators in local scalar
field theories with finite polynomial interactions. We outline how these same
correlators can be computed using the double-path integral which acts as a
generating functional for the in-in correlators. We modify the in-in generating
functional to obtain a generating functional for in-out correlators. We define
a notion of scattering amplitudes on causal sets with non-interacting past and
future regions and verify that they are given by S-matrix elements (matrix
elements of the time-evolution operator). We describe how these formal
developments can be implemented to compute early universe observables under the
assumption that spacetime is fundamentally discrete.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要