Entanglement in Quantum Field Theory and Quantum Gravity - Lecture 1

Dive into the first lecture of a series on entanglement in quantum field theory and quantum gravity, delivered by Tom Hartman at the Kavli Asian Winter School on Strings, Particles and Cosmology. Explore fundamental concepts such as Euclidean path integrals, quantum states defined by cut path integrals, and operators defined by path integrals with two cuts. Examine quantum entropy, coarse-grained entropy, and their applications to Unruh radiation and thermofield double states. Investigate entanglement entropy in 2D conformal field theory using the replica method. Engage with multiple Q&A sessions throughout the lecture, providing opportunities for deeper understanding and clarification of complex topics in theoretical physics.

Start
Entanglement in QFT and Quantum Gravity Lecture 1
Euclidean Path Integrals in QFT
A cut path integral defines a quantum state
Example 2
Path Integral with 2 cuts define an operator
Q&A
Quantum Entropy
Course Grained Entropy
Application #1: Unruh Radiation & TFD
Re-interpret
Upshot
Interpretation in Lorenzion
Q&A
Trace out B
Application #2: EE in 2d CFT
Replica Method
Q&A
Wrap Up