Event date:
Jan 19 2023 6:00 pm

Dynamics and entanglement in quantum and quantum-classical systems: lessons for gravity

Mr. Irfan Javed, PhD Student, University of New Brunswick
SBASSE 10-302 (Zoom Streaming)
Motivated by quantum gravity, semiclassical theory, and quantum theory on curved spacetimes, we study the system of an oscillator coupled to two spin-1/2 particles. This model provides a prototype for comparing three types of dynamics: the full quantum theory, the classical oscillator with spin backreaction, and spins propagating on a fixed oscillator background. From calculations of oscillator and entanglement entropy evolution, we find that the three systems give equivalent dynamics for sufficiently weak oscillator-spin couplings but deviate significantly for intermediate couplings. These results suggest that semiclassical dynamics with backreaction does not provide a suitable intermediate regime between quantum gravity and quantum theory on curved spacetime.

I am a pursuing a Ph.D. in quantum gravity at the University of New Brunswick, and I am interested in various approaches to quantum gravity, including but not limited to canonical quantum gravity, loop quantum gravity, and string theory. Currently, I am engaged in exploring the limits of semiclassical gravity.