5 papers
Numerical analysis of spin foam dynamics and the flatness problem
Pietro Dona, Francesco Gozzini, Giorgio Sarno
In this paper, we apply a recently proposed numerical algorithm for finding stationary phase points in spin foam amplitudes. We study a spin foam amplitude with three vertices and…
Typical entanglement entropy in the presence of a center: Page curve and its variance
Eugenio Bianchi, Pietro Dona
In a quantum system in a pure state, a subsystem generally has a nonzero entropy because of entanglement with the rest of the system. Is the average entanglement entropy of pure st…
Numerical study of the Lorentzian Engle-Pereira-Rovelli-Livine spin foam amplitude
Pietro Dona, Marco Fanizza, Giorgio Sarno +1
The Lorentzian EPRL spin foam amplitude for loop quantum gravity is a multi-dimensional non-compact integral of highly oscillating functions. Using a method based on the decomposit…
Entanglement entropy of Bell-network states in LQG: Analytical and numerical results
Eugenio Bianchi, Pietro Dona, Ilya Vilensky
Bell-network states are loop-quantum-gravity states that glue quantum polyhedra with entanglement. We present an algorithm and a code that evaluates the reduced density matrix of a…
Numerical methods for EPRL spin foam transition amplitudes and Lorentzian recoupling theory
Pietro Dona, Giorgio Sarno
The intricated combinatorial structure and the non-compactness of the Lorentz group have always made the computation of EPRL spin foam transition amplitudes a ve…