3 papers
math-ph2025
Exponential decay in -invariant quantum spin systems
Jakob E. Björnberg, Kieran Ryan
We consider -invariant and reflection-positive quantum spin systems on the integer lattice in any dimension, and prove that spin-spin correlations decay exponentially fast pr…
math-ph2025
Dimerization in -invariant quantum spin chains
J. E. Björnberg, J. E. Björnberg, K. Ryan
We establish dimerization in -invariant quantum spin chains with large enough , in a much larger region of the phase diagram than previous results. This entails identifyin…
math.PR2024
A two-table theorem for a disordered Chinese restaurant process
Jakob E. Björnberg, Cécile Mailler, Peter Mörters +1
We investigate a disordered variant of Pitman's Chinese restaurant process where tables carry i.i.d. weights. Incoming customers choose to sit at an occupied table with a probabili…