collaborators

5 papers

math.PR2026

The End of the Double Random Current

Ulrik Thinggaard Hansen, Frederik Ravn Klausen

The Ising correlation function can be expressed in terms of connectivity probabilities of a random graph known as the double random current. In 2016, Duminil-Copin asked whether th…

math.PR2026

The Supercritical Loop O(1) and Random Current models: Uniqueness and Mixing

Ulrik Thinggaard Hansen, Frederik Ravn Klausen

Much recent rigorous study of the classical ferromagnetic Ising model has been powered by its graphical representations, such as the random current and loop O(1) model (high temper…

math.PR2025

Non-uniqueness of phase transitions for graphical representations of the Ising model on tree-like graphs

Ulrik Thinggaard Hansen, Frederik Ravn Klausen, Peter Wildemann

We consider the graphical representations of the Ising model on tree-like graphs. We construct a class of graphs on which the loop model and the single random curre…

math.PR2025

A General Coupling for Ising Models and Beyond

Ulrik Thinggaard Hansen, Jianping Jiang, Frederik Ravn Klausen

The couplings between the Ising model and its graphical representations, the random-cluster, random current and loop models, are put on common footing through a gen…

math.PR2025

The Uniform Even Subgraph and Its Connection to Phase Transitions of Graphical Representations of the Ising Model

Ulrik Thinggaard Hansen, Boris Kjær, Frederik Ravn Klausen

The uniform even subgraph is intimately related to the Ising model, the random-cluster model, the random current model, and the loop (1) model. In this paper, we first…