activity
20242026
collaborators

9 papers

math.FA2026

On the existence of extremizers for the sum of eigenvalues of Toeplitz operators

Fabio Nicola, Federico Riccardi, Paolo Tilli

We prove that, among all measurable sets of prescribed Lebesgue measure, there exists a set maximizing the sum of the first eigenvalues () of the…

math.AP2026

A Phase Space Criterion for Dynamical Amrein-Berthier Uncertainty

Piero D'Ancona, Diego Fiorletta, Fabio Nicola

We prove a phase space criterion for dynamical Amrein-Berthier uncertainty principles. The abstract result says that, for a Fourier integral operator associated with…

math-ph2025

An elementary approach to Wehrl-type entropy bounds in quantitative form

Fabio Nicola, Federico Riccardi, Paolo Tilli

We consider the problem of the stability (with sharp exponent) of the Lieb--Solovej inequality for symmetric coherent states, which was obtained only recently by the author…

math-ph2025

The Wehrl-type entropy conjecture for symmetric coherent states: cases of equality and stability

Fabio Nicola, Federico Riccardi, Paolo Tilli

Lieb and Solovej proved that, for the symmetric representations, the corresponding Wehrl-type entropy is minimized by symmetric coherent states. However, the uniqueness of…

math-ph2025

The Hudson theorem in LCA groups and infinite quantum spin systems

Fabio Nicola, Federico Riccardi

The celebrated Hudson theorem states that the Gaussian functions in are the only functions whose Wigner distribution is everywhere positive. Motivated by quantum inf…

math.FA2025

The isoperimetric inequality for partial sums of Toeplitz eigenvalues in the Fock space

Fabio Nicola, Federico Riccardi, Paolo Tilli

We prove that, among all subsets having circular symmetry and prescribed measure, the ball is the only maximizer of the sum of the first eigenvalues ($K\…