3 papers
quant-ph2025
Entanglement negativity in free fermions: twisted characteristic polynomial, universal bounds, and area laws
Ryota Matsuda, Zongping Gong
We present a general and simple formula for computing the entanglement negativity in free fermions. Our formula allows for deriving several universal bounds on negativity and its r…
math.GT2025
On the spectrum of the number of geodesics and tight geodesics in the curve complex
Ryo Matsuda, Kanako Oie, Hiroshige Shiga
Let be an oriented surface of type . We are interested in geodesics in the curve complex of . In general, two -simplexes in have i…
math.CV2024
Maximal cusps are not dense
Ryo Matsuda
We proved that the Maximal cusp is not dense on the Bers boundary of the Teichmüller space of infinite type Riemann surfaces satisfying some analytic conditions. This is a countere…