8 citations · 16 across the 14 of their papers we have counts for
14 papers
Geometry of syzygies of sheaves on via interpolation and Bridgeland stability
Manuel Leal, Cesar Lozano Huerta, Tim Ryan
We show that the minimal free resolution of a general semi-stable sheaf on contains a subcomplex that determines an extremal ray of the cone of effective divisor…
Smooth Surfaces with Maximal Lines
Janet Page, Tim Ryan, Karen E. Smith
We prove that a smooth projective surface of degree in contains at most lines. We characterize the surfaces containing exactly lin…
Maximal skew sets of lines on a Hermitian surface and a modified Bron-Kerbosch algorithm
Anna Brosowsky, Haoyu Du, Madhav Krishna +3
In this paper, we study maximal sets of skew lines on Hermitian surfaces. We give a new algorithm to compute these sets and give some computational results for Hermitian surfaces o…
Geometry of Smooth Extremal Surfaces
Anna Brosowsky, Janet Page, Tim Ryan +1
We study the geometry of the smooth projective surfaces that are defined by Frobenius forms, a class of homogenous polynomials in prime characteristic recently shown to have minima…
Minimal free resolutions of sheaves on the projective plane and the stable base locus decomposition of their moduli spaces
Manuel Leal, César Lozano Huerta, Tim Ryan
The purpose of this paper is to incorporate minimal free resolutions into the study of the birational geometry of the moduli space of coherent sheaves on the plane with character $…
Irreducibility and singularities of some nested Hilbert schemes
Tim Ryan, Gregory Taylor
Let be a smooth projective surface over . We study the local and global geometry of the nested Hilbert scheme of points . In particular, we show th…
The geometry of Hilbert schemes of two points on projective space
Tim Ryan
In this paper, we give three bases for the cohomology groups of the Hilbert scheme of two points on projective space. Then, we use these bases to compute all effective and nef cone…
The sum of the Betti numbers of smooth Hilbert schemes
Joseph Donato, Monica Lewis, Tim Ryan +2
In this paper, we compute the sum of the Betti numbers for 6 of the 7 families of smooth Hilbert schemes over projective space.
Intrinsic and Extrinsic Approximation of Koopman Operators over Manifolds
Sai Tej Paruchuri, Jia Guo, Michael Kepler +4
This paper derives rates of convergence of certain approximations of the Koopman operators that are associated with discrete, deterministic, continuous semiflows on a complete metr…
Higher Codimension Cycles on the Hilbert Scheme of Three Points on the Projective Plane
Tim Ryan, Alexander Stathis
In this paper, we study the higher codimensional cycle structure of the Hilbert scheme of three points in the projective plane. In particular, we compute all Chern (and Segre) clas…
On the position of nodes of plane curves
Cesar Lozano Huerta, Tim Ryan
The Severi variety of plane curves of a given degree and exactly nodes admits a map to the Hilbert scheme of zero-dimensional subschemes of $\…
On the birational geometry of Hilbert schemes of points and Severi divisors
Cesar Lozano Huerta, Tim Ryan
We study the birational geometry of Hilbert schemes of points on non-minimal surfaces. In particular, we study the weak Lefschetz Principle in the context of birational geometry. W…
Nef cones of nested Hilbert schemes of points on surfaces
Tim Ryan, Ruijie Yang
Let be the projective plane, a Hirzebruch surface, or a general surface. In this paper, we study the birational geometry of various nested Hilbert schemes of points parame…
The Effective Cone of Moduli Spaces of Sheaves on a Smooth Quadric Surface
Tim Ryan
Let be a stable Chern character on , and let be the moduli space of Gieseker semistable sheaves on w…