collaborators

6 papers

math.AG2026

The rank of the permanent tensor is sixteen

Jong In Han, Jeyoung Song

In this paper, we show that the tensor rank of the permanent tensor is at least over and its subfields, which matches the known upper bound. The $5\ti…

math.AG2026

The Eisenbud-Goto conjecture for projectively normal varieties with mild singularities

Jong In Han

For a nondegenerate projective variety , the Eisenbud-Goto conjecture asserts that . Despite the existence of…

math.AG2025

Hierarchical structure of graded Betti numbers in the quadratic strand

Jong In Han, Sijong Kwak, Wanseok Lee

The classical results, initiated by Castelnuovo and Fano and later refined by Eisenbud and Harris, provide several upper bounds on the number of quadrics defining a nondegenerate p…

math.AG2025

Characterization of projective varieties beyond varieties of minimal degree and del Pezzo varieties

Jong In Han, Sijong Kwak, Euisung Park

Varieties of minimal degree and del Pezzo varieties are basic objects in projective algebraic geometry. Those varieties have been characterized and classified for a long time in ma…

math.AG2025

Surface counterexamples to the Eisenbud-Goto conjecture

Jong In Han, Sijong Kwak

It is well known that the Eisenbud-Goto regularity conjecture is true for arithmetically Cohen-Macaulay varieties, projective curves, smooth surfaces, smooth threefolds in $\mathbb…

math.AG2025

On quadratic persistence and Pythagoras numbers of totally real projective varieties

Jong In Han, Jaewoo Jung, Euisung Park

In this paper, we study the relationship between quadratic persistence and the Pythagoras number of totally real projective varieties. Building upon the foundational work of Blekhe…