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This note intends to demonstrate how to discuss scalar curvature functions' admissibility on bundles by directly applying some of the Kazdan--Warner results. Proofs of the concept include determining which functions are realizable as scalar…

Differential Geometry · Mathematics 2023-05-16 Leonardo Francisco Cavenaghi , Llohann Dallagnol Sperança

We provide a formula for every Schur coefficient in the chromatic symmetric function of a graph in terms of special rim hook tabloids. This formula is useful in confirming the non-Schur positivity of the chromatic symmetric function of a…

Combinatorics · Mathematics 2020-01-17 David G. L. Wang , Monica M. Y. Wang

We establish an equivariant quantum Giambelli formula for partial flag varieties. The answer is given in terms of a specialization of universal double Schubert polynomials. Along the way, we give new proofs of the presentation of the…

Algebraic Geometry · Mathematics 2015-06-10 Dave Anderson , Linda Chen

We prove a new signed elementary symmetric function expansion of the chromatic quasisymmetric function of any natural unit interval graph. We then use a sign-reversing involution to prove a new combinatorial formula for K-chains, which are…

Combinatorics · Mathematics 2024-05-09 Foster Tom

We prove a formula for the ${\mathbb S}_n$-equivariant Euler characteristic of the moduli space of graphs $\mathcal{MG}_{g,n}$. Moreover, we prove that the rational ${\mathbb S}_n$-invariant cohomology of $\mathcal{MG}_{g,n}$ stabilizes for…

Algebraic Topology · Mathematics 2025-11-05 Michael Borinsky , Jos Vermaseren

We prove two conjectures of Shareshian and Wachs about Eulerian quasisymmetric functions and polynomials. The first states that the cycle type Eulerian quasisymmetric function $Q_{\lambda,j}$ is Schur-positive, and moreover that the…

Combinatorics · Mathematics 2011-11-10 Anthony Henderson , Michelle L. Wachs

The higher characteristics w_m(G) for a finite abstract simplicial complex G are topological invariants that satisfy k-point Green function identities and can be computed in terms of Euler characteristic in the case of closed manifolds,…

Combinatorics · Mathematics 2023-02-07 Oliver Knill

We prove some general results on the T-equivariant K-theory K_T(G/P) of the flag variety G/P, where G is a semisimple complex algebraic group, P is a parabolic subgroup and T$ is a maximal torus contained in P. In particular, we make a…

Algebraic Geometry · Mathematics 2008-01-21 William Graham , Shrawan Kumar

We study the operational bivariant theory associated to the covariant theory of Grothendieck groups of coherent sheaves, and prove that it has many geometric properties analogous to those of operational Chow theory. This operational…

Algebraic Geometry · Mathematics 2015-06-10 Dave Anderson , Sam Payne

K-theoretic Donaldson invariants are holomorphic Euler characteristics of determinant line bundles on moduli spaces of rank 2 sheaves on surfaces. We develop an algorithm which determines the generating functions of K-theoretic Donaldson…

Algebraic Geometry · Mathematics 2016-09-26 Lothar Göttsche

Chen proposed a conjecture on the log-concavity of the generating function for the symmetric group with respect to the length of longest increasing subsequences of permutations. Motivated by Chen's log-concavity conjecture, B\'{o}na,…

Combinatorics · Mathematics 2017-03-21 Alice L. L. Gao , Matthew H. Y. Xie , Arthur L. B. Yang

We generalize several classical results about Schur functions to the family of cylindric Schur functions. First, we give a combinatorial proof of a Murnaghan--Nakayama formula for expanding cylindric Schur functions in the power-sum basis.…

Combinatorics · Mathematics 2023-11-14 Per Alexandersson , Ezgi Kantarci Oğuz

We study two classes of permutations intimately related to the visual proof of Spitzer's lemma and Huq's generalization of the Chung-Feller theorem. Both classes of permutations are counted by the Fuss-Catalan numbers. The study of one…

Combinatorics · Mathematics 2023-10-11 Richard Ehrenborg , Gábor Hetyei , Margaret Readdy

We characterize $k$-hyponormality and quadratic hyponormality of powers of weighted shifts using Schur product techniques.

Functional Analysis · Mathematics 2007-05-23 Raul E. Curto , Sang Soo Park

We generalize the notion of Thom polynomials from singularities of maps between two complex manifolds to invariant cones in representations, and collections of vector bundles. We prove that the generalized Thom polynomials, expanded in the…

Algebraic Geometry · Mathematics 2007-09-11 Piotr Pragacz , Andrzej Weber

Let $k$ be an algebraically closed field of characteristic $p>0$ and let $\ell$ be another prime number. O. Gabber and F. Loeser proved that for any algebraic torus $T$ over $k$ and any perverse $\ell$-adic sheaf $\calF$ on $T$ the Euler…

Algebraic Geometry · Mathematics 2007-05-23 Alexander Braverman

We study the torus-equivariant homology $H_*^T(\mathrm{Gr}_G)$ of the affine Grassmannian $\mathrm{Gr}_G$, where $G=\mathrm{Sp}_{2n}(\mathbb{C})$ is the symplectic group. This homology admits a natural ring structure and a Schubert basis,…

Representation Theory · Mathematics 2025-11-27 Takeshi Ikeda , Shinsuke Iwao , Mark Shimozono

We derive several identities involving Ikeda and Naruse's $K$-theoretic Schur $P$- and $Q$-functions. Our main result is a formula conjectured by Lewis and the second author which expands each $K$-theoretic Schur $Q$-function in terms of…

Combinatorics · Mathematics 2024-02-01 Yu-Cheng Chiu , Eric Marberg

Let $\mathbb{N}$ denote the set of non-negative integers. Haglund, Wilson, and the second author have conjectured that the coefficient of any Schur function $s_\lambda[X]$ in $\Delta_{e_k} e_n[X]$ is a polynomial in $\mathbb{N}[q,t]$. We…

Combinatorics · Mathematics 2017-10-11 Dun Qiu , Jeffrey B. Remmel , Emily Sergel , Guoce Xin

We study sections of the relative Picard bundle of a family of curves of genus $g \geq 2$ through the rank of the associated normal function. Using Griffiths' formula for the infinitesimal invariant and higher Schiffer variations, we…

Algebraic Geometry · Mathematics 2026-02-17 Lorenzo Fassina , Gian Pietro Pirola