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A bilinear inequality of Geba, Greenleaf, Iosevich, Palsson, and Sawyer for the Fourier transform is shown to be equivalent to a simpler linear inequality, and the range of exponents is extended. Related mixed-norm inequalities are…

Classical Analysis and ODEs · Mathematics 2015-12-11 Michael Christ

Let $X$ be a cubic fourfold that has only simple singularities and does not contain a plane. We prove that the Fano variety of lines on $X$ has the same analytic type of singularity as the Hilbert scheme of two points on a surface with only…

Algebraic Geometry · Mathematics 2018-04-03 Ryo Yamagishi

The F theorem states that, for a unitary three dimensional quantum field theory, the F quantity defined in terms of the partition function on a three sphere is positive, stationary at fixed point and decreases monotonically along a…

High Energy Physics - Theory · Physics 2016-04-26 Marika Taylor , William Woodhead

We present a smooth, complete toric threefold with no nontrivial nef line bundles. This is a counterexample to a recent conjecture of Fujino.

Algebraic Geometry · Mathematics 2007-05-23 Sam Payne

A $q$-analogue of a $t$-design is a set $S$ of subspaces (of dimension $k$) of a finite vector space $V$ over a field of order $q$ such that each $t$ subspace is contained in a constant $\lambda$ number of elements of $S$. The smallest…

Combinatorics · Mathematics 2017-10-10 John Bamberg , Ferdinand Ihringer , Jesse Lansdown , Gordon Royle

Four classes of three dimensional quadratic algebras of the type $\lsb Q_0 , Q_\pm \rsb$ $=$ $\pm Q_\pm$, $\lsb Q_+ , Q_- \rsb$ $=$ $aQ_0^2 + bQ_0 + c$, where $(a,b,c)$ are constants or central elements of the algebra, are constructed using…

Mathematical Physics · Physics 2009-11-07 V. Sunil Kumar , B. A. Bambah , R. Jagannathan

An inequality concerning ratios of gamma functions is proved. This answers a question of Guo and Qi (2003).

Classical Analysis and ODEs · Mathematics 2009-09-22 Yaming Yu

In this article we prove some strong vanishing theorems on K3 surfaces. As an aplication of them, we obtain higher syzygy results for K3 surfaces and Fano varieties.

alg-geom · Mathematics 2008-02-03 F. J. Gallego , B. P. Purnaprajna

In a previous study, we have discovered that nonlinear processes can be enhanced several orders of magnitude due to the path interference effects which are introduced by Fano resonances. Emergence of this phenomenon has been demonstrated…

Quantum Physics · Physics 2014-04-16 Mehmet Emre Tasgin

Fourier transform is applied to annular beams of simplified flat two-level geometry: bright outer ring with a darker core. The pattern of focal beam profile (i.e. far field) is calculated and characterized with respect of its intensity…

Optics · Physics 2009-04-14 D. N. Astadjov

The triadic description of General Relativity in three dimensions is known to be a BF theory. Diffeomorphisms, as symmetries, are easily re- covered on shell from the symmetries of BF theory. This note describes an explicit off-shell BV…

Mathematical Physics · Physics 2019-10-30 Alberto S. Cattaneo , Michele Schiavina , Iswaryaa Selliah

In the present work, we will develop a conformal inequality in the hyperbolic foliation context which is analogous to the conformal inequality in the classical time-constant foliation context. Then as an application, we will apply this a…

Analysis of PDEs · Mathematics 2017-11-03 Yue Ma , Hongjing Huang

We compute the facets of the effective cones of divisors on the blow-up of P^3 in up to five lines in general position. We prove that up to six lines these threefolds are weak Fano and hence Mori Dream Spaces.

Algebraic Geometry · Mathematics 2016-04-21 Olivia Dumitrescu , Elisa Postinghel , Stefano Urbinati

We generalize the equivariant intermediate Jacobian torsor obstruction over $\mathbb{C}$ to algebraically closed fields of characteristic zero. It is an obstruction to the (projective) linearizability problem of finite group actions on…

Algebraic Geometry · Mathematics 2026-01-13 Shuto Abe

Non-alternating Hamiltonian Lie algebras in three variables over a perfect field of characteristic 2 are considered. A classification of non-alternating Hamiltonian forms over an algebra of divided powers in three variables and of the…

Rings and Algebras · Mathematics 2021-01-05 A. V. Kondrateva

In a photoionization spectrum in which there is no excitation of the discrete states, but only the underlying continuum, we have observed resonances which appear as symmetric peaks, not the commonly expected window resonances. Furthermore,…

Condensed Matter · Physics 2009-11-10 U. Eichmann , T. F. Gallagher , R. M. Konik

A powerful tool of investigation of Fano varieties is provided by exceptional collections in their derived categories. Proving the fullness of such a collection is generally a nontrvial problem, usually solved on a case-by-case basis, with…

Algebraic Geometry · Mathematics 2021-03-30 Barbara Bolognese , Domenico Fiorenza

We show that the presence of a side-attached state strongly modifies the transmission through a one-dimensional double-barrier system in the window of wavevectors around the Fano antiresonance. Specifically, the interplay between the Fano…

Mesoscale and Nanoscale Physics · Physics 2020-07-01 J. Klier , I. V. Krainov , A. P. Dmitriev , I. V. Gornyi

For a positive integer $n$, an $n$-sided polygon lying on a circular arc or, shortly, an $n$-fan is a sequence of $n+1$ points on a circle going counterclockwise such that the "total rotation" $\delta$ from the first point to the last one…

Algebraic Geometry · Mathematics 2017-10-25 Delbrin Ahmed , Gábor Czédli , Eszter K. Horváth

This paper studies the defect of terminal Gorenstein Fano 3 folds. I determine a bound on the defect of terminal Gorenstein Fano 3-folds of Picard rank 1 that do not contain a plane. I give a general bound for quartic 3-folds and indicate…

Algebraic Geometry · Mathematics 2009-08-24 Anne-Sophie Kaloghiros