Results 11 to 20 of about 172 (97)
Rational points on even‐dimensional Fermat cubics
Abstract We show that even‐dimensional Fermat cubic hypersurfaces are rational over any field of characteristic not equal to three, by constructing explicit rational parameterizations with polynomials of low degree. As a byproduct of our rationality constructions, we obtain estimates for the number of their rational points over a number field and ...
Alex Massarenti
wiley +1 more source
Good Real Perturbations of Simple Corank One Map Germs From R3$\mathbb {R}^3$ to R3$\mathbb {R}^3$
ABSTRACT The existence of good real perturbations of map germs is one of the most interesting open questions in singularity theory. In this paper, we investigate this question for all simple corank one map germs from R3$\mathbb {R}^3$ to R3$\mathbb {R}^3$, we give a complete description of those that admit a good real perturbation.
A. J. Miranda, M. J. Saia, T. O. Souza
wiley +1 more source
Topological and geometric rigidity of nonnegatively curved submanifolds
Abstract We investigate the topology and geometry of compact submanifolds in space forms of nonnegative curvature satisfying a lower bound on the sectional curvature that depends only on the length of the mean curvature vector of the immersion. We show that this condition imposes strong constraints on either the topology or geometry of the submanifold.
Theodoros Vlachos
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bk$b^k$‐Algebroids and the variety of foliation jets
Abstract We introduce and classify singular foliations of bk+1$b^{k+1}$‐type, which formalize the properties of vector fields that are tangent to a submanifold W⊂M$W \subset M$ to order k$k$. When W$W$ is a hypersurface, these structures are Lie algebroids generalizing the bk+1$b^{k+1}$‐tangent bundles introduced by Scott.
Francis Bischoff +2 more
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Sharp restriction estimates for some degenerate higher codimensional quadratic surfaces
Abstract The Fourier restriction conjecture is a fundamental problem in harmonic analysis. In this paper, we investigate restriction estimates for degenerate higher codimensional quadratic surfaces and obtain sharp results for some types of degenerate cases.
Zhenbin Cao, Changxing Miao, Yixuan Pang
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Wasserstein rigidity over Rn$\mathbb {R}^n$ with smooth norms
Abstract We study p−Wasserstein$p-{\rm Wasserstein}$ spaces Wp(Rn,dN)$ \mathcal {W}_p(\mathbb {R}^n, d_N)$ over Rn$\mathbb {R}^n$ equipped with a norm metric dN$d_N$. We show that, if the norm is smooth enough, then the Wasserstein space is isometrically rigid whenever p≠2$p \ne 2$.
Zoltán M. Balogh +3 more
wiley +1 more source
ABSTRACT High‐frequency seismic wave descriptions are essential for fundamental geophysical applications, including earthquake hypocenter location, magnitude estimation, and traveltime–amplitude tomography. These descriptions rely on two coupled PDEs: the eikonal equation (governing traveltimes) and the transport equation (governing amplitudes ...
Ahmet Beyaz +2 more
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Refinements on higher order Weil–Oesterlé bounds via a Serre type argument
Abstract Weil's theorem gives the most standard bound on the maximum number of points Nq(g)$N_q(g)$ of a curve of genus g$g$ over a finite field Fq$\mathbb {F}_q$. This bound was improved by Ihara and Oesterlé for larger genus. A recent point of view allows one to recover these bounds by solving a sequence of semi‐definite programs, and the first two ...
Emmanuel Hallouin +2 more
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h$h$‐Function, Hilbert–Kunz density function and Frobenius–Poincaré function
Abstract Given ideals I,J$I,J$ of a noetherian local ring (R,m)$(R, \mathfrak {m})$ such that I+J$I+J$ is m$\mathfrak {m}$‐primary and a finitely generated R$R$‐module M$M$, we associate an invariant of (M,R,I,J)$(M,R,I,J)$ called the h$h$‐function.
Cheng Meng, Alapan Mukhopadhyay
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ABSTRACT Conformity of observed data with a postulated probability distribution is a fundamental problem of statistical modeling. Current tools for checking distributional conformity are often limited to univariate settings, with extensions to multivariate distributions facing challenges in interpretability and power.
Rasha Alsaadawi, Nitai D. Mukhopadhyay
wiley +1 more source

