比利时vs摩洛哥足彩
,
university of california san diego
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final defense
shubham sinha
uc san diego
numerical invariants of quot scheme of curves
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apm 7321
apm 7321
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比利时vs摩洛哥足彩
,
university of california san diego
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math 248 seminar in real analysis
prof. koffi enakoutsa
ucla
the morrey conjecture: examining an unsolved problem with numerical simulations
abstract:
the morrey conjecture pertains to the properties of quasi-convexity and rank-one convexity in functions, where the former implies the latter, but the converse relationship is not yet established. while sverak has proven the conjecture in three dimensions, it remains unresolved in the two-dimensional case. analyzing these properties analytically is a formidable task, particularly for vector-valued functions. consequently, to investigate the validity of the morrey conjecture, we conducted numerical simulations using a set of example functions by dacorogna and marcellini. based on our results, the morrey conjecture appears to hold true for these functions.
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apm 7321
apm 7321
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比利时vs摩洛哥足彩
,
university of california san diego
****************************
steven strogatz: mathematician and bestselling author
abstract:
when steven strogatz wrote a 15-part series on the elements of math for the new york times, to his surprise — and his editor's — each piece climbed the most emailed list and elicited hundreds of appreciative comments. in this talk steve will describe his adventures in bringing math to the masses, and will reflect on what works… and what doesn’t.
steven strogatz is the jacob gould schurman professor of applied mathematics at cornell university. he works on nonlinear dynamics with applications to physics, biology, and the social sciences. his latest book, infinite powers, was a new york times bestseller and was shortlisted for the 2019 royal society science book prize.
presented by the uc san diego research communications program and supported by a grant from the gordon and betty moore foundation.
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virtual, please register at researchcommunications.ucsd.edu
virtual, please register at researchcommunications.ucsd.edu
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比利时vs摩洛哥足彩
,
university of california san diego
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combinatorics seminar (math 269)
brendon rhoades
ucsd
the superspace coinvariant ring
abstract:
the classical coinvariant ring $r_n$ is obtained from the polynomial ring $\mathbb{c}[x_1, \dots, x_n]$ by quotienting by the ideal $i_n$ generated by symmetric polynomials with vanishing constant terms. the {\em superspace coinvariant ring} $sr_n$ is obtained analogously, but starting with the ring $\omega_n$ of regular differential forms on $n$-space. we describe the bigraded hilbert series of $sr_n$ in terms of ordered set partitions and give an `operator theorem' which describes the harmonic space attached to $sr_n$. this proves conjectures of n. bergeron, li, machacek, sulzgruber, swanson, wallach, and zabrocki. this talk is based on joint work with andy wilson.
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apm 6402 (halkin room)
apm 6402 (halkin room)
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比利时vs摩洛哥足彩
,
university of california san diego
****************************
math 292
zhouli xu
ucla
equivariant dunn additivity
abstract:
the boardman-vogt tensor product of operads encodes the notion of interchanging algebraic structures. a classic result of dunn tells us that the tensor product of two little cube operads is equivalent to a little cube operad with the dimensions added together. as models for $\mathbb{e}_k$-operads, this reflects a defining property of these operads.
in this talk, we will explore some equivariant generalizations to dunn’s additivity. along the way, we will play with little star-shaped operads, question if we really need group representations for equivariant operads, and learn to love (and hate) the tensor product.
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apm 7321
apm 7321
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比利时vs摩洛哥足彩
,
university of california san diego
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math 278c: optimization and data science
prof. suhan zhong
taxus a&m university
chance constrained optimization with polynomial perturbation
abstract:
we study a robust approximation method for solving a class of chance constrained optimization problems. the constraints are assumed to be polynomial in the random vector. a semidefinite relaxation algorithm is proposed for solving this kind of problem. its asymptotic and finite convergence are proven under some mild assumptions.
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apm 7321
apm 7321
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比利时vs摩洛哥足彩
,
university of california san diego
****************************
math 211b - group actions seminar
timothée bénard
centre for mathematical sciences, university of cambridge
random walks with bounded first moment on finite volume spaces
abstract:
we consider a finite volume homogeneous space endowed with a random walk whose driving measure is zariski-dense. in the case where jumps have finite exponential moment, eskin-margulis and benoist-quint established recurrence properties for such a walk. i will explain how their results can be extended to walks with finite first moment. the key is to make sense of the following claim: "the walk in a cusp goes down faster that some iid markov chain on r with negative mean". joint work with n. de saxcé.
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zoom id 967 4109 3409 (password: dynamics)
zoom id 967 4109 3409 (password: dynamics)
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比利时vs摩洛哥足彩
,
university of california san diego
****************************
math 288 - probability seminar
benson au
uc berkeley
outlying eigenvalues and their eigenvectors
abstract:
imagine passing a signal $v$ through a noisy channel, where $v \in \mathbb{c}^n$ is a deterministic unit vector. we assume that the recipient observes a corrupted version of the signal in the form of $\theta vv^* + m$, where $\theta \in \mathbb{r}$ is the strength of the signal and $m$ is a random hermitian $n \times n$ matrix representing the noise. we consider two questions:
- (detection) is it possible for the recipient to conclude that a signal has been passed based on the observation?
- (recovery) if so, is it possible for the recipient to recover the signal
for rotationally invariant noise, benaych-georges and nadakuditi answered the detection question in terms of the outlying eigenvalues and the recovery question in terms of the corresponding eigenvectors. their proof crucially relies on the fact that the eigenvectors of a rotationally invariant ensemble are haar distributed (in particular, delocalized).
we consider a general class of noise that includes non mean-field models such as random band matrices in regimes where the eigenvectors are known to be localized. in contrast to the usual approach to outliers via the resolvent, our analysis relies on moment method calculations for general vector states and a seemingly innocuous isotropic global law.
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apm 6311 with live streaming via zoom. contact poagarwal@ucsd.edu for zoom info
apm 6311 with live streaming via zoom. contact poagarwal@ucsd.edu for zoom info
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比利时vs摩洛哥足彩
,
university of california san diego
****************************
math 258
hongyi shen
ucsd
deformations of the scalar curvature and the mean curvature
abstract:
on a compact manifold with boundary, the map consisting of the scalar curvature in the interior and the mean curvature on the boundary is a local surjection at generic metrics. we prove that this result may be localized to compact subdomains in an arbitrary riemannian manifold with boundary, as motivated by an attempt to generalize the riemannian penrose inequality in dimension 8. this result is a generalization of corvino's result about localized scalar curvature deformations; however, the existence part needs to be handled delicately since the problem is non-variational. for non-generic cases, we give a classification theorem for domains in space forms and schwarzschild manifolds, and show the connection with positive mass theorems.
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apm 5829
apm 5829
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