The Mathematics Calendar
http://www.math.psu.edu/seminars/calendar.php
Seminars and special events the Pennsylvania State University Mathematics Department2014-09-02webmaster@math.psu.eduAn introduction to the use of algebraic geometry in Teichmuller dynamics, III. ATTENTION: the second lecture in this series will take place on THURSDAY AUGUST 28 3:30-6pm n Teichmuller dynamics,I
http://www.math.psu.edu/seminars/meeting.php?id=22799
Speaker(s): Alex Wright
2014-09-02T15:30:00Working Seminar: Dynamics and its Working Toolskatok_a@math.psu.eduhertz@math.psu.edukalinin@math.psu.eduEnergetic Derivation of Incompressible Euler and Navier-Stokes systems on an Evolving Hypersurface
http://www.math.psu.edu/seminars/meeting.php?id=24423
Speaker(s): Hajime Koba
In this talk, we consider fluid-flow on an evolving hypersurface. We apply our energetic variational approach to study the motion of incompressible inviscid and viscous flow on an evolving hypersurface. More precisely, we derive the incompressible Euler and Navier-Stokes equations on an evolving hypersurface by our energetic variational approach. Our results enable us to understand that the fluid-flow on an evolving hypersurface depend on both the curvature and the speed of an evolving hypersurface. This research relates to two phase flow
problems, geophysical fluid dynamics, and flows in fluid membranes. This is a joint work with Y. Giga (University of Tokyo) and C. Liu
(Penn State University).2014-09-03T15:30:00Complex Fluids Seminartxh35@math.psu.edufuy3@math.psu.eduSocial Pressure and Group Projects
http://www.math.psu.edu/seminars/meeting.php?id=23969
Speaker(s): Attendees
Research dating back to the 1950s has demonstrated how difficult it is for an individual to withstand social pressure. In some instances, social pressure can quell correct ideas in favor of incorrect ones. This week, we read an article describing this phenomenon (observed in the laboratory) and discuss strategies to guide students away from it.
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Asch, Solomon E. "Opinions and Social Pressure." <i>Scientific American</i> 193.5 (1955): 31-35. Web.2014-09-03T15:35:00Teaching Mathematics Discussion Group Seminarjamshidi@math.psu.eduSystems of conservation laws in one and two space dimensions (continue)
http://www.math.psu.edu/seminars/meeting.php?id=22148
Speaker(s): Yuxi Zheng
TBA2014-09-04T10:00:00Hyperbolic and Mixed Type PDEs Seminarzhang_t@math.psu.eduGalois groups of Mori polynomials, semistable curves and monodromy
http://www.math.psu.edu/seminars/meeting.php?id=21880
Speaker(s): Yuri Zarhin
We study the monodromy of a certain class of semistable hyperelliptic
curves that was introduced by Shigefumo Mori forty years ago. Using ideas
of Chris Hall, we prove that the corresponding monodromy groups are
(almost) ``as large as possible".2014-09-04T11:15:00Algebra and Number Theory Seminarrvaughan@math.psu.eduschwede@math.psu.edupapikian@math.psu.eduyee@math.psu.eduRamanujan, Fibonacci numbers, and Continued Fractions or Why I Took Zeckendorf's Theorem Along On My Last Trip To Canada
http://www.math.psu.edu/seminars/meeting.php?id=24008
Speaker(s): George Andrews
This talk focuses on the famous Indian genius, Ramanujan. One object will be to give some account of his meteoric rise and early death. We shall try to lead from some simple problems involving Fibonacci numbers to a discussion of some of Ramanujan's achievements including some things from his celebrated Lost Notebook.2014-09-04T13:15:00MASS Colloquiumdunlop@math.psu.eduvxs137@math.psu.eduWeighted entropy
http://www.math.psu.edu/seminars/meeting.php?id=22056
Speaker(s): Yuri Suhov
The entropy $h(X)=-\sum_ip_i\log\,p_i$ measures an expected amount of information/uncertainty related to a random variable $X$ taking values $i$ with probabilities $p_i$. The weighted entropy, $h^{\rm w}_\phi(X)$, is defined as $-\sum_i\phi (i)p_i\log\,p_i$ where $\phi (i)\geq 0$ is a weight function representing `utilities' of different values $i$ which we want to take into account. As in the case of a standard entropy, one can introduce conditional and relative weighted entropies; weighted differential entropies can also be defined. In this talk, I will discuss a recent progress in studying weighted entropies and their possible use in various areas.2014-09-05T15:35:00Probability and Financial Mathematics Seminardenker@math.psu.edumazzucat@math.psu.eduroyer@math.psu.edunistor@math.psu.eduanovikov@math.psu.eduEvolution of social instincts in within- and between-group conflicts
http://www.math.psu.edu/seminars/meeting.php?id=22711
Speaker(s): Sergey Gavrilets
I model the effects of within-group inequality on the evolution of social
instincts, i.e. genetically-based propensities and biases that affect the
behavior of individuals in social interactions. First, I consider competitive
within-group interactions. I identify a novel mechanism for the
evolutionary emergence of the "egalitarian syndrome" and leveling
coalitions in which one helps the weak against the strong bully. Second,
I study a collective action problem in between-group conflicts and show
how bullies can dialectically become "altruists". The mechanisms I describe
do not require genetic relatedness, reciprocity, reputation, or punishment.2014-09-08T14:30:00Computational and Applied Mathematics Colloquiumshaffer@math.psu.eduliu@math.psu.edufuw7@math.psu.eduPoisson and compound Poisson asymptotics in conventional and noncoventional setups
http://www.math.psu.edu/seminars/meeting.php?id=22822
Speaker(s): Yuri Kifer
During last 20-25 years a substantial attention was attracted to
the study of numbers of arrivals at small (shrinking) sets by trajectories of dynamical systems during the time intervals inversely proportional to the measure
of a set. It seems that the question was originated by Sinai in the framework
of the study of distributions of spacings between energy levels of quantum systems. Most of the papers dealt with the symbolic setup of a sequence space Ω with a shift invariant suciently fast mixing probability P where Pitskel,
Hirata and Denker showed that when P is a Gibbs shift invariant measure
then the numbers of arrivals to shrinking cylindrical neighborhoods of almost
all points are asymptotically Poisson distributed. More recently estimates for
Poisson approximations were obtained by Abadi and others while Haidn and
Vaienti obtained compound Poisson approximations for distributions of numbers of arrivals to shrinking cylindrical neighborhoods of some periodic points.
Asymptotics for arrivals to (geometric) balls considering distributions with respect to the SRB measure were studied by Collet, Dolgopyat, Freitas, Freitas,
Todd and others. Recently Poisson and compound Poisson limiting behavior in
the symbolic situation was extended to numbers of multiple recurrencies (nonconventional setup). In this talk we provide an essentially complete description
of possible limiting behaviors of distributions of numbers of multiple recurrencies to shrinking cylinders with respect to ψ-mixing shift invariant measures
which is partially new even for the widely studied single (conventional) recurrencies case (most of results are joint with my student Ariel Rapaport).2014-09-08T15:35:00Dynamical systems seminarkatok_s@math.psu.edusaz11@math.psu.edukatok_a@math.psu.eduhertz@math.psu.eduTBA
http://www.math.psu.edu/seminars/meeting.php?id=23659
Speaker(s): Brent Doiron
2014-09-09T13:00:00Theoretical Biology Seminarcpc16@math.psu.edutreluga@math.psu.eduRandomness, Riesz Capacity, Brownian Motion, and Complexity
http://www.math.psu.edu/seminars/meeting.php?id=22074
Speaker(s): Jason Rute
- Algorithmic randomness is a topic in computability theory which investigates which paths in a stochastic process behave randomly (with respect to all computable statistical tests).
- Riesz capacity is an important concept in potential theory and stochastic processes. It is used to estimate the probability that an n-dimensional Brownian motion hits a given set or is zero on a given set of times.
- The a priori complexity KM(x) is a measure of the computational complexity of a finite bit string x.
I will present the following result which connects these three subjects. The following are equivalent for t in (0,1].
1) t is Martin-Löf random with respect to 1/2-Reisz capacity.
2) t is a zero of some Martin-Löf random one-dimensional Brownian motion.
3) sum_n 2^{n/2 - KM(t[0,…,n-1])} < \infty where t[0,…,n-1] is the first n bits of the binary expansion of t.
This is joint work with Joseph Miller.2014-09-09T14:30:00Logic Seminarjmr71@math.psu.edusimpson@math.psu.edureimann@math.psu.eduTopological recurrence: variations and questions
http://www.math.psu.edu/seminars/meeting.php?id=23380
Speaker(s): Bryna Kra
I will give an overview of recurrence, focusing mainly on topological dynamical systems, describing combinatorial interpretations, relations between recurrence in different systems, and methods to formulate finite versions. This is based on joint work with Bernard Host and Alejandro Maass.2014-09-09T14:30:00Center for Dynamics and Geometry Colloquiumkatok_s@math.psu.edusaz11@math.psu.edukatok_a@math.psu.eduhertz@math.psu.edu