RESEARCH STATEMENT TURGAY BAYRAKTAR

Size: px
Start display at page:

Download "RESEARCH STATEMENT TURGAY BAYRAKTAR"

Transcription

1 RESEARCH STATEMENT TURGAY BAYRAKTAR My research centers around complex analysis, complex geometry and probability theory. In one direction, I combine pluripotential theory with modern complex geometry techniques to study ergodic properties of holomorphic endomorphisms of complex manifolds and classification of varieties admitting dynamically interesting maps. From the probabilistic point of view, I am interested in stochastic properties of dynamical systems generated by random iteration of holomorphic endomorphisms. In the past few years, my focus has shifted toward random algebraic geometry, which explores local and global statistical properties of algebraic varieties when the coefficients in defining polynomials are considered as random variables. Below, I outline motivating sources behind my research projects, explain their achievements and describe future goals.. Universality of random zeros In the most general sense a random object of any kind means putting a probability measure on the set of objects and consider them as elements of a probability space. Instead of studying the individuals, one focuses on probabilities, averages and correlations. Here, we focus on global holomorphic sections H 0 (X, L n ) of tensor powers of a positive line bundle L X defined over a projective manifold X. For a fixed basis of H 0 (X, L n ), we consider linear combinations in which coefficients are non-degenerate i.i.d. real or complex random variables. The present geometric setting is a natural generalization of random polynomials with i.i.d. coefficients relative to a basis (eg. monomials, orthogonal polynomials). The basic questions are concerned with asymptotic distribution and correlations between zeros of generic, in the sense of probability, sequences of sections as the degree n. Motivating sources are coming from various areas: In complex analysis value distribution theory of polynomials or analytic functions is a classical topic but computable examples may not exhibit the typical behavior. One can study expected distribution of zeros, almost sure convergence of them etc. to understand the typical distribution. Moreover, random polynomials serve as a model for eigenfunctions of quantum chaotic Hamiltonians [BBL96]. Another motivation comes from algebraic geometry: If X = P k is the complex projective space and L = O() is the hyperplane bundle then holomorphic sections in H 0 (X, L n ) are essentially homogenous polynomials of degree n. In particular, simultaneous zero set Z s n,...,s k of k generic sections n defines an algebraic submanifold of codimension k and one would like to understand typical asymptotic behavior of such objects. For a smooth positively curved metric h on L X we denote its curvature form by ω h which is a positive smooth closed (, ) form on X and the induced volume form by dv := m! ωm h. Then there exists an associated scalar L2 -norm on the finite dimensional Hilbert space H 0 (X, L n ) and we denote the unit sphere with respect to this norm by SH 0 (X, L n ). Shiffman and Zelditch [SZ99, SZ08] studied asymptotic zero distribution of spherical ensemble SH 0 (X, L n ) endowed with U(d n )-invariant probability measure where d n = dim(h 0 (X, L n )). They proved that for a random sequence s n SH 0 (X, L n ) the Date: September 2, 205.

2 2 TURGAY BAYRAKTAR normalized zero currents n [Z n] converge almost surely to curvature form ω h as n. In particular, if the sections s n are chosen independently and at random then the zeros are uniformly distributed. In fact, for this example an implicit choice of an inner product on H 0 (X, L n ) forces zeros to distribute uniformly. More precisely, this ensemble can be equivalently obtained by fixing an orthonormal basis relative the L 2 -norm on H 0 (X, L n ) and letting the random coefficients to be i.i.d. standard complex Gaussians. Then several questions arise. Are zeros of random holomorphic sections always asymptoticly uniformly distributed? What are the geometric reasons behind all this that force random zeros asymptoticly equidistributed? Do non-gaussian ensembles of random holomorphic sections have the same asymptotic zero distribution as the Gaussian ensemble? The answer of the first two questions is related to the choice of the scalar inner product on H 0 (X, L n ) and the corresponding Bergman kernel asymptotics whereas for the last one, under mild assumptions on the distribution law of the coefficients we expect to have the asymptotic zero distribution to be independent of its choice. The universality phenomenon in the context of global holomorphic sections roughly says that as n asymptotic distribution of (appropriately normalized) zeros of random holomorphic sections should become independent of the choice of distribution of random coefficients. In [Bay3a, Bay4] I proved universality phenomenon (in any codimension) at macroscopic (global) scales for heavy tailed distributions. More recently [Bay5b], in complex dimension one it is proved that a mild log-integrability condition on the distribution of random coefficients is necessary and sufficient for universality of counting measures of zeros. In the sequel, I will describe details of these results and provide some examples to illustrate them. For a regular compact set K X and a continuous weight function Q : K R there is a naturally defined pluri-potential theoretic extremal function V K,Q. Let us denote equilibrium current by T K,Q := ω h + i π V K,Q. We remark that if K = X and Q 0 then T K,Q coincides with the curvature form ω h and we recover Shiffman-Zelditch setting. Another interesting example is that if K C is a regular compact set and Q 0, then T K,Q is the equilibrium measure of K which is the unique minimizer of the logarithmic energy functional ν log z w dν(z)dν(w) over all probability measures supported on K. For a fixed related orthonormal basis, we assume that random coefficients a j are i.i.d random variables whose distribution law P has a bounded density and logarithmically decaying tails i.e. P{a j C : log a j > R} = O(R ρ ) as R for some ρ > m +. Then it follows from Bertini s theorem that with probability one zero loci of random holomorphic sections intersect transversally. The following result describes asymptotic expected and almost sure distribution of normalized simultaneous zero sets. Theorem.. [Bay3a] Let X be a projective manifold and L X be a positive line bundle then for each k dim C X n k E[Z s n,...,sk n ] T k K,Q in the sense of currents as n. Moreover, if the ambient space X is complex homogeneous then almost surely n k [Z s n,...,s k n ] T k K,Q

3 in the sense of currents as n. RESEARCH STATEMENT 3 Recall that complex projective space P m is among the examples of complex homogenous manifolds. In particular, many classical random complex polynomial ensembles arise as a special case of Theorem.. For instance, if K = S is the unit circle in the complex plane then monomials form an ONB for polynomials ralative to the inner product f, g = f(ζ)g(ζ)dζ 2π S and our setting reduce to Kac random polynomials f n (z) = n j= a jz j the current of integration [Z fn ] = {z:f δ n(z)} z is the empirical measure of zeros and the equilibrium measure of S is the normalized angular measure 2π dθ. In particular, Theorem. implies that normalized zeros of Kac random polynomials of large degree tend to accumulate on the unit circle S and we recover a classical result due to Kac and Hammersley [Kac43, Ham56]. This ensemble of random polynomials has been studied extensively among others by [LO43, HN08, SV95] (see also [SZ03, Blo07, BS07, BL3] for more general random polynomial ensembles). In the univariate case, universality of zeros of random Kac polynomials was obtained by Ibragimov and Zaporozhets [IZ3] under a mild log-integrability condition. In a recent work [Bay5b], I generalized their result to the setting of random holomorphic sections. Theorem.2. [Bay5b] The logarithmic moment (.) E[log( + a j )] < if and only if { } (.2) P rob s n : lim n n V olω h 2m 2 (Z s n U) = V U = for every open set U X such that U has zero Lebesgue measure. Here, we denote the volume of the hypersurface Z sn in an open set U with respect to the volume form dv by V ol ω h 2m 2 (Z s n U) = ω m (m )! h and V U = T K,Q ω m Z sn U (m )! h. U In complex dimension one, V ol 2m 2 (Z sn U) becomes counting measure N n (s n, U) of zeros of s n in U. In particular, for an appropriate choice of the inner product on H 0 (X, L n ), Theorem.2 provides a necessary and sufficient condition for universality of elliptic polynomials (also known as SU(2) polynomials [BBL96]). Another interesting ensemble arising in [Bay5b] is Weyl polynomials. Recall that a random Weyl polynomial is of the from W n (z) = n j=0 a j n j j! z j. In [Bay5b], it is proved that condition (.) holds if and only if almost surely n N n(w n, U) λ(u D) n where λ is the Lebesgue measure on C and D denote the unit disc in the complex plane. Thus, we obtain an analogue of the circular law for random matrices (cf. [BC2]) in the present setting. For instance, Figures and 2 below illustrate the similar appearance of the zero distribution of a random Weyl polynomial of degree 2000 with i.i.d. Gaussian and Bernoulli (taking values ± with probability 2 ) random coefficients respectively.

4 4 TURGAY BAYRAKTAR Figure. Gaussian Figure 2. Bernoulli.. Random sparse polynomials. Recall that Newton polytope of a multivariable polynomial f(z) = a J z J is the convex hull of its support S f = {J Z m : a J 0}. It is well known that Newton polytope of a polynomial has crucial influence on its value distribution in particular on its zero set. A well-known theorem of Bernstein-Kouchnirenko asserts that the number of zeros of (a generic family of) m polynomials with Newton polytope P is m!v ol(p ). There is a vast literature on sparse polynomials (see eg. [HS95, Roj96, MR04, DGM3]) which are using methods of algebraic geometry to study zero distribution of systems of such polynomials. More recently, limiting zero distribution of Gaussian random sparse polynomials (induced from SU(m + ) polynomials) is studied by Shiffman and Zelditch [SZ04] from the complex analytic point-view. In [Bay4], I develop a pluri-potential theory to study asymptotic zero distribution of more general random sparse polynomial ensembles whose support are contained in dilates of a fixed integral polytope P as their degree grow. The universality phenomenon in the present setting is established by obtaining a quantitative localized version of Bernstein-Kouchnirenko Theorem [Bay4]..2. Work in progress. Another interesting topic related to random polynomials is the study of local statistics of their zero sets. In [ZZ0], Zelditch and Zeitouni proved that the normalized empirical measures of zeros of Gaussian random polynomials in one complex variable satisfies a large deviation principle (LDP). In a forthcoming project [Bayb], I consider hole probabilities for zeros of random polynomials and obtain moderate and large deviations estimates for non-gaussian ensembles. In particular, these results imply that there is no hope for LDP for heavy tailed distributions unless they have exponentially decaying tails. On the other hand, it is a questions that if LDP holds for distributions with exponentially decaying tails (eg. sub-gaussians). LDP for random polynomials with exponentially distributed coefficients was established in a more recent paper [GZ3]. I am interested in generalizing this LDP result to the setting of distributions with exponentially decaying tails. More generally, I intend to formulate a LDP in the case of random polynomials of several complex variables. Another universality form for zeros of random holomorphic sections is central limit theorem (CLT) for linear statistics of zeros. That is for a given smooth (m, m ) test form ϕ we consider the random variable [Z sn ], ϕ. In [Baya], we establish asymptotic normality of the random variables [Z sn ], ϕ E[ [Z sn ], ϕ ] V ar [Zsn ], ϕ for sufficiently smooth weight function Q. In particular, these results generalize [ST04, SZ0].

5 RESEARCH STATEMENT 5 2. Holomorphic Dynamics 2.. Ergodic and stochastic properties of holomorphic maps. A dynamical system, in the most general sense, is an object that evolves in time according to a fixed mathematical rule. In particular, a rational map f : P P of the Riemann sphere defines a discrete dynamical system by iteration. The dynamical study of rational maps of the Riemann sphere was initiated by Fatou and Julia in the early 900 s and has developed into a very rich and beautiful subject. There is a dichotomy between the Julia set where the dynamics is chaotic and the Fatou set on which the dynamics is predictable. A basic tool in the iteration theory of rational maps of P is Montel s theorem on normal families. In higher dimensions, however, the analogues of Montel s theorem do not have the appropriate adaptability. On the other hand, pluripotential theory reveals itself as a main tool in the multi-dimensional case. Following the successful study of rational maps of the Riemann sphere a great deal of research has gone into theory of iteration of rational maps in higher dimensions. Various categories of maps have been studied within the past two decades, particularly holomorphic maps of complex projective space P k (see [Sib99] and references therein). For a holomorphic endomorphism f : P k P k of algebraic degree d 2, its Green current T f is defined to be the weak limit of the sequence of smooth forms {d n (f n ) ω F S } where ω F S denotes Fubini-Study form on P k. Dynamical Green currents play a crucial role in the study of the iteration of holomorphic maps of P k. For instance, the support of the Green current is the Julia set. Moreover, T f has Hölder continuous quasi-potentials. Therefore, by Bedford-Taylor theory one can define the exterior powers of T f which are also dynamically interesting currents. In particular, the top degree self-intersection µ f = T f T f yields the unique f-invariant measure of maximal entropy [FS95, Sib99, BD0]. Statistical properties of µ f have also been extensively studied. By means of different methods it was proved that µ f satisfies Central Limit Theorem (CLT for short) for Hölder continuous observables ψ : P k R [CLB05, Dup0, DNS0] and for dsh observables (i.e. differences of quasi-plurisubharmonic functions) [DNS0]. Motivated by the deterministic case, in [Bay5a] I considered ergodic properties of composition of holomorphic endomorphisms f n f f 0 where f j s are independently chosen at random according to some probability distribution. More precisely, the set of rational endomorphisms f : P k P k with fixed algebraic degree d 2 can be identified with complex projective space P N for some N N and the set of holomorphic endomorphisms coincides with a Zariski open set H d P N. We fix a Borel probability measure P on P N and assume that a random rational map is holomorphic with probability one. By a random holomorphic endomorphism we mean a P N -valued random variable whose distribution law is P. For a sequence λ := (f 0, f,... ) of random holomorphic maps we denote F λ,n := f n... f f 0 and θ(λ) = (f, f 2,... ). Note that if m is a Dirac mass supported at f H d then the deterministic case emerges. On the other hand, an atomic measure of the form m = r r j= δ f j with f j H d gives rise to iterations of holomorphic maps in a finitely generated semi group. The next result indicates that almost surely the sequence of pullbacks of a smooth measure by a random sequence of holomorphic maps is equidistributed with a measure which depends only on the sequence: Theorem 2.. [Bay5a] If (2.) log dist(, P N \H d ) L m(p N )

6 6 TURGAY BAYRAKTAR then there exists a θ-invariant set A Hd N of probability one such that for almost every λ = (f 0, f,... ) A, the sequence of smooth forms {d pn Fλ,n ωk F S } converge weakly to a measure µ(λ) satisfying f0 (µ(θ(λ))) = d k µ(λ). Moreover, the measure µ(λ) has Hölder continuous potentials. The assumption (2.) holds in a quite general setting for instance, it holds any volume form on P N. Then we consider the expected value of the measure-valued random variable µ(λ) which is a probability measure whose action on a continuous function φ : Hd N Pk R is given by µ, φ := µ(λ), φ(λ, ) dp(λ) H N d where P is the product measure induced by P. The expected measure µ plays the role of the measure of maximal entropy defined in the deterministic case. Namely, µ is invariant under the natural skew product τ : H N d Pk H N d Pk τ(λ, x) = (θ(λ), f 0 (x)) i.e. τ µ = µ and the dynamical system (H N d Pk, µ, τ) is mixing and µ maximizes the mixed entropy introduced by Abramov and Rohlin [Bay5a, DT5]. Next, we turn out attention to statistical properties of the measure µ. The dynamical system (H N d Pk, µ, τ) has exponential decay of correlations for Hölder continuous and d.s.h. observables whenever the support of m is contained in H d [Bay5a]. The later result also allows us to obtain CLT for Hölder continuous and dsh observables. This generalizes the corresponding result of Dinh, Nguyen and Sibony [DNS0] proved for the deterministic case and establishes a universality result in the setting of random dynamical systems. Theorem 2.2. [Bay5a] If supp(m) H d then for every Hölder continuous function ψ : P k R which is not a coboundary and µ, ψ π = 0 there exists σ > 0 such that lim µ{ (λ, x) : n for every interval I R. n n j=0 ψ(f λ,j (x)) I } = 2πσ I exp( t2 2σ 2 )dt 2.2. Dynamics of meromorphic maps. Let f : P P be a rational map of degree d 2 and ν be any probability measure on P. A theorem of Brolin [Bro65], Lyubich [Lju83] and Freire-Lopez-Mañé [FLM83] asserts that the pre-images d n (f n ) ν converge weakly to the measure of maximal entropy µ f if and only if ν(e f ) = 0 where E f is an (possibly empty) exceptional set. In the graduate school, I considered the above equidistribution problem in a more general setting [Bay3c, Bay3b]. Let X be a compact Kähler manifold of complex dimension k and f : X X be a meromorphic endomorphism whose range contains an open set. In higher dimensions, meromorphic maps are not necessarily continuous, due to the possible existence of points of indeterminacy. The term map is loosely used here. Therefore, many natural concepts such as pull-back of a smooth form by f, topological (or metric) entropy etc. that are defined for smooth maps, require additional interpretation in the meromorphic setting. Although a meromorphic map is not smooth it induces a linear action on the cohomology f : H, (X, R) H, (X, R).

7 RESEARCH STATEMENT 7 Specifically, we focus on meromorphic maps with exponential growth on cohomology and study the existence of invariant currents representing the cohomology classes which are expanded under pull-back. Unlike the rational maps of P, there is no general existence theorem for the Green currents nor a complete characterization of the exceptional set of positive closed currents on compact Kähler manifolds. In this new setting, we replace smooth measures with smooth forms of bidegree (, ) and Dirac masses at a point with current of integrations along hypersurfaces. A natural question in dynamics is to provide necessary and sufficient conditions on a smooth form or more generally a positive closed current S such that the sequence of pull-backs {λ n f (f n ) S} n converges weakly to the Green current T f where λ f denotes the first dynamical degree of f. In [Bay2, Bay3c, Bay3b], I provided existence theorems for an f -invariant extremal current T f which has good convergence properties. For instance, in the algebraic case if the cohomology class of T f is the first Chern class of a finitely generated big line bundle then the Green current describes the limiting distribution of pre-images of zero divisors of global holomorphic sections [Bay3b]. In particular, if X = P k and L is the hyperplane bundle O() then we recover the corresponding result of Russakovskii and Shiffman [RS97] Automorphism groups of compact Kähler manifolds. A holomorphic automorphism of a compact Kähler manifold f : X X induces a linear action on the cohomology H (X, C) by pulling-back smooth forms. This provides a morphism Aut(X) GL(H (X, Z)) and we denote the image of this morphism by Aut(X). The notion of entropy is used to measure complexity of a dynamical system. Intuitively, the bigger entropy implies a richer dynamics. It follows from a theorem of Gromov and Yomdin that f Aut(X) has positive topological entropy if and only if one of the eigenvalues of f has modulus larger than one. In his works [Can99, Can0], Cantat proved that if X is a compact complex surface admitting a holomorphic automorphism with positive entropy then X is obtained from the complex projective plane P 2, a torus, a K3 surface or an Enriques surface by a finite sequence of point blow-ups. In particular, if X is a rational surface admitting an automorphism with positive entropy then it is obtained from P 2 by blowing up a finite sequence of at least ten points [Nag6]. Examples of rational surface automorphisms with positive entropy were given by McMullen [McM07], Bedford and Kim [BK0]; these examples are obtained from birational transformations f of the complex projective plane P 2 by a finite sequence of blow-ups that resolve all indeterminacies of f and f simultaneously. However, in higher dimensions it is not known that if one can obtain automorphisms with interesting dynamics on rational manifolds by blowing up along smooth centers. In a joint work with S. Cantat, we addressed this question in certain cases: Theorem 2.3. [BC3] Let X 0 be a smooth, connected, complex projective variety with Picard number (respectively compact Kähler manifold with h, (X 0 ) = ), m be a positive integer, and π i : X i+ X i, i = 0,..., m, be a sequence of blow-ups of smooth irreducible subvarieties of dimension at most r. If dim(x 0 ) > 2r + 2 then Aut(X m ) is a finite group. An immediate consequence is that every automorphism of such X m has zero topological entropy. In particular, if X is obtained from X 0 = P k with k 3 by blowing up a finite sequence of points then every holomorphic automorphism of X has zero topological entropy (see also [Bay3d]).

8 8 TURGAY BAYRAKTAR References [Baya] T. Bayraktar. Asymptotic normality of fluctuations of zeros of random holomorhic sections. in preparation. [Bayb] T. Bayraktar. Hole probabilities for zeros of random polynomials: Large and moderate deviations. in preparation. [Bay2] T. Bayraktar. Green currents for meromorphic maps of compact Kähler manifolds. PhD thesis, Indiana University, 202. [Bay3a] T. Bayraktar. Equidistribution of zeros of random holomorphic sections. to appear in Indiana Univ. Math. J., arxiv , 203. [Bay3b] T. Bayraktar. Equidistribution toward the green current in big cohomology classes. Internat. J. Math., 24(0):25pp, 203. [Bay3c] T. Bayraktar. Green currents for meromorphic maps of compact kähler manifolds. J. Geom. Anal., 23(2): , 203. [Bay3d] T. Bayraktar. On the automorphism group of rational manifolds. unpublished manuscript, arxiv:20.465, 203. [Bay4] T. Bayraktar. Zero distribution of random polynomials with fixed newton polytope. submitted to Trans. Amer. Math. Soc., arxiv , 204. [Bay5a] T. Bayraktar. Ergodic properties of random holomorphic endomorphisms of P k. Int. Math. Res. Not. IMRN, (4): , 205. [Bay5b] T. Bayraktar. Global universality of zeros of random polynomials. preprint, 205. [BC3] T. Bayraktar and S. Cantat. Constraints on automorphism groups of higher dimensional manifolds. J. Math. Anal. Appl., (405):209 23, 203. [BBL96] E. Bogomolny, O. Bohigas, and P. Leboeuf. Quantum chaotic dynamics and random polynomials. J. Statist. Phys., 85(5-6): , 996. [BC2] C. Bordenave and D. Chafaï. Around the circular law. Probab. Surv., 9: 89, 202. [BD0] Jean-Yves Briend and Julien Duval. Deux caractérisations de la mesure d équilibre d un endomorphisme de P k (C). Publ. Math. Inst. Hautes Études Sci., (93):45 59, 200. [BK0] E. Bedford and K. Kim. Continuous families of rational surface automorphisms with positive entropy. Math. Ann., 348(3): , 200. [BL3] T. Bloom and N. Levenberg. Random polynomials and pluripotential-theoretic extremal functions. preprint arxiv: , 203. [Blo07] T. Bloom. Random polynomials and (pluri)potential theory. Ann. Polon. Math., 9(2-3):3 4, [Bro65] H. Brolin. Invariant sets under iteration of rational functions. Ark. Mat., 6:03 44 (965), 965. [BS07] T. Bloom and B. Shiffman. Zeros of random polynomials on C m. Math. Res. Lett., 4(3): , [Can99] S. Cantat. Dynamique des automorphismes des surfaces projectives complexes. C. R. Acad. Sci. Paris Sér. I Math., 328(0):90 906, 999. [Can0] S. Cantat. Dynamique des automorphismes des surfaces K3. Acta Math., 87(): 57, 200. [CLB05] S. Cantat and S. Le Borgne. Théorème limite central pour les endomorphismes holomorphes et les correspondances modulaires. Int. Math. Res. Not., (56): , [DGM3] C. D Andrea, A. Galligo, and S. Martin. Quantitative equidistribution for the solutions of systems of sparse polynomial equations. American Journal of Mathematics, 203. [DNS0] T.C. Dinh, V.A. Nguyên, and N. Sibony. Exponential estimates for plurisubharmonic functions. Journal of Differential Geometry, 84(3): , 200. [DT5] Henry De Thélin. Endomorphismes pseudo-aléatoires dans les espaces projectifs II. J. Geom. Anal., 25(): , 205. [Dup0] C. Dupont. Bernoulli coding map and almost sure invariance principle for endomorphisms of P k. Probab. Theory Related Fields, 46(3-4): , 200. [FLM83] A. Freire, A. Lopes, and R. Mañé. An invariant measure for rational maps. Bol. Soc. Brasil. Mat., 4():45 62, 983. [FS95] J. E. Fornaess and N. Sibony. Complex dynamics in higher dimension. II. In Modern methods in complex analysis (Princeton, NJ, 992), volume 37 of Ann. of Math. Stud., pages Princeton Univ. Press, Princeton, NJ, 995. [GZ3] S. Ghosh and O. Zeitouni. Large deviations for zeros of random polynomials with iid exponential coefficients. to appear in IMRN arxiv:32.695, 203.

9 RESEARCH STATEMENT 9 [Ham56] J. M. Hammersley. The zeros of a random polynomial. In Proceedings of the Third Berkeley Symposium on Mathematical Statistics and Probability, , vol. II, pages 89, Berkeley and Los Angeles, 956. University of California Press. [HN08] C. P. Hughes and A. Nikeghbali. The zeros of random polynomials cluster uniformly near the unit circle. Compos. Math., 44(3): , [HS95] B. Huber and B. Sturmfels. A polyhedral method for solving sparse polynomial systems. Math. Comp., 64(22):54 555, 995. [IZ3] I. Ibragimov and D. Zaporozhets. On distribution of zeros of random polynomials in complex plane. In Prokhorov and Contemporary Probability Theory, pages Springer, 203. [Kac43] M. Kac. On the average number of real roots of a random algebraic equation. Bull. Amer. Math. Soc., 49:34 320, 943. [Lju83] M. Ju. Ljubich. Entropy properties of rational endomorphisms of the Riemann sphere. Ergodic Theory Dynam. Systems, 3(3):35 385, 983. [LO43] J. E. Littlewood and A. C. Offord. On the number of real roots of a random algebraic equation. III. Rec. Math. [Mat. Sbornik] N.S., 2(54): , 943. [McM07] C. T. McMullen. Dynamics on blowups of the projective plane. Publ. Math. Inst. Hautes Études Sci., (05):49 89, [MR04] G. Malajovich and J. M. Rojas. High probability analysis of the condition number of sparse polynomial systems. Theoret. Comput. Sci., 35(2-3): , [Nag6] M. Nagata. On rational surfaces. II. Mem. Coll. Sci. Univ. Kyoto Ser. A Math., 33:27 293, 960/96. [Roj96] J. M. Rojas. On the average number of real roots of certain random sparse polynomial systems. Lectures in Appl. Math., 32: , 996. [RS97] A. Russakovskii and B. Shiffman. Value distribution for sequences of rational mappings and complex dynamics. Indiana Univ. Math. J., 46(3): , 997. [Sib99] N. Sibony. Dynamique des applications rationnelles de P k. In Dynamique et géométrie complexes (Lyon, 997), volume 8 of Panor. Synthèses, pages ix x, xi xii, Soc. Math. France, Paris, 999. [ST04] M. Sodin and B. Tsirelson. Random complex zeroes. I. Asymptotic normality. Israel J. Math., 44:25 49, [SV95] L. A. Shepp and R. J. Vanderbei. The complex zeros of random polynomials. Trans. Amer. Math. Soc., 347(): , 995. [SZ99] B. Shiffman and S. Zelditch. Distribution of zeros of random and quantum chaotic sections of positive line bundles. Comm. Math. Phys., 200(3):66 683, 999. [SZ03] B. Shiffman and S. Zelditch. Equilibrium distribution of zeros of random polynomials. Int. Math. Res. Not., ():25 49, [SZ04] B. Shiffman and S. Zelditch. Random polynomials with prescribed Newton polytope. J. Amer. Math. Soc., 7():49 08 (electronic), [SZ08] B. Shiffman and S. Zelditch. Number variance of random zeros on complex manifolds. Geometric and Functional Analysis, 8(4): , [SZ0] B. Shiffman and S. Zelditch. Number variance of random zeros on complex manifolds, II: smooth statistics. Pure Appl. Math. Q., 6(4, Special Issue: In honor of Joseph J. Kohn. Part 2):45 67, 200. [ZZ0] O. Zeitouni and S. Zelditch. Large deviations of empirical measures of zeros of random polynomials. Int. Math. Res. Not. IMRN, (20): , 200. Mathematics Department, Syracuse University 3244 NY, USA address: tbayrakt@syr.edu

RESEARCH STATEMENT TURGAY BAYRAKTAR

RESEARCH STATEMENT TURGAY BAYRAKTAR RESEARCH STATEMENT TURGAY BAYRAKTAR My research focuses on complex dynamics in several variables. More precisely, I investigate the dynamical properties of meromorphic mappings of compact complex manifolds

More information

Progress in Several Complex Variables KIAS 2018

Progress in Several Complex Variables KIAS 2018 for Progress in Several Complex Variables KIAS 2018 Outline 1 for 2 3 super-potentials for 4 real for Let X be a real manifold of dimension n. Let 0 p n and k R +. D c := { C k (differential) (n p)-forms

More information

Zeros of Polynomials with Random Coefficients

Zeros of Polynomials with Random Coefficients Zeros of Polynomials with Random Coefficients Igor E. Pritsker Department of Mathematics, Oklahoma State University Stilwater, OK 74078 USA igor@math.okstate.edu Aaron M. Yeager Department of Mathematics,

More information

Dynamics in several complex variables: endomorphisms of projective spaces and polynomial-like mappings

Dynamics in several complex variables: endomorphisms of projective spaces and polynomial-like mappings arxiv:0810.0811v1 [math.ds] 5 Oct 2008 Dynamics in several complex variables: endomorphisms of projective spaces and polynomial-like mappings Tien-Cuong Dinh and Nessim Sibony 3 Abstract The emphasis

More information

Rigidity of harmonic measure

Rigidity of harmonic measure F U N D A M E N T A MATHEMATICAE 150 (1996) Rigidity of harmonic measure by I. P o p o v i c i and A. V o l b e r g (East Lansing, Mich.) Abstract. Let J be the Julia set of a conformal dynamics f. Provided

More information

Asymptotic Geometry. of polynomials. Steve Zelditch Department of Mathematics Johns Hopkins University. Joint Work with Pavel Bleher Bernie Shiffman

Asymptotic Geometry. of polynomials. Steve Zelditch Department of Mathematics Johns Hopkins University. Joint Work with Pavel Bleher Bernie Shiffman Asymptotic Geometry of polynomials Steve Zelditch Department of Mathematics Johns Hopkins University Joint Work with Pavel Bleher Bernie Shiffman 1 Statistical algebraic geometry We are interested in asymptotic

More information

arxiv: v1 [math.cv] 30 Jun 2008

arxiv: v1 [math.cv] 30 Jun 2008 EQUIDISTRIBUTION OF FEKETE POINTS ON COMPLEX MANIFOLDS arxiv:0807.0035v1 [math.cv] 30 Jun 2008 ROBERT BERMAN, SÉBASTIEN BOUCKSOM Abstract. We prove the several variable version of a classical equidistribution

More information

Bergman Kernels and Asymptotics of Polynomials II

Bergman Kernels and Asymptotics of Polynomials II Bergman Kernels and Asymptotics of Polynomials II Steve Zelditch Department of Mathematics Johns Hopkins University Joint work with B. Shiffman (Hopkins) 1 Our Topic A fundamental invariant associated

More information

Equidistribution towards the Green current for holomorphic maps

Equidistribution towards the Green current for holomorphic maps arxiv:math/0609686v1 [math.ds] 25 Sep 2006 Equidistribution towards the Green current for holomorphic maps Tien-Cuong Dinh and Nessim Sibony April 13, 2008 Abstract Let f be a non-invertible holomorphic

More information

Radial balanced metrics on the unit disk

Radial balanced metrics on the unit disk Radial balanced metrics on the unit disk Antonio Greco and Andrea Loi Dipartimento di Matematica e Informatica Università di Cagliari Via Ospedale 7, 0914 Cagliari Italy e-mail : greco@unica.it, loi@unica.it

More information

Zeros of lacunary random polynomials

Zeros of lacunary random polynomials Zeros of lacunary random polynomials Igor E. Pritsker Dedicated to Norm Levenberg on his 60th birthday Abstract We study the asymptotic distribution of zeros for the lacunary random polynomials. It is

More information

Tobias Holck Colding: Publications. 1. T.H. Colding and W.P. Minicozzi II, Dynamics of closed singularities, preprint.

Tobias Holck Colding: Publications. 1. T.H. Colding and W.P. Minicozzi II, Dynamics of closed singularities, preprint. Tobias Holck Colding: Publications 1. T.H. Colding and W.P. Minicozzi II, Dynamics of closed singularities, preprint. 2. T.H. Colding and W.P. Minicozzi II, Analytical properties for degenerate equations,

More information

KASS November 23, 10.00

KASS November 23, 10.00 KASS 2011 November 23, 10.00 Jacob Sznajdman (Göteborg): Invariants of analytic curves and the Briancon-Skoda theorem. Abstract: The Briancon-Skoda number of an analytic curve at a point p, is the smallest

More information

CANONICAL METRICS AND STABILITY OF PROJECTIVE VARIETIES

CANONICAL METRICS AND STABILITY OF PROJECTIVE VARIETIES CANONICAL METRICS AND STABILITY OF PROJECTIVE VARIETIES JULIUS ROSS This short survey aims to introduce some of the ideas and conjectures relating stability of projective varieties to the existence of

More information

Weak Mean Stability in Random Holomorphic Dynamical Systems Hiroki Sumi Graduate School of Human and Environmental Studies Kyoto University Japan

Weak Mean Stability in Random Holomorphic Dynamical Systems Hiroki Sumi Graduate School of Human and Environmental Studies Kyoto University Japan Weak Mean Stability in Random Holomorphic Dynamical Systems Hiroki Sumi Graduate School of Human and Environmental Studies Kyoto University Japan E-mail: sumi@math.h.kyoto-u.ac.jp http://www.math.h.kyoto-u.ac.jp/

More information

Equidistribution towards the Green current for holomorphic maps

Equidistribution towards the Green current for holomorphic maps Equidistribution towards the Green current for holomorphic maps Tien-Cuong Dinh and Nessim Sibony January 13, 2008 Abstract Let f be a non-invertible holomorphic endomorphism of a projective space and

More information

TitleOn manifolds with trivial logarithm. Citation Osaka Journal of Mathematics. 41(2)

TitleOn manifolds with trivial logarithm. Citation Osaka Journal of Mathematics. 41(2) TitleOn manifolds with trivial logarithm Author(s) Winkelmann, Jorg Citation Osaka Journal of Mathematics. 41(2) Issue 2004-06 Date Text Version publisher URL http://hdl.handle.net/11094/7844 DOI Rights

More information

NON-UNIVERSALITY OF THE NAZAROV-SODIN CONSTANT

NON-UNIVERSALITY OF THE NAZAROV-SODIN CONSTANT NON-UNIVERSALITY OF THE NAZAROV-SODIN CONSTANT Abstract. We prove that the Nazarov-Sodin constant, which up to a natural scaling gives the leading order growth for the expected number of nodal components

More information

ON THE DEFORMATION WITH CONSTANT MILNOR NUMBER AND NEWTON POLYHEDRON

ON THE DEFORMATION WITH CONSTANT MILNOR NUMBER AND NEWTON POLYHEDRON ON THE DEFORMATION WITH CONSTANT MILNOR NUMBER AND NEWTON POLYHEDRON OULD M ABDERRAHMANE Abstract- We show that every µ-constant family of isolated hypersurface singularities satisfying a nondegeneracy

More information

DYNAMICS OF RATIONAL MAPS: A CURRENT ON THE BIFURCATION LOCUS. Laura DeMarco 1 November 2000

DYNAMICS OF RATIONAL MAPS: A CURRENT ON THE BIFURCATION LOCUS. Laura DeMarco 1 November 2000 DYNAMICS OF RATIONAL MAPS: A CURRENT ON THE BIFURCATION LOCUS Laura DeMarco November 2000 Abstract. Let f λ : P P be a family of rational maps of degree d >, parametrized holomorphically by λ in a complex

More information

ON EMBEDDABLE 1-CONVEX SPACES

ON EMBEDDABLE 1-CONVEX SPACES Vâjâitu, V. Osaka J. Math. 38 (2001), 287 294 ON EMBEDDABLE 1-CONVEX SPACES VIOREL VÂJÂITU (Received May 31, 1999) 1. Introduction Throughout this paper all complex spaces are assumed to be reduced and

More information

Zeros of Random Analytic Functions

Zeros of Random Analytic Functions Zeros of Random Analytic Functions Zakhar Kabluchko University of Ulm September 3, 2013 Algebraic equations Consider a polynomial of degree n: P(x) = a n x n + a n 1 x n 1 +... + a 1 x + a 0. Here, a 0,

More information

Variations on Quantum Ergodic Theorems. Michael Taylor

Variations on Quantum Ergodic Theorems. Michael Taylor Notes available on my website, under Downloadable Lecture Notes 8. Seminar talks and AMS talks See also 4. Spectral theory 7. Quantum mechanics connections Basic quantization: a function on phase space

More information

The Yau-Tian-Donaldson Conjectuture for general polarizations

The Yau-Tian-Donaldson Conjectuture for general polarizations The Yau-Tian-Donaldson Conjectuture for general polarizations Toshiki Mabuchi, Osaka University 2015 Taipei Conference on Complex Geometry December 22, 2015 1. Introduction 2. Background materials Table

More information

COMPLEX PERSPECTIVE FOR THE PROJECTIVE HEAT MAP ACTING ON PENTAGONS SCOTT R. KASCHNER AND ROLAND K. W. ROEDER

COMPLEX PERSPECTIVE FOR THE PROJECTIVE HEAT MAP ACTING ON PENTAGONS SCOTT R. KASCHNER AND ROLAND K. W. ROEDER COMPLEX PERSPECTIVE FOR THE PROJECTIVE HEAT MAP ACTING ON PENTAGONS SCOTT R. KASCHNER AND ROLAND K. W. ROEDER Abstract. We place Schwartz s work on the real dynamics of the projective heat map H into the

More information

PULLING BACK COHOMOLOGY CLASSES AND DYNAMICAL DEGREES OF MONOMIAL MAPS. by Jan-Li Lin

PULLING BACK COHOMOLOGY CLASSES AND DYNAMICAL DEGREES OF MONOMIAL MAPS. by Jan-Li Lin Bull. Soc. math. France 140 (4), 2012, p. 533 549 PULLING BACK COHOMOLOGY CLASSES AND DYNAMICAL DEGREES OF MONOMIAL MAPS by Jan-Li Lin Abstract. We study the pullback maps on cohomology groups for equivariant

More information

ENOKI S INJECTIVITY THEOREM (PRIVATE NOTE) Contents 1. Preliminaries 1 2. Enoki s injectivity theorem 2 References 5

ENOKI S INJECTIVITY THEOREM (PRIVATE NOTE) Contents 1. Preliminaries 1 2. Enoki s injectivity theorem 2 References 5 ENOKI S INJECTIVITY THEOREM (PRIVATE NOTE) OSAMU FUJINO Contents 1. Preliminaries 1 2. Enoki s injectivity theorem 2 References 5 1. Preliminaries Let us recall the basic notion of the complex geometry.

More information

Tobias Holck Colding: Publications

Tobias Holck Colding: Publications Tobias Holck Colding: Publications [1] T.H. Colding and W.P. Minicozzi II, The singular set of mean curvature flow with generic singularities, submitted 2014. [2] T.H. Colding and W.P. Minicozzi II, Lojasiewicz

More information

THE GROUP OF AUTOMORPHISMS OF A REAL

THE GROUP OF AUTOMORPHISMS OF A REAL THE GROUP OF AUTOMORPHISMS OF A REAL RATIONAL SURFACE IS n-transitive JOHANNES HUISMAN AND FRÉDÉRIC MANGOLTE To Joost van Hamel in memoriam Abstract. Let X be a rational nonsingular compact connected real

More information

K-stability and Kähler metrics, I

K-stability and Kähler metrics, I K-stability and Kähler metrics, I Gang Tian Beijing University and Princeton University Let M be a Kähler manifold. This means that M be a complex manifold together with a Kähler metric ω. In local coordinates

More information

Note on the Chen-Lin Result with the Li-Zhang Method

Note on the Chen-Lin Result with the Li-Zhang Method J. Math. Sci. Univ. Tokyo 18 (2011), 429 439. Note on the Chen-Lin Result with the Li-Zhang Method By Samy Skander Bahoura Abstract. We give a new proof of the Chen-Lin result with the method of moving

More information

Logarithmic scaling of planar random walk s local times

Logarithmic scaling of planar random walk s local times Logarithmic scaling of planar random walk s local times Péter Nándori * and Zeyu Shen ** * Department of Mathematics, University of Maryland ** Courant Institute, New York University October 9, 2015 Abstract

More information

arxiv: v1 [math.cv] 15 Nov 2018

arxiv: v1 [math.cv] 15 Nov 2018 arxiv:1811.06438v1 [math.cv] 15 Nov 2018 AN EXTENSION THEOREM OF HOLOMORPHIC FUNCTIONS ON HYPERCONVEX DOMAINS SEUNGJAE LEE AND YOSHIKAZU NAGATA Abstract. Let n 3 and be a bounded domain in C n with a smooth

More information

Logarithmic functional and reciprocity laws

Logarithmic functional and reciprocity laws Contemporary Mathematics Volume 00, 1997 Logarithmic functional and reciprocity laws Askold Khovanskii Abstract. In this paper, we give a short survey of results related to the reciprocity laws over the

More information

BERGMAN KERNEL ON COMPACT KÄHLER MANIFOLDS

BERGMAN KERNEL ON COMPACT KÄHLER MANIFOLDS BERGMAN KERNEL ON COMPACT KÄHLER MANIFOLDS SHOO SETO Abstract. These are the notes to an expository talk I plan to give at MGSC on Kähler Geometry aimed for beginning graduate students in hopes to motivate

More information

Finding Roots of Any Polynomial by Random Relaxed Newton s Methods. Hiroki Sumi

Finding Roots of Any Polynomial by Random Relaxed Newton s Methods. Hiroki Sumi Finding Roots of Any Polynomial by Random Relaxed Newton s Methods Hiroki Sumi Graduate School of Human and Environmental Studies, Kyoto University, Japan E-mail: sumi@math.h.kyoto-u.ac.jp http://www.math.h.kyoto-u.ac.jp/

More information

AUTOMORPHISMS AND DYNAMICS: A LIST OF OPEN PROBLEMS

AUTOMORPHISMS AND DYNAMICS: A LIST OF OPEN PROBLEMS AUTOMORPHISMS AND DYNAMICS: A LIST OF OPEN PROBLEMS SERGE CANTAT Abstract. We survey a few results concerning groups of regular or birational transformations of projective varieties, with an emphasis on

More information

LECTURES ON THE CREMONA GROUP. Charles Favre. CNRS- CMLS École Polytechnique Palaiseau Cedex France

LECTURES ON THE CREMONA GROUP. Charles Favre. CNRS- CMLS École Polytechnique Palaiseau Cedex France LECTURES ON THE CREMONA GROUP Charles Favre CNRS- CMLS École Polytechnique 91128 Palaiseau Cedex France Abstract. These notes contain a summary of my lectures given in Luminy at KAWA2 in January 2011.

More information

Scalar curvature and the Thurston norm

Scalar curvature and the Thurston norm Scalar curvature and the Thurston norm P. B. Kronheimer 1 andt.s.mrowka 2 Harvard University, CAMBRIDGE MA 02138 Massachusetts Institute of Technology, CAMBRIDGE MA 02139 1. Introduction Let Y be a closed,

More information

Statistics of supersymmetric vacua in string/m theory

Statistics of supersymmetric vacua in string/m theory Statistics of supersymmetric vacua in string/m theory Steve Zelditch Department of Mathematics Johns Hopkins University Joint Work with Bernard Shiffman Mike Douglas 1 Supergravity theory An effective

More information

Takens embedding theorem for infinite-dimensional dynamical systems

Takens embedding theorem for infinite-dimensional dynamical systems Takens embedding theorem for infinite-dimensional dynamical systems James C. Robinson Mathematics Institute, University of Warwick, Coventry, CV4 7AL, U.K. E-mail: jcr@maths.warwick.ac.uk Abstract. Takens

More information

arxiv:alg-geom/ v1 29 Jul 1993

arxiv:alg-geom/ v1 29 Jul 1993 Hyperkähler embeddings and holomorphic symplectic geometry. Mikhail Verbitsky, verbit@math.harvard.edu arxiv:alg-geom/9307009v1 29 Jul 1993 0. ntroduction. n this paper we are studying complex analytic

More information

Holomorphic line bundles

Holomorphic line bundles Chapter 2 Holomorphic line bundles In the absence of non-constant holomorphic functions X! C on a compact complex manifold, we turn to the next best thing, holomorphic sections of line bundles (i.e., rank

More information

LIST OF PUBLICATIONS. Mu-Tao Wang. March 2017

LIST OF PUBLICATIONS. Mu-Tao Wang. March 2017 LIST OF PUBLICATIONS Mu-Tao Wang Publications March 2017 1. (with P.-K. Hung, J. Keller) Linear stability of Schwarzschild spacetime: the Cauchy problem of metric coefficients. arxiv: 1702.02843v2 2. (with

More information

How to count universes in string theory.

How to count universes in string theory. Random Complex Geometry, or How to count universes in string theory. Steve Zelditch Department of Mathematics Johns Hopkins University AMS meeting Atlanta Friday, January 7, 2005: 10: 05-10: 55 Joint work

More information

Expected zeros of random orthogonal polynomials on the real line

Expected zeros of random orthogonal polynomials on the real line ISSN: 889-3066 c 207 Universidad de Jaén Web site: jja.ujaen.es Jaen J. Approx. 9) 207), 24 Jaen Journal on Approximation Expected zeros of random orthogonal polynomials on the real line Igor E. Pritsker

More information

1. Plurisubharmonic functions and currents The first part of the homework studies some properties of PSH functions.

1. Plurisubharmonic functions and currents The first part of the homework studies some properties of PSH functions. MATH 263: PROBLEM SET 2: PSH FUNCTIONS, HORMANDER S ESTIMATES AND VANISHING THEOREMS 1. Plurisubharmonic functions and currents The first part of the homework studies some properties of PSH functions.

More information

HOLOMORPHIC MAPPINGS INTO SOME DOMAIN IN A COMPLEX NORMED SPACE. Tatsuhiro Honda. 1. Introduction

HOLOMORPHIC MAPPINGS INTO SOME DOMAIN IN A COMPLEX NORMED SPACE. Tatsuhiro Honda. 1. Introduction J. Korean Math. Soc. 41 (2004), No. 1, pp. 145 156 HOLOMORPHIC MAPPINGS INTO SOME DOMAIN IN A COMPLEX NORMED SPACE Tatsuhiro Honda Abstract. Let D 1, D 2 be convex domains in complex normed spaces E 1,

More information

Iteration of the rational function z 1/z and a Hausdorff moment sequence

Iteration of the rational function z 1/z and a Hausdorff moment sequence Iteration of the rational function z /z and a Hausdorff moment sequence Christian Berg University of Copenhagen, Institute of Mathematical Sciences Universitetsparken 5, DK-200 København Ø, Denmark Antonio

More information

The geometry of Landau-Ginzburg models

The geometry of Landau-Ginzburg models Motivation Toric degeneration Hodge theory CY3s The Geometry of Landau-Ginzburg Models January 19, 2016 Motivation Toric degeneration Hodge theory CY3s Plan of talk 1. Landau-Ginzburg models and mirror

More information

ABSOLUTE CONTINUITY OF FOLIATIONS

ABSOLUTE CONTINUITY OF FOLIATIONS ABSOLUTE CONTINUITY OF FOLIATIONS C. PUGH, M. VIANA, A. WILKINSON 1. Introduction In what follows, U is an open neighborhood in a compact Riemannian manifold M, and F is a local foliation of U. By this

More information

Eigenvalues and eigenfunctions of the Laplacian. Andrew Hassell

Eigenvalues and eigenfunctions of the Laplacian. Andrew Hassell Eigenvalues and eigenfunctions of the Laplacian Andrew Hassell 1 2 The setting In this talk I will consider the Laplace operator,, on various geometric spaces M. Here, M will be either a bounded Euclidean

More information

ALGEBRAIC HYPERBOLICITY OF THE VERY GENERAL QUINTIC SURFACE IN P 3

ALGEBRAIC HYPERBOLICITY OF THE VERY GENERAL QUINTIC SURFACE IN P 3 ALGEBRAIC HYPERBOLICITY OF THE VERY GENERAL QUINTIC SURFACE IN P 3 IZZET COSKUN AND ERIC RIEDL Abstract. We prove that a curve of degree dk on a very general surface of degree d 5 in P 3 has geometric

More information

David E. Barrett and Jeffrey Diller University of Michigan Indiana University

David E. Barrett and Jeffrey Diller University of Michigan Indiana University A NEW CONSTRUCTION OF RIEMANN SURFACES WITH CORONA David E. Barrett and Jeffrey Diller University of Michigan Indiana University 1. Introduction An open Riemann surface X is said to satisfy the corona

More information

On the simplest expression of the perturbed Moore Penrose metric generalized inverse

On the simplest expression of the perturbed Moore Penrose metric generalized inverse Annals of the University of Bucharest (mathematical series) 4 (LXII) (2013), 433 446 On the simplest expression of the perturbed Moore Penrose metric generalized inverse Jianbing Cao and Yifeng Xue Communicated

More information

RESEARCH INSTITUTE FOR MATHEMATICAL SCIENCES RIMS On self-intersection of singularity sets of fold maps. Tatsuro SHIMIZU.

RESEARCH INSTITUTE FOR MATHEMATICAL SCIENCES RIMS On self-intersection of singularity sets of fold maps. Tatsuro SHIMIZU. RIMS-1895 On self-intersection of singularity sets of fold maps By Tatsuro SHIMIZU November 2018 RESEARCH INSTITUTE FOR MATHEMATICAL SCIENCES KYOTO UNIVERSITY, Kyoto, Japan On self-intersection of singularity

More information

Torus actions and Ricci-flat metrics

Torus actions and Ricci-flat metrics Department of Mathematics, University of Aarhus November 2016 / Trondheim To Eldar Straume on his 70th birthday DFF - 6108-00358 Delzant HyperKähler G2 http://mscand.dk https://doi.org/10.7146/math.scand.a-12294

More information

Algebraic Curves and Riemann Surfaces

Algebraic Curves and Riemann Surfaces Algebraic Curves and Riemann Surfaces Rick Miranda Graduate Studies in Mathematics Volume 5 If American Mathematical Society Contents Preface xix Chapter I. Riemann Surfaces: Basic Definitions 1 1. Complex

More information

Large Deviations, Linear Statistics, and Scaling Limits for Mahler Ensemble of Complex Random Polynomials

Large Deviations, Linear Statistics, and Scaling Limits for Mahler Ensemble of Complex Random Polynomials Large Deviations, Linear Statistics, and Scaling Limits for Mahler Ensemble of Complex Random Polynomials Maxim L. Yattselev joint work with Christopher D. Sinclair International Conference on Approximation

More information

Multivariate polynomial approximation and convex bodies

Multivariate polynomial approximation and convex bodies Multivariate polynomial approximation and convex bodies Outline 1 Part I: Approximation by holomorphic polynomials in C d ; Oka-Weil and Bernstein-Walsh 2 Part 2: What is degree of a polynomial in C d,

More information

0.1 Complex Analogues 1

0.1 Complex Analogues 1 0.1 Complex Analogues 1 Abstract In complex geometry Kodaira s theorem tells us that on a Kähler manifold sufficiently high powers of positive line bundles admit global holomorphic sections. Donaldson

More information

From Random Polynomials to String Theory

From Random Polynomials to String Theory From Random Polynomials to String Theory Steve Zelditch Department of Mathematics Johns Hopkins University Madison, Wisconsin Friday, October 7, 4PM B239 Joint work with M. R. Douglas and B. Shiffman 1

More information

Partial Density Functions and Hele-Shaw Flow

Partial Density Functions and Hele-Shaw Flow Partial Density Functions and Hele-Shaw Flow Jackson Van Dyke University of California, Berkeley jayteeveedee@berkeley.edu August 14, 2017 Jackson Van Dyke (UCB) Partial Density Functions August 14, 2017

More information

arxiv: v2 [math.dg] 6 Nov 2014

arxiv: v2 [math.dg] 6 Nov 2014 A SHARP CUSP COUNT FOR COMPLEX HYPERBOLIC SURFACES AND RELATED RESULTS GABRIELE DI CERBO AND LUCA F. DI CERBO arxiv:1312.5368v2 [math.dg] 6 Nov 2014 Abstract. We derive a sharp cusp count for finite volume

More information

PERCOLATION AND COARSE CONFORMAL UNIFORMIZATION. 1. Introduction

PERCOLATION AND COARSE CONFORMAL UNIFORMIZATION. 1. Introduction PERCOLATION AND COARSE CONFORMAL UNIFORMIZATION ITAI BENJAMINI Abstract. We formulate conjectures regarding percolation on planar triangulations suggested by assuming (quasi) invariance under coarse conformal

More information

Chern numbers and Hilbert Modular Varieties

Chern numbers and Hilbert Modular Varieties Chern numbers and Hilbert Modular Varieties Dylan Attwell-Duval Department of Mathematics and Statistics McGill University Montreal, Quebec attwellduval@math.mcgill.ca April 9, 2011 A Topological Point

More information

Nodal Sets of High-Energy Arithmetic Random Waves

Nodal Sets of High-Energy Arithmetic Random Waves Nodal Sets of High-Energy Arithmetic Random Waves Maurizia Rossi UR Mathématiques, Université du Luxembourg Probabilistic Methods in Spectral Geometry and PDE Montréal August 22-26, 2016 M. Rossi (Université

More information

THE CREMONA GROUP: LECTURE 1

THE CREMONA GROUP: LECTURE 1 THE CREMONA GROUP: LECTURE 1 Birational maps of P n. A birational map from P n to P n is specified by an (n + 1)-tuple (f 0,..., f n ) of homogeneous polynomials of the same degree, which can be assumed

More information

Lecture 1. Toric Varieties: Basics

Lecture 1. Toric Varieties: Basics Lecture 1. Toric Varieties: Basics Taras Panov Lomonosov Moscow State University Summer School Current Developments in Geometry Novosibirsk, 27 August1 September 2018 Taras Panov (Moscow University) Lecture

More information

M ath. Res. Lett. 15 (2008), no. 2, c International Press 2008 SMOOTH HYPERSURFACE SECTIONS CONTAINING A GIVEN SUBSCHEME OVER A FINITE FIELD

M ath. Res. Lett. 15 (2008), no. 2, c International Press 2008 SMOOTH HYPERSURFACE SECTIONS CONTAINING A GIVEN SUBSCHEME OVER A FINITE FIELD M ath. Res. Lett. 15 2008), no. 2, 265 271 c International Press 2008 SMOOTH HYPERSURFACE SECTIONS CONTAINING A GIEN SUBSCHEME OER A FINITE FIELD Bjorn Poonen 1. Introduction Let F q be a finite field

More information

Chaos, Quantum Mechanics and Number Theory

Chaos, Quantum Mechanics and Number Theory Chaos, Quantum Mechanics and Number Theory Peter Sarnak Mahler Lectures 2011 Hamiltonian Mechanics (x, ξ) generalized coordinates: x space coordinate, ξ phase coordinate. H(x, ξ), Hamiltonian Hamilton

More information

Algebraic v.s. Analytic Point of View

Algebraic v.s. Analytic Point of View Algebraic v.s. Analytic Point of View Ziwen Zhu September 19, 2015 In this talk, we will compare 3 different yet similar objects of interest in algebraic and complex geometry, namely algebraic variety,

More information

Integrability and dynamical degree of periodic non-autonomous Lyness recurrences. Anna Cima

Integrability and dynamical degree of periodic non-autonomous Lyness recurrences. Anna Cima Proceedings of the International Workshop Future Directions in Difference Equations. June 13-17, 2011, Vigo, Spain. PAGES 77 84 Integrability and dynamical degree of periodic non-autonomous Lyness recurrences.

More information

SYMBOLIC DYNAMICS FOR HYPERBOLIC SYSTEMS. 1. Introduction (30min) We want to find simple models for uniformly hyperbolic systems, such as for:

SYMBOLIC DYNAMICS FOR HYPERBOLIC SYSTEMS. 1. Introduction (30min) We want to find simple models for uniformly hyperbolic systems, such as for: SYMBOLIC DYNAMICS FOR HYPERBOLIC SYSTEMS YURI LIMA 1. Introduction (30min) We want to find simple models for uniformly hyperbolic systems, such as for: [ ] 2 1 Hyperbolic toral automorphisms, e.g. f A

More information

Problems on Minkowski sums of convex lattice polytopes

Problems on Minkowski sums of convex lattice polytopes arxiv:08121418v1 [mathag] 8 Dec 2008 Problems on Minkowski sums of convex lattice polytopes Tadao Oda odatadao@mathtohokuacjp Abstract submitted at the Oberwolfach Conference Combinatorial Convexity and

More information

CONSIDERATION OF COMPACT MINIMAL SURFACES IN 4-DIMENSIONAL FLAT TORI IN TERMS OF DEGENERATE GAUSS MAP

CONSIDERATION OF COMPACT MINIMAL SURFACES IN 4-DIMENSIONAL FLAT TORI IN TERMS OF DEGENERATE GAUSS MAP CONSIDERATION OF COMPACT MINIMAL SURFACES IN 4-DIMENSIONAL FLAT TORI IN TERMS OF DEGENERATE GAUSS MAP TOSHIHIRO SHODA Abstract. In this paper, we study a compact minimal surface in a 4-dimensional flat

More information

Gaussian Fields and Percolation

Gaussian Fields and Percolation Gaussian Fields and Percolation Dmitry Beliaev Mathematical Institute University of Oxford RANDOM WAVES IN OXFORD 18 June 2018 Berry s conjecture In 1977 M. Berry conjectured that high energy eigenfunctions

More information

Changing sign solutions for the CR-Yamabe equation

Changing sign solutions for the CR-Yamabe equation Changing sign solutions for the CR-Yamabe equation Ali Maalaoui (1) & Vittorio Martino (2) Abstract In this paper we prove that the CR-Yamabe equation on the Heisenberg group has infinitely many changing

More information

Uniform K-stability of pairs

Uniform K-stability of pairs Uniform K-stability of pairs Gang Tian Peking University Let G = SL(N + 1, C) with two representations V, W over Q. For any v V\{0} and any one-parameter subgroup λ of G, we can associate a weight w λ

More information

On the Convergence of a Modified Kähler-Ricci Flow. 1 Introduction. Yuan Yuan

On the Convergence of a Modified Kähler-Ricci Flow. 1 Introduction. Yuan Yuan On the Convergence of a Modified Kähler-Ricci Flow Yuan Yuan Abstract We study the convergence of a modified Kähler-Ricci flow defined by Zhou Zhang. We show that the modified Kähler-Ricci flow converges

More information

A REMARK ON THE THEOREM OF OHSAWA-TAKEGOSHI

A REMARK ON THE THEOREM OF OHSAWA-TAKEGOSHI K. Diederich and E. Mazzilli Nagoya Math. J. Vol. 58 (2000), 85 89 A REMARK ON THE THEOREM OF OHSAWA-TAKEGOSHI KLAS DIEDERICH and EMMANUEL MAZZILLI. Introduction and main result If D C n is a pseudoconvex

More information

Some Open Problems Concerning Orthogonal Polynomials on Fractals and Related Questions

Some Open Problems Concerning Orthogonal Polynomials on Fractals and Related Questions Special issue dedicated to Annie Cuyt on the occasion of her 60th birthday, Volume 10 2017 Pages 13 17 Some Open Problems Concerning Orthogonal Polynomials on Fractals and Related Questions Gökalp Alpan

More information

MOTIVES OF SOME ACYCLIC VARIETIES

MOTIVES OF SOME ACYCLIC VARIETIES Homology, Homotopy and Applications, vol.??(?),??, pp.1 6 Introduction MOTIVES OF SOME ACYCLIC VARIETIES ARAVIND ASOK (communicated by Charles Weibel) Abstract We prove that the Voevodsky motive with Z-coefficients

More information

LONG TIME BEHAVIOUR OF PERIODIC STOCHASTIC FLOWS.

LONG TIME BEHAVIOUR OF PERIODIC STOCHASTIC FLOWS. LONG TIME BEHAVIOUR OF PERIODIC STOCHASTIC FLOWS. D. DOLGOPYAT, V. KALOSHIN AND L. KORALOV Abstract. We consider the evolution of a set carried by a space periodic incompressible stochastic flow in a Euclidean

More information

arxiv: v4 [math.dg] 7 Nov 2007

arxiv: v4 [math.dg] 7 Nov 2007 The Ricci iteration and its applications arxiv:0706.2777v4 [math.dg] 7 Nov 2007 Yanir A. Rubinstein Abstract. In this Note we introduce and study dynamical systems related to the Ricci operator on the

More information

Research Statement. Jayadev S. Athreya. November 7, 2005

Research Statement. Jayadev S. Athreya. November 7, 2005 Research Statement Jayadev S. Athreya November 7, 2005 1 Introduction My primary area of research is the study of dynamics on moduli spaces. The first part of my thesis is on the recurrence behavior of

More information

arxiv:math/ v2 [math.cv] 25 Mar 2008

arxiv:math/ v2 [math.cv] 25 Mar 2008 Characterization of the Unit Ball 1 arxiv:math/0412507v2 [math.cv] 25 Mar 2008 Characterization of the Unit Ball in C n Among Complex Manifolds of Dimension n A. V. Isaev We show that if the group of holomorphic

More information

BIG PICARD THEOREMS FOR HOLOMORPHIC MAPPINGS INTO THE COMPLEMENT OF 2n+1 MOVING HYPERSURFACES IN CP n

BIG PICARD THEOREMS FOR HOLOMORPHIC MAPPINGS INTO THE COMPLEMENT OF 2n+1 MOVING HYPERSURFACES IN CP n An. Şt. Univ. Ovidius Constanţa Vol. 18(1), 2010, 155 162 BIG PICARD THEOREMS FOR HOLOMORPHIC MAPPINGS INTO THE COMPLEMENT OF 2n+1 MOVING HYPERSURFACES IN CP n Nguyen Thi Thu Hang and Tran Van Tan Abstract

More information

A Picard type theorem for holomorphic curves

A Picard type theorem for holomorphic curves A Picard type theorem for holomorphic curves A. Eremenko Let P m be complex projective space of dimension m, π : C m+1 \{0} P m the standard projection and M P m a closed subset (with respect to the usual

More information

The Gaussian free field, Gibbs measures and NLS on planar domains

The Gaussian free field, Gibbs measures and NLS on planar domains The Gaussian free field, Gibbs measures and on planar domains N. Burq, joint with L. Thomann (Nantes) and N. Tzvetkov (Cergy) Université Paris Sud, Laboratoire de Mathématiques d Orsay, CNRS UMR 8628 LAGA,

More information

Second Julia sets of complex dynamical systems in C 2 computer visualization

Second Julia sets of complex dynamical systems in C 2 computer visualization Second Julia sets of complex dynamical systems in C 2 computer visualization Shigehiro Ushiki Graduate School of Human and Environmental Studies Kyoto University 0. Introduction As most researchers in

More information

One of the fundamental problems in differential geometry is to find metrics of constant curvature

One of the fundamental problems in differential geometry is to find metrics of constant curvature Chapter 2 REVIEW OF RICCI FLOW 2.1 THE RICCI FLOW One of the fundamental problems in differential geometry is to find metrics of constant curvature on Riemannian manifolds. The existence of such a metric

More information

COMPOSITION OPERATORS INDUCED BY SYMBOLS DEFINED ON A POLYDISK

COMPOSITION OPERATORS INDUCED BY SYMBOLS DEFINED ON A POLYDISK COMPOSITION OPERATORS INDUCED BY SYMBOLS DEFINED ON A POLYDISK MICHAEL STESSIN AND KEHE ZHU* ABSTRACT. Suppose ϕ is a holomorphic mapping from the polydisk D m into the polydisk D n, or from the polydisk

More information

THE VORTEX EQUATION ON AFFINE MANIFOLDS. 1. Introduction

THE VORTEX EQUATION ON AFFINE MANIFOLDS. 1. Introduction THE VORTEX EQUATION ON AFFINE MANIFOLDS INDRANIL BISWAS, JOHN LOFTIN, AND MATTHIAS STEMMLER Abstract. Let M be a compact connected special affine manifold equipped with an affine Gauduchon metric. We show

More information

arxiv: v1 [math.ag] 13 Mar 2019

arxiv: v1 [math.ag] 13 Mar 2019 THE CONSTRUCTION PROBLEM FOR HODGE NUMBERS MODULO AN INTEGER MATTHIAS PAULSEN AND STEFAN SCHREIEDER arxiv:1903.05430v1 [math.ag] 13 Mar 2019 Abstract. For any integer m 2 and any dimension n 1, we show

More information

SYMMETRY RESULTS FOR PERTURBED PROBLEMS AND RELATED QUESTIONS. Massimo Grosi Filomena Pacella S. L. Yadava. 1. Introduction

SYMMETRY RESULTS FOR PERTURBED PROBLEMS AND RELATED QUESTIONS. Massimo Grosi Filomena Pacella S. L. Yadava. 1. Introduction Topological Methods in Nonlinear Analysis Journal of the Juliusz Schauder Center Volume 21, 2003, 211 226 SYMMETRY RESULTS FOR PERTURBED PROBLEMS AND RELATED QUESTIONS Massimo Grosi Filomena Pacella S.

More information

An introduction to arithmetic groups. Lizhen Ji CMS, Zhejiang University Hangzhou , China & Dept of Math, Univ of Michigan Ann Arbor, MI 48109

An introduction to arithmetic groups. Lizhen Ji CMS, Zhejiang University Hangzhou , China & Dept of Math, Univ of Michigan Ann Arbor, MI 48109 An introduction to arithmetic groups Lizhen Ji CMS, Zhejiang University Hangzhou 310027, China & Dept of Math, Univ of Michigan Ann Arbor, MI 48109 June 27, 2006 Plan. 1. Examples of arithmetic groups

More information

Setting. Monochromatic random waves model the eigenfunctions of a quantization of a classically chaotic hamiltonian (M. Berry).

Setting. Monochromatic random waves model the eigenfunctions of a quantization of a classically chaotic hamiltonian (M. Berry). Nodal portrait Setting Monochromatic random waves model the eigenfunctions of a quantization of a classically chaotic hamiltonian (M. Berry). Random Fubini-Study ensembles are a model for random real algebraic

More information

ON A THEOREM OF CAMPANA AND PĂUN

ON A THEOREM OF CAMPANA AND PĂUN ON A THEOREM OF CAMPANA AND PĂUN CHRISTIAN SCHNELL Abstract. Let X be a smooth projective variety over the complex numbers, and X a reduced divisor with normal crossings. We present a slightly simplified

More information

SMOOTH OPTIMAL TRANSPORTATION ON HYPERBOLIC SPACE

SMOOTH OPTIMAL TRANSPORTATION ON HYPERBOLIC SPACE SMOOTH OPTIMAL TRANSPORTATION ON HYPERBOLIC SPACE JIAYONG LI A thesis completed in partial fulfilment of the requirement of Master of Science in Mathematics at University of Toronto. Copyright 2009 by

More information