A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.
Let n be a positive integer, and let ℓ>1 be square-free odd. We classify the set of equivariant homeomorphism classes of free Cℓ-actions on the product S1×Sn of spheres, up to indeterminacy bounded in ℓ. The description is expressed in terms of number theory. The techniques are various appl…
Let d be a positive square-free integer ≡3(mod4) such that there is no invariant of the ideal class group Q[−d] which is divisible by 4. We prove an asymptotic formula for the number of immersed totally geodesic surfaces in Γ−d\H3 having area less t…
In this paper, we compute the covolume of the group of units of the quadratic form f_d^n(x) = x_1^2 + x_2^2 + . . . + x_n^2 - d x_{n+1}^2 with d an odd, positive, square-free integer. Mcleod has determined the hyperbolic Coxeter fundamental domain of the reflection subgroup of the group of units of the quadratic form f…
The cosmetic crossing conjecture (also known as the "nugatory crossing conjecture") asserts that the only crossing changes that preserve the oriented isotopy class of a knot in the 3-sphere are nugatory. We use the Dehn surgery characterization of the unknot to prove this conjecture for knots in integer homology sphere…
We study a subset of square free positive braids and we give a few algebraic characterizations of them and one geometric characterization: the set of positive braids whose closures are unlinks. We describe canonical forms of these braids and of their conjugacy classes.
Band surgery is an operation relating pairs of knots or links in the three-sphere. We prove that if two quasi-alternating knots K and K′ of the same square-free determinant are related by a band surgery, then the absolute value of the difference in their signatures is either 0 or 8. This obstruction follows from a …
Turning the skein relation for HOMFLY into a Fibonacci recurrence, we prove that there are only three rational specializations of HOMFLY polynomial: Alexander-Conway, Jones, and a new one. Using the recurrence relation, we find general and relative expansion formulae and rational generating functions for Alexander-Conw…
We give a complete classification of homomorphisms from the braid group on n strands to the braid group on 2n strands when n is at least 5. We also classify endomorphisms of the braid group on 4 strands, as well as homomorphisms from the commutator subgroup of the braid group on n strands to the braid group on …
We study the topology of exact and Stein fillings of the canonical contact structure on the unit cotangent bundle of a closed surface Σg, where g is at least 2. In particular, we prove a uniqueness theorem asserting that any Stein filling must be s-cobordant rel boundary to the disk cotangent bundle of Σg. For …
Given knots K and J, one can ask whether a single smoothing of a crossing in a diagram for K can convert it into a diagram for J. As an interesting example, Zekovic discovered that the torus knot T(2,5) can be converted into T(2,-5) with a single smoothing. On the other hand, Moore and Vasquez have shown that among tor…
In the 1970s, Birman-Craggs-Johnson used Rochlin's invariant for homology 3-spheres to construct a remarkable surjective homomorphism sigma:I_{g,1}->B_3, where I_{g,1} is the Torelli group and B_3 is a certain F_2-vector space of Boolean (square-free) polynomials. By pulling back cohomology classes and evaluating them …
Let Γ<SL2(Z) be a non-elementary finitely generated subgroup and let Γ(q) be its congruence subgroup of level q for each q∈N. We obtain an asymptotic formula for the matrix coefficients of L2(Γ(q)\SL2(R)) with a {\it uniform} exponential error term…
Let H be a hyperexponential function in n variables x=(x1,…,xn) with coefficients in a field K, [K:Q]<∞, and ω a rational differential 1-form. Assume that Hω is closed and H transcendental. We prove using Schanuel conjecture that there exist a univariate function…
Cyclotomic polynomials help classify mapping classes on surfaces.
problem Characterizing mapping classes on surfaces using cyclotomic polynomials.
method Investigating characteristic polynomials of integral symplectic matrices and using cyclotomic polynomials to classify them.
result For n≥3, the polynomial φn(x) is realized by a mapping class of algebraically finite type if and only if n has at most two distinct prime divisors.
We present a new proof of Thurston's theorem that the unit ball of a seminorm on Rd taking integer values on Zd is a polyhedra defined by finitely many inequalities with integer coefficients.
We use Nathanson's g-adic representation of integers to relate metric properties of Cayley graphs of the integers with respect to various infinite generating sets S to problems in additive number theory. If S consists of all powers of a fixed integer g, we find explicit formulas for the smallest positive intege…
The integer hull of a polyhedron is the convex hull of the integer points contained in it. We show that the vertices of the integer hulls of a rational family of polyhedra of size O(n) have quasipolynomial coordinates. As a corollary, we show that the stable commutator length of elements in a surgery family is a ratio …
We propose a simple yet powerful framework for modeling integer-valued data, such as counts, scores, and rounded data. The data-generating process is defined by Simultaneously Transforming and Rounding (STAR) a continuous-valued process, which produces a flexible family of integer-valued distributions capable of modeli…