On the Ground State Wave Function of Matrix Theory

We propose an explicit construction of the leading terms in the asymptotic expansion of the ground state wave function of BFSS SU(N) matrix quantum mechanics. Our proposal is consistent with the expected factorization property in various limits of the Coulomb branch, and involves a different scaling behavior from previous suggestions. We comment on some possible physical implications.Comment: 21 page

Convexity of ruin probability and optimal dividend strategies for a general Levy process

In this paper, we consider the optimal dividends problem for a company whose cash reserves follow a general Levy process with certain positive jumps and arbitrary negative jumps. The objective is to find a policy which maximizes the expected discounted dividends until the time of ruin. Under appropriate conditions, we appeal to very recent results in the theory of potential analysis of subordinators to obtain the convexity properties of probability of ruin. We present conditions under which the optimal dividend strategy, among all admissible ones, takes the form of a barrier strategy.Comment: 19 pages, corrected some typo

Dual-topology insertion of a dual-topology membrane protein.

Some membrane transporters are dual-topology dimers in which the subunits have inverted transmembrane topology. How a cell manages to generate equal populations of two opposite topologies from the same polypeptide chain remains unclear. For the dual-topology transporter EmrE, the evidence to date remains consistent with two extreme models. A post-translational model posits that topology remains malleable after synthesis and becomes fixed once the dimer forms. A second, co-translational model, posits that the protein inserts in both topologies in equal proportions. Here we show that while there is at least some limited topological malleability, the co-translational model likely dominates under normal circumstances

Deterministic modelling of energy supply and demand for foaling mares managed at pasture on commercial thoroughbred stud farms : a thesis presented in fulfilment of requirement for the degree, Master of Science (Animal Science), Massey University, Palmerston North, New Zealand

There is an economic incentive to breed and foal mares early in the season within the New Zealand commercial Thoroughbred production industry. This has caused disparity between the natural and commercially imposed breeding season, and possibly, the period of peak pasture energy availability and the mare energy requirements. A deterministic model was developed to model the energy balance, energy intake and energy requirement of Thoroughbred mares managed at pasture under commercial conditions to assess their energy status. The response of energy intake and energy balance to changes in five variables were tested. The variables tested were dry matter intake, bodyweight, foaling date, pasture metabolisable energy, and energy requirement. For all foaling dates modelled, the mare was in energy surplus during pregnancy. Onset of lactation created a rapid and significant decrease in mare energy balance. Delay in foaling increased the magnitude of the post-partum energy deficit, and later foaling mares experienced a prolonged decrease in post-partum energy balance. The size of the deficit would, theoretically, decrease 1 body condition score, decrease circulating leptin concentration and initiate lean body mass mobilization which was previously found to negatively impact reproductive performance in the mares. The duration and size of the post-partum energy deficit could be reduced by shifting foaling date closer to the beginning of breeding season (1st September), thus synchronizing period of peak pasture energy with the mare’s theoretical requirements. Energy balance and energy intake were more sensitive to pasture energy, dry matter intake and energy requirement changes with less influence from bodyweight to energy balance, suggesting pasture quality and quantity is an important influencer on nutritional status of the mare kept on pasture. Initiatives should be taken to monitor pasture quality and growth pattern, and optimize energy and dry matter intake in mares at pasture. These efforts could assist in maximizing pasture utilization, minimize energy deficit and achieve cost effective pastoral and nutritional management. When more pasture quality and growth data becomes available for equine stud farms, the model has the potential to achieve farm specific application on a wide range of equine body weights

(2,2) Superconformal Bootstrap in Two Dimensions

We find a simple relation between two-dimensional BPS N=2 superconformal blocks and bosonic Virasoro conformal blocks, which allows us to analyze the crossing equations for BPS 4-point functions in unitary (2,2) superconformal theories numerically with semidefinite programming. We constrain gaps in the non-BPS spectrum through the operator product expansion of BPS operators, in ways that depend on the moduli of exactly marginal deformations through chiral ring coefficients. In some cases, our bounds on the spectral gaps are observed to be saturated by free theories, by N=2 Liouville theory, and by certain Landau-Ginzburg models.Comment: 56 pages, 14 figure

Supersymmetry Constraints and String Theory on K3

We study supervertices in six dimensional (2,0) supergravity theories, and derive supersymmetry non-renormalization conditions on the 4- and 6-derivative four-point couplings of tensor multiplets. As an application, we obtain exact non-perturbative results of such effective couplings in type IIB string theory compactified on K3 surface, extending previous work on type II/heterotic duality. The weak coupling limit thereof, in particular, gives certain integrated four-point functions of half-BPS operators in the nonlinear sigma model on K3 surface, that depend nontrivially on the moduli, and capture worldsheet instanton contributions.Comment: 47 pages, 4 figure