QCD thermodynamics with dynamical overlap fermions

We study QCD thermodynamics using two flavors of dynamical overlap fermions with quark masses corresponding to a pion mass of 350 MeV. We determine several observables on N_t=6 and 8 lattices. All our runs are performed with fixed global topology. Our results are compared with staggered ones and a nice agreement is found.Comment: 14 pages, 6 figures, 1 tabl

On a two variable class of Bernstein-Szego measures

The one variable Bernstein-Szego theory for orthogonal polynomials on the real line is extended to a class of two variable measures. The polynomials orthonormal in the total degree ordering and the lexicographical ordering are constructed and their recurrence coefficients discussed.Comment: minor change

Unification through extra dimensions at two loops

The presence of an extra dimension of size R\equiv M_c^{-1} introduces corrections of order (\mu/M_c)\alpha to the gauge and Yukawa couplings and accelerates their running at scales \mu larger than M_c. This could result in a grand unification scale M_X\approx 20 M_c. We study the corrections at the two-loop level. We find corrections of order (\mu/M_c)\alpha^2 for the gauge couplings and of order (\mu/M_c)^2\alpha^2 for the Yukawa couplings. Therefore, in the Yukawa sector one and two-loop contributions can be of the same order below M_X. We show that in the usual scenarios the dominant gauge and Yukawa couplings are decreasing functions of the scale, in such a way that (\mu/M_c)\alpha becomes approximately constant and two-loop contributions introduce just a 30% correction which does not increase with the scale.Comment: 14 pages, added references, corrected typo

The Fourth Element: Characteristics, Modelling, and Electromagnetic Theory of the Memristor

In 2008, researchers at HP Labs published a paper in {\it Nature} reporting the realisation of a new basic circuit element that completes the missing link between charge and flux-linkage, which was postulated by Leon Chua in 1971. The HP memristor is based on a nanometer scale TiO$_2$ thin-film, containing a doped region and an undoped region. Further to proposed applications of memristors in artificial biological systems and nonvolatile RAM (NVRAM), they also enable reconfigurable nanoelectronics. Moreover, memristors provide new paradigms in application specific integrated circuits (ASICs) and field programmable gate arrays (FPGAs). A significant reduction in area with an unprecedented memory capacity and device density are the potential advantages of memristors for Integrated Circuits (ICs). This work reviews the memristor and provides mathematical and SPICE models for memristors. Insight into the memristor device is given via recalling the quasi-static expansion of Maxwell's equations. We also review Chua's arguments based on electromagnetic theory.Comment: 28 pages, 14 figures, Accepted as a regular paper - the Proceedings of Royal Society

Molecular crystal approach for pi-conjugated polymers: from PPP Hamiltonian to Holstein model for polaron states

Starting from the $\pi$-electron Pariser-Parr-Pople (PPP) Hamiltonian which includes both strong electron-phonon and electron-electron interactions, we propose some strongly correlated wave functions of increasing quality for the ground state of conjugated polymers. These wavefunctions are built by combining different finite sets of local configurations extended at most over two nearest-neighbour monomers. With this picture, the doped case with one additional particle is expressed in terms of quasi-particle. Thus, the polaron formation problem goes back to the study of a Holstein like model.Comment: 27 pages, 6 eps figs, Revtex; enlarged version. Submitted to Journal of Physics: Condensed Matte

Qudit surface codes and gauge theory with finite cyclic groups

Surface codes describe quantum memory stored as a global property of interacting spins on a surface. The state space is fixed by a complete set of quasi-local stabilizer operators and the code dimension depends on the first homology group of the surface complex. These code states can be actively stabilized by measurements or, alternatively, can be prepared by cooling to the ground subspace of a quasi-local spin Hamiltonian. In the case of spin-1/2 (qubit) lattices, such ground states have been proposed as topologically protected memory for qubits. We extend these constructions to lattices or more generally cell complexes with qudits, either of prime level or of level $d^\ell$ for $d$ prime and $\ell \geq 0$, and therefore under tensor decomposition, to arbitrary finite levels. The Hamiltonian describes an exact $\mathbb{Z}_d\cong\mathbb{Z}/d\mathbb{Z}$ gauge theory whose excitations correspond to abelian anyons. We provide protocols for qudit storage and retrieval and propose an interferometric verification of topological order by measuring quasi-particle statistics.Comment: 26 pages, 5 figure

The effect of mirabegron on patient-related outcomes in patients with overactive bladder: the results of post hoc correlation and responder analyses using pooled data from three randomized Phase III trials

Purpose To understand how improvements in the symptoms of overactive bladder (OAB) seen with the b3-adrenoceptor agonist mirabegron 50 mg, correlate with patient experience as measured by validated and standard patient-reported outcomes (PROs), and to identify whether there is overall directional consistency in the responsiveness of PROs to treatment effect. Methods In a post hoc analysis of pooled data from three randomized, double-blind, placebo-controlled, 12-week Phase III trials of mirabegron 50 mg once daily, responder rates for incontinence frequency (C50 % reduction in incontinence episodes/24 h from baseline to final visit), micturition frequency (B8 micturitions/24 h at final visit), and PROs [minimally important differences in patient perception of bladder condition (PPBC) and subsets of the overactive bladder questionnaire (OAB-q) measuring total health-related quality of life (HRQoL), and symptom bother] were evaluated individually and in combination. Results Mirabegron 50 mg demonstrated greater improvement from baseline to final visit than placebo for each of the responder analyses, whether for individual objective and subjective outcomes or combinations thereof. These improvements versus placebo were statistically significant for all double and triple responder analyses and for all single responder analyses except PPBC. PRO measurements showed directional consistency and significant correlations, and there were also significant correlations between objective and subjective measures of efficacy. Conclusions The improvements in objective measures seen with mirabegron 50 mg translate into a meaningful clinical benefit as evident by the directional consistency seen in HRQoL measures of benefit

Running Coupling with Minimal Length

In models with large additional dimensions, the GUT scale can be lowered to values accessible by future colliders. Due to modification of the loop corrections from particles propagating into the extra dimensions, the logarithmic running of the couplings of the Standard Model is turned into a power law. These loop-correction are divergent and the standard way to achieve finiteness is the introduction of a cut-off. The question remains, whether the results are reliable as they depend on an unphysical parameter. In this paper, we show that this running of the coupling can be calculated within a model including the existence of a minimal length scale. The minimal length acts as a natural regulator and allows us to confirm cut-off computations.Comment: 26 pages, 5 figures, typos corrected, replaced with published versio

Theory of electronic transport through a triple quantum dot in the presence of magnetic field

Theory of electronic transport through a triangular triple quantum dot subject to a perpendicular magnetic field is developed using a tight binding model. We show that magnetic field allows to engineer degeneracies in the triple quantum dot energy spectrum. The degeneracies lead to zero electronic transmission and sharp dips in the current whenever a pair of degenerate states lies between the chemical potential of the two leads. These dips can occur with a periodicity of one flux quantum if only two levels contribute to the current or with half flux quantum if the three levels of the triple dot contribute. The effect of strong bias voltage and different lead-to-dot connections on Aharonov-Bohm oscillations in the conductance is also discussed