Free Fermion Cyclic/Symmetric Orbifold CFTs and Entanglement Entropy

In this paper we study the properties of two-dimensional CFTs defined by cyclic and symmetric orbifolds of free Dirac fermions, especially by focusing on the partition function and entanglement entropy. Via the bosonization, we construct the twist operators which glue two complex planes to calculate the partition function of Z_2 orbifold CFT on a torus. We also find an expression of Z_N cyclic orbifold in terms of Hecke operators, which provides an explicit relation between the partition functions of cyclic orbifolds and those of symmetric ones. We compute the entanglement entropy and Renyi entropy in cyclic orbifolds on a circle both for finite temperature states and for time-dependent states under quantum quenches. We find that the replica method calculation is highly non-trivial and new because of the contributions from replicas with different boundary conditions. We find the full expression for the Z_2 orbifold and show that the periodicity gets doubled. Finally, we discuss extensions of our results on entanglement entropy to symmetric orbifold CFTs and make a heuristic argument towards holographic CFTs.Comment: 54 pages, 8 figure

Ionic Liquid Fluorohydrogenates and Their Applications

The recent results are described on the developments of ionic liquid (IL) fluorohydrogenates with high ionic conductivities and wide electrochemical windows. Several cyclic ammonium cations have been found to be combined with fluorohydrogenate anions giving a vacuum stable ionic liquid fluorohydrogenates, Cat+[(FH)2.3F]−. N-ethyl-N-methylpyrrolidinium fluorohydrogenate, EMPyrro(FH)2.3F, and N-allylpyrridinium fluorohydrogenate, APyrrid(FH)2.3F, exhibit wide electrochemical windows of around 5 V. A fluorohydrogenate fuel cell (FHFC) using HF-deficient IL, 1-ethyl-3-methyl- imidazolium fluorohydrogenate, EMIm(FH)1.3F, as the electrolyte operates at 120{degree sign}C without humidification. The maximum output power so far obtained in the preliminary cell test is 41 mWcm-2 (0.41 V and 100 mA cm-2) at 40{degree sign}C without humidification

Machine learning reveals orbital interaction in crystalline materials

We propose a novel representation of crystalline materials named orbital-field matrix (OFM) based on the distribution of valence shell electrons. We demonstrate that this new representation can be highly useful in mining material data. Our experiment shows that the formation energies of crystalline materials, the atomization energies of molecular materials, and the local magnetic moments of the constituent atoms in transition metal--rare-earth metal bimetal alloys can be predicted with high accuracy using the OFM. Knowledge regarding the role of coordination numbers of transition-metal and rare-earth metal elements in determining the local magnetic moment of transition metal sites can be acquired directly from decision tree regression analyses using the OFM.Comment: 10 page

Wedge holography in flat space and celestial holography

In this paper, we study codimension two holography in flat spacetimes, based on the idea of the wedge holography. We propose that a region in a d+1 dimensional flat spacetime surrounded by two end of the world branes, which are given by d dimensional hyperbolic spaces, is dual to a conformal field theory (CFT) on a d-1 dimensional sphere. Similarly, we also propose that a d+1 dimensional region in the flat spacetime bounded by two d dimensional de Sitter spaces is holographically dual to a CFT on a d-1 dimensional sphere. Our calculations of the partition function, holographic entanglement entropy and two point functions, support these duality relations and imply that such CFTs are nonunitary. Finally, we glue these two dualities along null surfaces to realize a codimension two holography for a full Minkowski spacetime and discuss a possible connection to the celestial holography

Celestial CFT from H⁺₃-WZW Model

Recently, there has been a growing interest in celestial holography, which is holography in asymptotically flat spacetimes. This holographic duality exhibits numerous mysterious and fruitful features, particularly on the dual CFT side. In this paper, we present the candidate of dual CFT for Minkowski spacetime extracted from SL(2, ℂ)／SU(2)≅H⁺₃ Wess-Zumino-Witten (WZW) model, the simplest non-compact CFT. We demonstrate that it reproduces the well-known principal series and correlation functions dual to the bulk scattering amplitudes

An Efficient Prediction Model for OTC Medicine Effect with the Package Inserts Information

AbstractIn Japan, general public those who are not medical experts usually buy OTC medicine at a pharmacy, depending on their illness condition. In this case, it is difficult for them to consider how much the OTC medicine is effective for their symptom. The components of OTC medicine have been used as ethical medicines for a long period of time.This is because the efficacy and safety of ethical medicine have been confirmed before being employed as OTC medicine. The information of those confirmed medicines is described in package inserts, which is aimed for medical professionals. Therefore, it is difficult for general public to understand what the package insert describes in terms of medical effects.In this study, from the information which appears in the package inserts of prescription medicines, a method for estimating the effect of OTC medicine is investigated. Also, a method of estimating the effects of medicines without directly compared data is proposed, only by using the information of package inserts of ethical medicines

Solvent-Dependent Conformation of Amylose Tris(Phenylcarbamate) as Deduced from Scattering and Viscosity Data

The z-average mean-square radius of gyration 〈S^2〉_z, the particle scattering function P(k), the second virial coefficient, and the intrinsic viscosity [η] have been determined for amylose tris(phenylcarbamate) (ATPC) in methyl acetate (MEA) at 25°C, in ethyl acetate (EA) at 33°C, and in 4-methyl-2-pentanone (MIBK) at 25°C by light and small-angle X-ray scattering and viscometry as functions of the weight-average molecular weight in a range from 2 × 10^4 to 3 × 10^6. The first two solvents attain the theta state, whereas the last one is a good solvent for the amylose derivative. Analysis of the 〈S^2〉_z, P(k), and [η] data based on the wormlike chain yields h (the contour length or helix pitch per repeating unit) = 0.37 ± 0.02 and λ^ (the Kuhn segment length) = 15 ± 2 nm in MEA, h = 0.39 ± 0.02 and λ^ = 17 ± 2 nm in EA, and h = 0.42 ± 0.02 nm and λ^ = 24 ± 2 nm in MIBK. These h values, comparable with the helix pitches (0.37–0.40 nm) per residue of amylose triesters in the crystalline state, are somewhat larger than the previously determined h of 0.33 ± 0.02 nm for ATPC in 1,4-dioxane and 2-ethoxyethanol, in which intramolecular hydrogen bonds are formed between the C[DOUBLE BOND]O and NH groups of the neighbor repeating units. The slightly extended helices of ATPC in the ketone and ester solvents are most likely due to the replacement of those hydrogen bonds by intermolecular hydrogen bonds between the NH groups of the polymer and the carbonyl groups of the solvent.This is the peer reviewed version of the following article: Taichi Fujii1, Ken Terao, Maiko Tsuda, Shinichi Kitamura, Takashi Norisuye, “Solvent-dependent conformation of amylose tris(phenylcarbamate) as deduced from scattering and viscosity data”, Biopolymers, Volume 91, Issue 9, pages 729–736, September 2009, which has been published in final form at DOI: 10.1002/bip.21219. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving