Quantization of scalar perturbations in brane-world inflation

We consider a quantization of scalar perturbations about a de Sitter brane in a 5-dimensional anti-de Sitter (AdS) bulk spacetime. We first derive the second order action for a master variable $\Omega$ for 5-dimensional gravitational perturbations. For a vacuum brane, there is a continuum of normalizable Kaluza-Klein (KK) modes with $m>3H/2$. There is also a light radion mode with $m=\sqrt{2}H$ which satisfies the junction conditions for two branes, but is non-normalizable for a single brane model. We perform the quantization of these bulk perturbations and calculate the effective energy density of the projected Weyl tensor on the barne. If there is a test scalar field perturbation on the brane, the $m^2 = 2H^2$ mode together with the zero-mode and an infinite ladder of discrete tachyonic modes become normalizable in a single brane model. This infinite ladder of discrete modes as well as the continuum of KK modes with $m>3H/2$ introduce corrections to the scalar field perturbations at first-order in a slow-roll expansion. We derive the second order action for the Mukhanov-Sasaki variable coupled to the bulk perturbations which is needed to perform the quantization and determine the amplitude of scalar perturbations generated during inflation on the brane.Comment: 14 page

Rotationally-Driven Fragmentation for the Formation of the Binary Protostellar System L1551 IRS 5

Either bulk rotation or local turbulence is widely invoked to drive fragmentation in collapsing cores so as to produce multiple star systems. Even when the two mechanisms predict different manners in which the stellar spins and orbits are aligned, subsequent internal or external interactions can drive multiple systems towards or away from alignment thus masking their formation process. Here, we demonstrate that the geometrical and dynamical relationship between the binary system and its surrounding bulk envelope provide the crucial distinction between fragmentation models. We find that the circumstellar disks of the binary protostellar system L1551 IRS 5 are closely parallel not just with each other but also with their surrounding flattened envelope. Measurements of the relative proper motion of the binary components spanning nearly 30 yr indicate an orbital motion in the same sense as the envelope rotation. Eliminating orbital solutions whereby the circumstellar disks would be tidally truncated to sizes smaller than are observed, the remaining solutions favor a circular or low-eccentricity orbit tilted by up to $\sim$25$^\circ$ from the circumstellar disks. Turbulence-driven fragmentation can generate local angular momentum to produce a coplanar binary system, but which bears no particular relationship with its surrounding envelope. Instead, the observed properties conform with predictions for rotationally-driven fragmentation. If the fragments were produced at different heights or on opposite sides of the midplane in the flattened central region of a rotating core, the resulting protostars would then exhibit circumstellar disks parallel with the surrounding envelope but tilted from the orbital plane as is observed.Comment: Accepted for publication in Ap

Development and practical application of unhairing method without using sulfide

Content: Leather manufacturing industry uses a lot of water and chemicals, and it discharges large amounts of wastewater. The processing a large amounts of wastewater requires a huge cost. Therefore, reduction of amount of a pollution load in wastewater is a theme in many countries around the world. During the leather process, a lot of pollutants occur in the unhairing process. Some estimate that the amount of pollution generated in the unhairing process accounts for 70% of the entire leather manufacturing process. In this unhairing process, usually a large amount of sulfide is used. Sulfide is known to generate hydrogen sulfide and cause damage to the drain pipe. In Tokyo, strict criteria are set for draining sulfide to sewers. Therefore, reducing the amount of sulfide used is an important task for tanner. In addition, since sulfide has no degreasing effect, a large amount of surfactant is required in the unhairing process. However, to reduce the cost and the load of the wastewater, it is also required to reduce the amount of the surfactant used. Furthermore, in recent years, the types of usable surfactants have also been limited. Therefore, development of a method of effectively removing hair loss and degreasing without using a sulfide is urgent for the leather manufacturing industry. On the other hand, pelts are widely used as raw materials for foods such as gelatin and collagen casing, cosmetics, and pharmaceuticals. However, sulfides are not originally recognized as food additives. Therefore, some companies are concerned about using pelts as a raw material for food using sulfide in the unhairing process. Also from this point of view, it is necessary to develop an unhairing method without using sulfides. The method using sodium hydroxide has been studied for a long time. However, this method is hard in handling, and is difficult to set conditions such as concentration and temperature. That is, while successful at the experimental level, it has not been put to practical use. Therefore, we studied a method to solve the above problem using sodium hydroxide. The method developed this time can reduce the pollutant in waste water, and the amount of water used in the unhairing process to 1/10 or less of the conventional one. Moreover, since it is not influenced by water temperature, it made it possible to stably remove hair irrespective of the season. The finished leather kept sufficient strength. In addition, sodium hydroxide reacts with fat in the skin and turns it into soap, so it shows the degreasing effect and contributes to reduce the dosage of degreasing agent. Take-Away: development of unhairing method without using sulfide contributes to reduce the dosage of degreasing agent reduce the pollutant in waste wate

A longitudinal investigation of the relationship between motivation and late second language speech learning in classroom settings

The current study set out to examine the role of learner motivation in second language (L2) speech learning in English-as-a-Foreign-Language classrooms. The motivational orientations of 40 first-year university Japanese students were surveyed via a tailored questionnaire and linked to their spontaneous speech development, elicited via a timed picture description task at the onset and end of one academic semester, in terms of perceived comprehensibility (i.e., ease of understanding) and accentedness (i.e., linguistic nativelikeness). Significant improvement in comprehensibility (but not accentedness) was found among certain individuals. These students likely showed a strong motivation to study English for their future career development as a vague and long-term goal, as well as a high degree of concern for improving comprehensibility, grammatical accuracy and complexity

The QCD phase diagram in the space of imaginary chemical potential via 't Hooft anomalies

The QCD phase diagram in the space of temperature and imaginary baryon chemical potential has been an interesting subject in numerical lattice QCD simulations because of the absence of the sign problem and its deep structure related to confinement/deconfinement. We study constraints on the phase diagram by using an 't Hooft anomaly. The relevant anomaly is an anomaly in the space of imaginary chemical potential. We compute it in the UV, and discuss how it is matched by the pion effective field theory at low temperatures. Then we study implications of the anomaly to the phase diagram. There must be a line of phase transition studied in the past by Roberge and Weiss such that the expectation value of the Polyakov loop is not smooth when we cross the line. Moreover, if the greatest common divisor of the color and flavor numbers is greater than one, the phase transition across the Roberge-Weiss line must be either a first order phase transition, or a second order phase transition described by a nontrivial interacting three-dimensional CFT.Comment: 28 pages, 6 figure

Runaway Dynamics and Supersymmetry Breaking

Supersymmetric SU(N_C) gauge theories possess runaway-type superpotentials for N_F < N_C, where N_F is the flavor number of massless quarks. We show that the runaway behavior can be stabilized for N_F nearly equal to N_C by introducing singlets with the aid of perturbative corrections to the Kahler potential, generating (local) minima of supersymmetry breaking.Comment: 6 page

Extraction of an Entanglement by Repetition of the Resonant Transmission of an Ancilla Qubit

A scheme for the extraction of entanglement in two noninteracting qubits (spins) is proposed. The idea is to make use of resonant transmission of ancilla qubit through the two fixed qubits, controlled by the entanglement in the scatterers. Repetition of the resonant transmission extracts the singlet state in the target qubits from their arbitrary given state. Neither the preparation nor the post-selection of the ancilla spin is required, in contrast to the previously proposed schemes.Comment: 14 pages, 7 figure