Spin-3/2 Fermions in Twistor Formalism

Consistency conditions for the local existence of massless spin 3/2 fields has been explored that the field equations for massless helicity 3/2 are consistent iff the space-time is Ricci-flat and that in Minkowski space-time the space of conserved charges for the fields is its twistor space itself. After considering the twistorial methods to study such massless helicity 3/2 fields, we derive in flat space-time that the charges of spin-3/2 fields defined topologically by the first Chern number of their spin-lowered self-dual Maxwell fields, are given by their twistor space, and in curved space-time that the (anti-)self-duality of the space-time is the necessary condition. Since in N=1 supergravity torsions are the essential ingredients, we generalize our space-time to that with torsion (Einstein-Cartan theory) and have investigated the consistency of existence of spin 3/2 fields in it. A simple solution is found that the space-time has to be conformally (anti-)self-dual, left-(or right-)torsion-free. The integrability condition on $\alpha$-surface shows that the (anti-)self-dual Weyl spinor can be described only by the covariant derivative of the right-(left-)handed-torsion.Comment: 13 pages, Latex2e. The derivations and the conclusions are improve

Simultaneous Smelling an Incense Outdoor and Putting the Hands Together Activate Specific Brain Areas

Mirror neurons are involved in imitation of habitual behaviors. To increase understanding of the theory of mirror neurons and the default mode network, brain activation was explored in 11 healthy adult volunteers who did or did not have a habit of putting their hands together as if praying. Magnetoencephalography (MEG) data were recorded while the participants simultaneously smelled an odor in two kinds of incenses outdoor and/or while they moved to putting their hands together. A magnetoencephalographic contour map of the recorded findings was drawn and an estimated current dipole (ECD) was set. Regardless of a habit of putting their hands together or not, the inner lobe of the frontal area, anterior area in the temporal lobe, and F5 language area in the left frontal lobe and so on were specifically activated. We used cortisol value as an index of the stress state measured in every state (before and after smelling two different incenses outdoor). These experiments suggest that simultaneous smelling an incense outdoor and the behavior of putting their hands together increased the activity of these specific areas in the human brain due to mutual interactions and enhanced interactions

Supersymmetry Breaking and Gravitino Production after Inflation in Modular Invariant Supergravity

By using a string-inspired modular invariant supergravity, which was proved well to explain WMAP observations appropriately, a mechanism of supersymmetry breaking (SSB) and Gravitino Production just after the end of inflation are investigated. Supersymmetry is broken mainly by F-term of the inflaton superfield and the Goldstino is identified to be inflatino in this model, which fact is shown numerically. By using the canonically normalized and diagonalized scalars, the decay rates of these fields are calculated, for both the $T$ and $Y$ into gravitinos. Non-thermal production of gravitinos is not generated from the inflaton (dilaton), since the inflaton mass is lighter than gravitino, but they are produced by the decay of modular field $T$ and scalar field $Y$. Because the reheating temperature $T_R$ is about order $\sim O(10^{10})$ GeV and the mass of gravitino is $3.16 \times 10^{12}$ GeV, it is not reproduced after the reheating of the universe. The gravitinos are produced almost instantly just after the end of inflation through $Y$ and $T$, not from inflaton. Because the decay time appears very rapid, gravitinos disappear before the BBN stage of the universe. The effects of the lightest supersymmetric particles (LSP) produced by gravitinos may be important to investigate more carefully, if the LSP's are the candidate of dark matter.Comment: 11 pages, 1 figure

Dilatonic Inflation, Gravitino and Reheating in Modified Modular invariant Supergravity

A new modified string-inspired modular invariant supergravity model is proposed and is applied to realize the slow roll inflation in Einstein frame, so that the model explains WMAP observations very well. Gravitino mass and their production rate from scalar fields are estimated at certain values of parameters in the model. Seven cases of parameter choices are discussed here, among which some examples show the possibility of observation of gauginos by LHC experiments, which will give some hints of identity of dark matters. The reheating temperature, which is estimated by the stability condition of Boltzmann equation by using the decay rates of the dilaton $S$ into gauginos, is lower than the mass of gravitino. Therefore no thermal reproduction of gravitinos happens. The ratio between the scalar and tensor power spectrum is predicted to be almost the same for the seven cases under study, and its value $r \sim 6.8 \times 10^{-2}$ seems in the range possibly observed by the Planck satellite soon. The plausible supergravity model of inflation, which will be described here, will open the hope to construct a realistic theory of particles and cosmology in this framework, including yet undetected objects.Comment: 12 pages, 4 figures, 2 table

Dilatonic Inflation and SUSY Breaking in String-inspired Supergravity

The theory of inflation will be investigated as well as supersymmetry breaking in the context of supergravity, incorporating the target-space duality and the nonperturbative gaugino condensation in the hidden sector. We found an inflationary trajectory of a dilaton field and a condensate field which breaks supersymmetry at once. The model satisfies the slow-roll condition which solves the eta-problem. When the particle rolls down along the minimized trajectory of the potential V(S,Y) at a duality invariant point of T=1, we can obtain the e-fold value \sim 57. And then the cosmological parameters obtained from our model well match the recent WMAP data combined with other experiments. This observation suggests one to consider the string-inspired supergravity as a fundamental theory of the evolution of the universe as well as the particle theory.Comment: 10 pages, 4 eps figures. Typos and references corrected. Final version to appear in Mod. Phys. Lett.

Low-Frequency Vibrational Spectra of Chlorophylls a and b in Solution: Effects ofAxial Coordination

The far-infrared spectra (500--100 cm-I) of chlorophyll a were observed in three solvent systems (benzene-pyridine, benzene-tetrahydrofuran, and benzene-acetone). The observed spectra could be classified into three types corresponding to the aggregate state, the five-coordinate monomeric state, and the six-coordinate state. The far-infrared spectra of I5N_and 26lV[g-substitutedspecies and the polarized resonance Raman spectra of chlorophyll a and pheophytin a in the region of 500~100 cm-I were studied. These experimental results indicate that bands characteristic of the three states are due to modes to which deformations of the macrocycle make major contributions and vibrations around the Mg atom make some contributions, and that no band observed in the far- -infrared and Raman spectra is attributable to a vibrational mode associated predominantly with the Mg atom and the coordinating atoms. The spectral behavior of chlorophyll b in the benzene-pyridine system was similar to that of chlorophyll a

日中の眠気に及ぼすウルトラディアン・リズムの影響に関する研究

広島大学(Hiroshima University)博士(学術)Sciencedoctora