Imide and isatin derivatives as β-lactam mimics of β-lactam antibiotics

Activated γ-lactams, which are derivatives of succinimide, phthalimide and isatin with suitable elements of molecular recognition, have been synthesised as mimics of the ß-lactam antibiotics and their chemical and biological reactivity determined

Complete Integrability of Geodesic Motion in General Kerr-NUT-AdS Spacetimes

We explicitly exhibit n-1 constants of motion for geodesics in the general D-dimensional Kerr-NUT-AdS rotating black hole spacetime, arising from contractions of even powers of the 2-form obtained by contracting the geodesic velocity with the dual of the contraction of the velocity with the (D-2)-dimensional Killing-Yano tensor. These constants of motion are functionally independent of each other and of the D-n+1 constants of motion that arise from the metric and the D-n = [(D+1)/2] Killing vectors, making a total of D independent constants of motion in all dimensions D. The Poisson brackets of all pairs of these D constants are zero, so geodesic motion in these spacetimes is completely integrable.Comment: 4 pages. We have now found that the geodesic motion is not just integrable, but completely integrabl

Mesoscopic phase statistics of diffuse ultrasound in dynamic matter

Temporal fluctuations in the phase of waves transmitted through a dynamic, strongly scattering, mesoscopic sample are investigated using ultrasonic waves, and compared with theoretical predictions based on circular Gaussian statistics. The fundamental role of phase in Diffusing Acoustic Wave Spectroscopy is revealed, and phase statistics are also shown to provide a sensitive and accurate way to probe scatterer motions at both short and long time scales.Comment: 4 pages, 4 figures, submitted to Physical Review Letter

Proof of the Generalized Second Law for Quasistationary Semiclassical Black Holes

A simple direct explicit proof of the generalized second law of black hole thermodynamics is given for a quasistationary semiclassical black hole.Comment: 12 pages, LaTeX, report Alberta-Thy-10-93 (revision of paper in response to Phys. Rev. Lett. referees' comments, which suffered a series of long delays

Radiation of Charged Particles by Charged Black Hole

The probability of a charged particle production by the electric field of a charged black hole depends essentially on the particle energy. This probability is found in the nonrelativistic and ultrarelativistic limits. The range of values for the mass and charge of a black hole is indicated where the discussed mechanism of radiation is dominating over the Hawking one.Comment: 10 pages, latex, 4 ps-figure

Nonthermal radiation of rotating black holes

Nonthermal radiation of a Kerr black hole is considered as tunneling of created particles through an effective Dirac gap. In the leading semiclassical approximation this approach is applicable to bosons as well. Our semiclassical results for photons and gravitons do not contradict those obtained previously. For neutrinos the result of our accurate quantum mechanical calculation is about two times larger than the previous one.Comment: 10 pages, 2 figures; 2 references added, few typos correcte

Constants of Geodesic Motion in Higher-Dimensional Black-Hole Spacetimes

In [arXiv:hep-th/0611083] we announced the complete integrability of geodesic motion in the general higher-dimensional rotating black-hole spacetimes. In the present paper we prove all the necessary steps leading to this conclusion. In particular, we demonstrate the independence of the constants of motion and the fact that they Poisson commute. The relation to a different set of constants of motion constructed in [arXiv:hep-th/0612029] is also briefly discussed.Comment: 8 pages, no figure

Improved Approximations for Fermion Pair Production in Inhomogeneous Electric Fields

Reformulating the instantons in a complex plane for tunneling or transmitting states, we calculate the pair-production rate of charged fermions in a spatially localized electric field, illustrated by the Sauter electric field E_0 sech^2 (z/L), and in a temporally localized electric field such as E_0 sech^2 (t/T). The integration of the quadratic part of WKB instanton actions over the frequency and transverse momentum leads to the pair-production rate obtained by the worldline instanton method, including the prefactor, of Phys. Rev. D72, 105004 (2005) and D73, 065028 (2006). It is further shown that the WKB instanton action plus the next-to-leading order contribution in spinor QED equals the WKB instanton action in scalar QED, thus justifying why the WKB instanton in scalar QED can work for the pair production of fermions. Finally we obtain the pair-production rate in a spatially localized electric field together with a constant magnetic field in the same direction.Comment: RevTex, 12 pages, two figures; replaced by the version accepted in Phys. Rev.

Solving the degeneracy of the lepton-flavor mixing angle theta_atm by the T2KK two detector neutrino oscillation experiment

If the atmospheric neutrino oscillation amplitude, sin^2 2theta_atm is not maximal, there is a two fold ambiguity in the neutrino parameter space: sin^2 theta_atm>0.5 or sin^2 theta_atm<0.5. In this article, we study the impact of this degeneracy, the so-called octant degeneracy, on the T2KK experiment, which is a proposed extension of the T2K (Tokai-to-Kaimoka) neutrino oscillation experiment with an additional water cherenkov detector placed in Korea. We find that the degeneracy between sin^2 theta_atm= 0.40 and 0.60 can be resolved at the 3sigma level for sin^2 2theta_rct>0.12 (0.08) for the optimal combination of a 3.0^circ off-axis beam (OAB) at SK (L=295km) and a 0.5^circ OAB at L=1000km with a far detector of 100kton volume, after 5 years of exposure with 1.0(5.0) time 10^21 POT/year, if the hierarchy is normal. We also study the influence of the octant degeneracy on the capability of T2KK experiment to determine the mass hierarchy and the leptonic CP phase. The capability of rejecting the wrong mass hierarchy grows with increasing sin^2 theta_atm when the hierarchy is normal, whereas it is rather insensitive to sin^2 theta_atm for the inverted hierarchy. We also find that the 1sigma allowed region of the CP phase is not affected significantly even when the octant degeneracy is not resolved. All our results are obtained for the 22.5 kton Super-Kamiokande as a near detector and without an anti-neutrino beam.Comment: 23 pages, 9 figure

Complex Instantons and Charged Rotating Black Hole Pair Creation

We consider the general process of pair-creation of charged rotating black holes. We find that instantons which describe this process are necessarily complex due to regularity requirements. However their associated probabilities are real, and fully consistent with the interpretation that the entropy of a charged rotating black hole is the logarithm of the number of its quantum states.Comment: 11 pages, 1 figure, Latex, text shortened with only minor changes in content, accepted for Phys Rev Letter