The twisted fourth moment of the Riemann zeta function

We compute the asymptotics of the fourth moment of the Riemann zeta function times an arbitrary Dirichlet polynomial of length $T^{{1/11} - \epsilon}$Comment: 28 pages. v2: added reference

MACHO Mass Determination Based on Space Telescope Observation

We investigate the possibility of lens mass determination for a caustic crossing microlensing event based on a space telescope observation. We demonstrate that the parallax due to the orbital motion of a space telescope causes a periodic fluctuation of the light curve, from which the lens distance can be derived. Since the proper motion of the lens relative to the source is also measurable for a caustic crossing event, one can find a full solution for microlensing properties of the event, including the lens mass. To determine the lens mass with sufficient accuracy, the light curve near the caustic crossing should be observed within uncertainty of $\sim$ 1%. We argue that the Hubble Space Telescope observation of the caustic crossing supplied with ground-based observations of the full light curve will enable us to determine the mass of MACHOs, which is crucial for understanding the nature of MACHOs.Comment: 9 pages + 3 figures, accepted for publication in ApJ Letter

Nonlocal Effects of Partial Measurements and Quantum Erasure

Partial measurement turns the initial superposition not into a definite outcome but into a greater probability for it. The probability can approach 100%, yet the measurement can undergo complete quantum erasure. In the EPR setting, we prove that i) every partial measurement nonlocally creates the same partial change in the distant particle; and ii) every erasure inflicts the same erasure on the distant particle's state. This enables an EPR experiment where the nonlocal effect does not vanish after a single measurement but keeps "traveling" back and forth between particles. We study an experiment in which two distant particles are subjected to interferometry with a partial "which path" measurement. Such a measurement causes a variable amount of correlation between the particles. A new inequality is formulated for same-angle polarizations, extending Bell's inequality for different angles. The resulting nonlocality proof is highly visualizable, as it rests entirely on the interference effect. Partial measurement also gives rise to a new form of entanglement, where the particles manifest correlations of multiple polarization directions. Another novelty in that the measurement to be erased is fully observable, in contrast to prevailing erasure techniques where it can never be observed. Some profound conceptual implications of our experiment are briefly pointed out.Comment: To be published in Phys. Rev. A 63 (2001). 19 pages, 12 figures, RevTeX 3.

Magnetocaloric effect and improved relative cooling power in (La0.7Sr0.3MnO3/SrRuO3) superlattices

Magnetic properties of a series of (La0.7Sr0.3MnO3/SrRuO3) superlattices, where the SrRuO3 layer thickness is varying, are examined. A room-temperature magnetocaloric effect is obtained owing to the finite size effect which reduces the TC of La0.7Sr0.3MnO3 layers. While the working temperature ranges are enlarged,, -DeltaSmax values remains similar to the values in polycrystalline La0.7Sr0.3MnO3. Consequently, the relative cooling powers are significantly improved, the microscopic mechanism of which is related to the effect of the interfaces at La0.7Sr0.3MnO3/SrRuO3 and higher nanostructural disorder. This study indicates that artificial oxide superlattices/multilayers might provide an alternative pathway in searching for efficient room-temperature magnetic refrigerators for (nano)microscale systems.Comment: 14^pages, 3 figures, Submitted to J. Phys. Cond. Ma

Induction of Immunological Tolerance to Tissue Allografts with Antilymphocyte Serum

Our interest in the problem of tolerance induction is directly concerned with clinical organ transplantation. ALS is highly effective in depressing cellular immunities. Since at least initial allograft rejection is predominantly a cellular phenomenon, one would expect ALS to be highly effective clinically. Our initial observations in this regard support this concept. However, non-specific depression of cellular immunity may also lead to an increased number or viral, fungal, and protozoan infections. Experiments, such as these presented, strongly suggest that a specific state of tolerance to organ grafts in man should be attainable with the aid of ALS followed by introduction of appropriate antigen

Photoinduced Changes of Reflectivity in Single Crystals of YBa2Cu3O6.5 (Ortho II)

We report measurements of the photoinduced change in reflectivity of an untwinned single crystal of YBa2Cu3O6.5 in the ortho II structure. The decay rate of the transient change in reflectivity is found to decrease rapidly with decreasing temperature and, below Tc, with decreasing laser intensity. We interpret the decay as a process of thermalization of antinodal quasiparticles, whose rate is determined by an inelastic scattering rate of quasiparticle pairs.Comment: 4 pages, 4 figure