Entangled Light in Moving Frames

We calculate the entanglement between a pair of polarization-entangled photon beams as a function of the reference frame, in a fully relativistic framework. We find the transformation law for helicity basis states and show that, while it is frequency independent, a Lorentz transformation on a momentum-helicity eigenstate produces a momentum-dependent phase. This phase leads to changes in the reduced polarization density matrix, such that entanglement is either decreased or increased, depending on the boost direction, the rapidity, and the spread of the beam.Comment: 4 pages and 3 figures. Minor corrections, footnote on optimal basis state

T violation and the unidirectionality of time

An increasing number of experiments at the Belle, BNL, CERN, DA{\Phi}NE and SLAC accelerators are confirming the violation of time reversal invariance (T). The violation signifies a fundamental asymmetry between the past and future and calls for a major shift in the way we think about time. Here we show that processes which violate T symmetry induce destructive interference between different paths that the universe can take through time. The interference eliminates all paths except for two that represent continuously forwards and continuously backwards time evolution. Evidence from the accelerator experiments indicates which path the universe is effectively following. This work may provide fresh insight into the long-standing problem of modeling the dynamics of T violation processes. It suggests that T violation has previously unknown, large-scale physical effects and that these effects underlie the origin of the unidirectionality of time. It may have implications for the Wheeler-DeWitt equation of canonical quantum gravity. Finally it provides a view of the quantum nature of time itself.Comment: 24 pages, 5 figures. Final version accepted for publishing in Foundations of Physics. The final publication is available at http://www.springerlink.com/content/y3h4174jw2w78322

Local Hidden Variables Underpinning of Entanglement and Teleportation

Entangled states whose Wigner functions are non-negative may be viewed as being accounted for by local hidden variables (LHV). Recently, there were studies of Bell's inequality violation (BIQV) for such states in conjunction with the well known theorem of Bell that precludes BIQV for theories that have LHV underpinning. We extend these studies to teleportation which is also based on entanglement. We investigate if, to what extent, and under what conditions may teleportation be accounted for via LHV theory. Our study allows us to expose the role of various quantum requirements. These are, e.g., the uncertainty relation among non-commuting operators, and the no-cloning theorem which forces the complete elimination of the teleported state at its initial port.Comment: 24 pages, 1 figure, accepted Found. Phy

Vacuum Fluctuations, Geometric Modular Action and Relativistic Quantum Information Theory

A summary of some lines of ideas leading to model-independent frameworks of relativistic quantum field theory is given. It is followed by a discussion of the Reeh-Schlieder theorem and geometric modular action of Tomita-Takesaki modular objects associated with the quantum field vacuum state and certain algebras of observables. The distillability concept, which is significant in specifying useful entanglement in quantum information theory, is discussed within the setting of general relativistic quantum field theory.Comment: 26 pages. Contribution for the Proceedings of a Conference on Special Relativity held at Potsdam, 200

Study of the Process e+e−→KL0KS0e^+e^- \to K^0_L K^0_S in the C.M.Energy Range 1.05-1.38 GeV with CMD-2

The process $e^+e^- \to K^0_L K^0_S$ has been studied with the CMD-2 detector using about 950 events detected in the center-of-mass energy range from 1.05 to 1.38 GeV. The cross section exceeds the expectation based on the contributions of the rho(770), omega(782) and phi(1020) mesons only.Comment: 12 pages, 3 figures, uses elsart.cls, submitted to Physics Letters

High-statistics measurement of the pion form factor in the rho-meson energy range with the CMD-2 detector

We present a measurement of the pion form factor based on e+e- annihilation data from the CMD-2 detector in the energy range 0.6<sqrt(s)<1.0 GeV with a systematic uncertainty of 0.8%. A data sample is five times larger than that used in our previous measurement.Comment: 18 pages, 10 figures. Added comparison with KLOE measurement, minor updates. Accepted by PL

The methylation inhibitor 3DZNep promotes HDR pathway choice during CRISPR-Cas9 genome editing

Alteration of specific epigenetic marks might promote homology directed repair (HDR) during CRISPR-Cas9 genome editing. Testing several epigenetic inhibitors in a traffic light reporter assay, the histone methylation inhibitor 3DZNep showed a significant HDR promoting effect, while non-homologous end joining mediated repair was not significantly changed. This HDR promoting effect was largely independent of the target gene and its expression levels but showed a limited cell type specificity. HDR promotion was independent of the best described target of 3DZNep, the H3K27 methyltransferase EZH2, and of altered gene expression, but correlated partially with increased frequency of S/G2 cell cycle stage

Quantum optics in the phase space - A tutorial on Gaussian states

In this tutorial, we introduce the basic concepts and mathematical tools needed for phase-space description of a very common class of states, whose phase properties are described by Gaussian Wigner functions: the Gaussian states. In particular, we address their manipulation, evolution and characterization in view of their application to quantum information.Comment: Tutorial. 23 pages, 1 figure. Updated version accepted for publication in EPJ - ST devoted to the memory of Federico Casagrand

Entanglement, Bell Inequalities and Decoherence in Particle Physics

We demonstrate the relevance of entanglement, Bell inequalities and decoherence in particle physics. In particular, we study in detail the features of the ``strange'' $K^0 \bar K^0$ system as an example of entangled meson--antimeson systems. The analogies and differences to entangled spin--1/2 or photon systems are worked, the effects of a unitary time evolution of the meson system is demonstrated explicitly. After an introduction we present several types of Bell inequalities and show a remarkable connection to CP violation. We investigate the stability of entangled quantum systems pursuing the question how possible decoherence might arise due to the interaction of the system with its ``environment''. The decoherence is strikingly connected to the entanglement loss of common entanglement measures. Finally, some outlook of the field is presented.Comment: Lectures given at Quantum Coherence in Matter: from Quarks to Solids, 42. Internationale Universit\"atswochen f\"ur Theoretische Physik, Schladming, Austria, Feb. 28 -- March 6, 2004, submitted to Lecture Notes in Physics, Springer Verlag, 45 page