Law Behind Second Law of Thermodynamics --Unification with Cosmology--

In an abstract setting of a general classical mechanical system as a model for the universe we set up a general formalism for a law behind the second law of thermodynamics, i.e. really for "initial conditions". We propose a unification with the other laws by requiring similar symmetry and locality properties.Comment: 17 page

Structure of the neutron-rich N=7 isotones 10Li and 9He

The near threshold structure of the unbound N=7 isotones 10Li and 9He has been investigated using proton removal and breakup from intermediate energy (35 MeV/nucleon) secondary beams of 11Be and 14,15B. The coincident detection of the beam velocity 9Li and 8He fragments and neutrons permitted the relative energy of the in-flight decay of 10Li and 9He to be reconstructed. Both systems were found to exhibited virtual s-wave strength near threshold together with a higher-lying resonance.Comment: 4 pages, 2 figures, Contribution to INPC2010 - "International Nuclear Physics Conference", Vancouver, Canada, 4-9 July 2010, Proceedings to be published in Journal of Physics: Conference Serie

Geons of Galileons

We suggest that galileon theories should have an additional self-coupling of the fields to the trace of their own energy-momentum tensor. We explore the classical features of one such model, in flat 4D spacetime, with emphasis on solutions that are scalar analogues of gravitational geons. We discuss the stability of these scalar geons, and some of their possible signatures, including shock fronts.Comment: References added in v

Effects of R-parity violating supersymmetry in top pair production at linear colliders with polarized beams

In the minimal supersymmetric standard model with R-parity violation, the lepton number violating top quark interactions can contribute to the top pair production at a linear collider via tree-level u-channel squark exchange diagrams. We calculate such contributions and find that in the allowed range of these R-violating couplings, the top pair production rate as well as the top quark polarization and the forward-backward asymmetry can be significantly altered. By comparing the unpolarized beams with the polarized beams, we find that the polarized beams are more powerful in probing such new physics.Comment: 10 pages, 6 fig

T-odd Correlations in the Decay of Scalar Fermions

We define a CP sensitive asymmetry in the sfermion decays \ti f \to f \ti\chi^0_j \ell \bar \ell, f \ti\chi^0_j q \bar q, based on triple product correlations between the momenta of the outgoing fermions. We study this asymmetry in the MSSM with complex parameters. We show that the asymmetry is sensitive to the phases of the parameters $\mu$ and $M_1$. The leading contribution stems from the decay chain \ti f\to f \ti\chi^0_j\to f \ti\chi^0_1 Z\to f \ti\chi^0_1 \ell \bar \ell (f \ti\chi^0_1 q \bar q), for which we obtain analytic formulae for the amplitude squared. The asymmetry can go up to 3% for \ti f\to f \ti\chi^0_1 \ell \bar \ell, and up to 20% for \ti f\to f \ti\chi^0_1 q \bar q. We also estimate the rates necessary to measure the asymmetry.Comment: 18 pages, 5 figures, 2 tables; comments and references added; two tables added; version to appear in Eur. Phys.

Magnetic reordering in the vicinity of a ferromagnetic/antiferromagnetic interface

The magnetic arrangement in the vicinity of the interface between a ferromagnet and an antiferromagnet is investigated, in particular its dependence on the exchange couplings and the temperature. Applying a Heisenberg model, both sc(001) and fcc(001) lattices are considered and solved by a mean field approximation. Depending on the parameter values a variety of different magnetic configurations emerge. Usually the subsystem with the larger ordering temperature induces a magnetic order into the other one (magnetic proximity effect). With increasing temperature a reorientation of the magnetic sublattices is obtained. For coupled sc(001) systems both FM and AFM films are disturbed from their collinear magnetic order, hence exhibit a similar behavior. This symmetry is absent for fcc(001) films which, under certain circumstances, may exhibit two different critical temperatures. Analytical results are derived for simple bilayer systems.Comment: accepted for publication in Eur. Phys. J.

Kink Confinement and Supersymmetry

We analyze non-integrable deformations of two-dimensional N=1 supersymmetric quantum field theories with kink excitations. As example, we consider the multi-frequency Super Sine Gordon model. At weak coupling, this model is robust with respect to kink confinement phenomena, in contrast to the purely bosonic case. If we vary the coupling, the model presents a sequence of phase transitions, where pairs of kinks disappear from the spectrum. The phase transitions fall into two classes: the first presents the critical behaviors of the Tricritical Ising model, the second instead those of the gaussian model. In the first case, close to the critical point, the model has metastable vacua, with a spontaneously supersymmetry breaking. When the life-time of the metastable vacua is sufficiently long, the role of goldstino is given by the massless Majorana fermion of the Ising model. On the contrary, supersymmetry remains exact in the phase transition of the second type.Comment: 29 pages, 12 figure

How fast is the wave function collapse?

Using complex quantum Hamilton-Jacobi formulation, a new kind of non-linear equations is proposed that have almost classical structure and extend the Schroedinger equation to describe the collapse of the wave function as a finite-time process. Experimental bounds on the collapse time are reported (of order 0.1 ms to 0.1 ps) and its convenient dimensionless measure is introduced. This parameter helps to identify the areas where sensitive probes of the possible collapse dynamics can be done. Examples are experiments with Bose-Einstein condensates, ultracold neutrons or ultrafast optics.Comment: 9 pages; v2: a shorter version to suit the 4 page limit of Proceedings of International Conference on Mathematical Modelling in Physical Sciences, 3-7 September 2012, Budapest, Hungary (IC-MSQUARE 2012

Quantum error correction of coherent errors by randomization

A general error correction method is presented which is capable of correcting coherent errors originating from static residual inter-qubit couplings in a quantum computer. It is based on a randomization of static imperfections in a many-qubit system by the repeated application of Pauli operators which change the computational basis. This Pauli-Random-Error-Correction (PAREC)-method eliminates coherent errors produced by static imperfections and increases significantly the maximum time over which realistic quantum computations can be performed reliably. Furthermore, it does not require redundancy so that all physical qubits involved can be used for logical purposes.Comment: revtex 4 pages, 3 fig

Signatures of Chiral Dynamics in Low Energy Compton Scattering off the Nucleon

We present a projector formalism which allows to define dynamical polarizabilities of the nucleon from a multipole expansion of the nucleon Compton amplitudes. We give predictions for the energy dependence of these dynamical polarizabilities both from dispersion theory and from leading-one-loop chiral effective field theory. Based on the good agreement between the two theoretical frameworks, we conclude that the energy dependence of the dynamical polarizabilities is dominated by chiral dynamics, except in those multipole channels where the first nucleon resonance Delta(1232) can be excited. Both the dispersion theory framework and a chiral effective field theory with explicit Delta(1232) degrees of freedom lead to a very good description of the available low energy proton Compton data. We discuss the sensitivity of the proton Compton cross section to dynamical polarizabilities of different multipole content and present a fit of the static electric and magnetic dipole polarizabilities from low-energy Compton data up to omega=170 MeV, finding alpha_E=(11.04+-1.36)*10^(-4) fm^3, beta_M =(2.76-+1.36)*10^(-4) fm^3.Comment: 43 pages, 13 figure