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Thermofield Dynamics of the Heterotic String - Physical Aspects of the Thermal Duality -
The thermofield dynamics of the D = 10 heterotic thermal string theory is
described in proper reference to the thermal duality symmetry as well as the
thermal stability of modular invariance in association with the global phase
structure of the D = 10 heterotic thermal string ensemble.Comment: 8 pages, LaTeX, Minor correction
Emergent states in dense systems of active rods: from swarming to turbulence
Dense suspensions of self-propelled rod-like particles exhibit a fascinating
variety of non-equilibrium phenomena. By means of computer simulations of a
minimal model for rigid self-propelled colloidal rods with variable shape we
explore the generic diagram of emerging states over a large range of rod
densities and aspect ratios. The dynamics is studied using a simple numerical
scheme for the overdamped noiseless frictional dynamics of a many-body system
in which steric forces are dominant over hydrodynamic ones. The different
emergent states are identified by various characteristic correlation functions
and suitable order parameter fields. At low density and aspect ratio, a
disordered phase with no coherent motion precedes a highly-cooperative swarming
state at large aspect ratio. Conversely, at high densities weakly anisometric
particles show a distinct jamming transition whereas slender particles form
dynamic laning patterns. In between there is a large window corresponding to
strongly vortical, turbulent flow. The different dynamical states should be
verifiable in systems of swimming bacteria and artificial rod-like
micro-swimmers.Comment: 14 pages, 8 figure
Weak Quantum Theory: Complementarity and Entanglement in Physics and Beyond
The concepts of complementarity and entanglement are considered with respect
to their significance in and beyond physics. A formally generalized, weak
version of quantum theory, more general than ordinary quantum theory of
material systems, is outlined and tentatively applied to some examples.Comment: Revised version. Chapter 5.2 (old counting) omitted for separate
publication, chapter 5.2 (new counting) reformulate
Xenon forms stable compound with fluorine
Experiments show that xenon and fluorine combine readily at 400 deg C to form xenon tetrafluoride, which is colorless, crystalline, chemically stable and solid at room temperature. This process can be used for the separation of xenon from mixtures with other noble gases
Relation between mutation yield and cell lethality over a wide range of X-ray and fission neutron doses in maize
Dry maize seeds, of a genetic stock heterozygous for the yellow-green locus (Yg^ Î ^ ) Îč were irradiated
with fission neutron doses up to 2700 rads and with 250 kVp X-rays to 40 000 rads. The frequency of
yellow-green (yg) sectors in seedling leaves 4 and 5 is largely a measure of the frequency of breakage (or
incomplete exchange) and loss of the part of the short arm of chromosome I X carrying Yj>. Plots of dose
versus yj* sector frequency per leaf show a linear increase with neutrons which reaches a maximum
(leaf 4 = S. 5, leaf 5 = 2. 5) followed by a rapid decline; and a curvilinear increase with X-rays reaching
a higher maximum (leaf 4 = 8. 5, leaf 5 = 3.6) followed by a decrease. The observed rise and subsequent
fall of numbers of yg_ mutations can be accounted for by a model in which the decline of the curves is
due to cell killing which may also be due to chromosome breakage and deletion. The interpretation is
based on the principles of the dual action theory, which explains radiobiological action in terms of microdosimetry.
One of the observations accounted for is the higher maximum mutation rate for X-rays as
compared to neutrons
Absolute viscosity measured using instrumented parallel plate system
An automatic system measures the true average shear viscosity of liquids and viscoelastic materials, using the parallel plate method and automatically displays the results on a graphic record. This eliminates apparatus setup and extensive calculations
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