136,242 research outputs found
An equation for the description of volume and temperature dependences of the dynamics of supercooled liquids and polymer melts
A recently proposed expression to describe the temperature and volume
dependences of the structural (or alpha) relaxation time is discussed. This
equation satisfies the scaling law for the relaxation times, tau = f(TV^g),
where T is temperature, V the specific volume, and g a material-dependent
constant. The expression for the function f is shown to accurately fit
experimental data for several glass-forming liquids and polymers over an
extended range encompassing the dynamic crossover, providing a description of
the dynamics with a minimal number of parameters. The results herein can be
reconciled with previously found correlations of the isochoric fragility with
both the isobaric fragility at atmospheric pressure and the scaling exponent g.Comment: to be published in the special edition of J. Non-Crystalline Solids
honoring K.L. Nga
Quantum circuit implementation of the Hamiltonian versions of Grover's algorithm
We analyze three different quantum search algorithms, the traditional
Grover's algorithm, its continuous-time analogue by Hamiltonian evolution, and
finally the quantum search by local adiabatic evolution. We show that they are
closely related algorithms in the sense that they all perform a rotation, at a
constant angular velocity, from a uniform superposition of all states to the
solution state. This make it possible to implement the last two algorithms by
Hamiltonian evolution on a conventional quantum circuit, while keeping the
quadratic speedup of Grover's original algorithm.Comment: 5 pages, 3 figure
Time domain calculation of the electromagnetic self-force on eccentric geodesics in Schwarzschild spacetime
I calculate the self-force acting on a particle with electric charge q moving
on a generic geodesic around a Schwarzschild black hole. Using methods similar
to those developed for the scalar field case discussed in a previous paper, I
investigate the relative sizes of the conservative (half-advanced plus
half-retarded) and dissipative (half-advanced minus half-retarded) pieces of
the self-force. I also display the regularization parameters used in the
mode-sum regularization scheme.Comment: 24 pages; 21 figures; revtex
Ray class fields of global function fields with many rational places
A general type of ray class fields of global function fields is investigated.
The systematic computation of their genera leads to new examples of curves over
finite fields with comparatively many rational points.Comment: Latex2e, 27 pages, 20 tables, revised version as submitted to Acta
Arithmetic
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