23,211 research outputs found
Introduction to Dynamic Unary Encoding
Dynamic unary encoding takes unary encoding to the next level. Every n-bit
binary string is an encoding of dynamic unary and every n-bit binary string is
encodable by dynamic unary. By utilizing both forms of unary code and a single
bit of parity information dynamic unary encoding partitions 2^n non-negative
integers into n sets of disjoint cycles of n-bit elements. These cycles have
been employed as virtual data sets, binary transforms and as a mathematical
object. Characterization of both the cycles and of the cycle spectrum is given.
Examples of encoding and decoding algorithms are given. Examples of other
constructs utilizing the principles of dynamic unary encoding are presented.
The cycle as a mathematical object is demonstrated.Comment: Seven pages of text, two pages of flow charts and two pages of data.
Introduces an encoding scheme and a mathematical objec
(j,0)+(0,j) Covariant spinors and causal propagators based on Weinberg formalism
A pragmatic approach to constructing a covariant phenomenology of the
interactions of composite, high-spin hadrons is proposed. Because there are no
known wave equations without significant problems, we propose to construct the
phenomenology without explicit reference to a wave equation. This is done by
constructing the individual pieces of a perturbation theory and then utilizing
the perturbation theory as the definition of the phenomenology. The covariant
spinors for a particle of spin are constructed directly from Lorentz
invariance and the basic precepts of quantum mechanics following the logic put
forth originally by Wigner and developed by Weinberg. Explicit expressions for
the spinors are derived for j=1, 3/2 and 2. Field operators are constructed
from the spinors and the free-particle propagator is derived from the vacuum
expectation value of the time-order product of the field operators. A few
simple examples of model interactions are given. This provides all the
necessary ingredients to treat at a phenomenological level and in a covariant
manner particles of arbitrary spin.Comment: tex file, 52 page
Charging axisymmetric space-times with cosmological constant
Ernst's solution generating technique for adding electromagnetic charge to
axisymmetric space-times in general relativity is generalised in presence of
the cosmological constant. Ernst equations for complex potentials are found and
they are traced back to an affective dual complex dynamical system, whose
symmetries are studied. In particular this method is able to generate charged,
asymptotically (A)dS black holes from their uncharged version: as an example,
it is shown explicitly how to pass from the Kerr-(A)dS to the Kerr-Newman-(A)dS
metric. A new solution describing a magnetic universe in presence of the
cosmological constant is also generated.Comment: 15 pages, v2: typos correcte
Silver-base ternary alloy proves superior for slip ring lead wires
Slip ring lead wires composed of ternary alloys of silver, have high electrical conductivity, a tensile strength of at least 30,000 psi, high ductility, and are solderable and weldable. An unexpected advantage of these alloys is their resistance to discoloration on heating in air
Thin Ohmic or superconducting strip with an applied ac electric current
The complex impedance, currents, and electric and magnetic fields are
calculated as functions of resistivity and frequency or London depth for a long
thin strip with applied ac current. Both Ohmic and superconducting strips are
considered. While the inductance per unit length of the strip depends on the
strip length logarithmically, the sheet current, magnetic field, resistance,
and magnetic susceptibility are independent of this length. It is found that
the enhancement of resistance by the skin effect in thin Ohmic strips is much
weaker (logarithmic) than in thick wires.Comment: 4 pages, 3 figures, for Phys. Rev.
Microscopic approach to pion-nucleus dynamics
Elastic scattering of pions from finite nuclei is investigated utilizing a
contemporary, momentum--space first--order optical potential combined with
microscopic estimates of second--order corrections. The calculation of the
first--order potential includes:\ \ (1)~full Fermi--averaging integration
including both the delta propagation and the intrinsic nonlocalities in the
- amplitude, (2)~fully covariant kinematics, (3)~use of invariant
amplitudes which do not contain kinematic singularities, and (4)~a
finite--range off--shell pion--nucleon model which contains the nucleon pole
term. The effect of the delta--nucleus interaction is included via the mean
spectral--energy approximation. It is demonstrated that this produces a
convergent perturbation theory in which the Pauli corrections (here treated as
a second--order term) cancel remarkably against the pion true absorption terms.
Parameter--free results, including the delta--nucleus shell--model potential,
Pauli corrections, pion true absorption, and short--range correlations are
presented. (2 figures available from authors)Comment: 13 page
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