Lorentz model and time-dependent diffusion.
Time dependent diffusion of light particles of Lorentz fluid approximated by Boltzmann equation leading to microscopic telegrapher equation
Hollinger, H. B.↗
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Quantum-limited detection of an incoherent object with a Lorentz spectrum
Quantum limited detection of incoherent object with Lorentz spectrum
Helstrom, C. W.↗
A test of Lorentz invariance using a torsion pendulum
Lorentz invariance test using bar magnet on torsion fiber, analyzing preferred reference frame in space assuming earth velocity coupled to electron spin through specific term
Phillips, P. R.↗
The Compton-Getting effect for cosmic-ray particles and photons and the Lorentz- invariance of distribution functions
Compton-Getting effect for cosmic ray particles and photons and Lorentz-invariance of distribution functions, discussing thermal background radiation, proton spectra, etc
Forman, M. A.↗
Analytic approximations for curves of growth of Doppler-Lorentz broadened lines
Analytic approximations in closed form for curves of growth of Doppler-Lorentz broadened lines, considering radiative transport in nonisotropic gases
Hansen, C. F.↗
Theoretical frameworks for testing relativistic gravity. III - Conservation laws, Lorentz invariance, and values of the PPN parameters
Lorentz invariant theory for relativistic gravity testing, deriving conservation laws and parameter constraints from parametrized post-Newtonian equations of motion
Will, C. M.↗
Lorentz-invariant formulation of Cherenkov radiation by tachyons
Previous treatments of Cherenkov radiation, electromagnetic and gravitational, by tachyons were in error because the prescription employed to cut off the divergent integral over frequency is not a Lorentz invariant procedure. The resulting equation of motion for the tachyon is therefore not covariant. The proper procedure requires an extended, deformable distribution of charge or mass and yields a particularly simple form for the tachyon's world line, one that could be deduced from simple invariance considerations. It is shown that Cherenkov radiation by tachyons implys their ultimate annihilation with an antitachyon and demonstrates a disturbing property of tachyons, namely the impossibility of specifying arbitrary Cauchy data even in a purely classical theory.
Jones, F. C.↗
Lorentz transformations in the presence of a uniform gravitational field.
This article describes a Lorentz-like transformation between a fixed frame and an inertial frame that is free falling due to the presence of a uniform gravitation field. The application to the clock paradox problem and some connections with similar works are also discussed.
Broucke, R.↗
Methane absorption in the Jovian atmosphere. I - The Lorentz half-width in the 3nu/sub 3/ band at 1.1 micron.
The Lorentz half-width alpha (L), of the fine-structure components of the methane 3nu/sub 3/ R-branch in the Jovian spectrum has been measured from photoelectric observations of the singlet R(1). Curves of growth for the 3nu/sub 3/ R-branch manifolds have been calculated, using the measured value of alpha (L) and assuming a reflecting-layer atmosphere. The Walker-Hayes (1967) equivalent widths have been reanalyzed for rotational temperature and methane abundance. The half-width derived here is significantly different from a similar measurement made by Farmer (1969). The source of the discrepancy remains obscure.
Bergstralh, J. T.↗
Extending the Lorentz transformation by characteristic coordinates
The problem considered is that of rectilinear motion with variable velocity. The paper gives, by an elementary construction, a system of coordinates which is conformal in a restricted region near the axis of the motion. In such coordinates the velocity of light remains invariant even for observers moving with variable velocity. By a particular choice of the scale relation the restricted conformal transformations can be made to reduce to the Lorentz transformation everywhere in the case of constant velocity and locally in the case of variable velocity.
Jones, R. T.↗
Lorentz forces on the dust in Jupiter's ring
The paths of dust particles in the Jovian ring are investigated using a numerical integration program, including the acceleration due to gravity and the Lorentz and drag accelerations arising from the motions of the charged dust through the Jovian plasma. It is determined that the orbit of a 2.5 micron radius spherical dust particle with a density of 2 g/cu cm -10V will become significantly perturbed. The ring will tend to warp northwards near 130-160 deg longitude, with the maximum excursion of the Jupiter ring grains equalling about 0.1 deg (consistent with a distance of 220 km above the equatorial plane). It is found that either the particles are larger or the voltages on them less than what has been determined by previous investigators, while the plasma near the ring may be considerably cooler than was estimated. Calculations show that particles of 0.3 micron with -10 V potentials are spread from 1.68-1.98 of the radius of Jupiter and inclined up to 7 deg out of the equatorial plane. The paths of these particles do not follow Keplerian orbits, and the particle positions are not symmetric about the equatorial plane. Particles of 0.4 micron radius have less asymmetric orbits than 0.3 micron particles, while particles less than 0.2 micron are perturbed into Jupiter cloudtops within a few tens of hours.
Consolmagno, G. J.↗
Lorentz-covariant dissipative Lagrangian systems
The concept of dissipative Hamiltonian system is converted to Lorentz-covariant form, with evolution generated jointly by two scalar functionals, the Lagrangian action and the global entropy. A bracket formulation yields the local covariant laws of energy-momentum conservation and of entropy production. The formalism is illustrated by a derivation of the covariant Landau kinetic equation.
Kaufman, A. N.↗
Shape of solitons in classically forbidden states - 'Lorentz expansion'
The shape of extended objects in classically forbidden regions is shown to undergo expansion analogous to Lorentz contraction of a relativistic body of finite velocities. The problem of two interacting Dirac particles moving in one dimension is solved explicitly and the results are generalized to soliton solutions of field theories. An estimate of the effect on tunneling rates is also given, including solitons in (CH)z.
Guinea, F.↗
A modified Lorentz theory as a test theory of special relativity
Attention has been given recently to a modified Lorentz theory (MLT) that is based on the generalized Galilean transformation. Some explicit formulas within the framework of MLT, dealing with the one-way velocity of light, slow-clock transport, and the Doppler effect are derived. A number of typical experiments are analyzed on this basis. Results indicate that the empirical equivalence between MLT and special relativity is still maintained to second order terms. The results of previous works that predict that the MLT might be distinguished from special relativity at the third order by Doppler centrifuge tests capable of a fractional frequency detection threshold of 10 to the -15th are confirmed.
Chang, T.↗
Dual properties of spacetime under an alternative Lorentz transformation
A coordinate time, t(A), with absolute synchronization is defined as an alternative fourth spatial coordinate for model universes with flat space-time, and the theoretical implications of t(A) are explored in detail. Particular attention is given to a t(A)-based reformulation of the Lorentz transformation, the generalized Galilean transformation, which is found to offer significant advantages in understanding special-relativistic phenomena such as length contraction, time dilation, and the interaction of objects with the physical vacuum. With respect to astrophysical observations of superluminal motion, it is shown that the problem of causality violation can be avoided; the theory also predicts that weak anisotropic effects may be detectable in the earth reference frame.
Chang, T.↗
Direct measurement of correlation functions in a lattice Lorentz gas
Simulations of a two-dimensional ballistic Lorentz gas on a lattice are reported. A moment-propagation technique allows direct measurements of the velocity correlation function and its moments with low relative errors for all times. The predicted 1/t-sq algebraic tails in the velocity correlation function are observed at all studied scatterer densities, unlike what has been reported for continuous systems. In the square lattice a fast oscillation is observed, consistent with the existence of staggered density modes. For the second-rank tensor correlation function, an extremely slow approach to the expected 1/t exp 3 tail is found.
Binder, P.-M.↗
Measurements of Lorentz air-broadening coefficients and relative intensities in the H2O-16 pure rotational and nu2 bands from long horizontal path atmospheric spectra
Lorentz air-broadening coefficients and relative intensities have been measured for forty-three lines in the pure rotational band and twenty lines in the nu2 band of H2O-16 between 800 and 1150/cm. The results were derived from analysis of nine 0.017/cm-resolution atmospheric absorption spectra recorded over horizontal paths of 0.5-1.5 km with the McMath Fourier transform spectrometer and main solar telescope operated on Kitt Peak by the National Solar Observatory. A nonlinear least-squares spectral fitting technique was used in the spectral analysis. The results are compared with previous measurements and calculations. In most cases, the measured pressure-broadening coefficients and intensities are significantly different from the values in the 1986 HITRAN line parameters compilation.
Rinsland, Curtis P.↗
A six degree-of-freedom Lorentz vibration isolator with nonlinear controller
The results of a phase 2 Small Business Innovation Research Program sponsored by MSFC are presented. Technology is developed for isolating acceleration sensitive microgravity experiments from structural vibration of a spacecraft, such as a space station. Two hardware articles are constructed: a six degree of freedom Lorentz force isolation and a one degree of freedom low acceleration testbed capable of tests at typical experiment accelerations.
Fenn, Ralph C.↗