Local group velocity and path-delay: semi-classical propagators for the time evolution of Wigner functions in deep tunneling and in dispersive media

2004 ◽  
Vol 396 (4-6) ◽  
pp. 261-267
Author(s):  
S. Kallush ◽  
E. Tannenbaum ◽  
Bilha Segev
1983 ◽  
Vol 6 ◽  
pp. 269-282 ◽  
Author(s):  
M. Aaronson

AbstractThe Tully-Fisher relation applied in the infrared appears to be the best global distance indicator presently available for determining the expansion rate and deviations from uniform Hubble flow. In this article recent results obtained using the IR/H I method are reviewed. A Virgo-directed Local Group velocity of about 300 km s–1 is indicated (implying a local value for the deceleration parameter qo ~ 0.05 – 0.1) along with a “best guess” value for the Hubble Constant of 85 km s-1 Mpc-1.


2011 ◽  
Vol 25 (16) ◽  
pp. 1401-1415 ◽  
Author(s):  
KUN SI ◽  
NING-LI ZHU ◽  
HUAN-YU JIA

The Wigner functions of the Fock states and their superposition states have negative value clearly. We focus on discussing the time evolution of the Fock states and their superposition states by the Wigner function under the coherent drive (pumping laser) and dissipation channels (cavity radiation). The results show that the negative region of their Wigner function gradually diminishes as the time kt or the gain coefficient g increasing. In addition, the disappearing time is related to the value of g - k. The loss of non-classical features becomes slower when g increases with the k > g; there is the "frozen zone" when k = g; then the loss of non-classical features becomes faster when g increases with k < g.


2004 ◽  
Vol 21 (4) ◽  
pp. 415-417 ◽  
Author(s):  
Kenton J. D'Mellow ◽  
Will Saunders ◽  

AbstractWe present a brief overview and preliminary measure of the Local Group velocity, using the PSCz survey together with its recently completed extension into the Galactic plane, the Behind The Plane (BTP) survey. The addition of the BTP has increased the total sky coverage from 84% to 93%, drastically reducing the systematic uncertainty in the direction of the local gravitational pull caused by incomplete sky coverage. We present methods that self-consistently determine the acceleration in the presence of redshift distortions. Preliminary results suggest that the dipole converges within the survey limiting depth. There is a large, but only marginally significant, component to the dipole arising at 180–200 h–1 Mpc.


1993 ◽  
Vol 48 (5) ◽  
pp. 3890-3894 ◽  
Author(s):  
Eric L. Bolda ◽  
Raymond Y. Chiao ◽  
John C. Garrison

The paper describes the details of a repetition of the Jones-Richards experiment (1954) to compare the recoil of a mirror due to the radiation pressure of light striking it in an optically dense medium with the recoil of the same mirror from the same light in air. A more than tenfold improvement in precision has been possible through the development of the laser and of multilayer reflectors of high reflectivity and low absorption. The new experiment confirms, to a precision of about 0.05 %, that the momentum associated with electromagnetic radiation increases directly with the refractive index of the medium into which it passes, discriminating substantially in favour of the phase velocity ratio and against the group velocity ratio. The experiment also shows that the magnitude of recoil of a mirror in oblique incidence does not vary, within the foregoing precision, when the plane of polarization is changed from perpendicular to parallel to the plane of incidence.


2021 ◽  
Vol 2 (3) ◽  
pp. 183-199
Author(s):  
Özcan Çakır ◽  
Nart Coşkun

We numerically simulate the field measurements of Rayleigh surface waves and electrical resistivity in which the target depth is set to be less than 50-m. The Rayleigh surface waves are simulated in terms of fundamental mode group and phase velocities. The seismic field data is assumed to be collected through a conventional shot-gather. The group velocities are found from the application of the multiple filter technique in a single-station fashion while for the phase velocities the slant stacking, or linear radon transform are applied in fashion of multichannel analysis of surface waves (MASW). The average seismic structure from the source to the receiver (or geophone) is represented by the group velocity curve while the average seismic structure underneath the geophone array is represented by the phase velocity curve. The single-station group velocity curves are transformed into local group velocity curves by setting a linear system through grid points. The shear-wave velocity cross section underneath the examined area is constructed by inverting these local group velocity curves. The electrical resistivity structure of the underground is similarly studied. The field compilation of the resistivity data is assumed to be completed by the application of the multiple electrode Pole-Pole array. The actual resistivity assemble underneath the analyzed area is inverted by considering the apparent (measured) resistivity values. Unique forms such as ore body, cavity, sinkhole, melt, salt, and fluid within the Earth may be examined by joint interpretation of electrical resistivities and seismic velocities. These formations may be better outlined by following their distinct signs such as high/low resistivities and high/low seismic velocities. Doi: 10.28991/HEF-2021-02-03-01 Full Text: PDF


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