A common belief about big-bang cosmology is that the cosmological redshift cannot be properly viewed as a Doppler shift (that is, as evidence for a recession velocity), but must instead be viewed in terms of the stretching of space. We argue that the most natural interpretation of the redshift is in fact as a Doppler shift, or rather as the accumulation of many infinitesimal Doppler shifts. The...

It is well established that light carrying orbital angular momentum (OAM) can be used to induce a mechanical torque causing an object to spin. We consider the complementary scenario: will an observer spinning relative to the beam axis measure a change in OAM as a result of their rotational velocity? Remarkably, although a linear Doppler shift changes the linear momentum of a photon, the angular...

Frictional characteristics of a small aerostatic linear bearing are accurately evaluated by means of a method, in which the force acting on the moving part of the bearing is measured as the inertial force. An optical interferometer is newly developed to measure the Doppler shift frequency of the laser light reflected on the small moving part. From the measured time-varying Doppler shift frequen...

The performance of the 1.5-mm pulsed Doppler lidar, operated by the U.K. Universities Facility for Atmospheric Measurement (UFAM) over a 51-day continuous and unattended field deployment in southern England, is described and analyzed with a view to demonstrating the capabilities of the system for remote measurements of aerosols and velocities in the boundary layer. A statistical assessment of t...

Laser spectroscopy in the linear regime of radiation-matter interaction is a powerful tool for measuring thermodynamic quantities in a gas at thermodynamic equilibrium. In particular, the Doppler effect can be considered a gift of nature, linking the thermal energy to an optical frequency, namely the line centre frequency of an atomic or molecular spectral line. This is the basis of a relativel...

The spectrum profile that emerges in molecular spectroscopy and atmospheric radiative transfer as the combined effect of Doppler and pressure broadenings is known as the Voigt profile function. Because of its convolution integral representation, the Voigt profile can be interpreted as the probability density function of the sum of two independent random variables with Gaussian density (due to t...

Erkrankungen des Herz -Kreislaufsystems sind eine der häufigsten Todesursachen in hochentwickelten Gesellschaften. Entsprechend hoch ist das medizinische Interesse an geeigneten, möglichst quantitativen Diagnosemöglichkeiten. Die transösophageale, dreidimensionale Doppler -Echokardiographie verspricht gegenüber anderen Verfa hren genauere und schonendere Messungen diagnostischer Parameter. Zur ...

The class of Compact Steep-spectrum Sources is dominated by double-lobed objects (70%). The remaining 30% are jet-dominated objects, with the jet brightened either by Doppler boosting or by interaction with the ambient media. We show that there is both observational and statistical evidence in favour of an interaction between jets and dense gas clouds. Such an interaction should happen in the N...

This paper describes the recent developments in the modeling of the ICRF heating process in the VASIMR plasma using the EMIR code. The latest upgrade of the EMIR model involves a calculation of the parallel electric field component with a warm plasma conductivity model and considers the Doppler shift effect. The code now gives a much more accurate and a more physical solution than in the previo...