Related papers: Radar echo, Doppler Effect and Radar detection in …
We consider a nearly free falling Earth satellite where atomic wave interferometers are tied to a telescope pointing towards a faraway star. They measure the acceleration and the rotation relatively to the local inertial frame. We calculate…
If an Unruh-DeWitt detector moves with a uniform acceleration in Fock-space vacuum, then the transition rate of the detector is proportional to the thermal spectrum. It is well known that the transition rate of the detector crucially…
A monochromatic linear source of light is rotated with certain angular frequency and when such light is analysed after reflection then a change of frequency or wavelength may be observed depending on the location of the observer. This…
Acceleration radiation - or Unruh radiation - the thermal radiation observed by an ever accelerating observer or detector, although having similarities to Hawking radiation, so far has proved extremely challenging to observe experimentally.…
The radar experiment connects the geometry of spacetime with an observers measurement of spatial length. We investigate the radar experiment on Finsler spacetimes which leads to a general definition of radar orthogonality and radar length.…
We derive the metric of an accelerating observer moving with non-constant proper acceleration in flat spacetime. With the exception of a limiting case representing a Rindler observer, there are no horizons. In our solution, observers can…
The physical phenomena seen by an observer are defined for a local inertial system that is subjective to the observer. Such a coordinate system is called a ``moving frame'' because it changes from time to time. However, unlike the Thomas…
This paper revisits the problems of estimating the position of an object moving in $n$ ($\geq 2$)-dimensional Euclidean space using velocity measurements and either direction or range measurements of one or multiple source points. The…
Usual uniformly accelerated frame, in Dray-'t Hooft spacetime, does not see the any quantum imprint on Unruh effect due to localised shock wave in Minkowski spacetime. Here we argue that such non-appearance of quantum memory is specific to…
The Unruh effect establishes a fundamental equivalence between acceleration and thermality by demonstrating that a uniformly accelerated ground-state detector undergoes excitation as if immersed in a thermal bath. In this paper, we…
In the framework of General Relativity we develop a method for analysis of the operation of the optical position meters in their photodetectors proper reference frames. These frames are non-inertial in general due to the action of external…
We study a type of an Unruh-DeWitt-like detector based on a vector rather than scalar field. This detector has two energy states and produces Larmor radiation when there is no energy gap between them. This setup indicates that Larmor…
We describe the Doppler effect between equally accelerated light source and observer under the special relativity. The proper accelerations are constant and parallel. An English version is available by request. - - - - - - - - - - - Ni…
The generalization of the Larmor radiation formula in gravitational fields and with accelerating observers was obtained by Hirayama and others. We verify a special case of their result by explicit computation using a family of displaced…
We present an approach for radar-inertial odometry which uses a continuous-time framework to fuse measurements from multiple automotive radars and an inertial measurement unit (IMU). Adverse weather conditions do not have a significant…
This paper presents a radar odometry method that combines probabilistic trajectory estimation and deep learned features without needing groundtruth pose information. The feature network is trained unsupervised, using only the on-board radar…
A coordinate system is constructed for a general accelerating observer in 1+1 dimensions, and is used to determine the particle density of the massless Dirac vacuum for that observer. Equations are obtained for the spatial distribution and…
Assuming that an accelerated observer with four-velocity ${\bf u}_{\rm R}$ in a curved spacetime attributes the standard Bekenstein-Hawking entropy and Unruh temperature to his "local Rindler horizon", we show that the $\rm \it change$ in…
An uniformly accelerated observer can build his proper system of coordinates in a delimited sector of the flat Minkowski spacetime. The properties of the position and time coordinate lines for such an observer are studied and compared with…
We give a rigorous derivation of the general-relativistic formula for the two-way Doppler tracking of a spacecraft in Friedmann-Lemaitre-Robertson-Walker and in McVittie spacetimes. The leading order corrections of the so-determined…