English
Related papers

Related papers: On Coordinate Frames in Axisymmetric Static Vacuum…

200 papers

A Reference is corrected. (We derive the Fermi coordinate system of an observer in arbitrary motion in an arbitrary weak gravitational field valid to all orders in the geodesic distance from the worldline of the observer. In flat space-time…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Karl-Peter Marzlin

We study the kinematic relative velocity of general test particles with respect to stationary observers (using spherical coordinates) in Schwarzschild spacetime, obtaining that its modulus does not depend on the observer, unlike Fermi,…

General Relativity and Quantum Cosmology · Physics 2013-01-24 Vicente J. Bolós

Modelling interactions is critical in learning complex dynamical systems, namely systems of interacting objects with highly non-linear and time-dependent behaviour. A large class of such systems can be formalized as $\textit{geometric…

Machine Learning · Computer Science 2024-03-21 Miltiadis Kofinas , Naveen Shankar Nagaraja , Efstratios Gavves

Observations of the large-scale structure (LSS) implicitly assume an ideal FLRW observer with the ambient structure having no influence on the observer. However, due to correlations in the LSS, cosmological observables are dependent on the…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-05 Robert Reischke , Björn malte Schäfer , Krzysztof Bolejko , Geraint F. Lewis , Max Lautsch

We study the non-relativistic limit of quantum fields for an inertial and a non-inertial observer. We show that non-relativistic particle states appear as a superposition of relativistic and non-relativistic particles in different frames.…

High Energy Physics - Theory · Physics 2023-06-06 Riccardo Falcone , Claudio Conti

We analyze a technique of obtaining turbulence power spectrum using spectral line data along the velocity coordinate, which we refer to as Velocity Coordinate Spectrum (VCS). We formalize geometrical aspects of observation through a single…

Astrophysics · Physics 2007-05-23 A. Chepurnov , A. Lazarian

In this manuscript, we consider a scenario in which a spin-1/2 quanton goes through a superposition of co-rotating and counter-rotating geodetic circular paths, which play the role of the paths of a Mach-Zehnder interferometer in a…

General Relativity and Quantum Cosmology · Physics 2021-07-23 Marcos L. W. Basso , Jonas Maziero

In an anisotropic universe, observers not positioned at a point of special symmetry should observe cosmic parallax - the relative angular motion of test galaxies over cosmic time. It was recently argued that the non-observance of this…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-30 Michele Fontanini , Mark Trodden , Eric J. West

This paper explores the observability and estimation capability of dynamical systems using predominantly relative measurements of the system's state-space variables, with minimal to no reliance on absolute measurements of these variables.…

Systems and Control · Electrical Eng. & Systems 2024-10-29 Ioannis Raptis

The relativistic conception of space and time is challenged by the quantum nature of physical observables. It has been known for a long time that Poincar\'e symmetry of field theory can be extended to the larger conformal symmetry. We use…

Quantum Physics · Physics 2013-02-27 Marc-Thierry Jaekel , Serge Reynaud

Most Simultaneous localisation and mapping (SLAM) systems have traditionally assumed a static world, which does not align with real-world scenarios. To enable robots to safely navigate and plan in dynamic environments, it is essential to…

Robotics · Computer Science 2024-10-01 Jesse Morris , Yiduo Wang , Viorela Ila

We consider the general form of the linear transformation for point rotation coordinate frames. The frames have the rotation axis at every point. In the transformation the frequency of one frame relative to another is not equivalent to the…

Optics · Physics 2007-05-23 Boris V. Gisin

We propose a new framework of quantum field theory for an arbitrary observer in curved spacetime, defined in the spacetime region in which each point can both receive a signal from and send a signal to the observer. Multiple motivations for…

General Relativity and Quantum Cosmology · Physics 2009-07-16 Hui Yao

Geodesic completeness is typically regarded as a basic criterion to determine whether a given spacetime is regular or singular. However, the principle of general covariance does not privilege any family of observers over the others and,…

General Relativity and Quantum Cosmology · Physics 2018-03-14 Gonzalo J. Olmo , Diego Rubiera-Garcia , Antonio Sanchez-Puente

We investigate how deformations of special relativity in momentum space can be extended to position space in a consistent way, such that the dimensionless contraction between wave-vector and coordinate-vector remains invariant. By using a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Hossenfelder

Visual Simultaneous Localisation and Mapping (VSLAM) is a well-known problem in robotics with a large range of applications. This paper presents a novel approach to VSLAM by lifting the observer design to a novel Lie group on which the…

Systems and Control · Electrical Eng. & Systems 2026-01-19 Pieter van Goor , Robert Mahony , Tarek Hamel , Jochen Trumpf

The response of laser interferometers to gravitational waves has been calculated in a number of different ways, particularly in the transverse-traceless and the local Lorentz gauges. At first sight, it would appear that these calculations…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Malik Rakhmanov

When working around other agents such as humans, it is important to model their perception capabilities to predict and make sense of their behavior. In this work, we consider agents whose perception capabilities are determined by their…

Robotics · Computer Science 2025-08-12 Maulik Bhatt , HongHao Zhen , Monroe Kennedy , Negar Mehr

We introduce observables associated with the space-time position of a quantum point defined by the intersection of two light pulses. The time observable is canonically conjugated to the energy. Conformal symmetry of massless quantum fields…

Quantum Physics · Physics 2009-10-30 Marc-Thierry Jaekel , Serge Reynaud

Considering that a position measurement can effectively involve a momentum-dependent shift and rescaling of the "true" space-time coordinates, we construct a set of effective space-time coordinates which are naturally non-commutative. They…

High Energy Physics - Theory · Physics 2007-08-29 Florian Girelli , Etera R. Livine