Results 81 to 90 of about 455,834 (341)
Gravitational properties of light—the gravitational field of a laser pulse
New Journal of Physics, 2016 The gravitational field of a laser pulse of finite lifetime, is investigated in the framework of linearized gravity. Although the effects are very small, they may be of fundamental physical interest. It is shown that the gravitational field of a linearly
Dennis Rätzel +2 more
doaj +1 more source
Quantum mechanics and the equivalence principle
, 2004 A quantum particle moving in a gravitational field may penetrate the classically forbidden region of the gravitational potential. This raises the question of whether the time of flight of a quantum particle in a gravitational field might deviate ...
Davies, P. C. W.
core +1 more source
Gravitational collapse of vacuum gravitational field configurations
Journal of Mathematical Physics, 1995 This paper proves a theorem about the existence of an apparent horizon in general relativity, which applies equally well to vacuum configurations and matter configurations. The theorem uses the reciprocal of the surface-to-volume ratio of a region on a space slice to measure the radius of the region, and uses the minimum value Kmin of certain ...
openaire +2 more sources
Multidirectional Motion Strategy of Miniature Water Surface Robot Actuated by Single Exciter
Advanced Robotics Research, EarlyView.A novel multidirectional motion strategy on the water surface based on a single exciter is proposed, and a single‐exciter single‐plate module is developed for actuation. The driving forces generation mechanism of the module is revealed from the perspective of the asymmetric surface wave field.
Haoxuan He +4 more
wiley +1 more source
Is equivalence principle valid for quantum gravitational field?
Results in PhysicsEntanglement can be generated through the gravitational interaction between two massive bodies that are initially in a product state. This shows that the gravitational field is quantum.
Baocheng Zhang
doaj +1 more source
On Nearly Newtonian Potentials and Their Implications to Astrophysics
Galaxies, 2018 We review the concept of the slow motion problem in General relativity. We discuss how the understanding of this process may imprint influence on the explanation of astrophysical ...
Abraao J. S. Capistrano
doaj +1 more source
Poincar\'{e} gauge theory of gravity
, 1993 A Poincar\'{e} gauge theory of (2+1)-dimensional gravity is developed. Fundamental gravitational field variables are dreibein fields and Lorentz gauge potentials, and the theory is underlain with the Riemann-Cartan space-time.
A. Hosoya +18 more
core +2 more sources
TreeSpider: In‐Canopy Exploration With Tether‐Based Aerial Modular Arms
Advanced Robotics Research, EarlyView.A tethered drone with perching arms and a 360° ring enables unprecedented maneuverability within dense forest canopies. By dynamically adjusting tether length and decoupling pitch from the frame, it navigates between branches, senses multiple trees, and interacts physically with foliage.
Luca Romanello +7 more
wiley +1 more source
Attitude Estimation of Underwater Vehicles Using Field Measurements and Bias Compensation
Sensors, 2019 This paper proposes a method of estimating the attitude of an underwater vehicle. The proposed method uses two field measurements, namely, a gravitational field and a magnetic field represented in terms of vectors in three-dimensional space.
Nak Yong Ko +3 more
doaj +1 more source
Advanced Robotics Research, EarlyView.This review identifies key design considerations for insect‐inspired microrobots capable of multimodal locomotion. To draw inspiration, biological and robotic strategies for moving in air, on water surfaces, and underwater are examined, along with approaches for crossing the air–water interface.
Mija Jovchevska +2 more
wiley +1 more source