Results 101 to 110 of about 167,529,233 (288)
ACT data and positive running of the spectral index for scalar theory and modified gravity
Physics Letters BIn this work we address the possibility of having a positive running of the spectral index in inflationary theories. The recent ACT data indicate mildly that the running of the spectral index might be positive, and several other physical indications ...
S.D. Odintsov, V.K. Oikonomou
doaj +1 more source
Asymmetry in Skipping Enhances Viability Against Control Input Noise
Advanced Robotics Research, EarlyView.Quadruped animals use asymmetric galloping gaits at high speeds, yet the functional role of this asymmetry remains unclear. This study shows that left–right asymmetry in touchdown angles enhances robustness to control noise. Using a simple two‐legged locomotion model and viability theory, it demonstrates that asymmetric skipping substantially enlarges ...
Yuichi Ambe, Alvin So, Shinya Aoi
wiley +1 more source
Inconsistency of modified gravity in cosmology
Physics Letters BWe show that there is a fundamental flaw in the application of modified gravity theories in cosmology, taking f(R) gravity as a paradigmatic example. This theory contains a scalar degree of freedom that couples to the matter stress-energy tensor but not ...
Pablo A. Cano
doaj +1 more source
EPJ Web of Conferences, 2018 The current accelerating expansion of the Universe is explained either by dark energy or by modified gravity theories. Both of them can explain exactly the same background evolution of the Universe, however this degeneracy may be broken when the ...
Hyun Young-Hwan +2 more
doaj +1 more source
Gravity's rainbow: A bridge between LQC and DSR
Physics Letters B, 2017 The doubly special relativity (DSR) theories are constructed in order to take into account an observer-independent length scale in special relativity framework. Gravity's rainbow is a simple generalization of DSR theories to incorporate gravity.
M.A. Gorji, K. Nozari, B. Vakili
doaj +1 more source
Continuum Mechanics Modeling of Flexible Spring Joints in Surgical Robots
Advanced Robotics Research, EarlyView.A new mechanical model of a tendon‐actuated helical extension spring joint in surgical robots is built using Cosserat rod theory. The model can implicitly handle the unknown contacts between adjacent coils and numerically predict spring shapes from straight to significantly bent under actuation forces.
Botian Sun +3 more
wiley +1 more source
Modified Theories of Gravity [PDF]
, 2020 Ali Chamseddine (Advisor); Constantin Bachas (Chair, directeur de recherche, CNRS-ENS, Paris); Prof. Viatcheslav Mukhanov (Ludwig Maximilian University of Munich); Jihad Touma (AUB); Mounib El Eid (AUB)This dissertation is composed of three parts.
Saghir, Chireen Ahmad
core
Origami‐Inspired Structural Design for Aquatic‐Terrestrial Amphibious Robots
Advanced Robotics Research, EarlyView.This work presents a lightweight amphibious origami robot actuated by a single shape memory alloy wire. A rigid foldable origami structure with displacement amplification enables efficient terrestrial crawling and aquatic swimming. The addition of fan‐shaped units allows controllable turning in both environments.
Weiqi Liu +5 more
wiley +1 more source
Time delay predictions in a modified gravity theory [PDF]
Classical and Quantum Gravity, 2006 5 pages, LaTex file, no figures.
openaire +2 more sources
A Soft Robotic Fish With a Dielectric Elastomer Actuator Body and Negative Stiffness Spine
Advanced Robotics Research, EarlyView.This work introduces a bio‐mimetic soft robotic fish driven by fiber‐reinforced dielectric elastomer actuators integrated as its body. By prestretching this active skin against a flexible spine, a negative stiffness system is created, enabling large‐amplitude bending.
Markus Koenigsdorff +4 more
wiley +1 more source