Results 151 to 160 of about 707,832 (374)

Entropic force, running gravitational coupling and future singularities

, 2013
The effects of a running gravitational coupling and the entropic force on future singularities are considered. Although it is expected that the quantum corrections remove the future singularities or change the singularity type, treating the running ...
Abchouyeh, Maryam Aghaei, Mirza, Behrouz, Sherkatghanad, Zeinab   +2 more
core   +1 more source

Soft Robotic Snake with Tunable Undulatory Gait for Efficient Underwater Locomotion

Advanced Robotics Research, EarlyView.
This study designs an underwater soft snake robot using 3D‐printed soft actuators, controlled by specific signals to generate sinusoidal undulation. Results show a positive correlation between speed and swing amplitude, with optimal performance at 2/3π phase offset, PLA tail, 1.2 voltage growth rate, and 6s undulation period achieving a maximum speed ...
Huichen Ma, Junjie Zhou, Raye Yeow
wiley   +1 more source

Correlation functions at the bulk point singularity from the gravitational eikonal S-matrix

Journal of High Energy Physics, 2019
The bulk point singularity limit of conformal correlation functions in Lorentzian signature acts as a microscope to look into local bulk physics in AdS.
Carlos Cardona
doaj   +1 more source

Applications of singularity theory to gravitational lensing. I. Multiple lens planes [PDF]

, 1993
Harold Levine, A. O. Petters, J. Wambsganß   +2 more
openalex   +1 more source

A characterization of the central shell-focusing singularity in spherical gravitational collapse

, 1999
We give a characterization of the central shell-focusing curvature singularity that can form in the spherical gravitational collapse of a bounded matter distribution obeying the dominant energy condition.
Christodoulou D, Hawking S W, Joshi P S, Joshi P S, Joshi P S, Joshi P S, Penrose R, Singh T P, Singh T P, Singh T P, Singh T P, Singh T P, Singh T P, T P Singh, Wald R M, Wald R M   +15 more
core   +1 more source

Hard‐Magnetic Soft Millirobots in Underactuated Systems

Advanced Robotics Research, EarlyView.
This review provides a comprehensive overview of hard‐magnetic soft millirobots in underactuated systems. It examines key advances in structural design, physics‐informed modeling, and control strategies, while highlighting the interplay among these domains.
Qiong Wang, Zixuan Zhang, Bingyan Li, Junkai Wang, Hongcheng Gu   +4 more
wiley   +1 more source

Gravitational axial perturbations and quasinormal modes of loop quantum black holes

European Physical Journal C: Particles and Fields, 2019
Loop quantum gravity (LQG) is a theory that proposes a way to model the behavior of the spacetime in situations where its atomic characteristic arises. Among these situations, the spacetime behavior near the Big Bang or black hole’s singularity.
M. B. Cruz, C. A. S. Silva, F. A. Brito
doaj   +1 more source

A no-singularity scenario in loop quantum gravity

, 2012
Canonical methods allow the derivation of effective gravitational actions from the behavior of space-time deformations reflecting general covariance.
Ashtekar A, Ashtekar A, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Cailleteau T Mielczarek J Barrau A Grain J, Date G, George M Paily, Henderson A Laddha A Tomlin C, Kreienbuehl A, Martin Bojowald, Perez A, Rendall A D, Reyes J D, Rovelli C, Rovelli C, Thiemann T, Thiemann T   +23 more
core   +1 more source

Magnetic Field Driven Microrobot Based on Hydrogels

Advanced Robotics Research, EarlyView.
Hydrogel‐based magnetic microrobots synergize remote magnetic control with the biocompatibility of flexible hydrogels, emerging as promising tools for minimally invasive biomedicine. This enables remotely controllable, untethered navigation within complex biological microenvironments.
Juncai Song, Yubing Guo
wiley   +1 more source

Multimodal Locomotion in Insect‐Inspired Microrobots: A Review of Strategies for Aerial, Surface, Aquatic, and Interfacial Motion

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, Kaushik Jayaram, Nicole Xu   +2 more
wiley   +1 more source