Results 81 to 90 of about 178,359 (292)
Bounce Loop Quantum Cosmology Corrected Gauss-Bonnet Gravity
, 2015 We develop a Gauss-Bonnet extension of Loop Quantum Cosmology, by introducing holonomy corrections in modified $F(\mathcal{G})$ theories of gravity.
Haro, J. +4 more
core +2 more sources
Advanced Materials Technologies, EarlyView.This study formulated a 5Y‐PSZ zirconia paste for extrusion‐based additive manufacturing via direct ink writing, producing dense ceramic structures for dental applications. A colloidal approach with 47 vol% nanometric powder and tailored additives optimized rheology and printability.
Juliana de Freitas Gouveia Silva +5 more
wiley +1 more source
Currents and superpotentials in classical gauge theories: II. Global aspects and the example of affine gravity [PDF]
Classical and Quantum Gravity, 2000 The conserved charges associated to gauge symmetries are defined at a boundary component of space-time because the corresponding Noether current can be rewritten on-shell as the divergence of a superpotential. However, the latter is afflicted by ambiguities.
Julia, B., Silva, S.
openaire +3 more sources
A pilot study on canonical gravity with mass dimension one fermions
Journal of High Energy Physics, 2022 The mass dimension one (MDO) fermionic field is built on a complete set of dual-helicity eigenspinors of the charge conjugation operator, which obeys the statistic of Fermi-Dirac.
R. de C. Lima +2 more
doaj +1 more source
Quantum Gravity: Has Spacetime Quantum Properties? [PDF]
, 2009 The incompatibility between GR and QM is generally seen as a sufficient motivation for the development of a theory of Quantum Gravity. If - so a typical argumentation - QM gives a universally valid basis for the description of all natural systems, then ...
Hedrich, Reiner
core +1 more source
Noether Symmetries and Covariant Conservation Laws in Classical, Relativistic and Quantum Physics
, 2010 We review the Lagrangian formulation of Noether symmetries (as well as "generalized Noether symmetries") in the framework of Calculus of Variations in Jet Bundles, with a special attention to so-called "Natural Theories" and "Gauge-Natural Theories ...
Fatibene +11 more
core +2 more sources
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 +4 more
wiley +1 more source
Effective Theories of Classical Gravity
, 2012 AbstractIf the concepts underlying Effective Theory were appreciated from the earliest days of Newtonian gravity, Le Verrier’s announcement in 1845 of the anomalous perihelion precession of Mercury would have been no surprise. Furthermore, the size of the effect could have been anticipated through “naturalness” arguments well before the definitive ...
openaire +1 more source
Higher order gravities and the Strong Equivalence Principle
Journal of High Energy Physics, 2017 We show that, in all metric theories of gravity with a general covariant action, gravity couples to the gravitational energy-momentum tensor in the same way it couples to the matter energy-momentum tensor order by order in the weak field approximation ...
Tomás Ortín
doaj +1 more source
Viability of vector-tensor theories of gravity
, 2009 We present a detailed study of the viability of general vector-tensor theories of gravity in the presence of an arbitrary temporal background vector field.
+9 more
core +1 more source