Results 61 to 70 of about 1,179 (183)

Axion Black Hole Solution in Non‐Metricity Gravity

Fortschritte der Physik, Volume 74, Issue 2, February 2026.
Abstract A static, spherically symmetric black hole solution in symmetric teleparallel (non‐metricity) gravity sourced by an axion field is constructed. Starting from the modified field equations, exact configurations are obtained characterized by the mass M$M$ and an axion–geometry coupling β$\beta$, with temporal metric function A(r)=1−2Mr+βr$A(r)=1-\
A. Eid, G.G.L. Nashed
wiley   +1 more source

Gradient Ricci Bourguignon solitons on perfect fluid space-times [PDF]

Journal of Mahani Mathematical Research
The main purpose of the present paper is about characterizing the properties of the perfect fluid space-time that admits the gradient Ricci-Bourguignon soliton. This gives some results about the stability of the energy-momentum tensor and also under some
Sakineh Hajiaghasi, Shahroud Azami
doaj   +1 more source

A complex network perspective on brain disease

Biological Reviews, Volume 101, Issue 1, Page 364-399, February 2026.
ABSTRACT If brain anatomy and dynamics have a complex network structure as it has become standard to posit, it is reasonable to assume that such a structure should play a key role not only in brain function but also in brain dysfunction. However, exactly how network structure is implicated in brain damage and whether at least some pathologies can be ...
David Papo, Javier M. Buldú
wiley   +1 more source

Witten genera of complete intersections

Bulletin of the London Mathematical Society, Volume 58, Issue 2, February 2026.
Abstract We prove vanishing results for Witten genera of string generalized complete intersections in homogeneous Spinc$\text{Spin}^c$‐manifolds and in other Spinc$\text{Spin}^c$‐manifolds with Lie group actions. By applying these results to Fano manifolds with second Betti number equal to one we get new evidence for a conjecture of Stolz.
Michael Wiemeler
wiley   +1 more source

The Long-Time Behavior of the Ricci Tensor under the Ricci Flow [PDF]

Geometry, 2013
We show that, given an immortal solution to the Ricci flow on a closed manifold with uniformly bounded curvature and diameter, the Ricci tensor goes to zero as . We also show that if there exists an immortal solution on a closed 3-dimensional manifold such that the product of the curvature and the square of the diameter is uniformly bounded, then this ...
openaire   +2 more sources

The cosymplectic Chern–Hamilton conjecture

Journal of the London Mathematical Society, Volume 113, Issue 2, February 2026.
Abstract In this paper, we study the Chern–Hamilton energy functional on compact cosymplectic manifolds, fully classifying in dimension 3 those manifolds admitting a critical compatible metric for this functional. This is the case if and only if either the manifold is co‐Kähler or if it is a mapping torus of the 2‐torus by a hyperbolic toral ...
Søren Dyhr, Ángel González‐Prieto, Eva Miranda, Daniel Peralta‐Salas   +3 more
wiley   +1 more source

Axially Symmetric-dS Solution in Teleparallel f(T) Gravity Theories

Advances in High Energy Physics, 2015
We apply a tetrad field with six unknown functions to Einstein field equations. Exact vacuum solution, which represents axially symmetric-dS spacetime, is derived.
Gamal G. L. Nashed
doaj   +1 more source

Curvature tensor under the Ricci flow [PDF]

American Journal of Mathematics, 2005
Consider the unnormalized Ricci flow ( g ij ) t = -2 R ij for t ∈ [0, T ), where T < ∞. Richard Hamilton showed that if the curvature operator is uniformly bounded under the flow for all times t ∈ [0, T ), then the solution can be extended beyond T . We prove that if the Ricci curvature is uniformly bounded under the flow for all times t ∈ [0, T ),
openaire   +2 more sources

More Than Regulation: Challenging Habermas on the Future of the Public Sphere

Journal of Social Philosophy, EarlyView.
Bernardo Ferro
wiley   +1 more source

Stimuli‐Responsive Chemical Systems That Mimic Biological Dynamics

Chemistry – A European Journal, Volume 32, Issue 1, 2 January 2026.
Chemists are designing synthetic systems that mimic life's dynamic behaviors, such as motion, sensing, adaptation, and compartmentalization, by integrating reaction networks with stimuli like light, pH, and chemical fuels. This mini‐review surveys molecular machines, responsive materials, nucleic acid networks, and artificial cells, highlighting how ...
Antonio Aguanell, Álvaro Sarabia‐Vallejo, Marc Hennebelle, Ruth Pérez‐Fernández   +3 more
wiley   +1 more source