Results 71 to 80 of about 1,099 (217)

Counting Degrees of Freedom: A Method Applicable From Scalars to f(Q)$f(\mathbb {Q})$ Gravity and Beyond

Fortschritte der Physik, Volume 74, Issue 6, June 2026.
ABSTRACT We present a clear, step‐by‐step method for counting degrees of freedom and identifying constraints in general field theories. This approach, grounded in the works of Einstein, Hilbert, Cartan, Kuranishi, and, more recently, Seiler, is neither Lagrangian nor Hamiltonian in nature. Instead, it applies directly to the field equations. We offer a
Lavinia Heisenberg
wiley   +1 more source

Analytic Matrix Method for Frequency Response Techniques Applied to Nonlinear Dynamical Systems I: Small and Medium Amplitude Oscillations

Mathematics, 2021
This is the first on a series of articles that deal with nonlinear dynamical systems under oscillatory input that may exhibit harmonic and non-harmonic frequencies and possibly complex behavior in the form of chaos.
Elena Hernandez, Octavio Manero, Fernando Bautista, Juan Paulo Garcia-Sandoval   +3 more
doaj   +1 more source

On the tightness of left‐invariant contact structures

Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.
Abstract We prove that all left‐invariant contact structures on three‐dimensional Lie groups are tight. The argument is based on Riemannian methods and establishes a unique factorization property for any Lie group admitting a left‐invariant contact structure, other than SU(2)$\mathrm{SU}(2)$. We then make use of such factorization property to construct
Eugenio Bellini
wiley   +1 more source

Invariant submanifolds of conformal symplectic dynamics

Journal de l’École polytechnique — Mathématiques
We study invariant manifolds of conformal symplectic dynamical systems on a symplectic manifold ( ℳ , ω )
Arnaud, Marie-Claude, Féjoz, Jacques
openaire   +4 more sources

Cohomogeneity‐one solitons in Laplacian flow: Local, smoothly‐closing and steady solitons

Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.
Abstract We initiate a systematic study of cohomogeneity‐one solitons in Bryant's Laplacian flow of closed G2$\text{G}_2$‐structures on a 7‐manifold, motivated by the problem of understanding finite‐time singularities of that flow. Here, we focus on solitons with symmetry groups Sp(2)${\rm Sp}(2)$ and SU(3)${\rm SU}(3)$; in both cases, we prove the ...
Mark Haskins, Johannes Nordström
wiley   +1 more source

Semi-Invariant Submanifolds of Almost $\alpha$-Cosymplectic $f$-Manifolds

Communications in Advanced Mathematical Sciences, 2020
In this paper, we have and study several properties of semi-invariant submanifolds of an almost $\alpha$-cosymplectic $f$-manifold. We give an example and investigate the integrability conditions for the distributions involved in the definition of a semi-
Ali İhsan Sivridağ, Selahattin Beyendi, Nesip Aktan   +2 more
doaj  

Standing waves of nonlinear Schrödinger systems with all attractive forces

Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.
Abstract Since the pioneering work of Lin and Wei on nonlinear Schrödinger systems of n$n$ components with interaction forces aij$a_{ij}$ between the i$i$‐th and j$j$‐th components for 1⩽i,j⩽n$1\leqslant i,j\leqslant n$, there have been numerous further developments in many directions. However, even in the simplest case where all interaction forces are
Jaeyoung Byeon
wiley   +1 more source

ANTI-INVARIANT SUBMANIFOLDS OF A NORMAL PARACONTACT METRIC MANIFOLD

, 2021
In this paper, anti-invariant submanifolds of a normal paracontact metric manifold are studied and characterizing the submanifold with respect to covariant derivative of the second fundamental form of anti-invariant sub-manifold.
Dirik S., Atçeken M., Yildirim Ü.
core   +1 more source

Isotopy and equivalence of knots in 3‐manifolds

Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.
Abstract Two knots K$K$ and J$J$ in S3$S^3$ are isotopic if and only if they are related by an orientation‐preserving diffeomorphism of S3$S^3$. This claim follows from the fact that any orientation‐preserving self‐diffeomorphism of S3$S^3$ is isotopic to the identity. We show that this same idea applies to any prime oriented closed 3‐manifold.
Paolo Aceto, Corey Bregman, Christopher W. Davis, JungHwan Park, Arunima Ray   +4 more
wiley   +1 more source

Pseudoparallel Invariant Submanifolds of a Para-Sasakian Manifold

, 2023
In this paper, invariant submanifolds of a para-Sasakian manifold have been studied. Some special submanifolds such as pseudoparallel, 2-pseudoparallel, Ricci generalized pseudoparallel, and 2-Ricci generalized pseudoparallel submanifolds of a para ...
Mert, Tuğba, Atçeken, Mehmet
core   +1 more source