Results 11 to 20 of about 11,436 (251)
Intrinsic torsion, extrinsic torsion, and the Hubble parameter
Classical and Quantum GravityAbstract We study the intrinsic and extrinsic torsions (defined by analogy with the intrinsic and extrinsic curvatures) of the spatial sections of torsional spacetimes. We consider two possibilities. First, that the intrinsic torsion might prove to be directly observable.
exaly +3 more sources
Evolutions of partner-ruled surfaces with simultaneous inextensibility conditions. [PDF]
PLoS ONERuled surfaces are a class of surfaces generated by a moving straight line and are used in various design and modeling applications, including kinematics, robotics, and computer-aided geometric design.
Kemal Eren +2 more
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Einstein metrics via intrinsic or parallel torsion [PDF]
Mathematische Zeitschrift, 2004 The classification of Riemannian manifolds by the holonomy group of their Levi-Civita connection picks out many interesting classes of structures, several of which are solutions to the Einstein equations. The classification has two parts. The first consists of isolated examples: the Riemannian symmetric spaces.
Cleyton, R., Swann, Andrew
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Cosmological hyperfluids, torsion and non-metricity
European Physical Journal C: Particles and Fields, 2020 We develop a novel model for cosmological hyperfluids, that is fluids with intrinsic hypermomentum that induce spacetime torsion and non-metricity. Imposing the cosmological principle to metric-affine spaces, we present the most general covariant form of
Damianos Iosifidis
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Invariant torsion and G2-metrics
Complex Manifolds, 2015 We introduce and study a notion of invariant intrinsic torsion geometrywhich appears, for instance, in connection with the Bryant-Salamon metric on the spinor bundle over S3. This space is foliated by sixdimensional hypersurfaces, each of which carries a
Conti Diego, Madsen Thomas Bruun
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Current State of Computational Modeling of Nanohelicenes
Nanomaterials, 2023 This review considers the works that focus on various aspects of the theoretical description of nanohelicenes (other equivalent names are graphene spirals, graphene helicoid, helical graphene nanoribbon, or helical graphene)—a promising class of one ...
Vitaly V. Porsev, Robert A. Evarestov
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THE INTRINSIC TORSION OF SU(3) AND G2 STRUCTURES [PDF]
Differential Geometry, Valencia 2001, 2002 We analyse the relationship between the components of the intrinsic torsion of an SU(3) structure on a 6-manifold and a G_2 structure on a 7-manifold. Various examples illustrate the type of SU(3) structure that can arise as a reduction of a metric with holonomy G_2.
Chiossi, Simon, Salamon, Simon
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Direct Observation of the Intrinsic Backbone Torsional Mobility of Disordered Proteins [PDF]
Biophysical Journal, 2016 The fundamental backbone dynamics of unfolded proteins arising due to intrinsic ϕ-ψ dihedral angle fluctuations dictate the course of protein folding, binding, assembly, and function. These internal fluctuations are also critical for protein misfolding associated with a range of human diseases.
Neha, Jain +6 more
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Intrinsic torsion in quaternionic contact geometry [PDF]
ANNALI SCUOLA NORMALE SUPERIORE - CLASSE DI SCIENZE, 2016 We investigate quaternionic contact (qc) manifolds from the point of view of intrinsic torsion. We argue that the natural structure group for this geometry is a non-compact Lie group K containing Sp(n)H^*, and show that any qc structure gives rise to a canonical K-structure with constant intrinsic torsion, except in seven dimensions, when this ...
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Harmonic almost contact structures via the intrinsic torsion [PDF]
Israel Journal of Mathematics, 2011 31 ...
González-Dávila, J. C. +1 more
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