Results 11 to 20 of about 886 (48)
Homogeneous Riemannian Structures on Berger 3-Spheres [PDF]
13 pages.-- MSC2000 codes: 53C30, 53C25.The homogeneous Riemannian structures on the 3-dimensional Berger spheres, their corresponding reductive decompositions and the associated groups of isometries are obtained.
Grosshans, Frank D.+2 more
core +1 more source
Complex structures on the complexification of a real Lie algebra
Let g = a+b be a Lie algebra with a direct sum decomposition such that a and b are Lie subalgebras. Then, we can construct an integrable complex structure J̃ on h = ℝ(gℂ) from the decomposition, where ℝ(gℂ) is a real Lie algebra obtained from gℂby the ...
Yamada Takumi
doaj +1 more source
On the smallest Laplace eigenvalue for naturally reductive metrics on compact simple Lie groups [PDF]
Eldredge, Gordina and Saloff-Coste recently conjectured that, for a given compact connected Lie group $G$, there is a positive real number $C$ such that $\lambda_1(G,g)\operatorname{diam}(G,g)^2\leq C$ for all left-invariant metrics $g$ on $G$.
Lauret, Emilio Agustin
core +2 more sources
Isometry Lie algebras of indefinite homogeneous spaces of finite volume
Abstract Let g be a real finite‐dimensional Lie algebra equipped with a symmetric bilinear form ⟨·,·⟩. We assume that ⟨·,·⟩ is nil‐invariant. This means that every nilpotent operator in the smallest algebraic Lie subalgebra of endomorphisms containing the adjoint representation of g is an infinitesimal isometry for ⟨·,·⟩.
Oliver Baues+2 more
wiley +1 more source
Chern‐Simons forms of pseudo‐Riemannian homogeneity on the oscillator group
We consider forms of Chern‐Simons type associated to homogeneous pseudo‐Riemannian structures. The corresponding secondary classes are a measure of the lack of a homogeneous pseudo‐Riemannian space to be locally symmetric. In the present paper, we compute these forms for the oscillator group and the corresponding secondary classes of the compact ...
P. M. Gadea, J. A. Oubiña
wiley +1 more source
Ricci-flat and Einstein pseudoriemannian nilmanifolds
This is partly an expository paper, where the authors’ work on pseudoriemannian Einstein metrics on nilpotent Lie groups is reviewed. A new criterion is given for the existence of a diagonal Einstein metric on a nice nilpotent Lie group.
Conti Diego, Rossi Federico A.
doaj +1 more source
Topology and Integrability in Lagrangian Mechanics
This chapter reviews complete integrability in the setting of Lagrangian/Hamiltonian mechanics. It includes the construction of angle-action variables in illustrative examples, along with a proof of the Liouville-Arnol’d theorem.
L. Butler
semanticscholar +1 more source
Introduction to Grassmann manifolds and quantum computation
Geometrical aspects of quantum computing are reviewed elementarily for nonexperts and/or graduate students who are interested in both geometry and quantum computation. We show how to treat Grassmann manifolds which are very important examples of manifolds in mathematics and physics.
Kazuyuki Fujii
wiley +1 more source
Some relations between Hodge numbers and invariant complex structures on compact nilmanifolds
Let N be a simply connected real nilpotent Lie group, n its Lie algebra, and € a lattice in N. If a left-invariant complex structure on N is Γ-rational, then HƏ̄s,t(Γ/N) ≃ HƏ̄s,t(nC) for each s; t.
Yamada Takumi
doaj +1 more source
ON THE OFFSETS OF RULED SURFACES IN EUCLIDEAN SPACE
In the present paper, we study evolute offsets of a non-developable ruled surface in Euclidean 3-space E and classify the evolute offset with constant Gaussian curvature and constant mean curvature.
D. Yoon
semanticscholar +1 more source