Classifies Killing forms of arbitrary degree on specific nilpotent Lie groups.
problem Classifying Killing forms of arbitrary degree on specific Lie groups.
method Analyzing left-invariant Killing forms on simply connected 2-step nilpotent Lie groups with left-invariant metrics.
result Classified Killing forms when center is at most 2-dimensional.
Left-invariant forms solve Dolbeault cohomology for complex nilmanifolds.
problem Computing Dolbeault cohomology for complex nilmanifolds.
method Inducing isomorphisms in cohomology using left-invariant forms.
result Invariant forms compute Dolbeault cohomology in every bidegree.
The paper studies Riemannian metrics on tangent Lie groups using two left-invariant metrics.
problem Exploring Riemannian structures on tangent Lie groups.
method Defining a new left-invariant Riemannian metric on the tangent Lie group using two left-invariant metrics and symplectic forms.
result Explicit formulas for the Levi-Civita connection, tensor curvature, and sectional curvature of the new metric in terms of the original metrics.
New method simplifies cohomology computation for specific Lie group structures.
problem Computing cohomology for hypocomplex structures on compact Lie groups.
method Dual of Fréchet-Schwartz spaces theory applied to hypocomplex structures.
result Top-degree cohomology can be computed using only left-invariant forms.
Study finds only complex 2-step nilpotent Lie groups have Killing-Yano forms.
problem Characterizing Lie groups with Killing-Yano forms.
method Analyzing 2-step nilpotent Lie groups and connected graphs.
result Only complex 2-step nilpotent Lie groups have non-degenerate Killing-Yano forms.
New method classifies symplectic structures on Lie groups.
problem Classifying left-invariant symplectic structures on Lie groups.
method Using moduli space of left-invariant nondegenerate 2-forms.
result Classified left-invariant symplectic structures on specific Lie groups.
We study left invariant contact forms and left invariant symplectic forms on Lie groups. We give the classification of all symplectic structures on nilpotent Lie algebras up the dimension 6.
Computational techniques calculate dimensions of complex structures.
problem Calculating dimensions of complex structures on manifolds.
method Developed computational techniques to calculate Kodaira dimension and Dolbeault harmonic forms.
result Computed dimensions of left-invariant almost complex structures.
Study finds optimal loops in hyperbolic space with Finsler structure.
problem Optimal loops in Finsler hyperbolic plane.
method Left-invariant Finsler structure, convex trigonometry functions.
result Optimal isoperimetric loops found in terms of trigonometry functions.
Survey on invariant conformal Killing forms on Lie groups.
problem Understanding invariant conformal Killing forms on Lie groups.
method Review of recent results and mention of open questions.
result Discussion of recent findings and open research areas.
A n-dimensional Lie group G equipped with a left invariant symplectic form $\om^+$ is called a symplectic Lie group. It is well-known that $\om^+$ induces a left invariant affine structure on G. Relatively to this affine structure we show that the left invariant Poisson tensor π+ corresponding to $\om^+$ is po…
Study Dolbeault harmonic forms on Lie group quotients with specific structures.
problem Characterize the space of Dolbeault harmonic (1,1)-forms on compact Lie group quotients.
method Analyze left invariant almost Hermitian structures on 4D Lie groups and their quotients.
result Dimension of Dolbeault harmonic (1,1)-forms depends on existence of a specific anti-self-dual form.
Study Killing forms on 2-step nilpotent Lie groups, finding their structure and dimensions.
problem Characterize Killing forms on 2-step nilpotent Lie groups with a Riemannian metric.
method Analyze left-invariant Killing k-forms on simply connected 2-step nilpotent Lie groups, decomposing into irreducible factors.
result The space of Killing k-forms is at most one-dimensional for k=2 or k=3.
We consider nilmanifolds with left-invariant complex structure and prove that small deformations of such structures are again left invariant if the Dolbeault-cohomology of the nilmanifold can be calculated using left-invariant forms. By a result of Console and Fino this is generically the case. Our main tool is an anal…
Study conformal Killing forms on specific nilpotent Lie groups.
problem Characterize conformal Killing forms on 2-step nilpotent Lie groups.
method Analyzing left-invariant forms on simply connected groups, proving properties of forms based on center dimension.
result Only specific forms exist under certain conditions.
We are interested in the class, in the Elie Cartan sense, of left invariant forms on a Lie group. We construct the class of Lie algebras provided with a contact form and classify the frobeniusian Lie algebras up to a contraction. We also study forms which are invariant by a subgroup. We show that the simple group SL(2n…
We study the geometry of a family of Lie groups, which contained the classical affine Lie groups, endowed with an exact left invariant symplectic form. We show that this family is closed by symplectic reduction and symplectic double extension in the sense of Dardié and Medina. We prouve also that these groups are endow…
In this paper, we investigate left-invariant geodesic orbit metrics on connected simple Lie groups, where the metrics are formed by the structures of generalized flag manifolds. We prove that all these left-invariant geodesic orbit metrics on simple Lie groups are naturally reductive.
Study odd generalized Einstein metrics on 3D Lie groups.
problem Classify odd generalized Einstein metrics on 3D Lie groups.
method Left-invariant generalized connections, divergence operators, and Ricci tensors.
result Describe all odd generalized Einstein metrics on all 3D Lie groups.
This work reviews left-invariant optimal control problems on Lie groups.
problem Optimal control problems on Lie groups with big symmetry.
method Review of main notions, methods, and results.
result Description of extremal trajectories and their optimality, cut time and cut locus, optimal synthesis.
In this work we deal with left invariant complex and symplectic structures on simply connected four dimensional solvable real Lie groups. We search the general form of such structures, when they exist and we make use of this information to determine all left invariant Kaehler structures. Finally, as an appendix we comp…
The paper studies conjugate points on Lie groups with specific metrics.
problem Existence and properties of conjugate points on Lie groups with left-invariant metrics.
method Using reformulated index form in terms of adjoint action, the paper proves sufficient conditions for conjugate points and provides bounds and criteria.
result All geodesics in compact semisimple Lie groups have conjugate points, with upper and lower bounds on conjugate times.
Study invariant CKY 2-forms on 5D Lie groups, classifying and determining their properties.
problem Classifying and understanding CKY 2-forms on 5D Lie groups.
method Classification and analysis of 5D metric Lie algebras with CKY tensors.
result First examples of CKY 2-forms on metric Lie algebras without Sasakian structures.
A special symplectic Lie group is a triple (G,ω,∇) such that G is a finite-dimensional real Lie group and ω is a left invariant symplectic form on G which is parallel with respect to a left invariant affine structure ∇. In this paper starting from a special symplectic Lie group we show how to ``defo…
The paper constructs a family of SKT metrics on the exceptional Lie group G2.
problem Constructing SKT metrics on the exceptional Lie group G2.
method Left-invariant integrable almost complex structure and construction of 7-parameter family of metrics.
result A 3-parameter family of left-invariant SKT metrics on G2.
Study on vector fields on Lie groups reveals surprising algebraic coincidences.
problem Characterizing vector fields on Lie groups with Riemannian metrics.
method Algebraic and geometric analysis of left-invariant vector fields on nilpotent Lie groups.
result Spaces of Killing, one-harmonic, and conformal vector fields coincide with the center of the Lie algebra on nilpotent Lie groups.
The paper finds a contact form on SL(2p) for p > 1.
problem Left invariant Pfaffian forms on SL(2p) are not contact forms for p > 1.
method Constructed a contact form invariant under SO(2p).
result Found a contact form on SL(2p) for p > 1.
Classifies nilpotent Lie groups with specific G2-structures.
problem Identifying 7D nilpotent Lie groups with purely coclosed G2-structures. method Examined all 7D nilpotent Lie algebras, classified them, and verified the existence or non-existence of G2-structures. result Provided a complete classification of 7D nilpotent Lie groups with purely coclosed G2-structures. Study of Hermitian and Gauduchon connections on Lie groups with almost Hermitian structures.
problem Characterizing connections on Lie groups with almost Hermitian structures.
method Analyzing left-invariant Hermitian and Gauduchon connections on Lie groups equipped with almost Hermitian structures.
result Explicit formulas for torsion components and curvature of Gauduchon connections on Lie groups.
Revisited study of real Jacobi group with invariant metrics and forms.
problem Characterizing the real Jacobi group and its invariant structures.
method Matrix realization, S-coordinates, left-invariant forms and metrics.
result Invariant metrics and forms on the Jacobi group and its quotients.
The study lists low-dimensional stratified groups and their properties.
problem Understanding the algebraic structure of stratified groups.
method Explicitly provided a list of low-dimensional stratified groups and their properties.
result All stratified groups in dimensions up to 7 and some free-nilpotent groups in dimensions up to 14 were studied.
Proves cohomology of elliptic structures on Lie groups can be algebraic.
problem Computing cohomology of elliptic structures on compact semisimple Lie groups.
method Used spectral sequences to construct an isomorphism between left-invariant and usual differential complexes.
result Reduced analytical problem to algebraic computation.
Study of complex and Hermitian structures on specific Lie groups.
problem Classifying Lie groups with specific geometric structures.
method Analysis of left-invariant structures on almost abelian Lie groups.
result Classification of six-dimensional generalized Kähler almost abelian Lie groups.
We provide a classification of ts-invariant sub-Lorentzian structures on 3 dimensional contact Lie groups. Our approach is based on invariants arising form the construction of a normal Cartan connection.
Flat Hermitian Lie algebras are always Kähler.
problem Classifying Lie groups with Hermitian structures that are flat.
method Analysis on the Hermitian geometry of 2-step solvable Lie groups.
result Flat Hermitian Lie algebras are Kähler.
Two specific Einstein metrics found on a product of SL(2,R) groups.
problem Classifying left-invariant Einstein metrics on a specific group product.
method Analyzing bi-invariant metrics under a one-parameter subgroup.
result Found two specific Einstein metrics: the Killing form and a nearly pseudo-Kähler metric.
For a connected Lie group G, we show that a complex structure on the total space TG of the tangent bundle of G that is left invariant and has the property that each left translation G-orbit is a totally real submanifold is induced from a smooth immersion of TG into the complexification of G. For G compact and connected…
The main aim of this paper is the description of a large class of lattices in some nilpotent Lie groups, sometimes filiformes, carrying a flat left invariant linear connection anf often a left invariant symplectic form. As a consequence we obtain an infinity of, non homeomorphic, compact affine or symplectic manifolds.…
Study para-complex structures on specific Lie groups, finding explicit forms and properties.
problem Characterizing para-Kähler structures on six-dimensional nilpotent Lie groups.
method Examined left-invariant para-complex structures on six-dimensional nilpotent Lie groups, obtained explicit expressions and investigated curvature properties.
result Para-complex structures are nilpotent and para-Kähler metrics are Ricci-flat.
Constructs special Kähler structures on Lie groups.
problem Creating special Kähler structures on Lie groups.
method Introducing twisted cartesian product and double extension process.
result Characterizes left invariant flat special Kähler structures.
The set E of Levi-Civita connections of left-invariant pseudo-Riemannian Einstein metrics on a given semisimple Lie group always includes D, the Levi-Civita connection of the Killing form. For the groups SU(l,j) (or SL(n,R), or SL(n,C) or, if n is even, SL(n/2,IH)), with 0<=j<=l and j+l>2 (or, n>2), we explicitly descr…
The study proves stability of a flow on specific Lie groups.
problem Global stability of the Pluriclosed flow on compact Lie groups.
method Computation of cohomology, verification of flat metrics, and analysis of complex structures.
result Stability of the pluriclosed flow on compact Lie groups of rank two.
We study n dimensional Riemanniann manifolds with harmonic forms of constant length and first Betti number equal to n−1 showing that they are 2-steps nilmanifolds with some special metrics. We also characterise, in terms of properties on the product of harmonic forms, the left invariant metrics among them. This all…
Study proves all left-invariant contact structures on 3D Lie groups are tight.
problem Characterizing tightness of left-invariant contact structures on 3D Lie groups.
method Riemannian methods and unique factorization property for Lie groups.
result All left-invariant contact structures on 3D Lie groups are tight.
This paper studies moduli spaces of statistical structures on Lie groups.
problem Understanding statistical structures on Lie groups.
method Introduced and studied moduli spaces for left-invariant statistical structures on Lie groups.
result Moduli spaces of left-invariant Riemannian metrics are singletons for certain Lie groups.
Study on harmonic spinors on specific Lie groups.
problem Existence of left-invariant harmonic spinors on 3D Lie groups.
method Revised spin Dirac operator formula for left-invariant spinors, identified constraints on Lie algebras, and classified metrics with harmonic spinors.
result Identified conditions and metrics for left-invariant harmonic spinors on 3D Lie groups.
In this note we prove that any left-invariant almost Hermitian structure on a 2-step nilmanifold is Ricci-flat with respect to the Chern connection and that it is Ricci-flat with respect to another canonical connection if and only if it is cosymplectic.
Study on completeness of metrics on specific Lie groups.
problem Completeness of left-invariant Lorentzian metrics on 3D non-unimodular Lie groups.
method Analyzing metrics with Lie algebra of the form R⋉AR2 for various A. result Determine all geodesically complete and incomplete metrics for different cases of A.