On natural vector bundle morphisms over
A. Ntyam, A. Mba (2009)
Annales Polonici Mathematici
Similarity:
Some properties and applications of natural vector bundle morphisms over are presented.
A. Ntyam, A. Mba (2009)
Annales Polonici Mathematici
Similarity:
Some properties and applications of natural vector bundle morphisms over are presented.
J. Kurek, W. M. Mikulski (2007)
Annales Polonici Mathematici
Similarity:
We classify all -natural operators transforming second order connections Γ: Y → J²Y on a fibred manifold Y → M into second order connections on the vertical Weil bundle corresponding to a Weil algebra A.
Jan Kurek, Włodzimierz M. Mikulski (2011)
Annales Polonici Mathematici
Similarity:
We extend the concept of r-order connections on fibred manifolds to the one of (r,s,q)-order projectable connections on fibred-fibred manifolds, where r,s,q are arbitrary non-negative integers with s ≥ r ≤ q. Similarly to the fibred manifold case, given a bundle functor F of order r on (m₁,m₂,n₁,n₂)-dimensional fibred-fibred manifolds Y → M, we construct a general connection ℱ(Γ,Λ):FY → J¹FY on FY → M from a projectable general (i.e. (1,1,1)-order) connection on Y → M by means of an...
Włodzimierz M. Mikulski (2002)
Colloquium Mathematicae
Similarity:
Let be the r-jet prolongation of the cotangent bundle of an n-dimensional manifold M and let be the dual vector bundle. For natural numbers r and n, a complete classification of all linear natural operators lifting 1-forms from M to 1-forms on is given.
Zdeněk Dušek (2015)
Czechoslovak Mathematical Journal
Similarity:
Let be a 4-dimensional Einstein Riemannian manifold. At each point of , the tangent space admits a so-called Singer-Thorpe basis (ST basis) with respect to the curvature tensor at . In this basis, up to standard symmetries and antisymmetries, just components of the curvature tensor are nonzero. For the space of constant curvature, the group acts as a transformation group between ST bases at and for the so-called 2-stein curvature tensors, the group acts as a transformation...
Gurupadavva Ingalahalli, C.S. Bagewadi (2018)
Communications in Mathematics
Similarity:
In this paper we study -recurrence -curvature tensor in-contact metric manifolds.
Włodzimierz M. Mikulski (2003)
Annales Polonici Mathematici
Similarity:
All natural operators A transforming a linear vector field X on a vector bundle E into a vector field A(X) on the r-jet prolongation of E are given. Similar results are deduced for the r-jet prolongations and in place of .
Jan Kurek, Włodzimierz M. Mikulski (2012)
Annales Polonici Mathematici
Similarity:
We prove that the problem of finding all -natural operators lifting classical linear connections ∇ on m-manifolds M to classical linear connections on the Weil bundle corresponding to a p-dimensional (over ℝ) Weil algebra A is equivalent to the one of finding all -natural operators transforming classical linear connections ∇ on m-manifolds M into base-preserving fibred maps .
Jacek Dębecki (2016)
Czechoslovak Mathematical Journal
Similarity:
We give a classification of all linear natural operators transforming -vectors (i.e., skew-symmetric tensor fields of type ) on -dimensional manifolds to tensor fields of type on , where is a Weil bundle, under the condition that , and . The main result of the paper states that, roughly speaking, each linear natural operator lifting -vectors to tensor fields of type on is a sum of operators obtained by permuting the indices of the tensor products of linear natural...
Jan Kurek, Włodzimierz Mikulski (2016)
Annales Universitatis Mariae Curie-Sklodowska, sectio A – Mathematica
Similarity:
We study how a projectable general connection in a 2-fibred manifold and a general vertical connection in induce a general connection in .
W. M. Mikulski (2009)
Annales Polonici Mathematici
Similarity:
We describe all -gauge-natural operators lifting right-invariant vector fields X on principal G-bundles P → M with m-dimensional bases into vector fields (X) on the rth order principal prolongation of P → M. In other words, we classify all -natural transformations covering the identity of , where is the r-jet prolongation of the Lie algebroid LP=TP/G of P, i.e. we find all -natural transformations which are similar to the Kumpera-Spencer isomorphism . We formulate axioms which...
J. Kurek, W. M. Mikulski (2010)
Annales Polonici Mathematici
Similarity:
Let m and r be natural numbers and let be the rth order frame bundle functor. Let and be natural bundles, where . We describe all -natural operators A transforming sections σ of and classical linear connections ∇ on M into sections A(σ,∇) of . We apply this general classification result to many important natural bundles F and G and obtain many particular classifications.
Włodzimierz M. Mikulski (2010)
Annales Polonici Mathematici
Similarity:
Let Y → M be a fibred manifold with m-dimensional base and n-dimensional fibres. Let r, m,n be positive integers. We present a construction of rth order holonomic connections on Y → M from general connections Γ:Y → J¹Y on Y → M by means of torsion free classical linear connections ∇ on M. Then we prove that any construction B of rth order holonomic connections on Y → M from general connections Γ:Y → J¹Y on Y → M by means of torsion free classical linear connections ∇ on M is equal...
Josef Mikeš, Karl Strambach (2015)
Czechoslovak Mathematical Journal
Similarity:
We determine in the form of curves corresponding to strictly monotone functions as well as the components of affine connections for which any image of under a compact-free group of affinities containing the translation group is a geodesic with respect to . Special attention is paid to the case that contains many dilatations or that is a curve in . If is a curve in and is the translation group then we calculate not only the components of the curvature and the Weyl...
Miroslav Doupovec, Ivan Kolář (2019)
Archivum Mathematicum
Similarity:
It is well known that the concept of holonomic -jet can be geometrically characterized in terms of the contact of individual curves. However, this is not true for the semiholonomic -jets, [5], [8]. In the present paper, we discuss systematically the semiholonomic case.
Oihane F. Blanco, Miguel Sánchez, José M. Senovilla (2013)
Journal of the European Mathematical Society
Similarity:
, that is to say, Lorentzian manifolds with vanishing second derivative of the curvature tensor , are characterized by several geometric properties, and explicitly presented. Locally, they are a product where each factor is uniquely determined as follows: is a Riemannian symmetric space and is either a constant-curvature Lorentzian space or a definite type of plane wave generalizing the Cahen–Wallach family. In the proper case (i.e., at some point), the curvature...
Anna Bednarska (2013)
Annales Universitatis Mariae Curie-Sklodowska, sectio A – Mathematica
Similarity:
We describe all -natural operators transforming projectable-projectable classical torsion-free linear connections on fibred-fibred manifolds into classical linear connections on cotangent bundles of . We show that this problem can be reduced to finding -natural operators for , and , .
Anna Bednarska (2012)
Annales Universitatis Mariae Curie-Sklodowska, sectio A – Mathematica
Similarity:
We prove that any first order -natural operator transforming projectable general connections on an -dimensional fibred-fibred manifold into general connections on the vertical prolongation of is the restriction of the (rather well-known) vertical prolongation operator lifting general connections on a fibred manifold into (the vertical prolongation of ) on .
Ernst Kuwert, Tobias Lamm, Yuxiang Li (2015)
Journal of the European Mathematical Society
Similarity:
For two-dimensional, immersed closed surfaces , we study the curvature functionals and with integrands and , respectively. Here is the second fundamental form, is the mean curvature and we assume . Our main result asserts that critical points are smooth in both cases. We also prove a compactness theorem for -bounded sequences. In the case of this is just Langer’s theorem [16], while for we have to impose a bound for the Willmore energy strictly below as an additional...
Jan Kurek, Włodzimierz Mikulski (2014)
Annales Universitatis Mariae Curie-Sklodowska, sectio A – Mathematica
Similarity:
If is a Riemannian manifold, we have the well-known base preserving vector bundle isomorphism given by between the tangent and the cotangent bundles of . In the present note, we generalize this isomorphism to the one between the -th order vector tangent and the -th order cotangent bundles of . Next, we describe all base preserving vector bundle maps depending on a Riemannian metric in terms of natural (in ) tensor fields on .
Anna Bednarska (2011)
Annales Universitatis Mariae Curie-Sklodowska, sectio A – Mathematica
Similarity:
We classify all -natural operators transforming projectable-projectable torsion-free classical linear connections on fibered-fibered manifolds of dimension into th order Lagrangians on the fibered-fibered linear frame bundle on . Moreover, we classify all -natural operators transforming projectable-projectable torsion-free classical linear connections r on fiberedfibered manifolds of dimension into Euler morphism on . These classifications can be expanded on...
Frédéric Campana, Thomas Peternell (2011)
Bulletin de la Société Mathématique de France
Similarity:
We first prove a strengthening of Miyaoka’s generic semi-positivity theorem: the quotients of the tensor powers of the cotangent bundle of a non-uniruled complex projective manifold have a pseudo-effective (instead of generically nef) determinant. A first consequence is that is of general type if its cotangent bundle contains a subsheaf with ‘big’ determinant. Among other applications, we deduce that if the universal cover of is not covered by compact positive-dimensional analytic...