In mathematics, a double vector bundle is the combination of two compatible vector bundle structures, which contains in particular the tangent
{\displaystyle TE}
of a vector bundle
{\displaystyle E}
and the double tangent bundle
2
{\displaystyle T^{2}M}
.
A double vector bundle consists of
(
,
,
,
)
, where A double vector bundle morphism
(
consists of maps
is a bundle morphism from
is a bundle morphism from
is a bundle morphism from
is a bundle morphism from
The 'flip of the double vector bundle
is the double vector bundle
is a vector bundle over a differentiable manifold
{\displaystyle (TE,E,TM,M)}
is a double vector bundle when considering its secondary vector bundle structure.
is a differentiable manifold, then its double tangent bundle
{\displaystyle (TTM,TM,TM,M)}
is a double vector bundle.
Mackenzie, K. (1992), "Double Lie algebroids and second-order geometry, I", Advances in Mathematics, 94 (2): 180–239, doi:10.1016/0001-8708(92)90036-k