Maybe this is a silly question (or not even a question), but I was wondering whether the cotangent bundle of a submanifold is somehow canonically related to the cotangent bundle of the ambient space.
To be more precise:
Let NN be a manifold and iota:MhookrightarrowNiota:MhookrightarrowN be an embedded (immersed) submanifold. Is the cotangent bundle TastMTastM somehow canonical related to the cotangent bundle TastNTastN. Canonical means, without choosing a metric on NN. The choice of a metric gives an isomorphism of TNTN and TastNTastN and therefore a "relation", since the tangent bundle of the submanifold MM can be viewed in a natural way as a subspace of the tangent bundle of the ambient space NN (iotaiota induces an injective linear map at each point iotaast:TpMrightarrowTpNiotaast:TpMrightarrowTpN). I think this is not true for the cotangent space (without a metric)
Moreover, the cotangent bundle TastNTastN of a manifold NN is a kind of "prototype" of a symplectic manifold. The symplectic structure on TastNTastN is given by omegaTastN=−dlambdaomegaTastN=−dlambda, where lambdalambda is the Liouville form on the cotangent bundle. (tautological one-form, canonical one-form, symplectic potential or however you want). The cotangent bundle of the submanifold TastMTastM inherits in the same way a canonical symplectic structure. So, is there a relation between TastNTastN and TastMTastM respecting the canonical symplectic structures. (I think the isomorphism given by a metric is respecting (relating) these structures, or am I wrong?) As I said, this question is perhaps strange, but the canonical existence of the symplectic structure on the cotangent bundle is "quite strong". For example:
A given diffeomorphism f:XrightarrowYf:XrightarrowY induces a canonical symplectomorphism Tastf:TastYrightarrowTastXTastf:TastYrightarrowTastX (this can be proved by the special "pullback cancellation" property of the Liouville form).
So in the case of a diffeomorphism the symplectic structures are "the same".
Ok, a diffeomorphism has more structure than an embedding, but perhaps there is a similar relation between TastMTastM and TastNTastN?
EDIT: Sorry fot the confusion, but Kevins post is exactly a reformulation of the problem, I'm interested in. To clarify things: with the notation of Kevin's post:
When (or whether) are the pulled back symplectic structures the same ? Under what circumstances holds aastomegaTastN=bastomegaTastNaastomegaTastN=bastomegaTastN
I think this isn't true for any submanifold MsubsetNMsubsetN, but what is a nice counterexample? Is it true for more restricted submanifolds as for example embedded submanifolds which are not just homoeomorphisms onto its image, but diffeomorphisms (perhaps here the answer is yes, using the diffeomorphism remark above?)?
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