Left- and Right- Kernels of Bilinear maps B:VxV->K for V.Spaces

  • Level: Graduate 
  • Thread starter Thread starter Bacle
  • Start date Start date
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
1 reply · 5K views
Bacle
Messages
656
Reaction score
1
Hi, all:

Let V be a vector space over k, and let B be a bilinear map into k,
i.e.:

B:VxV-->k

Define the left-kernel of B to be the set of A in V with

B (A,v)=0 for all v in V,

and define the right-kernel similarly.

Question: what relation is there between the two kernels , as subspaces
of V?

I am pretty sure the answer has to see with the tensor product V(x)V;

but I am not sure of how to express the dual of VxV in terms of the tensor

product. Any ideas?

Thanks.
 
Physics news on Phys.org
Unfortunately, the quote function is not working well, so I will
improvise. Let n be the dimension of V, so that Dim(VxV)=2n
and Dim(V(x)V)=n^2

I know that the element B' in V(x)V , corresponding to the
bilinear map B : VxV-->k , is a linear functional in V(x)V, and so
the kernel of B' has codimension 1, or, equivalently, dimension
n^2-1 in B(x)B.

But I don't know any properties of kernels of bilinear maps, and
I don't know if there is a way of somehow pulling back the kernel
of B' back into the kernel of B in VxV.

Anyway, I'll keep trying. Any Advice Appreciated.