If you have a second order elliptic equation but the coefficients of the second order terms only form a nonnegative (instead of positive definite) matrix, then, do you know if there is any literature about this? (For example, the matrix of the second order terms can be diag{1,1,0,0} )
$\begingroup$
$\endgroup$
1
-
$\begingroup$ do you mean positive semi-definite $\endgroup$– tergiCommented Jul 11, 2012 at 16:05
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
They are called degenerate elliptic equations.
answered Jul 11, 2012 at 16:28