Skip to main content
2 of 2
removed deprecated tag 'analysis' (since question was bumped to the front page)
Ricardo Andrade
  • 6.2k
  • 5
  • 42
  • 69

Nearly elliptic equations

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} )