Timeline for Are there any known criteria for quadratic mapping from R^n to R^n being surjective?
Current License: CC BY-SA 3.0
3 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 1, 2014 at 8:06 | comment | added | Name | @J.Martel Thank you for your comment. It does imply! If $q_1$ and $q_2$ are both regular, and at least one of them is definite then they are simultaneously diagonalizable (see Greub, Linear Algebra, 1967, Third edition, Ch. IX, p.256). | |
| Jan 24, 2014 at 15:01 | comment | added | JHM | I don't think your criterion is correct. In particular, $q_1, q_2$ regular and not simultaneously diagonalizable does not imply that either of $q_1, q_2$ are indefinite (which certainly is necessary!). | |
| Jan 13, 2014 at 17:07 | history | answered | Name | CC BY-SA 3.0 |