Timeline for Does MAGMA have a function to decide if two indefinite, integral quadratic forms are isometric?
Current License: CC BY-SA 2.5
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| Nov 27, 2009 at 7:17 | comment | added | moonface | OK, if you really want to use MAGMA, you can use some trick like trying to replace M,N by p-adically close but definite forms M', N'; then use Magma's implemented functions to check if these are equivalent at p. (You do this at all primes p dividing the discriminant.) I'm not sure if Magma's implemented functions cover the "spinor" version of this, however. | |
| Nov 27, 2009 at 4:42 | comment | added | Guillermo Mantilla | Yes by strong approximation the spinor genus and the isometry class are the same for indefinite forms( at least in dimension bigger than 2). The problem is that I don't know how to check whether the spinor genus of M and N is the same. If M is indefinite MAGMA does not accept LatticeWithGram(M). | |
| Nov 26, 2009 at 18:48 | history | answered | moonface | CC BY-SA 2.5 |