Dear Elham Shabani, In general this is a difficult problem. For two given Lie algebras one can use GAP to find a number of invariants (the centre, derived subalgebra, Levi decomposition,....). If one of these is not equal for your Lie algebras, then you have proved that they are not isomorphic. However, if they are isomorphic, then the only general way of proving that (I know of) is to write down the polynomial equations that come from the isomorphism condition, and then perform Groebner basis calculations. In theory this works fine if the ground field is algebraically closed. For other fields it is more difficult. If you say what your Lie algebras are, then I might be able to provide more help.
Best wishes, Willem de Graaf On 19 December 2017 at 09:22, elham shabani <e.shabani.1...@gmail.com> wrote: > > _______________________________________________ > Forum mailing list > Forum@gap-system.org > https://mail.gap-system.org/mailman/listinfo/forum > _______________________________________________ Forum mailing list Forum@gap-system.org https://mail.gap-system.org/mailman/listinfo/forum
