Hi, I do quantum mechanics and a lot of time i work with expressions containing creation and annihilation operators. For example, I would like to expand a formula (a+A)^2, A is a-dagger. Normal answer would be a^2+2aA+A^2' but it's not correct since a and A are non-commuting (Lie Algebra). Moreover I wan to account for [a,A]=1, so that the end result is a^2+2aA+A^2+1.
Furthermore, I would like to convert an expression containing a and A to the one containing p and q (http://en.wikipedia.org/wiki/Creation_operators). there should be a substitution "{a:q+I*p,b:q-I*p}" and then simplification that accounts for commutations. I assume there should be a way to at least define a and A as commuting operators and may be there is a way to account for the commutation relation. Thank you --Kirill -- To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
