Simplifying many body operator expressions

[Hypersphere]

Hello all,

Is there any really good software, package or otherwise, that is helpful for simplifying long operator expressions, particularly with (anti-commuting) electron operators? For example, I'd like to be able to transform Hamiltonians, project onto subspaces with specific occupation numbers and so on, without a lot of manual labor.

Currently I use the Quantum Notation package for Mathematica. It mostly works, but it doesn't understand that the square of an electron creation operator is zero, so there is still an element of discarding by inspection and the associated possibility of human error. I recently tried out the sneg package for Mathematica as well, but not all of the tutorial's examples seem to run properly in the current version of Mathematica. Hence I'm looking for something more complete.

Thanks in advance

 

[Valkarie]

for any advice!</code>I'd recommend looking into the GRAPE software for Matlab. It's a very comprehensive tool designed to simplify and manipulate operator expressions. It comes with a number of built-in functions that can be used to transform Hamiltonians, perform calculations on subspaces with specific occupation numbers, and more. GRAPE is also able to understand that the square of an electron creation operator is zero, so you don't have to do any manual discarding.