I've never worked with REDUCE before - but now I want to use it for quantum mechanics. Therefore I want to use the package physop:
At first I wanted to try an example of the pdf on page 10. Unfortunately the program doesn't take care of the fact that the operators don't commutate. When I write "A*B;" I get the result "B*A":
What did I wrong?
I downloaded reduce from: https://sourceforge.net/projects/reduce-algebra/files/latest/download
Thank you very much for help,
Hm, It works here as shown in the physop documentation. What is the built date of your REDUCE? I remember that I fixed a problem in that code some time ago. Can you build from svn and try?
thank you very much for your answer!!
On http://sourceforge.net/projects/reduce-algebra/files/ I followed the link after "Looking for the latest version?" which was not the newest. Now I downloaded the newer one which works :-)
Just a short other question - is there a possibility to use something like the kronecker-delta? I want to express something like:
LET COMM(A(j), B(k)) = kroenecker(j,k);
Thank you very much,
Good to hear that the latest version works. Concerning the use of a Kronecker delta you could just define an
operator (as it is done in the physop test file) and use let rules to define its properties if needed.
thanks again for your answer.
Unfortunately I've a further problem:
I get a wrong result on the right hand. With the defined Anti-Commutators I expect -D(k,z)*C(k) for (this is a normal, not a anticommutator). Is this a bug in the program or did I something wrong?
Thank you very much again,
Could you please tell me why you think your indicated term should be zero? My hand calculation confirms
the result physop returns. Maybe we should continue this discussion via private e-mail.
this maybe the best way. My email-adress is ALueckegmx.net - Can you write me a mail - so that I have your adress and can tell you my way to calculate the commutator? Can I speak german with you?
For the case that someone has similar problems. Eberhard found my mistake:
Commands like "FOR ALL N,M LET ANTICOMM(C(N),C(M))=0" are ignored unless the command "NONCOM C, C" is used. The way I used the NONCOM-command before is not enough.