N_total is not a quantum number, but N is the quantum number. Have you tried specifying CONSERVED_QUANTUMNUMBERS="N"?
On Mar 27, 2013, at 10:06 AM, Jakub Zakrzewski jakub.zakrzewski@gmail.com wrote:
Hello everybody,
Let us take such a simple input file with irrelevant name parbh:
LATTICE="open chain lattice" MODEL="boson Hubbard" L=8 Nmax=4 N_total=8 NONLOCAL=0 U = 1.0 t = 0.24 CONSERVED_QUANTUMNUMBERS="N_total" SWEEPS=8 NUMBER_EIGENVALUES=1 {MAXSTATES=100}
I produce parbh.in.xml and then I run sparsediag getting a proper ground state energy (checked independently outside alps)
-1.457060131536948
I use DMRG on the same input file obtaining LOWER eigenenergy...
-1.6132399980266807
the result is little dependent on SWEEPS. MAXSTATES (which are rather large) and is obviously incorrect.
I must be doing something wrong but what is it? Help welcome
Thanks in advance, kuba
-- Jakub Zakrzewski Zakład Optyki Atomowej Instytut Fizyki im. M. Smoluchowskiego ul. Reymonta 4, 30-059 Kraków, Poland +48-12-6635555, fax +48126338494 http://chaos.if.uj.edu.pl/~kuba