What you know you can't explain, but you feel it. You've felt it your entire life, that there's something wrong with the world. You don't know what it is, but it's there, like a splinter in your mind, driving you mad.
What you know you can't explain, but you feel it. You've felt it your entire life, that there's something wrong with the world. You don't know what it is, but it's there, like a splinter in your mind, driving you mad.
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Tools /
MpExpectationOldThis tool calculates the expectation value of an operator. Computational complexity: {$L m^3 d^2 M^2$} [*] Matrix Product Toolkit version HEAD-0.7.4.0 (subversion tree rev 838M) Compiled on Feb 8 2008 at 18:56:58 usage: mp-expectation [options] <psi1> <operator> [<psi2>] Allowed options: --help show this help message -r [ --r ] display only the real part of the result -i [ --i ] display only the imaginary part of the result --notempfile don't use a temporary data file, keep everything in RAM (faster, but needs enough RAM) -v [ --verbose ] extra debug output The operator is of the form Only operators that transform as a scalar can have their expectation value taken, which therefore implies that the wavefunctions By default, the result is shown in C++ complex number format "(real,imag)". The There is a variant of Examplesmp-expectation groundstate lattice:H mp-expectation psi1 "lattice:N(2)" psi2 As usual, we use quotes (" or ') to stop the shell from interpreting the brackets. See also[*] in principle, the {$d^2M^2$} can be reduced to {$dM$}, with a re-summing of loop indices. But for typical operators this won't do much, the {$d^2M^2$} is the number of non-zero matrix elements, and in practice operators are usually quite sparse. |