17,507 research outputs found
Determinants Associated to Zeta Matrices of Posets
We consider the matrix , where the entries of
are the values of the zeta function of the finite poset . We give a
combinatorial interpretation of the determinant of and establish
a recursive formula for this determinant in the case in which is a boolean
algebra.Comment: 14 pages, AMS-Te
How Ordinary Elimination Became Gaussian Elimination
Newton, in notes that he would rather not have seen published, described a
process for solving simultaneous equations that later authors applied
specifically to linear equations. This method that Euler did not recommend,
that Legendre called "ordinary," and that Gauss called "common" - is now named
after Gauss: "Gaussian" elimination. Gauss's name became associated with
elimination through the adoption, by professional computers, of a specialized
notation that Gauss devised for his own least squares calculations. The
notation allowed elimination to be viewed as a sequence of arithmetic
operations that were repeatedly optimized for hand computing and eventually
were described by matrices.Comment: 56 pages, 21 figures, 1 tabl
Electronic Fock spaces: Phase prefactors and hidden symmetry
Efficient technique of manipulation with phase prefactors in electronic Fock
spaces is developed. Its power is demonstrated on example of both relatively
simple classic configuration interaction matrix element evaluation and
essentially more complicated coupled cluster case. Interpretation of coupled
cluster theory in terms of a certain commutative algebra is given.Comment: LaTex, 31 pages, submitted to Int. J. Quantum Che
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