# Differences

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grand_canonical_expectation_value [2013/10/13 16:22] nikolaj |
grand_canonical_expectation_value [2014/03/21 11:11] |
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- | ===== Grand canonical expectation value === | ||

- | ==== Definition ==== | ||

- | | @#88DDEE: $ w $ ... grand canonical weight | | ||

- | | @#FFBB00: $\langle A\rangle:=\sum_{N=0}^\infty w_N\cdot \langle A_N\rangle_N$ | | ||

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- | The functional $\langle \cdot\rangle_N$ denotes the expectation in the canonical ensamble of particle number $N$. So the grand canonical expectation value $\langle \cdot\rangle$ takes sequences of observables to a real. | ||

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- | ==== Discussion ==== | ||

- | We adopt the names of observables in canonical ensamble for the grand canonical ensamble. For example, if the internal energy in the canonical ensamble is defined as $U=\langle H\rangle$, then the grand canonical expectation value of the energy is denoted by $U$ as well and if formed from the sequence of all the $N$-particle Hamiltonians $H_N$. | ||

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- | We also extend function of classical canonical observables to such sequences. I.e. if $A$ has $A_N$, then $f(A)$ has entries $f(A_N)$. | ||

- | ==== Parents ==== | ||

- | === Requirements === | ||

- | [[Grand canonical weight]] |