saving work

This commit is contained in:
Pierre-Francois Loos 2022-09-16 13:38:42 +02:00
parent 061430e7e1
commit 462c33c1b0

44
g.tex
View File

@ -456,7 +456,7 @@ The time-averaged contribution of the on-state weight can then be easily calcula
Details of the implementation of this effective dynamics can be in found in Refs.~\onlinecite{Assaraf_1999B} and \onlinecite{Caffarel_2000}. Details of the implementation of this effective dynamics can be in found in Refs.~\onlinecite{Assaraf_1999B} and \onlinecite{Caffarel_2000}.
%=======================================% %=======================================%
\subsection{General domains} \subsection{Multi-state domains}
\label{sec:general_domains} \label{sec:general_domains}
%=======================================% %=======================================%
@ -584,21 +584,25 @@ We then have
\qty[ \prod_{k=0}^{p-1} \mel{ I_k }{ \qty(T_{I_k})^{n_k-1} F_{I_k} }{ I_{k+1} } ] \qty[ \prod_{k=0}^{p-1} \mel{ I_k }{ \qty(T_{I_k})^{n_k-1} F_{I_k} }{ I_{k+1} } ]
G^{(n_p-1),{\cal D}}_{I_p I_N} G^{(n_p-1),{\cal D}}_{I_p I_N}
\end{multline} \end{multline}
where $\delta_{i,j}$ is a Kronecker delta.
This expression is the path-integral representation of the Green's matrix using only the variables $(\ket{I_k},n_k)$ of the effective dynamics defined over the set of domains. This expression is the path-integral representation of the Green's matrix using only the variables $(\ket{I_k},n_k)$ of the effective dynamics defined over the set of domains.
The standard formula derived above, Eq.~\eqref{eq:G} may be considered as the particular case where the domain associated with each state is empty, The standard formula derived above [see Eq.~\eqref{eq:G}] may be considered as the particular case where the domain associated with each state is empty,
In that case, $p=N$ and $n_k=1$ for $k=0$ to $N$ and we are left only with the $p$-th component of the sum, that is, $G^{(N)}_{I_0 I_N} In that case, $p=N$ and $n_k=1$ for $0 \le k \le N$ and we are left only with the $p$th component of the sum, that is, $G^{(N)}_{I_0 I_N}
= \prod_{k=0}^{N-1} \mel{ I_k }{ F_{I_k} }{ I_{k+1} } $ where $F=T$. = \prod_{k=0}^{N-1} \mel{ I_k }{ F_{I_k} }{ I_{k+1} } $ where $F=T$.
To express the fundamental equation for $G$ under the form of a probabilistic average, we write the importance-sampled version of the equation To express the fundamental equation for $G$ under the form of a probabilistic average, we write the importance-sampled version of the equation
\be \begin{multline}
\label{eq:Gbart} \label{eq:Gbart}
{\bar G}^{(N)}_{I_0 I_N}={\bar G}^{(N),{\cal D}}_{I_0 I_N} + \bar{G}^{(N)}_{I_0 I_N}=\bar{G}^{(N),\cD}_{I_0 I_N} +
\sum_{p=1}^{N} \sum_{p=1}^{N}
\sum_{|I_1\rangle \notin {\cal D}_{I_0}, \hdots , |I_p\rangle \notin {\cal D}_{I_{p-1}}} \sum_{\ket{I_1} \notin \cD_{I_0}, \ldots , \ket{I_p} \notin \cD_{I_{p-1}}}
\sum_{n_0 \ge 1} ... \sum_{n_p \ge 1} \sum_{n_0 \ge 1} \cdots \sum_{n_p \ge 1}
\delta(\sum_k n_k=N+1) \Big[ \prod_{k=0}^{p-1} [\frac{\PsiG_{I_{k+1}}}{\PsiG_{I_k}} \langle I_k| T^{n_k-1}_{I_k} F_{I_k} |I_{k+1} \rangle \Big] \\
{\bar G}^{(n_p-1),{\cal D}}_{I_p I_N}. \times
\ee \delta_{\sum_k n_k,N+1} \qty{ \prod_{k=0}^{p-1} \qty[ \frac{\PsiG_{I_{k+1}}}{\PsiG_{I_k}} \mel{ I_k }{ \qty(T_{I_k})^{n_k-1} F_{I_k} }{ I_{k+1} } ] }
\bar{G}^{(n_p-1),\cD}_{I_p I_N}.
\end{multline}
Introducing the weight Introducing the weight
\be \be
W_{I_k I_{k+1}} = \frac{\mel{ I_k }{ \qty(T_{I_k})^{n_k-1} F_{I_k} }{ I_{k+1} }}{\mel{ I_k }{ \qty(T^{+}_{I_k})^{n_k-1} F^+_{I_k} }{ I_{k+1} }} W_{I_k I_{k+1}} = \frac{\mel{ I_k }{ \qty(T_{I_k})^{n_k-1} F_{I_k} }{ I_{k+1} }}{\mel{ I_k }{ \qty(T^{+}_{I_k})^{n_k-1} F^+_{I_k} }{ I_{k+1} }}
@ -606,20 +610,22 @@ Introducing the weight
and using the effective transition probability defined in Eq.~\eqref{eq:eq3C}, we get and using the effective transition probability defined in Eq.~\eqref{eq:eq3C}, we get
\be \be
\label{eq:Gbart} \label{eq:Gbart}
\bar{G}^{(N)}_{I_0 I_N}=\bar{G}^{(N),\cD}_{I_0 I_N}+ \sum_{p=1}^{N} \bar{G}^{(N)}_{I_0 I_N} = \bar{G}^{(N),\cD}_{I_0 I_N} + \sum_{p=1}^{N}
\bigg \langle \expval{
\Big( \prod_{k=0}^{p-1} W_{I_k I_{k+1}} \Big) \qty( \prod_{k=0}^{p-1} W_{I_k I_{k+1}} )
{\bar G}^{(n_p-1), {\cal D}}_{I_p I_N} \bar{G}^{(n_p-1), {\cal D}}_{I_p I_N}
\bigg \rangle }
\ee \ee
where the average is defined as where the average is defined as
\be \begin{multline}
\expval{F} \expval{F}
= \sum_{|I_1\rangle \notin {\cal D}_{I_0}, \hdots , |I_p\rangle \notin {\cal D}_{I_{p-1}}} = \sum_{\ket{I_1} \notin \cD_{I_0}, \ldots , \ket{I_p} \notin \cD_{I_{p-1}}}
\sum_{n_0 \ge 1} \cdots \sum_{n_p \ge 1} \sum_{n_0 \ge 1} \cdots \sum_{n_p \ge 1}
\delta_{\sum_k n_k,N+1} \delta_{\sum_k n_k,N+1}
\prod_{k=0}^{N-1}\cP_{I_k \to I_{k+1}}(n_k-1) F(I_0,n_0;...;I_N,n_N) \\
\ee \times
\prod_{k=0}^{N-1}\cP_{I_k \to I_{k+1}}(n_k-1) F(I_0,n_0;\ldots.;I_N,n_N)
\end{multline}
In practice, a schematic DMC algorithm to compute the average is as follows.\\ In practice, a schematic DMC algorithm to compute the average is as follows.\\
i) Choose some initial vector $\ket{I_0}$\\ i) Choose some initial vector $\ket{I_0}$\\
ii) Generate a stochastic path by running over $k$ (starting at $k=0$) as follows.\\ ii) Generate a stochastic path by running over $k$ (starting at $k=0$) as follows.\\