From 66bd034adc5bbb782e06780b8f1625ec0a53332e Mon Sep 17 00:00:00 2001 From: Jaron Kent-Dobias Date: Fri, 7 Jan 2022 16:53:23 +0100 Subject: Started some notes about the 2-spin partition function. --- stokes.tex | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/stokes.tex b/stokes.tex index 91f7f18..70a7ed7 100644 --- a/stokes.tex +++ b/stokes.tex @@ -392,6 +392,20 @@ separatrix of a third. This means that when the imaginary energies of two critical points are brought to the same value, their surfaces of constant imaginary energy join. +\begin{equation} + \begin{aligned} + Z(\beta) + &=\int_{S^{N-1}}dx\,e^{-\beta H(x)} + =\int_{\mathbb R^N}dx\,\delta(x^2-N)e^{-\beta H(x)} \\ + &=\frac1{2\pi}\int_{\mathbb R^N}dx\,d\lambda\,e^{-\frac12\beta x^TJx-\lambda(x^Tx-N)} \\ + &=\frac1{2\pi}\int_{\mathbb R^N}dx\,d\lambda\,e^{-\frac12x^T(\beta J+\lambda I)x+\lambda N} \\ + &=\frac1{2\pi}\int d\lambda\,\sqrt{\frac{(2\pi)^N}{\det(\beta J+\lambda I)}}e^{\lambda N} \\ + &=\frac1{2\pi}\int d\lambda\,\sqrt{\frac{(2\pi)^N}{\prod_i(\beta\lambda_i+\lambda)}}e^{\lambda N} \\ + &=(2\pi)^{N/2-1}\int d\lambda\,e^{\lambda N-\frac12\sum_i\log(\beta\lambda_i+\lambda)} \\ + &\simeq(2\pi)^{N/2-1}\int d\lambda\,e^{\lambda N-\frac N2\int d\lambda'\,\rho(\lambda')\log(\beta\lambda'+\lambda)} \\ + \end{aligned} +\end{equation} + \subsection{Pure \textit{p}-spin} \begin{equation} -- cgit v1.2.3-54-g00ecf