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-rw-r--r--aps_mm_2018.html33
-rw-r--r--figs/wolff_potts_field.webmbin1039359 -> 1020371 bytes
-rw-r--r--figs/wolff_potts_field_2.webmbin2562438 -> 0 bytes
-rw-r--r--time_compare.pngbin0 -> 18422 bytes
4 files changed, 25 insertions, 8 deletions
diff --git a/aps_mm_2018.html b/aps_mm_2018.html
index a3f6d91..3be9597 100644
--- a/aps_mm_2018.html
+++ b/aps_mm_2018.html
@@ -39,14 +39,14 @@ class: center, middle
Described by Hamiltonians whose degrees of freedom are spins `\(s\in X\)`
-$$\mathcal H=-\sum_{\langle ij\rangle}Z(s_i,s_j)-\sum_iH(s_i)$$
+$$\mathcal H=-\sum_{\langle ij\rangle}Z(s_i,s_j)-\sum_iB(s_i)$$
for \\(Z\\) invariant under the action of rotations \\(r\in R\\), or \\(Z(r\cdot s,r\cdot t)=Z(s,t)\\).
<table style="border-collapse: collapse; width: 100%; margin: auto;">
<thead style="border-bottom: 2px solid #000;">
<tr>
- <td class="first"></td><td><i>X</i><td><i>R</i></td><td>Group Action</td><td>\(Z(s,t)\)</td><td>\(H(s)\)</td>
+ <td class="first"></td><td><i>X</i><td><i>R</i></td><td>Group Action</td><td>\(Z(s,t)\)</td><td>\(B(s)\)</td>
</tr>
</thead>
<tbody>
@@ -54,13 +54,13 @@ for \\(Z\\) invariant under the action of rotations \\(r\in R\\), or \\(Z(r\cdot
<td class="first">Ising model</td><td>\(\{-1,1\}\)</td><td>ℤ/2ℤ</td><td>\(0\cdot s\mapsto s\)<br>\(1\cdot s\mapsto-s\)</td><td>\(s\times t\)</td><td>\(Hs\)</td>
</tr>
<tr>
- <td class="first">Order-\(n\) model</td><td>\(S^n\)</td><td>\(\mathop{\mathrm{O}}(n)\)</td><td>\(O\cdot s\mapsto Os\)</td><td>\(s^{\mathrm T}t\)</td><td>\(H\cdot s\)</td>
+ <td class="first">Order-\(n\) model</td><td>\(S^n\)</td><td>\(\mathop{\mathrm{O}}(n)\)</td><td>\(O\cdot s\mapsto Os\)</td><td>\(s^{\mathrm T}t\)</td><td>\(H^{\mathrm T}s\)</td>
</tr>
<tr>
- <td class="first">Potts model</td><td>ℤ/<i>q</i>ℤ</td><td>ℤ/<i>q</i>ℤ</td><td>\(m\cdot s\mapsto{(s+m)}\pmod q\)</td><td>\(\delta(s,t)\)</td><td>\(\sum_mH_m\delta(m,s)\)</td>
+ <td class="first">Potts model</td><td>{0,…,<i>q</i> – 1}</td><td><i>D<sub>q</sub></i></td><td>Rotation & reflection<br> of polygon vertices</td><td>\(\delta(s,t)\)</td><td>\(\sum_mH_m\delta(m,s)\)</td>
</tr>
<tr>
- <td class="first">Clock model</td><td>ℤ/<i>q</i>ℤ</td><td>ℤ/<i>q</i>ℤ</td><td>\(m\cdot s\mapsto{(s+m)}\pmod q\)</td><td>\(\cos(2\pi\frac{s-t}q)\)</td><td>\(\sum_mH_m\cos(2\pi\frac{s-m}q)\)</td>
+ <td class="first">Clock model</td><td>{0,…,<i>q</i> – 1}</td><td><i>D<sub>q</sub></i></td><td>Rotation & reflection<br> of polygon vertices</td><td>\(\cos(2\pi\frac{s-t}q)\)</td><td>\(\sum_mH_m\cos(2\pi\frac{s-m}q)\)</td>
</tr>
</tbody>
</table>
@@ -188,9 +188,9 @@ class: split-40
Consider the clock Potts model with field
`\[
H(m)=0.01\times\begin{cases}
-0 & \text{if $m=0$ (black)}\\
-\cos(2\pi/6) & \text{if $m=1$ (grey}\\
--\cos(2\pi/6) & \text{if $m=2$ (white)}
+0 & \text{if $m=0$ (blue)}\\
+\cos(2\pi/6) & \text{if $m=1$ (green}\\
+-\cos(2\pi/6) & \text{if $m=2$ (yellow)}
\end{cases}
\]`
@@ -204,6 +204,23 @@ No rotation `\(r\in\mathbb Z/3\mathbb Z\)` that takes field to the identity!
---
+class: split-40
+
+.column[
+
+# Correlation time comparison
+
+The correlation time of this algorithm beats metropolis and hybrid Wolff/metropolis in whole phase space!
+
+Pictured: 2D Ising (`\(128\times128\)`) correlation time as a function of field for three algorithms in high-temperature phase (top), at `\(T_c\)` (middle), and in the low temperature phase (bottom).
+]
+
+.column[
+<img src="time_compare.png" style="float: right; width: 32%" />
+]
+
+---
+
# Correlation time scaling
Correlation time scales consistently in the whole phase space!
diff --git a/figs/wolff_potts_field.webm b/figs/wolff_potts_field.webm
index b97c976..2d0d230 100644
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diff --git a/figs/wolff_potts_field_2.webm b/figs/wolff_potts_field_2.webm
deleted file mode 100644
index 2aa4c8d..0000000
--- a/figs/wolff_potts_field_2.webm
+++ /dev/null
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diff --git a/time_compare.png b/time_compare.png
new file mode 100644
index 0000000..035531a
--- /dev/null
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