The Mermin-Wagner Theorem - Condensed Matter Theory Group
The Mermin-Wagner Theorem - Condensed Matter Theory Group
The Mermin-Wagner Theorem - Condensed Matter Theory Group
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How symmetry breaking occurs in principle<br />
Actors<br />
Proof of the <strong>Mermin</strong>-<strong>Wagner</strong> <strong>The</strong>orem<br />
Discussion<br />
<strong>The</strong> Bogoliubov inequality<br />
<strong>The</strong> <strong>Mermin</strong>-<strong>Wagner</strong> <strong>The</strong>orem<br />
To exploit the Schwarz inequality, we calculate the terms occurring<br />
in it:<br />
|(A, B)| 2 ≤ (A, A) (B, B)<br />
We now choose<br />
B =<br />
<br />
C † <br />
, H<br />
−<br />
Andreas Werner <strong>The</strong> <strong>Mermin</strong>-<strong>Wagner</strong> <strong>The</strong>orem