ncg

bachelorthesis in physics
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commit 24757a9157b3ea60fb7ab6f74fbf227ef760e23d
parent 8b6913bddf52c3523aad41aab2419135c3b3b448
Author: miksa <milutin@popovic.xyz>
Date:   Wed,  9 Jun 2021 13:20:10 +0200

initial week10

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Asrc/week10.pdf | 0
Msrc/week10.tex | 70+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
2 files changed, 67 insertions(+), 3 deletions(-)

diff --git a/src/week10.pdf b/src/week10.pdf Binary files differ. diff --git a/src/week10.tex b/src/week10.tex @@ -135,9 +135,73 @@ Glaser} \end{align} \end{proposition} \begin{proof} - Will maybe be filled in if I go through the last two chapters in the - book and understand the proof. - \textbf{PROOF IN week10.pdf} + The dimension of our manifold $M$ is $\dim(M) = \text{Tr}(id) =4 $. Let us + take a $x \in M$, we have an asymtotic expansion of + $\text{Tr}(f(\frac{D_\omega}{\Lambda}))$ as $\Lambda \rightarrow \infty$ + \begin{align} + \text{Tr}(f(\frac{D_\omega}{\Lambda})) \simeq& \ 2f_4 \Lambda ^4 + a_0(D_\omega ^2)+ 2f_2\Lambda^2 a_2(D_\omega^2) \\&+ f(0) a_4(D_\omega^4) + +O(\Lambda^{-1}). + \end{align} + Note that the heat kernel coefficients are zero for uneven $k$, + furthermore they are dependent on the fluctuated Dirac operator + $D_\omega$. We can rewrite the heat kernel coefficients in terms of $D_M$, + for the first two we note that $N:= \text{Tr}\mathbbm{1_{H_F}})$ + \begin{align} + a_0(D_\omega^2) &= Na_0(D_M^2)\\ + a_2(D_\omega^2 &= Na_2(D_M^2) - \frac{1}{4\pi^2}\int_M + \text{Tr}(\Phi^2)\sqrt{g}d^4x + \end{align} + For $a_4$ we need to extend in terms of coefficients of $F$, look week9.pdf + for the standard version, + \begin{align} + &\frac{1}{360}\text{Tr}(60sF)= -\frac{1}{6}S(Ns + 4 + \text{Tr}(\Phi^2))\\ + \nonumber\\ + &F^2 = \frac{1}{16}s^2\otimes 1 + 1\otimes \Phi^4 - \frac{1}{4} + \gamma^\mu\gamma^\nu \gamma^\varrho\gamma^\sigma F_{\mu\nu}F^{\mu\nu}+\\ + &\;\;\;\;\;\;\;+\gamma^\mu\gamma^\nu\otimes(D_\mu\Phi)(D_\nu + \Phi)+\frac{1}{2}s\otimes \Phi^2 + \ \text{traceless terms}\\ + \nonumber\\ + &\frac{1}{360}\text{Tr}(180F^2) = \frac{1}{8}s^2N + 2\text{Tr}(\Phi^4) + + \text{Tr}(F_{\mu\nu}F^{\mu\nu}) +\\ + &\;\;\;\;\;\;\;+2\text{Tr}((D_\mu\Phi)(D^\mu\Phi)) + + s\text{Tr}(\Phi^2)\\ + \nonumber\\ + &\frac{1}{360}\text{Tr}(-60\DeltaF)= + \frac{1}{6}\Delta(Ns+4\text{Tr}(\Phi^2)). + \end{align} + Now for the cross terms of $\Omega_{\mu\nu}^E\Omega^{E\mu\nu}$ the trace + vanishes because of the anti-symmetric properties of the Riemannian + Cruvature Tensor + \begin{align} + \Omega_{\mu\nu}^E\Omega^{E\mu\nu} = \Omega_{\mu\nu}^S\Omega^{S\mu\nu} + \otimes 1 - 1\otimes F_{\mu\nu}F^{\mu\nu} + 2i\Omega_{\mu\nu}^S + \otimes F^{\mu\nu} + \end{align} + the trace of the cross term vanishes because + \begin{align} + \text{Tr}(\Omega^{S}_{\mu\nu} = \frac{1}{4} + R_{\mu\nu\varrho\sigma}\text{Tr}(\gamma^\mu\gamma^\nu) = \frac{1}{4} + R_{\mu\nu\varrho\sigma}g^{\mu\nu} =0 + \end{align} + and the trace of the whole term is + \begin{align} + \frac{1}{360}\text{Tr}(30\Omega^E_{\mu\nu}\Omega^{E\mu\nu}) = + \frac{N}{24}R_{\mu\nu\varrho\sigma}R^{\mu\nu\varrho\sigma} + -\frac{1}{3}\text{Tr}(F_{\mu\nu}F^{\mu\nu}). + \end{align} + Plugging the results into $a_4$ and simplifying we can write + \begin{align} + a_4(x, D_\omega^4) &= Na_4(x, D_M^2) + \frac{1}{4\pi^2}\bigg(\frac{1}{12} s + \text{Tr}(\Phi^2) + \frac{1}{2}\text{Tr}(\Phi^4) \\ + &+ \frac{1}{4} + \text{Tr}((D_\mu\Phi)(D^\mu \Phi)) + \frac{1}{6} + \Delta\text{Tr}(\Phi^2) + \frac{1}{6} + \text{Tr}(F_{\mu\nu}F^{\mu\nu})\bigg) + \end{align} + The only thing left is to plug in the heat kernel coefficients into the + heat kernel expansion above. \end{proof} \section{Fermionic Action}