Spinors in the Dirac ideal are given by $$\begin{aligned}
N &= M \frac{1+\gamma_0}{2} \frac{1+\gamma_5\sigma_3}{2} \
&= (M_+ + M_-)\frac{1+\gamma_0}{2} \frac{1+\gamma_5\sigma_3}{2} \
&= (M_+ + M_-\gamma_0)\frac{1+\gamma_0}{2} \frac{1+\gamma_5\sigma_3}{2} \
&= M_+'\frac{1+\gamma_0}{2} \frac{1+\gamma_5\sigma_3}{2} \
&= (\text{Re}M_+' + \text{Im} M_+' I \sigma_3)\frac{1+\gamma_5\sigma_3}{2}\frac{1+\gamma_0}{2} \
&= \psi \frac{1+\gamma_5\sigma_3}{2}\frac{1+\gamma_0}{2} \
\end{aligned} $$where
Let $$ \begin{gathered} \gamma_0 = \begin{bmatrix} 0 & - i I_2 \ i I_2 & 0 \end{bmatrix} = -i \beta \ \gamma_1 = \begin{bmatrix} -i\sigma_3 & 0 \ 0 & i\sigma_3
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| const { RecursiveResolver, dnssec, wire: { Record, types } } = require('bns') | |
| const port = 5349 | |
| const resolver = new RecursiveResolver() | |
| resolver.setStub('127.0.0.1', port, hnsDS()) | |
| resolver.on('log', console.log) | |
| resolver.on('error', console.error) | |
| resolver.lookup('com', types.A).then(console.log).catch(console.error) |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| ### A Pluto.jl notebook ### | |
| # v0.16.1 | |
| using Markdown | |
| using InteractiveUtils | |
| # This Pluto notebook uses @bind for interactivity. When running this notebook outside of Pluto, the following 'mock version' of @bind gives bound variables a default value (instead of an error). | |
| macro bind(def, element) | |
| quote | |
| local el = $(esc(element)) |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| # Put this in your espanso config folder and run `julia latex-completions.jl` to add all Julia REPL completions to espanso. | |
| # Note: each expansion includes a space at the end (otherwise e.g. \c will autocomplete before you finish typing \cdot). | |
| # You can try using a tab to trigger: "\\\\$(word[2:end])\t" instead, but this led to some unpredictable behavior for me. | |
| # https://github.com/JunoLab/atom-latex-completions/blob/master/completions/generate.jl | |
| import REPL | |
| open(joinpath(dirname(@__FILE__), "user/latex-completions.yml"), "w") do io | |
| println(io, "name: latex-completions") |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| chrome.contextMenus.create({ | |
| title: 'Open Frame in New Tab', | |
| contexts: ['frame'], | |
| onclick: ({ frameUrl }) => { | |
| chrome.tabs.create({ | |
| active: false, | |
| url: frameUrl | |
| }) | |
| } | |
| }) |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| macro require(mod) | |
| try | |
| Base.require(__module__, Symbol(mod)) # like require("module") | |
| catch e | |
| mod = string(mod) | |
| include(mod) # like require("./module.js") | |
| end | |
| end | |
| macro assign(ex) |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| hello world |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Rendered $\LaTeX$ from [Github Gists](https://gist.github.com/) |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| So…this is the expression I’m finding for the “inhomogeneous” equations: | |
| $\nabla_\mu R^{\mu \nu}_{ \rho \sigma} = J^\nu_{\rho \sigma}$ where $J^\nu_{\rho \sigma} \equiv \nabla_\mu W^{\mu \nu}_{\rho \sigma} + \nabla_{[\rho} t_{\sigma]}^\nu$, $t_{\mu \nu} = \frac{1}{2} T_{\mu \nu} - \frac{1}{3} g_{\mu \nu} T$, and $T$ is the trace of $T_{\mu \nu}$. I think this can be placed entirely in terms of $T_{\mu \nu}$ using self-duality of the Weyl tensor. | |
| And I expect the "electric" and "magnetic" fields to be given by $E_{i \rho \sigma} = R_{0 i \rho \sigma}$ and $B_{i \rho \sigma} = -\frac{1}{2} \epsilon_{ijk} R^{jk}_{\rho \sigma}$. | |
| I think the only real dent in the analogy is that $J^\nu_{\rho \sigma}$ is not a conserved current in general. |
NewerOlder