nLab
Sandbox

Every wiki needs a sandbox! Just test between the horizontal rules below (*** in the source) and don’t worry about messing things up.

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First

$\leftrightarrow$

The first section

Second

The second section

Third

Can we fix it?

Theorem

Correct behaviour

Theorem

1. A list, with
2. Incorrect behaviour

Theorem

A comment to one side

The theorem

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A link to the Sandbox.

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Another link to the Sandbox.

1. The first item
2. The second item

Can we refer to \ref{first} or \ref{second}?

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Why has this elementary topos stopped working?

$$\widehat{ℂ}\underset{\underset{f_{*}}{\overset{\perp }{\to }}}{\overset{\underset{\perp }{\overset{f_{!}}{\to }}}{⟵f^{*}-}}\widehat{𝔻}$$\widehat{\mathbb{C}} \, \underoverset{\underoverset{f_{*}}{\perp }{\rightarrow }}{\underoverset{\perp }{f_{!}}{\rightarrow }}{\longleftarrow \scriptsize f^{*} - \,} \widehat{\mathbb{D}}

$$ℰ\underset{\underset{f_{*}}{\overset{\perp }{\to }}}{\overset{\underset{\perp }{\overset{f_{!}}{\to }}}{⟵f^{*}-}}ℱ$$\mathcal{E} \underoverset{\underoverset{f_*}{\perp}{\rightarrow}}{\underoverset{\perp}{f_!}{\rightarrow}}{\longleftarrow {\scriptsize f^*} -} \mathcal{F}

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What about anchors in lists?

• The first

• The second

• The second and a halfth

• The third

• The fourth

• The sixth

By a mechanical process, this definition can be turned into a definition of ’internal field in a topos’. As compensation for the imprecision of the rest of this section, I will give the definition in detail; but if you want to skip it, the point to retain is that it is a mechanical process.

By a mechanical process, this definition can be turned into a definition of ‘internal field in a topos’. As compensation for the imprecision of the rest of this section, I will give the definition in detail; but if you want to skip it, the point to retain is that it is a mechanical process.

a-b a–b a—b

a‐b a‑b a‒b a–b a—b a℅b

$$\underset{n\to 0}{\lim }\frac{1}{n}=0$$\lim_{n \to 0} \frac{1}{n} = 0

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Hi

proper homotopy theory (unbroken copy)

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$\hat{\otimes }$ in the same line with $\hat{x}$, $\hat{x}$ $\hat{\otimes }$, $\hat{\otimes }$, $\overline{\otimes }$ ${\displaystyle \hat{\otimes }}$ $\hat{x}$

$$\hat{\otimes }\hat{\times }$$\hat{\otimes} \hat{\times}

$$\underset{a}{\overset{b}{\Rightarrow }}\stackrel{[}{\Rightarrow }a]b\stackrel{[}{\Rightarrow }a]b\underset{a}{\overset{b}{\Rightarrow }}$$\xRightarrow[a]{b} \xRightarrow [a]{b} \xRightarrow [a]b \xRightarrow[a]b

reflective? subcategory

*reflective* subcategory

<em>reflective</em> subcategory

A test of underlining, with punctuation

A test of underlining, with punctuation

A test of underlining, with punctuation

A test of underlining, with punctuation

Only it wasn’t underlining, it was emphasis.

category: meta