Here is the picture of the diagram:
How can I draw this diagram in Latex?
Welcome! tikz-cd
allows you to draw such diagrams. I am sure I did not decipher everything (just because some glyphs are hard to read) but you will probably find it easy to edit this code.
\documentclass{article}
\usepackage{amsmath}
\usepackage{dsfont}
\usepackage{tikz-cd}
\begin{document}
\[\begin{tikzcd}[row sep=2em,column sep=2.5em]
I\times I \arrow[drr,"\text{respect equivalence $\sim$}",bend left]
\arrow[dr,"\text{stretch}",bend left] \arrow[d,"q"] & & \\
M_* \arrow[drr,"\exists!m",bend right] & {}[0,2\pi]\times[-1,1] \arrow[r,"\bar u"] & \mathds{R}^3\\
& & M \arrow[u,"\cap_H"']\\
\end{tikzcd}\]
\end{document}
Welcome, there are many different ways to write this diagram with TikZ. Here, I use the matrix
library that was written to align the nodes
of a diagram.
\documentclass[border=5mm]{article}
\usepackage{amssymb}
\usepackage{tikz}
\usetikzlibrary {matrix}
\begin{document}
\begin{tikzpicture}
\matrix [matrix of math nodes,column sep=1.2cm,row sep=1cm]
{
|(I2)| I\times I & & \\
|(Me)|M_* & |(X)| [0,2\pi]\times[-1,1] & |(R)| \mathbb{R}^3 \\
& & |(M2)| M \\
};
\begin{scope}[every node/.style={midway,auto,font=\scriptsize}]
\draw [->] (I2) -- node {$q$} (Me);
\draw [->](X) -- node {$\bar u$} (R);
\draw [->](I2) to [bend left] node{stretch}(X);
\draw [->](I2) to [bend left] node{respect equiv. $\sim$}(R);
\draw [->](Me) to [bend right] node{$\exists !m$}(M2);
\draw [->](M2) --node[right]{$\cap_M$}(R);
\end{scope}
\end{tikzpicture}
\end{document}
Here's an alternative using xy.
\documentclass[border=5mm]{standalone}
\usepackage[all]{xy}
\usepackage{amssymb} % for the blackboard bold symbol
\usepackage{amsmath} % for \text
\begin{document}
\xymatrix{
I \times I
\ar[d]^{q}
\ar@/^/[dr]^{\text{stretch}}
\ar@/^20pt/[drr]^{\strut\text{respect equivalence}\thinspace\sim}
\\
M_*
\ar@/_12pt/[drr]_{\exists!m}
&
[0, 2\pi] \times [-1, 1]
\ar[r]^-{\bar{u}}
&
\mathbb{R}^3
\\
&
&
M \ar[u]_{{}\cap_M}
\\
}
\end{document}
\bar{u}
should have been \bar{\mu}
...
The dot lanquage from graphviz is a great for drawing commutative diagrams as you can see here : commutative diagram
One can use dot language from graphviz, the Python script dot2tex to convert into LaTeX and the dot2texi.sty package to include the dot code into a LaTeX document.
\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{shapes,arrows}
\usepackage{dot2texi}
\usepackage{amsmath,amssymb}
\begin{document}
\begin{dot2tex}[dot]
digraph T
{rankdir=TB;
ranksep=.2;
nodesep=.1 ;
node [shape=none];
1 -> 4 [dir=backward xlabel="q "];
1 -> 5 [label="stretch" constraint=false];
1 -> 6 [label="respect equiv. ~ " texlbl="respect equiv. $\sim$" tailport=e headport=no constraint=false];
4 -> 9 [constraint=false label="∃!m" texlbl="$\exists!m$"];
5 -> 6 [constraint=false label="μ " texlbl="$\bar\mu$"] ;
6 -> 9 [dir=back label="∩_M " texlbl="$\cap_M$"];
1 [label="I x I" texlbl="$I\times I$"];
{rankdir=LR ; rank=same
4 [label="M*"];
5 [label="[0,2Π]✕[-1,1]" texlbl="$[0,2\pi]\times[-1,1]$"];
6 [label= "R^3" texlbl="$\mathbb{R}^3$"]; }
9 [label="M"]; }
\end{dot2tex}
\end{document}
The tikzpicture environment created
dot2texi is a great package and can be used to produce very quickly a lot of diagrams in a declarative style.
Another way with plain TikZ: the firuge is just one \path
attaching with four node
s and connecting with arrows. The code is long and easy to read.
\documentclass{article}
\usepackage{tikz,amsmath,amssymb,lipsum}
\begin{document}
\lipsum[1]
Define $\bar\mu\colon [0,2\pi]\times [-1,1]\to \mathbb{R}^3$ with some formular as $\mu$.
\[
\begin{tikzpicture}
\path
(0,0) node (I) {$I\times I$}
++(-90:1.2) node (M1) {$M_*$}
++(0:3) node (M2) {$[0,2\pi]\times [-1,1]$}
++(0:2.5) node (M3) {$\mathbb{R}^3$}
++(-90:1.2) node (M4) {$M$}
;
\begin{scope}[->,nodes={midway,scale=.8}]
\draw (I)--(M1) node[left]{$q$};
\draw (I) to[out=0,in=120] node[above right]{stretch} (M2);
\draw (I) to[out=20,in=120] node[above right]{respect equivalence $\sim$} (M3);
\draw (M1) to[out=-50,in=-160] node[above]{$\exists ! m$} (M4);
\draw (M2)--(M3) node[above]{$\bar\mu$};
\draw (M4)--(M3) node[right]{\rotatebox[origin=c]{270}{$\subseteq$}$_\mu$};
\end{scope}
\end{tikzpicture}
\]
\lipsum[1]
\end{document}