# Greek letter in the notation for martingale problem

This is nothing but just a question about greek letters in the notation of III.1.9 in Jacod and Shirayeav (2003):

In here, what is the letter ? and how can I write in LaTeX?

It would be very appreciated if you let me know.

Thanks,

• It is not a greek letter. Looks like a calligraphic lowercase s. Commented May 13, 2021 at 17:58
• Thank you very much! Commented May 13, 2021 at 18:33

Using pdfLaTeX with the package calligra:

\documentclass[a4paper,12pt]{article}
\usepackage{newtxmath,newtxtext}
\usepackage{mathrsfs}
\usepackage{calligra}
\usepackage[T1]{fontenc}

\begin{document}
$\mbox{{\calligra s}}\,(\mathscr{H},\mu\mid P_H,\nu)(abc)$
\end{document}


Like @Bernard said, its calligraphic lowercase s \mathscr{s}.

With TeX Gyre Schola Math font

$\mathscr{s}(\mathscr{H}, μ \big|\mathit{P_{H}}, ν)$

looks like this:

% !TEX TS-program = xelatex
% !TEX encoding = UTF-8 Unicode
\documentclass[12pt, a4paper]{article}
\usepackage{fontspec}
\setmainfont{TeX Gyre Heros}
\usepackage{unicode-math}
\setmathfont{TeX Gyre Schola Math}
\usepackage{polyglossia}
\setmainlanguage[variant=british]{english}

\begin{document}

$\mathscr{s}(\mathscr{H}, μ \big|\mathit{P_{H}}, ν)$

\end{document}


Greeks letter can be set also with $\mu \nu$.

• I think the last letter is \nu instead of v. Commented May 13, 2021 at 18:43
• $v \nu$ (v and ν)
– Oni
Commented May 13, 2021 at 18:58
• Yet, in OP's picture, if you have a close look, i really think it's a \nu, but one can choose what he wants ;) Commented May 13, 2021 at 19:00