# How to make the math font slightly thicker?

I'd like to use TeX Gyre Schola as my text font and the default LaTeX font for the math mode. (Side question: is the default font Latin Modern in math mode or another font?)

MWE:

\documentclass[fleqn]{scrartcl}
\usepackage{tgschola}
\usepackage[T1]{fontenc}

\begin{document}
This is some text.
$F_\mathrm{D} = m \ddot z = b \lambda \rho \frac{I}{P_0} \vec{c}$
Sadly, the math is less thick than the text.
\end{document}


While both look great on their own, IMHO, the drawback is that the math font is much more "thin" or less "thick" than the text font.

Is there a way to keep this math font and make it slightly thicker, but not bold, with pdfLaTeX?

-
Nice question! I'd like to know if there is a way to locally make certain math characters slightly thinner. For example, the letter $\Psi$ looks almost bold by default and so stands out on a page; it's kinda ugly. –  User 17670 Apr 21 '13 at 18:17
If you don't load unicode-math or any math font package, then Computer Modern will be used, which doesn't really match with New Century Schoolbook. You could try \usepackage{fouriernc} –  egreg Apr 21 '13 at 22:34
@egreg fourier + tgschola looks a lot different from fouriernc (both in text and in math). I like tgschola much more. But the "officially" matching fourier has some rather big spaces on some sub- and superscript combinations that look rather strange without lots of manually tweaking. That's why I wanted to try something different. –  Foo Bar Apr 22 '13 at 6:58

(Note: After my answer, the OP specified that a pdfLaTeX solution is wanted.) Xe(La)TeX offers the FakeBold font feature -- meant for "rare situations [when] users may want to mechanically distort the shapes of the glyphs in the current font" (fontspec manual, section 10.13). Use at your own risk. ;-)

% !TEX TS-program = XeLaTeX

\documentclass[fleqn]{scrartcl}

\usepackage{fontspec}
\usepackage{unicode-math}
\setmainfont{TeX Gyre Schola}
\setmathfont[FakeBold=0.5]{Latin Modern Math}

\begin{document}
This is some text.
$F_\mathrm{D} = m \ddot z = b \lambda \rho \frac{I}{P_0} \vec{c}$
Sadly, the math is less thick than the text.
\end{document}


Output without FakeBold:

-
So, there's no pdfLaTeX way? –  Foo Bar Apr 22 '13 at 6:58
@FooBar I don't know. –  lockstep Apr 22 '13 at 9:31

Just use:

\usepackage{fouriernc}


or

\usepackage{millennial}


or

\usepackage{fourier}


\usepackage{tgschola}

I don't know about millennial; I know fourier, but it uses Utopia, rather than New Century Schoolbook (they aren't the same font). On the other hand, fouriernc provides a math font for New Century Schoolbook that can be used along with tgschola: all is needed is to load fouriernc before tgschola. –  egreg Oct 27 '13 at 21:11