At 09:48 97-04-22, J%org Knappen, Mainz wrote: >... The following conventions are often >employed by physicists: > >Variables: math italics >Vectors: bold math italics >Operators: upright >Vector Operators: bold upright >Tensors: sans serif This is certainly goes in another direction than the math typesetting principles we discussed. In math, these should all then have been "leaning", if not constants. Otherwise, I think one in math just tries to "upper" the graphics with "larger" math objects, depending on the context (often overridden by tradition, then), or so, I think of it. The reason that vectors are often typeset in bold, and not bold italics could be that formerly one practise was to indicate, in a hand written manuscript, two levels of emphasis by single or double underlining, which then was interpreted by the typesetter as italic and bold (so the author did not have much control over it). But if you decide to typeset tensors upright sans serif, then the Christoffel symbol, which normally is an upper case $\Gamma$, should be typeset like that too. (But using a $\Gamma$ for the Christoffel symbol is so standard, it should perhaps be typeset upright anyhow.) Hans Aberg