Where/where

10:45 May 7, 2019 

Cheers. I was really just looking for that kind of confirmation. I usually just continue the sentence in the line below the equation, with "where" in lowercase, but I've never seen or been able to find any specific guidelines on the matter. I get peer reviewers' comments like that all the time too. In fact, a couple of my clients are now peer reviewers and I occasionally have to tidy up their ropey English for them, especially when they're criticising the work of other authors.

10:02 May 7, 2019 

A related factor that could be behind capitalising "Where" is that the text software could force an initial capital at the beginning of a new line. This type of parameter is not always easy to override, and many mathematical authors probably don't think it matters anyway. English is of course the international lingua franca of maths, and the English is sometimes pretty ropey. My friend, who cares enough to make sure his English is OK, gets me to check his answers to peer reviewers (usually over a beer), and their comments are sometimes very badly written.

09:53 May 7, 2019 

I regularly revise articles for a mathematician friend, and "where" should definitely be lower-case here. It is lower-case in every instance I've seen. I don't doubt that it's sometimes capitalised, but it shouldn't be.

As for whether it goes on a new line, bear in mind that maths texts use special software to cope with equations and other heavy-duty formatting issues, and in certain cases it may simply not allow them to run the text on in the same line as the equation, though it should. And some people may prefer their equation to stand alone, like an indented quotation. But in principle, "where..." should be run on. The comma should really be included but sometimes isn't, partly, I think, because people don't want anything immediately adjoining their equation.

09:34 May 7, 2019 

I found this example, where the comma appears on the same line as the equation, and the sentence continues below it:
The output voltage Vout is [Equation appears here],
where V0 is the voltage supplied to the bridge and R1 and R2 are resistances.

09:32 May 7, 2019 

Unfortunately, not all mathematicians are familiar with grammar rules.

09:27 May 7, 2019 

I'm aware of how grammar and syntax normally work; but equations as they appear in academic papers are a bit of a special case.

09:24 May 7, 2019 

… to clarify could be whether the "where" clause should be on the same line as the equation, or on a new line, as in the two example options below. It would also be interesting to know where to find resources providing guidelines about these little details.

09:22 May 7, 2019 

You can only start a sentence with "Where", where the sentence is a question. Phrases/titles like "Where the land meets the sea", "Where the Wild Things Are" can also start with "Where".