Using "thereby" to express concurrency

Question

I'm currently reviewing a thesis by a student who's native language is German (like mine as well). They are often using "thereby" to express concurrency, as in

Fritz walked down the street; thereby he was whistling a song. (meaning: Fritz walked down the street while whistling a song)

To me this sounds like direct (and wrong) translation of the corresponding German sentence

Fritz ging die Straße entlang; dabei pfiff er ein Lied.

My intuition tells me that "thereby" should be used for things like causal relations, which would mean in the sentence above that Fritz's walk caused the whistling, but my intuition might be wrong as well. That said I have looked at some usage examples of "thereby" and none of them expressed the "concurrency" in the way the German "dabei" does.

Can "thereby" be used that way? If yes, is it appropriate for a scientific thesis? If no, what would be a nice replacement (in the best case one that preserves the sentence structure)?

Answer 1

No, it certainly can't - it's a 'false friend'. Thereby means 'by means of this'- I walked home, thereby saving myself the bus fare.

It would be sufficient to say Fritz walked down the street whistling a song.

Answer 2

"thereby" means,

• By that means; as a result of that.

"He slipped off the pavement, thereby spraining his ankle"
"She opened the gate, thereby allowing the dog to escape."

So no - it wouldn't be used there.

[By the way, we tend to whistle tunes, not songs. Songs have tunes you can whistle and words you can't.]

Your student has a range of alternatives:

"Fritz whistled a tune as he walked down the street"
"Fritz walked down the street, whistling a tune (as he went)"
"As he walked down the street Fritz whistled a tune"
"Walking down the street Fritz whistled a tune"

Or

"Whistling a tune Fritz set off down the street"

Using "set off" allows Fritz to stop whistling if it's a long street!

Answer 3

Looks like a literal translation of "dabei" - according to Wiktionary it can mean "thereby" sometimes, but it has other meanings in German that don't equate with "thereby" in English. One could say it's a false cognate (sometimes). So, yeah - looks like a translation error.

What should it be? Google translate says:

Fritz walked down the street; while he was whistling a song.

Maybe a German speaker could confirm this as I don't trust Google translate. I know a little German, but I'm no expert. It certainly works in English. You could also say "as he was whistling a song", but "therefore" is definitely incorrect here. In English "thereby" means "as a result of that", which doesn't make much sense here at all.