Is this expression "whose definition" idiomatic?

Question

I asked a question just now

I am learning 𝐿𝑝 space, whose definition is based on function spaces.

Is this expression "whose definition" idiomatic?

Answer 1

Yes, although it is extremely common to use forms of who in this way.

"𝐿𝑝 space" isn't a who, and so whose doesn't really fit for it. A more correct phrasing would be something like

I am learning 𝐿𝑝 space, the definition of which is based on function spaces.

or

I am learning 𝐿𝑝 space, which has a definition based on function spaces.

If you were anthropomorphizing "𝐿𝑝 space", use of whose could be appropriate, but that's a very specific and very unusual case.

But people (in an American English context) are very lax with this type of rule, and relatively few people bother to get it right or would notice and care about the mismatch. Depending on where you are, the correct construction (like the definition of which) can seem overly fussy and formal. The idiomatic version is much more common, in my experience.

Answer 2

Since "𝐿𝑝 space" is a thing, but not a person, I would not use "whose" although I have seen math texts use "whose" in similar constructions. I would recast the sentence as one of:

• I am learning 𝐿𝑝 space, the definition of which is based on function spaces.
• I am learning 𝐿𝑝 space, which has a definition based on function spaces.
• I am learning 𝐿𝑝 space, which is defined based on function spaces.
• I am learning 𝐿𝑝 space: its definition is based on function spaces