Bit of a late comment, but 'This only exists in theory' is not always the same as 'This only exists on paper' in some dialects of English. At least here in the US Midwest, the 'in theory' version typically refers to something not being confirmed or to something that is only true in an idealized situation that ignores reality, while the 'on paper' version usually implies something has been designed but never implemented (for example, you have blueprints, but have never produced a prototype) but not necessarily that implementation is impossible (which is kind of implied by the 'in theory' version).
I just got this question and it is in the definite form. But, the question just before it was the same statement in English, but the answer was in the indefinite form. So, the first time, it was papper the second time it was papperet. I came here looking for an explanation as to why it was acceptable in the definite and indefinite.
No, because 'that' is treated as singular, it must be 'exists' with an 's'.
What you put could work as a subclause if there was something in front of it "They were talking about things that exist only on paper", (and it would be … som bara finns på papperet in Swedish) but it doesn't work on its own.
Thank you, my first sentence lacked a "that". Would be "there is that only on paper" better and acceptable?
I do not like the verb "exists" in the given translation. Why is it not possible to translate: "It is only on paper" or "It is just on paper" without the definite article instead of the given English standard solution?
For an expression like this suggested sentence to work in English, you would need a predicate nominative: "There is SOMETHING only on the paper," like coffee spilled and landed only on the paper. However, "det finns" can sometimes mean "it exists," and this lesson is about an imaginative idea, so "It exists only on paper." I have frequently heard this idea expressed as "It exists just on paper."