Depends. More recently we tend to cooperate, but one of the reasons why Europe had such a rapid industrialization era is because they borrowed the basics from neighboring countries.

When countries are at war, they usually give their Ally their scientific discoveries to keep up the pace. Like you said the US & USSR are great examples of these.

But then you have stuff like library of Alexandria, or really a lot of the colleges/schools built in the old world which shows for the most part we probably were exchanging knowledge for a very long time.

Knowledge is highly prized in the Middle East so it makes sense that’s where a lot of the exchanges uses to happen.

Calculus is a good example of people discovering things on their own. Newton & Leibinz technically found out about it at the same time, Leibinz just popularized it.

Results might have different methods that lead up to their discovery due to different ethical guidelines and that’s when you can argue two people discovered things at different times. It’s truly one of the reasons we have to file patents and why patent law is soooo lucrative.

Idk if this helps 😶‍🌫️