This question is similar to
However, I seek an answer in the context of the laws of the European Union (not, necessarily, any specific country) and, also, specifically in the science context. To make my question even more distinct, I will provide a specific use case that is, hopefully, sufficiently different from the use cases in the aforementioned questions.
Suppose, a person P would like to create "lecture notes" based on a science textbook. The notes are meant to be used for private study and non-commercial research use only. A significant part of the content of the textbook expresses reasonably well-known ideas (i.e. other books that express similar ideas seem to exist) and P would not be copying the content word-for-word. Nonetheless, it is likely that there will be very significant overlap and resemblance in terms of the structure and content of the textbook and P's notes.
I would like to understand whether P recording such notes would be legal. What about their distribution to third parties (again, under the premise of non-commercial research/study use only)?
It seems likely that my use case would fall under "Fair use" in the US. However, I find it difficult to interpret the European legalese.
I would also like to understand what laws are actually applicable in this case. The laws of the country of the copyright holder/publisher? The laws of the country where P resides? The laws of the country where the content is hosted? The laws of the country/countries where the content is available?