Greetings To be straight, I've been studying Goldstein Classic mechanics. While studying, it turned out that this is not a book for my level,(knew it would be challenging, but even far beyond) but even after finding out that something is wrong, i kept studying this book, by doing some research or repeating the hard part endlessly. Except for few things on chapter 5 and 6, I managed to read and understand to the level that i won't give up (could be poor understanding though) But the reason why I'm asking this requirement stuff now is because I can't read further...I got stuck in chap. 7: relativity... Descriptions started to skip things quiet a lot than usual, and my understanding seems to be especially weak at this topic's skipping. ( apparently not prepared) After being stopped, i kinda regret reading this book this far....but still can't give up that easily So anyway, what i want to ask is, 1. Is there any specific topic on mathematics that would help me study relativity on Goldstein? (I studied bit of linear algebra before studying chap. 4,5,6 and it had been very helpful) 2. If you have a experience of goldstein Classic mechanics, do you have any branch of mathematics in mind, that would be necessary for reading goldstein? 3. Do you have any suggestion for math book? (linear algebra? advanced calculus?) 4. Should I just skip chap. 7? Do you think it is a good idea? ( actually is it classic?) 5. Should I stop reading this book?