One management tool for all smartphones to transfer files between PC & iOS/Android devices.
Go to your preferred bookstore or library. Verify the "Revised printing" date. Download the legitimate PDF. Set aside two hours per day for ten weeks. And when you finally derive the Schwarzschild radius from scratch, you will know why 300,000 people have searched for this exact document.
The Theoretical Minimum is a series created by world-renowned Stanford physicist Leonard Susskind . Unlike popular science books that skip the math, this series provides the absolute minimum level of mathematical rigor—calculus, tensors, and differential equations—needed to actually do physics.
The hunt for is a rite of passage. But remember: A PDF is just dead ink until you compute your first Christoffel symbol.