I am attempting to learn GR (for fun) using Sean Carroll's text. I have made it ALL the way to . . . . page 9:surprised(adsbygoogle = window.adsbygoogle || []).push({});

I don't understand the equation on the bottom of page 9; (1.16) (namely, why there are TWO delta x ^u and delta x^y; but to type out my question I will need to know how you guys format in Physics notation. Can someone give me a link to that thread and then I will return here and type my question more appriopatly.

(If someone thinks they can understand my question anyway and wants to answer it; it is this. W have a 4x4 matrix (the n with the uv lower idicie) mulitplied by a 4x1 matrix delta x^u which itself is a single scalar which is exactly the spacetime interval (equation 1.10 on page 7). BUT, there are two delta x ^ u/v. What's up with that???)

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# Already confused with GR

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