The notion of Local Inertial Frame is crucial to understanding Nature and in particular General Relativity. Notwithstanding very few popular science books not even textbooks emphasize enough its fundamental character.

Advertising Disclosure: Please note that many links to retailers are affiliate links, which yields a commission for us. allauthor.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon sites.