All We Know about Physics of Time in 4 Pages

Since Einstein and since the first GPS system failure, we know that time speed is not constant, as our senses tell us, and as Newton thought. Here I give an overall perspective on this subject plus some new insights. I refer to chapters in my <a href="https://drive.google.com/file/d/1ov2_q7lnXf42OZS2PII_jsn3vEje_Pd4/view" rel="noopener ugc nofollow" target="_blank">free eBook</a> (also available on <a href="https://play.google.com/store/books/details?id=2yZ6EAAAQBAJ" rel="noopener ugc nofollow" target="_blank">Google</a> and <a href="https://www.amazon.com/dp/B0CKTFKBF4" rel="noopener ugc nofollow" target="_blank">Amazon</a>), where you can get more details, but it is not required for understanding this article. In chapter 58, we demonstrated how Newton’s 1st (inertia) law “object remains in motion at constant speed unless acted on by a force” is violated when crossing timezones: <a href="https://medium.com/timematters/all-we-know-about-physics-of-time-in-4-pages-a5273a150a7e">Website</a>