How Einstein revolutionized the meaning of "where" and "when"

"We now recognize that even ideas like "when" and "where" are subject to the laws of Einstein's relativity, and that in relativity, space and time are not absolute quantities, but rather are relative to each and every unique observer."

"When you're observing an event here on Earth, you're not observing what's actually occurring "right now" in whatever direction you're looking at. Instead, you're observing what was occurring when the signal - whatever it may be - that's arriving in your eyes (or whatever organ or instrument you're using to measure it) right now was generated."

"We can still use our old, Newtonian notions of "where" and "when" for most practical purposes, but when it comes to the incredible precision required by modern science, or with distant objects within the expanding Universe, Einstein's revolutionary ideas of relativity must be incorporated."

Earth-based location and timekeeping systems rely on the assumption that all observers share the same present moment, an assumption disproven by Einstein's relativity over a century ago. Space and time are not absolute but relative to each observer's reference frame. While Newtonian concepts of location and time suffice for everyday purposes, modern science and observations of distant universe objects demand incorporation of relativistic principles. When observing any event, observers receive signals generated in the past, not witnessing simultaneous occurrences. This fundamental distinction between signal arrival and actual event timing becomes critical for achieving the precision required in contemporary scientific endeavors.

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