Comment on 8 Minutes
zea_64@lemmy.blahaj.zone 2 months ago
If the sun disappears when? According to GR’s conception of simultaneous events, it disappears immediately.
Comment on 8 Minutes
zea_64@lemmy.blahaj.zone 2 months ago
If the sun disappears when? According to GR’s conception of simultaneous events, it disappears immediately.
tate@lemmy.sdf.org 2 months ago
Which two event are you talking about being simultaneous? The Sun going out and Earthers observing it? Those things will not be simultaneous in any reference frame, because they are “light-like” separated.
WolfLink@sh.itjust.works 2 months ago
I think what he means is when the light from the sun disappearing arrives at earth, that’s effectively when the event of the sun disappearing happened from the earth’s perspective.
zea_64@lemmy.blahaj.zone 2 months ago
wait, who’s he?
Zink@programming.dev 2 months ago
Yep. Imagine you’re off in space such that you, the sun, and the earth make an equilateral triangle. The sun disappears, then after 8 minutes you see it disappear. Then after ANOTHER 8 minutes you see the earth go dark, because that light had to cover two of the 8-light-minute long legs of the triangle.