Einsteins #GeneralRelativity predicted that massive objects like the sun should bend light with their massive gravity. Photos of stars at night versus during an eclipse show this effect.
I keep seeing the news about lunar time presented as “the Moon is getting its own time zone." What's actually happening is the Moon is getting its own time standard. The problem being solved is that time passes slightly more quickly on the Moon compared to Earth (due to General Relativity) and so the Moon needs its own time standard for precise measurements and navigation. UTC is the time standard for measuring time on Earth, and LTC is being created for the Moon.
If you're curious why time passes more quickly on the Moon, it's this: https://en.wikipedia.org/wiki/Gravitational_time_dilation Because Earth's gravity is higher, there’s more time dilation than on the Moon (by about 58.7 microseconds per day, or 2.144 seconds per century).
One way to think about it is that the local neighborhood of spacetime for someone standing on the Earth's surface is boosted (“tilted”, in a 4D sense) relative to that for someone far away from any massive body.
The Tenth Doctor: People assume that time is a strict progression of cause to effect, but actually, from a nonlinear, non-subjective viewpoint, it's more like a big ball of wibbly-wobbly, timey-wimey... stuff.
‘Wobbly spacetime’ may help resolve contradictory physics theories
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#onthisday in 1915: Albert Einstein submitted a paper to the journal "Sitzungsberichte der Preussischen Akademie der Wissenschaften zu Berlin" that would fundamentally alter our understanding of the universe [1]. The four page paper contained what became known as the Einstein field equations, which relate the geometry of spacetime to the distribution of matter within it [2].
Einstein's field equations were presented in the form of a tensor equation which related the local spacetime curvature (expressed by the Einstein tensor) with the local energy, momentum and stress within that spacetime (expressed by the stress–energy tensor) [3].
Scientists have discovered that cosmic structures grow slower than Einstein's Theory of General Relativity predicts, with dark energy playing a more dominant inhibitory role than previously thought. This finding may reshape our understanding of dark matter, dark energy, and fundamental cosmic theori
Quasar 'clocks' show the universe was five times slower soon after the Big Bang
"Looking back to a time when the universe was just over a billion years old, we see time appearing to flow five times slower"
…
"If you were there, in this infant universe, one second would seem like one second—but from our position, more than 12 billion years into the future, that early time appears to drag."
Well, since we are bracing for the impact of an imminent major announcement on pulsars and, maybe, some gravitational wave background, why not enjoy this 2004 special Science Magazine issue on pulsars!
Universe Defies Einstein’s Predictions: Cosmic Structure Growth Mysteriously Suppressed (scitechdaily.com)
Scientists have discovered that cosmic structures grow slower than Einstein's Theory of General Relativity predicts, with dark energy playing a more dominant inhibitory role than previously thought. This finding may reshape our understanding of dark matter, dark energy, and fundamental cosmic theori