It said: "The History of every major Galactic Civilization tends to pass through three distinct and recognizable phases, those of Survival, Inquiry and Sophistication, otherwise known as the How, Why and Where phases.
“For instance, the first phase is characterized by the question How can we eat? the second by the question Why do we eat? and the third by the question Where shall we have lunch?” (C) DNA
I, personally, like space nice and curvy.
Enjoyable. But “tangent” to what? (Light cone as limited case.)
Tangent to a curve in spacetime. At each point or event in spacetime the set of vectors at that point makes up a vector space called a tangent space.
Got it. Google images is clear enough before I got stomped by Wiki.
Is “chronological time” some sort of “über time” felicitous to the theorist of multiple continua?
ETA: that phrase beginning with “felicitous” is pretty cool, if IDSSM
In most The chronological future of an event p is the set of all events intersected by future-directed timelike curves starting at p. The causal future of p is the set if all events intersected by future-directed timelike and null (‘lightlike’) curves.
In flat (Minkowski) spacetime the chronological future is the interior of the future light cone (notwithstanding what I said earlier about light cones) and the causal future is the light cone (the boundary and the interior).
The reason that the distinction is made between chronological and causal futures is simply because it is a useful distinction when talking theorems that apply to very general classes of spacetimes.
Thanks, thanks a lot. I now, at 1:23 in the wee hours, feel exceptionally old. I guess I’ll just try to sink into the covers and review my fond memories of rotary dialed phones, phonographs, landlines, TV’s with rabbit ears, snail mail, parachute pants, Huey Lewis and the News and last but not least my hair. I hope you’re happy now. Hmppphhh…