For the current span of my life I have continuosly checked for definitions of "energy" and probably seen them all. The net result in my experience is that aside from semantics, no idea of what energy actually is exists.
I would appreciate, in light of the fact that it is unknown, any though...
The Moon phases can be defined by the phase angle between the Sun, Moon and Earth; for example, at 0°, the Moon is defined as full, and at 180° it is defined as new. If you want to know how bright the Moon is at a given angle, we would use the phase angle to find the apparent and absolute magnitu...
How does the Hubble parameter change with the age of the universe?
This question was posted recently, and I had almost finished writing an answer when the question was deleted. Since it's a shame to waste the effort here's the answer anyway.
Maybe this can be one of the canonical answers sugges...
PBS Space Time recently had a challenge question involving two different proposed solutions to saving the earth from being trapped inside a Kugelblitz. https://www.youtube.com/watch?v=v3hd3AI2CAA
They also released the solution video https://www.youtube.com/watch?v=q_oHv6HCMX4
The short of it:
...
I know about this theory but I cannot get the picture that how moving faster than light even 100.01% of light-speed would make universe run backward.
