Space-Time

Reference.
Albert Einstein explaining the energy-mass relationship
1932 split the atom
1932

Einstein’s Universe: Understand Theory of General Relativity
Deriving Einstein’s most famous equation: Why does energy = mass x speed of light squared?

The Maths of General Relativity (1/8) - Spacetime and Worldlines
The Maths of General Relativity (2/8) - Spacetime velocity
The Maths of General Relativity (3/8) - Geodesics
The Maths of General Relativity (4/8) - Metric tensor
The Maths of General Relativity (5/8) - Curvature
The Maths of General Relativity (6/8) - Energy fluxes
The Maths of General Relativity (7/8) - The Einstein equation
The Maths of General Relativity (8/8) - Summary and Applications

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Reference.
Pilots In History “The 45 Degree angle”
video at time = 5:00 , UFO became transparent and disappear in 10 -20 seconds , invisible to the human eye
UFO Visual Fade in / Out transparent
1931 Sir Francis Chichester’s
1989 Fred Lewis