SRT: "space AND time" and "spacetime"
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a)
The "space AND time" is gravity reference frame where space
is constant but time for inhabitants can "flow".
b)
The " spacetime" is reference frame without gravity.
There isn't gravity in " spacetime".
This reference frame was called " Minkowski absolute negative
pseudo-Euclidean 2D continuum ". In this reference frame "space"
and "time" are frozen, constant , doesn't "flow".
It is an eternal state of vacuum continuum as for "space" and as well
for habitants so called "negative virtual particles".
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