ASYMMETRIC time dilation (moving clock is slow, stationary one is fast):

https://youtu.be/Q1y3YnPgaY4?t=1157

That was non sequitur (didn’t follow from Einstein’s 1905 postulates) but the implication was TIME TRAVEL INTO THE FUTURE - a miracle (idiocy) that converted Einstein into a deity:

Thibault Damour: "The paradigm of the special relativistic upheaval of the usual concept of time is the twin paradox. Let us emphasize that this striking example of time dilation proves that time travel (towards the future) is possible. As a gedanken experiment (if we neglect practicalities such as the technology needed for reaching velocities comparable to the velocity of light, the cost of the fuel and the capacity of the traveller to sustain high accelerations), it shows that a sentient being can jump, "within a minute" (of his experienced time) arbitrarily far in the future, say sixty million years ahead, and see, and be part of, what (will) happen then on Earth. This is a clear way of realizing that the future "already exists" (as we can experience it "in a minute")." http://www.bourbaphy.fr/damourtemps.pdf

Einstein’s 1905 postulates entailed SYMMETRIC time dilation - either clock is slow as judged from the other clock’s system. The concept was sterile (no prediction) so Einstein fraudulently introduced non sequitur, ASYMMETRIC time dilation - moving clock is slow, stationary one is fast:

Albert Einstein, On the Electrodynamics of Moving Bodies, 1905: "From this there ensues the following peculiar consequence. If at the points A and B of K there are stationary clocks which, viewed in the stationary system, are synchronous; and if the clock at A is moved with the velocity v along the line AB to B, then on its arrival at B the two clocks no longer synchronize, but the clock moved from A to B lags behind the other which has remained at B by tv^2/2c^2 (up to magnitudes of fourth and higher order), t being the time occupied in the journey from A to B." http://www.fourmilab.ch/etexts/einstein/specrel/www/

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