The paradox of Minkowski space: Imaginary unit i is not a number but an action sign

"The paradox of Minkowski space: Imaginary unit i is not a number but an action sign"

from https://physicsessays.org/browse-journal-2/product/2067-4-andrey-yurievich-nechitaylo-the-paradox-of-minkowski-space.html

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