DOES THE NOT TO BE EXIST?

For Heraclitus to be and not to be are identical, things are and are not at the same time because everything flows continuously. Later Parmenides criticizes to Heraclitus saying that to be and not to be at the same time is absurd. For Parmenides only exists TO BE, but is static.
Being exists, is now, but being is not static as Parmenides believed, but flows.

HERACLITUS: TO BE and NOT TO BE

PARMENIDES: TO BE or NOT TO BE

BECOMING ------TIME (duality)
...TO BE ........... IT WAS

Time is a way of to BE (becoming) that groups several nows.