basic science and slashes doesnt push u back
who told u that? a science teacher?
who told u that? a science teacher?
anyway, ill still tell you the physics behind it
when something hit you, that something transfers its energy to you, in the case of punch, the energy is transformed into kinetic energy since the energy it carries cover a wide area, so the distribution of the energy is not enough to rupture your body (transforming its energy into your body's atom potential energy). But with slashes, for the same amount of energy, it covers a small area, so the distribution of the energy is dense and is more than enough to rupture your body, so instead of pushing you back (kinetic energy), it pierces your body (the energy is used to breaking apart the potential energy of the atoms)
i dont need ur opinion. zoro couldnt push back kaido or even put him down remotely even with his strongest attack. while pre udon luffy did that. either u cope or accept zoro is yet to reach that level