The abundance of matter and antimatter implies the laws of nature are different for particles and antiparticles. This is shown in the way more b mesons than anti-b mesons decayed into kaons and pions - the weak force does not conserve charge/parity. But if CP symmetry is not conserved, does this explain the arrow of time? Particle events, when reversed, would not be a mirror image of events in 'forward' time. Is there any explanation for why this is so?