I agree that the problem is hard. However, biological brain is able to handle it quite "easily" ( is not really easy - bilions of iterations were needed ). The current brains are solving this 3D physical world _only_ via perception.

So this is place were we must look. It starts with the sensing and the integration of that sensing. I am working at this problem since more than 10 years and I came to some results. I am not a real scientist but a true engineer and I am looking from that perspective quite intesely: The question that one must ask is: how do you define the outside physical world from the perspective of a biological sensing "device" ? what exactly are we "seeing" or "hearing"? So yes, working on that brought it further in defining the physical world.