Hypothetically. If a hole was drilled, with some super super strong mterial to line the walls and hold it open, right through the planet, at the precise centre, and out through the other end. Would there be any downward pull within the shaft? If you were suspended over the hole by a rope, would the absence of any solid matter between you and the antipodean sky at the other side make you weightless? Or would you be pulled in to sides and down?