Why Does the World Exist?: An Existential Detective Story by Jim Holt Read Free Book Online Page A

singleton world would violate one of the bedrock principles of physics: the law of charge conservation. The net charge of the pair world sums up to zero, since the positron has charge +1 and the electron has charge –1. The net charge of the singleton world is +1. So moving from the pair world to the singleton world is tantamount to the creation of a net charge—a physical impossibility. Although the electron and positron are individually contingent, each is existentially linked to the other by the law of charge conservation.
    Then how about moving from the pair world directly to nothingness? Alas, that’s not physically possible either, for eliminating the electron-positron pair would violate another bedrock principle of physics: the law of mass-energy conservation. Some new entity—a photon, say, or another particle-antiparticle pair—would have to appear in their wake, as a matter of physical necessity.
    The hitch here seems to be the same one that both Bergson and Rundle encountered, but in a different guise. In all three cases, absolute nothingness is thought of as a limit , one to be approached from the world of being. Bergson tried to approach it by imaginatively annihilating the contents of the world, only to be left with his own consciousness. Rundle tried a similar imaginative route and also fell short of the goal, ending up with an empty spatial container. Both concluded that absolute nothingness was inconceivable. The subtraction argument tries a different tack, seeking to reach nothingness via a series of logical moves. But the reasonable-sounding intuition behind the subtraction argument— if there are some objects, there could have been fewer of them —runs afoul of a set of fundamental physical principles: the laws of conservation. And even if those laws were somehow suspended, it is by no means clear that the world’s ontological census could be steadily reduced by decrements of one, all the way down to zero. Perhaps the absence of one thing, in either imagination or reality, always entails the presence of another. Delete George Bailey from the scheme of things and up pops Pottersville.
    The apparent moral is this: it’s no simple matter to get from Something to Nothing. The approach is asymptotic at best, always falling short of the limit, always leaving some remainder of being, however infinitesimal. But is that surprising? To succeed in reaching Nothing from Something, after all, would be to solve the riddle of being in reverse. Any logical bridge from one to the other would presumably permit two-way traffic.
    If it seems easier in the imagination to get from Something to Nothing than the reverse, that’s because both the starting point and the terminus are known in advance. Suppose you sit down at a computer terminal in the reading room of the New York Public Library on Forty-second Street. There’s a single character on the screen—say, “$.” You press the delete button, and the screen becomes blank. You have effected a transition from Something to Nothing. Now suppose you happen to sit down at a terminal with a blank screen. How do you go from Nothing to Something? By pressing the undelete button. When you do so, however, you have no idea what will appear on the screen. Depending on what the previous user was up to, it could be a lapidary message or a mere jumble of characters. The transition from Nothing to Something seems mysterious, because you never know what you’re going to get. And the same is true at the cosmic level. The Big Bang—the physical transition from nothing to something—was not only inconceivably violent, but also inherently lawless. Physics tells us that there is in principle no way of predicting what might pop out of a naked singularity. Not even God could know.
    Instead of struggling to cross an impassable conceptual divide between Something and Nothing, it might be more profitable to forget about the world of being and concentrate on nothingness instead. Can