Caribbean Stories

The Day Time Machines Went Kaput

9. Extreme Points

PROFESSOR ROBIN ESCH TOOK THE LECTERN and spoke to us not as the progenitor of a Promethean technology that portended the demise of history but as would a raconteurish grandpa telling stories by the fireplace at a Christmas family reunion. Hot spiced cider and chilled eggnog sprung to mind. After praising junior colleagues Martinelli and Stauffenberg for their steadfast dedication to the project and their fine presentations geared to non-physicists, he jested, earnestly, that their talks would make his sound naïve. As a native New Englander whose devotion to science was surpassed only by a lifelong passion for lobstering in Massachusetts Bay, Esch first talked about the lore and customs that are part and parcel of the art of catching lobsters. He devoted some time to describing the construction and use of lobster pots, the all-important traps he crafts out of wooden slats and wire mesh and nylon netting, pointing out how the cages are dropped to the seabed from the bobbing deck of his cabin skiff, strung securely by rope to a buoy that designates the sunken pots as being his. He rarely takes his catch to the cooking pot, tossing back into the sea most of the hapless crustaceans that fail to find their way out of the trap. “A lot of them do wiggle out”, he assured us. “Clever little critters.” His tale was so delightful I plumb forgot about the time machine. As befits a seasoned academic, he gave a brief historical sketch of lobster pots: they were invented by Ebenezer Thorndike of the town of Swampscott in 1808. Esch was proud of that, for he too is a resident of Swampscott, a wonderful community in the North Shore with a distant shoreline view of the Boston skyline.
    “Lobster pots and chronoportation projects are in a sense similar”, he went on. “They are easy to get into but difficult to exit from successfully. In fact, lobster pots offer much better odds of success. The problem boils down to the quirkiness of quantum physics. It’s more intricate than that of my designs for the pot funnels. You can coax nature to cooperate to some extent, but make no mistake: she calls the shots, not you. Nature is sovereign. We are merely her ephemeral assistants. I am convinced that she is the one making use of us, not the other way around.”
    I thought Esch was going to credit the mathematical bedrock of the universe as the foundation for his philosophical stance. Granted, I can be a tad biased when it comes to extolling math. One’s learning colors one’s views, to avoid the harsher sounding though perhaps more apposite ‘determines’. Yet there’s no question that mathematics governs everything under the sun, Sol included. Mathematica omnia gubernat. At any rate, much to my disappointment, Esch did not mention math.
    “There are two important properties of quantum mechanics that we have not yet discussed that are fundamental to our project. Let’s correct that. The first one is superposition. What this means, for us, is that quantum entities —in particular, subatomic particles— can be in more than one quantum state at one and the same time. Multiple lobsters in the same pot, if you will. This implies that a particle can represent multiple states of information simultaneously. And just how many states can they represent, you might ask. In principle, an infinite number of information states. Storage capacity is not a problem here. Superposition is crucial in the field of quantum computing, which heralds a powerful new way of performing complex computations, though in practice it has yet to get off the ground. It’s turned out to be a recalcitrant problem in physics.”
    Just like string theory: promises galore but a dearth of operational results.
    “The problems they’ve been working on are far from trivial. We, however, have been fortunate in surmounting the impasse by approaching the problem from a different angle, namely, by exploiting posited ‘hidden’ properties inherent to the second item we have not yet discussed: entanglement. This refers to the fact that the quantum states of two particles, or of systems of particles, can, if the particles undergo certain interactions, become interlocked and remain correlated even if the particles are separated by immense distances. Billions of light-years in separation pose no difficulties to entangled particles that behave as a unitary quantum system. Two particles can be located at opposite ends of the universe yet be in immediate quantum-mechanical ‘contact’ with each other, provided they’d become entangled sometime in the past.”
    Amazing. Quantum mechanics tops even the most imaginative sci fi stories in sheer astonishment and counterintuitiveness. Nature deserves a Hugo.
    “But on thinking about this you realize that everything had to be entangled with everything else in the beginning, in the moments after the Big Bang. For the only thing in existence at time zero was a singularity, an infinitesimal point of zero dimensions. Singularities, having no volume capacity, hypersqueeze their contents into zero space. The density of the contents is therefore infinite. That will entangle everything in the subsequent cosmic inflation, when the contents of the singularity explosively emerge. Now, there were no particles at the outset but there was plenty of hyperdense energy, the protostuff that gives rise to particles when things cool down sufficiently. Energy is not fuel or anything like that. Energy is the capacity to do work, the potential to bring about a change of state in a particular system.”
    Sounds like energy is pretty much insubstantial. Bad news for matter.
    “Keep in mind that the quantum breakthrough that has revolutionized every aspect of science and sent shock waves through contemporary philosophy arose due to Planck’s investigations of energy. Photons are particles of electromagnetic energy. Light quanta, Einstein called them. Matter is essentially condensed energy. The key element, the prime mover, is energy, not matter. Matter is basically a form of energy storage. Convenient, certainly — in fact, indispensable, matter being the gateway to our existence. But it is derived, a subsidiary component overshadowed by its mighty precursor. What really matters is energy, not matter.”
    Energy is where the matter is at. Sorry, couldn’t resist.
    “Consequently, it would seem that the entire universe should have remained ‘interconnected’ because of the primordial entanglement caused by the Big Bang’s overwhelming profusion of hyperdense energy. But there is also something called decoherence, which means that quantum entanglements are instantly disentangled when certain events occur, including such things as the entangled particles coming into contact with unentangled particles in their environment, such as those created after the primordial entanglement epoch of the early universe, or being observed in an experiment by intrusive physicists. In such cases, entangled particles decohere and become classical, exhibiting the conventional attributes we consider ‘normal’ for matter and radiation. Decohered particles no longer remain quantum-connected across the vast cosmic landscape. Their spooky unitarity is terminated. The ‘vast distances’, by the way, can also be mere nanometers in extent.”
    Talk about extremes: from billions of light-years to billionths of a meter.
    “But here we run into another problem. Decoherence destroys superposition as well as entanglement. This means that, from the point of view of a macroworld observer, all the superposed quantum states that archived information concerning the entire history of the quantum particle will vanish except one: the classical state the observer is given to observe. We can say that the quantum particle, the original entity that was created and had existed in the quantum realm, has passed into the classical world, turning into a classical particle to the observer. Hence, practically all the information that was stored under superposition will be lost to the observer. This would seem to violate the law of conservation of information.”
    I wasn’t aware there was such a law. That’s absurd. What about irreversible processes? Does entropy not destroy the information that describes the prior state of those systems? Once the perfume evaporates out of the flask, there’s no history of its former liquid state. That information literally evaporated.
    “There was no such law in classical physics in the beginning, although there was widespread agreement that if one could somehow run a mechanical process in reverse —go back in time— one could return to any previous system state. So the information clearly could not have been lost. The laws of physics corroborate that, since they work just as well going forward or backward in time. But then Leonard Susskind and Stephen Hawking got into a decades-long disagreement on whether information was lost when swallowed by a black hole — actually, when the black hole evaporated. That was Hawking’s position. Their controversy was cordial but serious. To Susskind, the «conservation of information» was «the most basic law of nature»*. Hawking eventually conceded that both Susskind and his ally, Gerard ’t Hooft, were correct: information is not irretrievably lost when a black hole, after oodles of eons, evaporates.”
    There must be a hidden lobster somewhere in that tale.
    “Regardless of evaporated information, the law of conservation of quantum information is necessary to maintain mathematical consistency of the entire edifice of physics. For if the laws of physics work splendidly well forward or backward in time, the information necessary to do so must be readily available for processes to operate in either temporal direction. Otherwise, the system would grind to a halt or break apart or become schizophrenic or whatever. But where, one must ask, is the evidence for the availability of this information? Physics is a ‘show me’ discipline, not some speculative yarn. Empirical confirmation is obligatory.”
    Beam him out, Scotty. No Hugo for Esch.
    Roger. Control+Alt+Delete.
    Were it so simple.
    Little dost thou knowest.
    A little grammatical overkill, perhaps?
    Whatever. Look who’s talking.
    “If one could run a quantum system in reverse, one would expect to have the capability of returning to any previous system state, as is believed to be the case in classical mechanics. The question therefore arises: Can reversibility be possible in the ever-shifting quantum milieu that is notoriously awash in uncertainty?”
    Sure. Why not?
    “The outcomes of quantum events are probabilistic, which means that future system states are not ascertainable. This is contrary to the world view of classical mechanics, where present states determine future states. Past states are also fully determined, of course. But the time evolution of quantum systems is deterministic, progressing according to the rules of probability theory. Probabilities are nothing more than numbers that describe states of uncertainty, but the numbers themselves are absolutely certain. They are as rock solid as any other mathematical quantity. And those probabilities, along with the sequence of events that has transpired for every particle, are conserved. At the microscopic level of reality, no information is ever lost. Observers in the macroworld may not be aware of this, but that failing has no effect on the entities populating the quantum domain. Decoherence, we in the project hypothesize, only hides the superposed quantum states of information from the observer, who’s trapped in the pot of the classical macroworld. But in the quantum microworld, every piece of information is meticulously conserved. That is to say, decoherence does not destroy superposed information; it only seems that way to the observer. Decoherence is the process of repackaging complex quantum reality into a simple representation that is compatible with the conditioned ‘reality’ that observers in the macroworld are accustomed to perceive, a ‘reality’ observers can relate to. In effect, what the observer is given to observe —to be precise, what the observer is able to observe from her or his perch in the macroworld— is not that which in reality is. Appearances to the observer are one thing; quantum reality is altogether a different story.”
    Would this then mean that reality is in fact independent of the observer, to wit, objective? Post-modernists would have the mother of all fits, not to mention a good many quantum physicists. And does the foregoing theory imply that Plato’s Allegory of the Cave is correct? Do we really live in a shadow world of flickering copies projected onto our pot’s quantum-friendly, detection simulator screen (all that’s missing is the hi-tek phosphorescence) by a ruling aristocracy of Forms?
    You want fries with that?
    Yes, please.
    “It follows that if information is conserved in meticulous detail ever since the beginning, then the story of history is just lying there waiting to be retrieved.”
    Egads! I have seen the light! The man’s got it! He stands among those of giant shoulders, Chris would surely say, a genius in the classical mold! Well, the quantum mold. Close enough.
    “Note that since history is stored as superposed information on the particles themselves, there is no need of a gargantuan block universe to keep track of past events. Or for projections of the future, for that matter. Minskowski spacetime can be reconstructed by any process as required through the instantaneous mechanisms of superposition and entanglement. The same holds for future system states, which are now liberated from the classical tyranny of predetermination. This is evidently a much simpler theory, one that makes more intuitive sense. There is no need of lugging around a superfluous, incredibly bloated universe. Quantum information makes it easy to jettison all the blocky bulk. We recover a lean, efficient cosmos. Occam’s razor, my friends: the best beacon from hypothesis to proven science.”
    ¡Holy frijole! This guy’s taken the bull by the horns. And he’s running wild through the streets of Pamplona. And the roaring crowd gathered here loves it!
    “So where is the empirical confirmation that would support this theory? My friends, welcome to the Boston University Time Machine Project!”

 Posted: 19 June 2015