Second of two parts (read Part 1)
Max Planck, who shook the world with his discovery of quantum physics, also offered a warning.
“One must be careful,” he said, “when using the word, real.”
It was good advice. As physicists explored the quantum domain, they found that usual ideas about reality did not apply. Reality in the realm of atoms was nothing like the world of rocks and baseballs and planets, where Newton’s laws of motions ruled with rigor. Among atoms, the rules were more like Olympic ice skating judging, with unpredictable scores.
Gradually physicists, engineers and even screenwriters became familiar with quantum weirdness and used it in lasers, computers and movie plots. Quantum reality might be crazy, but it’s our reality, and most scientists, anyway, have become more or less used to it. Nevertheless, Planck’s warning still applies. Perhaps the quantum picture of reality is another illusion, just like Newton’s was. Human insight into nature may not yet have penetrated reality’s ultimate veil.
In other words, maybe reality always dresses itself up in Newtonian or Einsteinian or quantum clothing, and science hasn’t yet seen what reality looks like naked. And that might explain why nature has been able to protect so many of its mysteries from science’s prying eyes — mysteries like the identity of dark matter, the math describing quantum gravity, the mechanism underlying consciousness. And whether humans have free will.
Maybe reality always dresses itself up in Newtonian or Einsteinian or quantum clothing, and science hasn’t yet seen what reality looks like naked.
You could call it Bare World. It’s not an X-rated theme park. It’s what physicist Martin Green calls the ultimate reality.
In Green’s view, the Bare World precedes all ordinary notions of the “Real World” that people perceive and study. That Real World emerges from Bare World.
Observers, matter, time, whatever, all come into existence within Real World; none of those elements of ordinary reality exist within Bare World. Bare World is prephysical. It is something like a mathematical template for what could conceivably exist in Real World. It’s the “foundation for all that might ever be perceived in the universe,” Green writes in a paper posted online last year.
Ordinary reality, then, is like a reflection of the relationships stored in Bare World’s essential structure. As time goes by, more information about those relationships leaks into Real World. Cosmic history, therefore, can be viewed as the “progressively accumulating information” about Bare World. “The advance of time can be identified with both the growth of history and the addition of information about [Bare World] to the observer’s perceived real world,” Green writes.
At the beginning of time, then, the Real World had recorded no information about Bare World at all. But once the cosmic clocked started ticking, Bare World gradually revealed information about itself. Eventually that information accumulated in such a way that the real world supported conscious observers who could wonder about it. But those conscious observers possess only the information about Bare World that has so far been revealed. So humans can never know everything about Bare World. At any point in time, Real World is an “incomplete representation” of Bare World.
Among the conscious observers are scientists who create models of Real World, typically using math, to explain patterns and regularities (laws of nature) that can be used to explain past perceptions and predict future perceptions. But those laws of nature apply to the models of Real World, not Bare World. Bare World is vast; it contains so much information that any number of possible futures will be consistent with the Real World past. Since Bare World contains much more information than Real World can ever accumulate, the laws of Real World do not constrain Bare World from introducing surprises.
“The key message here is that models do not govern reality,” says Green. “They simulate, and thus represent, aspects of reality; but the representations are always unfaithful. This implies that … all physical laws have limited domains of applicability, which we need to discover and accept.”
Human free will is therefore not constrained by the laws of physics — which apply only to Real World, not Bare World.
“I claim that free will is both necessary and natural,” Green asserts. As an observer acquires new information, it is integrated into past information to generate a “present” moment. But the order in which that new information is acquired is determined neither by the present “Real World” moment nor by Bare World.
“Free will,” writes Green, “is a manifestation” of the ability of conscious observers “to influence the order in which previously unknown information about [Bare World] is consistently incorporated into their reality.”
In other words, Bare Reality can be a source for unpredictability in human actions. As physicist Scott Aaronson has articulated, such unpredictability leaves open the possibility that human choices can be freely made. Aaronson speculates that the source of such unpredictability could be quantum particles from the beginning of the universe that affect brain processes today. Green’s proposal suggests that unpredictability comes from outside of ordinary reality, from the prephysical Bare World from which perceived reality emerges. Within that perceived reality, people can make choices.
We actively participate in our perceived reality,” writes Green. “We control our bodies and the world we inhabit sufficiently to collectively investigate, formulate, record, and debate fundamental ideas regarding the world. We refine our models by acting on the world and sensing its response.
“We actively participate in our perceived reality,” writes Green. “We control our bodies and the world we inhabit sufficiently to collectively investigate, formulate, record, and debate fundamental ideas regarding the world. We refine our models by acting on the world and sensing its response.”
And so the future is not strictly determined by the past. Humans can shape it.
“Within bounds — consistent with our limited present knowledge, a prohibition on revising history, and severely limited scope and capacity — we are able to consciously influence our future,” Green declares.
He points out, however, that this sort of free will is not actually free. It comes at a cost. Human choices influence Real World, but Real World must remain consistent with its past and with the influences of all humans. And that implies that each human’s consciousness is not entirely independent of everybody else’s.
“Contrasting with the perception that we can act independently on the world is the obvious requirement for mutual consistency of the perceptions of all observers,” Green writes. “Such consistency can be understood only if consciousness is actually a single, global phenomenon.”
For some people, that realization might lessen free will’s appeal.
But I wouldn’t worry. For one thing, there’s no actual direct evidence for this Bare World idea. It does illustrate, though, the kind of radical revisions in human thought that science might need to make progress on its toughest problems.
And in any case, you don’t need Bare Reality and collective consciousness to have free will. If you think you have free will, you do. Sure, maybe the idea of free will is just in your head. But as the dead Dumbledore told Harry Potter, that doesn’t mean it’s not real.
So if you don’t like Bare World, you can decide for yourself whether you want to believe in it or not. Just be careful when using the word believe.
Follow me on Twitter: @tom_siegfried
