Einstein's Unfinished Revolution -- The Search for What Lies Beyond the Quantum (Penguin Random House 2019).
In Unfinished, the physicist Lee Smolin summarizes the fruit of his lifetime quest to undergird quantum theories with a "complete" physical theory that ties together the continuous world of general relativity with the jerky world of quantum mechanics.
Like two of his scientific beacons, Julian Barbour and Roger Penrose, Smolin is quite the iconoclast, having written incisive science critiques that are accessible to the intelligent lay person and which yet hold value for scientist colleagues. For example, in The Trouble with Physics, Smolin tackles the almost monolithic acceptance of string theory among theoretical physicists -- a skepticism shared by Barbour and Penrose. Other stimulating books are his Time Reborn -- From the Crisis in Physics to the Future of the Universe (Houghton Mifflin Harcourt 2013), Three Roads to Quantum Gravity (Basic Books 2001), and The Life of the Cosmos (Oxford 1997, revised edition 1999).
Unfinished's title refers to the fact that it was Albert Einstein, perhaps more so than Max Planck, who kick-started the quantum revolution with his 1905 paper on the photo-electric effect, which was well explained by taking Planck's notion of energy quantum (indivisible smallest unit) "literally." Twenty-five years later Einstein could not accept that the new quantum theory sufficed as a description of atomic and subatomic events because his philosophy of what is sometimes called "naive realism" was offended. He and Niels Bohr argued for decades about this topic.
Eventually, in the early 1980s, experiments by Alain Aspect established that the principle of locality (no "spooky action at a distance") is false and that what is now called entanglement (spooky action at a distance) holds for certain pairs of particles.
Smolin, I think, does a great service when he takes time to go thru several of the "interpretations" of quantum mechanics. Interpretations, at least at first glance, tend to be independent because one explanation seems as good as another because of the difficulty in testing them. I'm at least somewhat familiar with several of the interpretations he discussed, and yet I learned something new from each discussion. The acuity of his understanding is unmissable.
Smolin, tho sympathetic to Einstein, faces the fact that ultra-naive realism is violated by entanglement. Yet, he cannot abide the Bohr school (or Copenhagen Interpretation) of "anti-realists," and puts himself squarely within the camp of what I call "anti-idealists" -- those who reject John Wheeler's idea that the human brain/mind are looped into the universe in a "spooky" way. Einstein once panned this idealist thinking with the question, "Do you really think the moon isn't there when you aren't looking?"
In fact, Erwin Schrödinger dreamt up his notorious cat thought experiment with just that criticism in mind. According to Bohr, the macro-sized measuring device, in the process of intercepting and amplifying a signal so that a human can detect it, in effect "selects" quantum information that previously had been there simultaneously with other possibly correct information. Well then, said Schrödinger, instead of a tick of a geiger counter presenting the detection, why not let a cat's state of being alive or dead serve as the detection event? That is, if the counter detects an emission from a radioactive isotope within 30 seconds, say, the counter's signal is linked to a poison gas container, which opens if the counter goes off.
But this contraption is concealed by a soundproof box. Human observation does not occur until someone opens the box. Does not the Bohr view imply that the cat was both alive and dead until the box was opened? Remember, according to quantum theory, all that can be said is that the isotope's half-life predicts that a particle could be emitted within the 30 seconds with some probability. By the Heisenberg Uncertainty Principle, the particle has both been emitted and not been emitted -- until it is detected.
Smolin has endeavored to sever the observer from the process, as we used to do in good old Newtonian mechanics. He does so by making time a fundamental reality, with space as a derived delusion(?). The cosmos is made up of Leibnizian-type nads (from Leibniz's monads) which relate to each other in a non-spatial way. Yet Smolin concedes his conceptualization is probably wrong on ground that most new ideas usually are. Plus, I would say he's very persuasive in his devil's advocate role when he questions various anti-idealist notions. For example, on David Bohm's pilot wave idea, Smolin points out that it is disturbing that the wave acts on the particle, but not the converse. That immediately raises suspicion. Where is the reaction one expects with energy conservation?
The fact that, in the quantum regime, energy conservation is a statistical matter does not help much as not even a statistical approach answers that brow-furrower.
Richard Feynman, Smolin says, told him on more than one occasion that his approaches were "not crazy enough" to have much chance of being right. And Smolin agrees that Feynman was right -- about his early work. Well, I cannot hold a candle to either Feynman or Smolin, and yet I venture to add my two-cents' worth here.
The trouble with anti-idealism is that its practitioners prefer an engineering view of physics. I don't mean that as some sort of insult. What I mean is that they want, as much as possible, clean calculations. They want Newton-type simplifications that will serve, and that seem to do the job in virtually all cases. And that's a very good aim. But, that goal isn't all that's there for science.
What is desired by the anti-idealist (who wishes to cut out or down the observer) is linearity. Our routine methods of calculation tend to be linear. In particular, we don't like the notion that the observer becomes so entangled with the machine that one cannot tell where one ends and the other begins. Thus many a scientist wants the physical world "out there" to act independently of the observer.
Yes, of course it is well known that each person's brain has a great deal to do with formation of "subjective reality," but "objective reality" is held to exist as a matter of faith, a faith that would be buttressed if a Smolin-type theory could be tested (which he thinks is possible). Yet I would point out that most of physics is best described by nonlinear differential equations, which in general give us feedback loops, both negative and positive. Mathematical chaos gives examples of positive feedback loops. The asymmetric three-body problem yields mostly chaotic solutions.(We note en passant that some feedback control systems are linear.)
A bit ironically, one might say that linearity is a feature that makes quantum mechanics weird. For example, the superposition of quantum states in wave form requires linearity.
That is, a quantum operator Q, acting on quantum states Ψ and Φ, is characterized by the fact that Q preserves quantum superposition [See Fashion, Faith and Fantasy in the New Physics of the Universe by Roger Penrose (Princeton 2016), page 100.]
The equation
Q(wΨ + zΦ) = wQ(Ψ) + zQ(Φ),
fulfills one mathematical definition of "linearity."
But of course this equation does not resolve the Schrodinger cat puzzle, tho, depending on your point of view, it seems to imply it. The possibility of nonlinearity is introduced only on detection.
Einstein's general theory of relativity has space, time and gravity all interacting in a nonlinear way, tho of course linear approximations are available. Even his earlier special theory had problems of nonlinearity. Whether an observer gets electrocuted or not may depend on his angular velocity with respect to an electromagnetic field. Then there is the case of the oft-misunderstood twins paradox.
My point is: why should the situation that obtains between the observer and the physical world be miraculously nonlinear? It would seem that some sort of idealist solution is far more probable. Yes, you say, but decoherence saves Schrödinger's cat from having a history that is partly due to my or your mind. Yet why should there be a law that says alternate "real" histories are impossible? After all,
Does anyone really know what time is?
Like two of his scientific beacons, Julian Barbour and Roger Penrose, Smolin is quite the iconoclast, having written incisive science critiques that are accessible to the intelligent lay person and which yet hold value for scientist colleagues. For example, in The Trouble with Physics, Smolin tackles the almost monolithic acceptance of string theory among theoretical physicists -- a skepticism shared by Barbour and Penrose. Other stimulating books are his Time Reborn -- From the Crisis in Physics to the Future of the Universe (Houghton Mifflin Harcourt 2013), Three Roads to Quantum Gravity (Basic Books 2001), and The Life of the Cosmos (Oxford 1997, revised edition 1999).
Unfinished's title refers to the fact that it was Albert Einstein, perhaps more so than Max Planck, who kick-started the quantum revolution with his 1905 paper on the photo-electric effect, which was well explained by taking Planck's notion of energy quantum (indivisible smallest unit) "literally." Twenty-five years later Einstein could not accept that the new quantum theory sufficed as a description of atomic and subatomic events because his philosophy of what is sometimes called "naive realism" was offended. He and Niels Bohr argued for decades about this topic.
Eventually, in the early 1980s, experiments by Alain Aspect established that the principle of locality (no "spooky action at a distance") is false and that what is now called entanglement (spooky action at a distance) holds for certain pairs of particles.
Smolin, I think, does a great service when he takes time to go thru several of the "interpretations" of quantum mechanics. Interpretations, at least at first glance, tend to be independent because one explanation seems as good as another because of the difficulty in testing them. I'm at least somewhat familiar with several of the interpretations he discussed, and yet I learned something new from each discussion. The acuity of his understanding is unmissable.
Smolin, tho sympathetic to Einstein, faces the fact that ultra-naive realism is violated by entanglement. Yet, he cannot abide the Bohr school (or Copenhagen Interpretation) of "anti-realists," and puts himself squarely within the camp of what I call "anti-idealists" -- those who reject John Wheeler's idea that the human brain/mind are looped into the universe in a "spooky" way. Einstein once panned this idealist thinking with the question, "Do you really think the moon isn't there when you aren't looking?"
In fact, Erwin Schrödinger dreamt up his notorious cat thought experiment with just that criticism in mind. According to Bohr, the macro-sized measuring device, in the process of intercepting and amplifying a signal so that a human can detect it, in effect "selects" quantum information that previously had been there simultaneously with other possibly correct information. Well then, said Schrödinger, instead of a tick of a geiger counter presenting the detection, why not let a cat's state of being alive or dead serve as the detection event? That is, if the counter detects an emission from a radioactive isotope within 30 seconds, say, the counter's signal is linked to a poison gas container, which opens if the counter goes off.
But this contraption is concealed by a soundproof box. Human observation does not occur until someone opens the box. Does not the Bohr view imply that the cat was both alive and dead until the box was opened? Remember, according to quantum theory, all that can be said is that the isotope's half-life predicts that a particle could be emitted within the 30 seconds with some probability. By the Heisenberg Uncertainty Principle, the particle has both been emitted and not been emitted -- until it is detected.
Smolin has endeavored to sever the observer from the process, as we used to do in good old Newtonian mechanics. He does so by making time a fundamental reality, with space as a derived delusion(?). The cosmos is made up of Leibnizian-type nads (from Leibniz's monads) which relate to each other in a non-spatial way. Yet Smolin concedes his conceptualization is probably wrong on ground that most new ideas usually are. Plus, I would say he's very persuasive in his devil's advocate role when he questions various anti-idealist notions. For example, on David Bohm's pilot wave idea, Smolin points out that it is disturbing that the wave acts on the particle, but not the converse. That immediately raises suspicion. Where is the reaction one expects with energy conservation?
The fact that, in the quantum regime, energy conservation is a statistical matter does not help much as not even a statistical approach answers that brow-furrower.
Richard Feynman, Smolin says, told him on more than one occasion that his approaches were "not crazy enough" to have much chance of being right. And Smolin agrees that Feynman was right -- about his early work. Well, I cannot hold a candle to either Feynman or Smolin, and yet I venture to add my two-cents' worth here.
The trouble with anti-idealism is that its practitioners prefer an engineering view of physics. I don't mean that as some sort of insult. What I mean is that they want, as much as possible, clean calculations. They want Newton-type simplifications that will serve, and that seem to do the job in virtually all cases. And that's a very good aim. But, that goal isn't all that's there for science.
What is desired by the anti-idealist (who wishes to cut out or down the observer) is linearity. Our routine methods of calculation tend to be linear. In particular, we don't like the notion that the observer becomes so entangled with the machine that one cannot tell where one ends and the other begins. Thus many a scientist wants the physical world "out there" to act independently of the observer.
Yes, of course it is well known that each person's brain has a great deal to do with formation of "subjective reality," but "objective reality" is held to exist as a matter of faith, a faith that would be buttressed if a Smolin-type theory could be tested (which he thinks is possible). Yet I would point out that most of physics is best described by nonlinear differential equations, which in general give us feedback loops, both negative and positive. Mathematical chaos gives examples of positive feedback loops. The asymmetric three-body problem yields mostly chaotic solutions.(We note en passant that some feedback control systems are linear.)
A bit ironically, one might say that linearity is a feature that makes quantum mechanics weird. For example, the superposition of quantum states in wave form requires linearity.
That is, a quantum operator Q, acting on quantum states Ψ and Φ, is characterized by the fact that Q preserves quantum superposition [See Fashion, Faith and Fantasy in the New Physics of the Universe by Roger Penrose (Princeton 2016), page 100.]
The equation
Q(wΨ + zΦ) = wQ(Ψ) + zQ(Φ),
fulfills one mathematical definition of "linearity."
But of course this equation does not resolve the Schrodinger cat puzzle, tho, depending on your point of view, it seems to imply it. The possibility of nonlinearity is introduced only on detection.
Einstein's general theory of relativity has space, time and gravity all interacting in a nonlinear way, tho of course linear approximations are available. Even his earlier special theory had problems of nonlinearity. Whether an observer gets electrocuted or not may depend on his angular velocity with respect to an electromagnetic field. Then there is the case of the oft-misunderstood twins paradox.
My point is: why should the situation that obtains between the observer and the physical world be miraculously nonlinear? It would seem that some sort of idealist solution is far more probable. Yes, you say, but decoherence saves Schrödinger's cat from having a history that is partly due to my or your mind. Yet why should there be a law that says alternate "real" histories are impossible? After all,
Does anyone really know what time is?
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