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Beyond the Quantum: A Quest for the Origin and Hidden Meaning of Quantum Mechanics
Based on decades of research, this book offers a panoramic rethink of quantum physics, with potentially revolutionary implications for cosmology, quantum gravity, and quantum technology.
Properly understood, 'pilot-wave theory' provides a deeper foundation for quantum mechanics, while also going beyond it. First proposed in the 1920s by French aristocrat and physicist Louis de Broglie, and revived in the 1950s by American physicist David Bohm, the theory posits hidden particle motions we cannot currently see or control. The theory is usually regarded as merely an alternative account of the same physics we already know. In fact, pilot-wave theory implies a wealth of new and radical physics beyond the reach of quantum mechanics.
Pilot-wave theory tells us that quantum physics is a special case of something broader and deeper. In more general 'nonequilibrium' conditions, Einstein's relativity and Heisenberg's uncertainty break down. Superluminal signalling becomes possible, and quantum particles can be clearly seen and controlled. This new physics could have left traces in the early universe, and it might be visible today in radiation from exploding primordial black holes. Harnessing this new physics would have transformative technological implications, in particular for communication, cryptography, and computing.
Drawing intriguing parallels between the present era of quantum physics and past episodes of scientific confusion, this book tells the story of how pilot-wave theory was discovered and abandoned, revived and reconstructed, and how today it can pave the way to a new and radical physics beyond the quantum.
Properly understood, 'pilot-wave theory' provides a deeper foundation for quantum mechanics, while also going beyond it. First proposed in the 1920s by French aristocrat and physicist Louis de Broglie, and revived in the 1950s by American physicist David Bohm, the theory posits hidden particle motions we cannot currently see or control. The theory is usually regarded as merely an alternative account of the same physics we already know. In fact, pilot-wave theory implies a wealth of new and radical physics beyond the reach of quantum mechanics.
Pilot-wave theory tells us that quantum physics is a special case of something broader and deeper. In more general 'nonequilibrium' conditions, Einstein's relativity and Heisenberg's uncertainty break down. Superluminal signalling becomes possible, and quantum particles can be clearly seen and controlled. This new physics could have left traces in the early universe, and it might be visible today in radiation from exploding primordial black holes. Harnessing this new physics would have transformative technological implications, in particular for communication, cryptography, and computing.
Drawing intriguing parallels between the present era of quantum physics and past episodes of scientific confusion, this book tells the story of how pilot-wave theory was discovered and abandoned, revived and reconstructed, and how today it can pave the way to a new and radical physics beyond the quantum.
- GenresPhysics
336 pages, Hardcover
Published January 3, 2026
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March 21, 2026
I’ll start by saying there is a lot here that I don’t understand. That’s not Valentini’s fault. I’m not a physicist, but I’m certain a lot of physicists would find much here that they don’t understand either. This is “beyond” quantum theory after all, and physicists, for the most part, admit to not really understanding quantum theory.
Disclaimers aside, then . . .
I’ll start with the problem Valentini is attempting to solve. There are good reasons to be dissatisfied with quantum theory, as it now stands. It describes a universe whose pervading characteristic at the micro-level, uncertainty, vanishes at the macro-level. The transition between the two, as Valentini argues, is itself uncertain. Where exactly does uncertainty vanish or transition to a macro-level of apparent determinism? Uncertainty itself is considered a problem for thorough physical determinists.
The measurement problem goes hand in hand with uncertainty. Values for the attributes of microparticles can only be specified as probabilities until those values are measured. And then the values pop into place. Until the measurement, the values are intrinsically probabilistic. The measurement, by some accounts necessarily involving a human observer, appears to change reality, to change an intrinsically probabilistic value to a fixed one. The paradoxical nature of the role of measurement is dramatized by the Schrödinger’s Cat thought experiment.
Entanglement. Two particles can share a connection that seems to defy our understanding of causality and the limitation of interactions between particles to the speed of light. For example, electrons produced in subatomic interactions may be entangled in such a way that a measurement of an attribute of one electron (e.g., its spin) determines the outcome of the measurement of the second electron regardless of the distance between them or the time lapse between the measurements. It’s as if the one measurement determines the other instantaneously and over arbitrary distance, what Einstein objected to as “spooky action at a distance.”
What some physicists deride as “just philosophical” is the problem of quantum theory’s “interpretability.” I.e., what does it actually mean, as a purported description of reality? What is real according to the theory? Any attempt to render quantum theory as a theory about “particles” or “waves” ends in caveats and misconceptions. The physicist’s advice to “shut up and calculate” is either avoidance of the question entirely or a claim that the mathematics that allows us to calculate actually does, contrary to intuition, count as a “description” of what is real. A Pythagorean fever-dream.
Valentini proposes to solve some of these problems, or at least to chart a direction to do so.
Here is the fundamental hypothesis put forward in this book:
Current quantum theory describes a universe that is in a particular state, termed “quantum equilibrium.” That state is distinguished by quantum uncertainty, the Born formula (expressing particle attributes as probabilities), and what Valentini generally describes as a “quantum fog” that prevents us from seeing a universe described by a more general theory called “pilot wave theory.” Pilot wave theory posits a deterministic universe where all events (and “things”) are connected in a multidimenstional web, and where those connections afford instantaneous interactions.
This “quantum fog” is a consequence of the violent interactions of the very early universe producing an equilibrium state in which particle positions and behaviors are no longer determinate. Were we able to access particles unaffected by that violent history, we would see instead particles whose behavior is well described and determinable, i.e., to which uncertainty and the Born formula do not apply.
Quantum theory (as well as relativity theory) then describe this special state of “quantum fog” or “quantum equilibrium” with pilot wave theory encompassing those special states within a more general theory of the physical universe.
Pilot wave theory is not altogether a new theory. Valentini credits Louis de Broglie with proposing pilot wave theory in 1927, and David Bohm with having expanded and elaborated it in the 1950s. Pilot wave theory does go “beyond” quantum theory, not only in proposing to encompass quantum reality as a special state, but in redrawing something so basic as Newton’s understanding of motion.
According to Newton, any object in motion continues in motion along a straight line unless affected by some disturbing force. According to pilot wave theory, all objects in motion are carried along in their motion by a “pilot wave,” a hypothesized wave on which particles (or fields) ride and which determines the direction and other aspects of their motion.
Pilot wave theory is a “hidden variables” theory — one in which quantum events, contrary to their apparent probabilistic treatment under the standard interpretation of quantum theory, are determined by variables we do not observe or control. The pilot wave itself is unobserved but determining the behavior of particles in motion.
Valentini provides a redescription of the classic double slit experiment in which the motion of particles, carried by the pilot wave, are deterministic and traceable to the level of single particles, contrary to the standard interpretation in which their paths are undetermined and characterized by a probability function. Valentini’s redescription doesn’t alter the end result, the pattern of target impacts in the double slit experiment, but only the account of the paths that particles have taken to reach the target. What remains uncertain, under the redescription, are the initial positions of the particles, due to the fog of quantum equilibrium. Were we to know those positions, we could make accurate predictions of the particles' paths and points of impact.
We should be clear that pilot waves are hypothesized, not observed, although the pilot wave hypothesis can be spelled out in mathematical terms, with predictions identical to quantum theory, given the special state of “quantum equilibrium.” Pilot wave theory, however, also supposes, in the absence of that special state, a clearing of the “fog” that prevents us from escaping the uncertainty and the probabilistic nature of particles and fields under quantum theory, and even the speed limit imposed upon signals and interactions imposed by relativity theory.
That’s a lot. And, to be honest, it’s a lot of supposing.
So what would be evidence of pilot wave theory? What kinds of observations or experiments would demonstrate its validity?
Since, according to the theory, we in fact live in a universe in quantum equilibrium, the predictions yielded by pilot wave theory are identical to those yielded by quantum theory. There is no way to differentiate between the two. And the limitations of uncertainty, etc. still hold under pilot wave theory.
Unless we could gain access to particles that were not in quantum equilibrium. And according to pilot wave theory, that is in principle possible. Since quantum equilibrium is proposed as a state to which the universe evolved in its early history, if we could find relic material from the universe’s history prior to that state, we could test the theory with that material. Pilot wave theory, for experiments or observations of particles not in quantum equilibrium, would provide predictions different from those of quantum theory. Specifically, it would yield deterministic predictions at the level of single particles, rather than the probabilistic predictions yielded by quantum theory that can only be validated on a statistical level.
Valentini proposes several sources for non-equilibrium particles, either as relics unaffected by the interactions that have produced the quantum equilibrium state, i.e., primordial particles that have in one way or another been insulated against those interactions, or as particles returned to that more primordial state in some way.
For the former, the relic particles, he proposes that dark matter may fit the bill. Of course, we don’t know what dark matter is, whether it is the kind of relic matter Valentini hopes it to be, or some other matter just as affected by quantum equilibrium as ordinary matter. But, as he says, it’s worth finding out, since an investigation of dark matter is in the queue anyway.
For the latter possibility, matter returned to a non-equilibrium primordial state, he proposes matter emitted by the evaporation or explosions of black holes, in accordance with Hawking’s theory of black hole evolution. That evolution takes a long time in the case of large black holes, such as stellar mass black holes, much less supermassive black holes like those at the centers of galaxies. But there may be mini black holes, perhaps formed in the early universe, whose evolutionary path has reached an end. We may be able to detect the final stages of those black holes’ lifetimes via gamma ray emissions.
Although the sources of those particles may be at great distances from us, emissions from them could be studied via experiments like the double-slit experiment. Pilot wave theory would yield different predictions for those non-equilibrium emissions than quantum theory, and it would be possible to validate the one over the other.
Valentini also speculates, in a chapter towards the end of the book, about various technologies that could be built using non-equilibrium matter, if pilot wave theory is true. Those technologies could include instantaneous signaling, “subquantum computing", and more. Valentini even speculates that alien intelligences might use non-equilibrium material and instantaneous signaling as communications technologies, and that, if so, their presence might be detectable by monitoring for those signals.
There’s a lot more here that I haven’t, and mostly can’t, explain. In particular, I haven’t explained in any detail how Valentini supposes that the current state of quantum equilibrium, which “fogs” our observations of quantum level particles and events, really came about in the very early universe. And I haven’t explained what a “pilot wave” really is or how it functions.
Partly I think that is because Valentini is writing this book for something like a “general” audience — no math, no formulas, just conceptual description. Even so, I don’t know how “general” that audience could be. Valentini is not a “science writer,” he’s a scientist, and his thoughts and delivery are in that mode.
Pilot wave theory is a supposition. That much we should be clear about. It is not motivated by experimental failures of quantum theory. Valentini is an energetic proponent of going farther than quantum theory, to reach a theory that is more understandable, more explicit in its interpretability as a description of reality.
And he’s certainly right that quantum theory itself falls short. Pilot wave theory is speculative, in keeping with the brand of mathematical rationalism that has given us some great discoveries. Black holes, antimatter, and other discoveries originated from mathematical reasoning. On the other hand, so did supersymmetry, which has not found the same great success (so far).
Speculation of this sort is a driver of science, so it’s to be fully applauded, at least in so far as I understand it. That’s my bottom line on the book.
Separately, though, I can’t let Valentini’s Epilogue go without comment. I was thoroughly engaged in and energized by the book up until the Epilogue. Valentini takes a step back there to give voice to his insistence that something must overcome the limitations of knowledge that prevail under quantum theory. He doesn’t just not like mystery, it seems a desecration to him. That human understanding might be limited seems unacceptable, so something like pilot wave theory must be true.
That’s not a scientific position. And if we call it a “philosophical” position, it should meet the standards of philosophical argument. I don’t think it does, as presented by Valentini. In the Epilogue, he excoriates Kant’s theory of knowledge, and its influence, as he sees it, on Heisenberg and other core proponents of quantum theory. His reading of Kant and subsequent work presents a subjectivist turn away from objective knowledge. That may well be a reading of Kant that influenced Heisenberg, but it doesn’t square with my own reading of Kant, or modern philosophy of science. In fact, by my reading of Kant, Kant’s very project was explicitly to demonstrate how objective knowledge is possible.
Valentini’s account, as brief as it is (and so maybe he could spell out a fuller argument) confuses some basics of Kantian and subsequent thought, specifically supposing that Kant’s “categories” are equivalent to Newton’s Laws and supposing that Kant’s limitations on knowledge of “things-in-themselves” applies to objective reality. In opposition to any limitations on scientific knowledge, Valentini resorts to a polemic based on appeals to an unargued-for naive realism.
I know this strays into a very big and nuanced discussion, and this is not, despite the tone of Valentini’s Epilogue, a book about Kant or philosophy of science. Suffice to say, I was more impressed by Valentini’s speculative proposal of pilot wave theory as a fuller account of physical reality than by his attack on contemporary theories of scientific knowledge. The book’s Epilogue wandered into unnecessary territory.
Disclaimers aside, then . . .
I’ll start with the problem Valentini is attempting to solve. There are good reasons to be dissatisfied with quantum theory, as it now stands. It describes a universe whose pervading characteristic at the micro-level, uncertainty, vanishes at the macro-level. The transition between the two, as Valentini argues, is itself uncertain. Where exactly does uncertainty vanish or transition to a macro-level of apparent determinism? Uncertainty itself is considered a problem for thorough physical determinists.
The measurement problem goes hand in hand with uncertainty. Values for the attributes of microparticles can only be specified as probabilities until those values are measured. And then the values pop into place. Until the measurement, the values are intrinsically probabilistic. The measurement, by some accounts necessarily involving a human observer, appears to change reality, to change an intrinsically probabilistic value to a fixed one. The paradoxical nature of the role of measurement is dramatized by the Schrödinger’s Cat thought experiment.
Entanglement. Two particles can share a connection that seems to defy our understanding of causality and the limitation of interactions between particles to the speed of light. For example, electrons produced in subatomic interactions may be entangled in such a way that a measurement of an attribute of one electron (e.g., its spin) determines the outcome of the measurement of the second electron regardless of the distance between them or the time lapse between the measurements. It’s as if the one measurement determines the other instantaneously and over arbitrary distance, what Einstein objected to as “spooky action at a distance.”
What some physicists deride as “just philosophical” is the problem of quantum theory’s “interpretability.” I.e., what does it actually mean, as a purported description of reality? What is real according to the theory? Any attempt to render quantum theory as a theory about “particles” or “waves” ends in caveats and misconceptions. The physicist’s advice to “shut up and calculate” is either avoidance of the question entirely or a claim that the mathematics that allows us to calculate actually does, contrary to intuition, count as a “description” of what is real. A Pythagorean fever-dream.
Valentini proposes to solve some of these problems, or at least to chart a direction to do so.
Here is the fundamental hypothesis put forward in this book:
Current quantum theory describes a universe that is in a particular state, termed “quantum equilibrium.” That state is distinguished by quantum uncertainty, the Born formula (expressing particle attributes as probabilities), and what Valentini generally describes as a “quantum fog” that prevents us from seeing a universe described by a more general theory called “pilot wave theory.” Pilot wave theory posits a deterministic universe where all events (and “things”) are connected in a multidimenstional web, and where those connections afford instantaneous interactions.
This “quantum fog” is a consequence of the violent interactions of the very early universe producing an equilibrium state in which particle positions and behaviors are no longer determinate. Were we able to access particles unaffected by that violent history, we would see instead particles whose behavior is well described and determinable, i.e., to which uncertainty and the Born formula do not apply.
Quantum theory (as well as relativity theory) then describe this special state of “quantum fog” or “quantum equilibrium” with pilot wave theory encompassing those special states within a more general theory of the physical universe.
Pilot wave theory is not altogether a new theory. Valentini credits Louis de Broglie with proposing pilot wave theory in 1927, and David Bohm with having expanded and elaborated it in the 1950s. Pilot wave theory does go “beyond” quantum theory, not only in proposing to encompass quantum reality as a special state, but in redrawing something so basic as Newton’s understanding of motion.
According to Newton, any object in motion continues in motion along a straight line unless affected by some disturbing force. According to pilot wave theory, all objects in motion are carried along in their motion by a “pilot wave,” a hypothesized wave on which particles (or fields) ride and which determines the direction and other aspects of their motion.
Pilot wave theory is a “hidden variables” theory — one in which quantum events, contrary to their apparent probabilistic treatment under the standard interpretation of quantum theory, are determined by variables we do not observe or control. The pilot wave itself is unobserved but determining the behavior of particles in motion.
Valentini provides a redescription of the classic double slit experiment in which the motion of particles, carried by the pilot wave, are deterministic and traceable to the level of single particles, contrary to the standard interpretation in which their paths are undetermined and characterized by a probability function. Valentini’s redescription doesn’t alter the end result, the pattern of target impacts in the double slit experiment, but only the account of the paths that particles have taken to reach the target. What remains uncertain, under the redescription, are the initial positions of the particles, due to the fog of quantum equilibrium. Were we to know those positions, we could make accurate predictions of the particles' paths and points of impact.
We should be clear that pilot waves are hypothesized, not observed, although the pilot wave hypothesis can be spelled out in mathematical terms, with predictions identical to quantum theory, given the special state of “quantum equilibrium.” Pilot wave theory, however, also supposes, in the absence of that special state, a clearing of the “fog” that prevents us from escaping the uncertainty and the probabilistic nature of particles and fields under quantum theory, and even the speed limit imposed upon signals and interactions imposed by relativity theory.
That’s a lot. And, to be honest, it’s a lot of supposing.
So what would be evidence of pilot wave theory? What kinds of observations or experiments would demonstrate its validity?
Since, according to the theory, we in fact live in a universe in quantum equilibrium, the predictions yielded by pilot wave theory are identical to those yielded by quantum theory. There is no way to differentiate between the two. And the limitations of uncertainty, etc. still hold under pilot wave theory.
Unless we could gain access to particles that were not in quantum equilibrium. And according to pilot wave theory, that is in principle possible. Since quantum equilibrium is proposed as a state to which the universe evolved in its early history, if we could find relic material from the universe’s history prior to that state, we could test the theory with that material. Pilot wave theory, for experiments or observations of particles not in quantum equilibrium, would provide predictions different from those of quantum theory. Specifically, it would yield deterministic predictions at the level of single particles, rather than the probabilistic predictions yielded by quantum theory that can only be validated on a statistical level.
Valentini proposes several sources for non-equilibrium particles, either as relics unaffected by the interactions that have produced the quantum equilibrium state, i.e., primordial particles that have in one way or another been insulated against those interactions, or as particles returned to that more primordial state in some way.
For the former, the relic particles, he proposes that dark matter may fit the bill. Of course, we don’t know what dark matter is, whether it is the kind of relic matter Valentini hopes it to be, or some other matter just as affected by quantum equilibrium as ordinary matter. But, as he says, it’s worth finding out, since an investigation of dark matter is in the queue anyway.
For the latter possibility, matter returned to a non-equilibrium primordial state, he proposes matter emitted by the evaporation or explosions of black holes, in accordance with Hawking’s theory of black hole evolution. That evolution takes a long time in the case of large black holes, such as stellar mass black holes, much less supermassive black holes like those at the centers of galaxies. But there may be mini black holes, perhaps formed in the early universe, whose evolutionary path has reached an end. We may be able to detect the final stages of those black holes’ lifetimes via gamma ray emissions.
Although the sources of those particles may be at great distances from us, emissions from them could be studied via experiments like the double-slit experiment. Pilot wave theory would yield different predictions for those non-equilibrium emissions than quantum theory, and it would be possible to validate the one over the other.
Valentini also speculates, in a chapter towards the end of the book, about various technologies that could be built using non-equilibrium matter, if pilot wave theory is true. Those technologies could include instantaneous signaling, “subquantum computing", and more. Valentini even speculates that alien intelligences might use non-equilibrium material and instantaneous signaling as communications technologies, and that, if so, their presence might be detectable by monitoring for those signals.
There’s a lot more here that I haven’t, and mostly can’t, explain. In particular, I haven’t explained in any detail how Valentini supposes that the current state of quantum equilibrium, which “fogs” our observations of quantum level particles and events, really came about in the very early universe. And I haven’t explained what a “pilot wave” really is or how it functions.
Partly I think that is because Valentini is writing this book for something like a “general” audience — no math, no formulas, just conceptual description. Even so, I don’t know how “general” that audience could be. Valentini is not a “science writer,” he’s a scientist, and his thoughts and delivery are in that mode.
Pilot wave theory is a supposition. That much we should be clear about. It is not motivated by experimental failures of quantum theory. Valentini is an energetic proponent of going farther than quantum theory, to reach a theory that is more understandable, more explicit in its interpretability as a description of reality.
And he’s certainly right that quantum theory itself falls short. Pilot wave theory is speculative, in keeping with the brand of mathematical rationalism that has given us some great discoveries. Black holes, antimatter, and other discoveries originated from mathematical reasoning. On the other hand, so did supersymmetry, which has not found the same great success (so far).
Speculation of this sort is a driver of science, so it’s to be fully applauded, at least in so far as I understand it. That’s my bottom line on the book.
Separately, though, I can’t let Valentini’s Epilogue go without comment. I was thoroughly engaged in and energized by the book up until the Epilogue. Valentini takes a step back there to give voice to his insistence that something must overcome the limitations of knowledge that prevail under quantum theory. He doesn’t just not like mystery, it seems a desecration to him. That human understanding might be limited seems unacceptable, so something like pilot wave theory must be true.
That’s not a scientific position. And if we call it a “philosophical” position, it should meet the standards of philosophical argument. I don’t think it does, as presented by Valentini. In the Epilogue, he excoriates Kant’s theory of knowledge, and its influence, as he sees it, on Heisenberg and other core proponents of quantum theory. His reading of Kant and subsequent work presents a subjectivist turn away from objective knowledge. That may well be a reading of Kant that influenced Heisenberg, but it doesn’t square with my own reading of Kant, or modern philosophy of science. In fact, by my reading of Kant, Kant’s very project was explicitly to demonstrate how objective knowledge is possible.
Valentini’s account, as brief as it is (and so maybe he could spell out a fuller argument) confuses some basics of Kantian and subsequent thought, specifically supposing that Kant’s “categories” are equivalent to Newton’s Laws and supposing that Kant’s limitations on knowledge of “things-in-themselves” applies to objective reality. In opposition to any limitations on scientific knowledge, Valentini resorts to a polemic based on appeals to an unargued-for naive realism.
I know this strays into a very big and nuanced discussion, and this is not, despite the tone of Valentini’s Epilogue, a book about Kant or philosophy of science. Suffice to say, I was more impressed by Valentini’s speculative proposal of pilot wave theory as a fuller account of physical reality than by his attack on contemporary theories of scientific knowledge. The book’s Epilogue wandered into unnecessary territory.
May 20, 2026
An interesting read after reading the holographic universe.
Quite informative
Quite informative
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