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Aspect, A., Grangier, P., & Roger, G. (1982). Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell’s Inequalities. Physical Review Letters, 49(2), 91–94.

Audretsch, J. (2004). Entangled World: The fascination of quantum information and computation. Wiley.

Baggot, J. (2013). Farewell to Reality: How fairytale physics betrays the search for scientific truth. Constable.

Barbour, J. (1999). The End of Time: The next revolution in physics. Oxford University Press.

Barrow, J. D. (2007). New theories of everything. Oxford University Press.

Bekenstein, J. D. (2003). Information in the Holographic Universe. Scientific American, 289(2), 58–65.

Bojowald, M. (2008). Follow the Bouncing Universe. Scientific American, October, 28–33.

Bolles, E. B. (1999). Galileo’s Commandment: 2,500 years of great science writing. W. H. Freeman.

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Cox, B., & Forshaw, J. (2011). The Quantum Universe: Everything That Can Happen Does Happen. Allen Lane.

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Hoffman, D. (2020). The Case Against Reality: How Evolution Hid The Truth From Our Eyes. Penguin Books.

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Laughlin, R. B. (2005). A Different Universe: Reinventing physics from the bottom down. Basic Books.

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The following questions are addressed in this chapter. They are better discussed in a group to allow a variety of opinions to emerge. The relevant section link is given after each question:

1. Why is light still a mystery to science? (QR3.1.1)

2. Is light made of waves, particles, or both? (QR3.1.2)

3. In Young’s experiment, does a photon go through both slits or just one? Give reasons. (QR3.1.3)

4. What is the main issue that Bohr’s Copenhagen dualism faces? (QR3.1.4)

5. What is meant by a “Pinocchio” theory? Is quantum mechanics one in current physics? (QR3.1.5)

6. How do scientists know that light is a wave? (QR3.2.1)

7. What is meant by a three-dimensional “Flatland”? Could our world be so? (QR3.2.2)

8. According to current physics, is a photon a perpetual-motion machine? (QR3.2.3) 

9. Is the speed of light better described as the speed of space? (QR3.2.4)

10. What do X-rays, visible light, and radio waves have in common? (QR3.3.1)

11. Why does energy come in Planck units? Why does light come in photon units? (QR3.3.2)

12. Why does Planck’s constant also define the size of our space? (QR3.3.3)

13. If a quantum wave is a processing wave, how does it spread? (QR3.4.2)

14. According to quantum theory, does a photon have a quantum wave or is it one? (QR3.4.3)

15. Will hidden physical causes ever explain why photons hit a screen at random points? (QR3.5.1)

16. How can a quantum wave of any size collapse instantly to a point? (QR3.5.2)

17. Why does the power of a photon wave predict its probability of existing at a point? (QR3.5.3)

18. Can a particle always find the shortest path to any destination? (QR3.6.2)

19. How can a photon of light always find the shortest path to any destination? (QR3.6.3)

20. Why is the measured direction of quantum spin always random? (QR3.7.1)

21. Why doesn’t a filter that blocks horizontal polarized light block vertical polarized light? (QR3.7.2)

22. Why doesn’t a filter that stops most of a polarized light ray weaken those that pass it? (QR3.7.3)

23. How can quantum states superpose in physically incompatible ways? (QR3.8.1)

24. In quantum theory, observation creates physical reality, so is life just a dream? (QR3.8.2)

25. Do delayed choice experiments prove that the future can affect the past? (QR3.8.3)

26. Can light detect an object on a path it didn’t travel? Is this physically possible? (QR3.8.4)

27. How do entangled photons affect each other faster than light? (QR3.8.5)

28. Is our world distinguishable from a hologram? Why does a virtual reality require this? (QR3.8.6)

29. If there no evidence for the multiverse, why do many physicists accept it? (QR3.9.1)

30. Why is the observer necessary, even in physics? (QR3.9.2)

31. What is the quantum paradox? How has physics handled it? (QR3.9.3)

32. Does quantum theory deny realism, that there is a real world out there? (QR3.9.4)

33. Give examples of how evolution has opposed science. (QR3.9.5)

34. Does quantum theory support Plato’s allegory? What then is “the cave”? (QR3.9.6)

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Plato’s cave is an allegory told over two thousand years ago (Figure 3.27). It describes human beings as like prisoners in a cave, chained with their backs to the entrance, through which sunlight streams. They can’t see the sunlight, only the shadows it casts on the cave wall, so they take them as real, and act accordingly.

Today, we see ourselves standing in the sunlight of science before the dark cave of quantum mystery, but according to Plato, it is the other way around. We are still in the cave of materialism calling the shadows we see real. Quantum theory agrees, as it implies that we observe images generated by the quantum sunlight on the wall of space.  

Quantum theory reinvents Plato’s vision in scientific terms. The big bang of physics was brighter than any star but the sun is a good analogy. If Plato’s cave is our universe, its walls are our space, and the chains that bind were made by evolution. This is no contrived puppet-show, as our shadows add to the show, and the prisoners aren’t just us, but everything that observes. Plato’s cave is then an allegory of what quantum theory is telling us today. 

Why then don’t we turn from the shadows, to see their cause? Einstein tried but the quantum sunlight baffled him, so he concluded that it was nothing. Bohr tried too, but his impenetrable Copenhagen suit showed only reflections, so he concluded it was unreal. Physicists then quarantined the quantum light behind a wall of equations that only they could read, to use it without looking at it. The first rule of the quantum club became that it is about nothing, so there is no quantum light say those who use it to predict our shadow future. Yet some still tried to envision it.

The physicist Wheeler called quantum reality the great smoky dragon (Wheeler, 1983), as it was both powerful and mythical, but if this dragon is real, the world we see is its smoke (Figure 3.28). The quantum world isn’t a shadow world beyond physical reality, but the real world whose shadows are the physical world we see.

Table 3.3 compares quantum realism and physical realism for light, but if our universe began as light, how did matter arise? The next chapter addresses this question.

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Quantum theory describes an immaterial world, of which Bohr said we must not speak, but some physicists still wonder what the universe is like when it isn’t being observed:

“Little has been said about the character of the unmeasured state. Since most of reality most of the time dwells in this unmeasured condition …the lack of such a description leaves the majority of the universe … shrouded in mystery.” (Herbert, 1985), p194.

If quantum waves spread at light speed until a physical event restarts them, physical events are few and far between amidst the constant press of quantum events. By what logic then are these restart moments the reality of our universe? Surely reality is what is there most of the time? And according to quantum theory, most of the time, most of our universe exists in an unmeasured state.

It follows that in-between observations, in the unmeasured state, physical things aren’t there at all. We see substances that constantly exist, but a hologram has no substance when it isn’t projected, so quantum theory implies that the material world is, as Buddhists say, empty of self-existence, as it appears but has no permanence.

Most people of course don’t see the world that way, but that is expected if quantum events occur too fast for the gaps to be seen, like a movie but faster. The Dirac equation predicts that electrons have an ultra-fast tremble, called Zitterbewegung, that occurs 10¹⁵ times a second, so a quantum foam could flash the events we see faster than can be discerned. After all, we can’t expect the quantum world to act at a rate convenient to our observations.

Yet even as an ultra-fast hologram, our world still reflects the reality around us, so it is locally real in the sense that when you kick a stone, it still hurts, because that is the lawful result of that act. We don’t need to know what creates our world to live in it, just the results of our actions, which quantum reality provides. Evolution may then have primed our species to see what we need to survive rather than the truth:

“You may want the truth, but you don’t need the truth. Perceiving truth would drive our species extinct. You need simple icons that show you how to act to stay alive. Perception is not a window on objective reality. It is an interface that hides objective reality behind a veil of helpful icons.” (Hoffman, 2020).

According to Hoffman’s interface theory, perceptions are like desktop icons, useful but not true. For example, a blue email icon on a screen doesn’t mean the program that made it is blue. Likewise, seeing an object on the screen of space doesn’t mean that an object made it. Indeed the opposite is expected, as screen icons protect users from program details they don’t need to know about, so if our perceptions are just helpful icons, they will hide the quantum world from us.  

Yet if science is the search for truth, does evolution then hide it from us? Does the same evolution that produced our intellect now oppose its science? Probably, but hasn’t it always been so? For a long-time humans didn’t know that bacteria cause disease, because we couldn’t see them, until science proved they did. And later, when atoms were proposed, Mach argued that they couldn’t exist because they were unseen, but we now accept them, so when science takes us beyond appearances, we resist.

And now, when quantum theory says that what we can’t see causes what we can, again we turn away, saying “Enough! It cannot be.” Even physicists struggle with the idea that the unmanifest causes the manifest. How can the certainties we see come from uncertain probabilities? Is the answer to life, the universe, and everything, just a set numbers? This, it seems, is a step too far, even for physics. But after two thousand years of scientific struggle, do we now abandon science because our brains can’t handle the truth? It seems so, but long ago, some of us conceived what others find inconceivable.

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Materialism assumes everything is made of matter, so it leads to conclusions like:

“Observers have to be made of matter…Our description of nature is thus severely biased: we describe it from the standpoint of matter.” (Schiller, 2009), p834.

We see matter all around us, and so conclude the observer is matter also, yet nothing in physics suggests that matter experiences physical events. Physics then goes on to describe everything in terms of matter, even space and time, which are probably human constructs, leading to:

“… the dogma that the concept of reality must be confined to objects in space and time…” (Zeh, 2004), p18.

This dogma, of materialism, was built into the foundations of physics, but quantum theory denies it based on the Bell test, which challenges the following axioms of current physics (D’Espagnat, 1979):

1. Reality. That “there is some physical reality whose existence is independent of human observers.” (D’Espagnat, 1979), p158.

2. Locality. That no influence of any kind can propagate faster than the speed of light.

3. Induction. That logical induction is a valid mode of reasoning.

These axioms seem self-evident, but the Bell results show that one or more of them are wrong. If physical reality and induction are true, then locality must be wrong. If locality and induction are true, then reality isn’t physical. If physical reality and locality are true, then induction must be false. To this day, physics can’t explain the Bell experiments, which are based on quantum theory:

“According to quantum theory, quantum correlations violating Bell’s inequalities merely happen, somehow from outside space-time, in the sense that there is no story in space-time that can describe their occurrence:” (Salart et al., 2008), p1.

The foundations of physics have been found faulty, and there has been no rebuttal, so the answer must lie beyond materialism. If the world that quantum theory describes is real, then the first axiom must be changed by removing the word “physical”, so it becomes:

1. Reality: That there is a reality whose existence is independent of human observers. 

This change lets quantum reality exist independent of human observers, so there is still a real world around us, but it is behind what we see. For example, consider the following statement:

“If one adopts a realistic view of science, then one holds that there is a true and unique structure to the physical universe which scientists discover rather than invent.” (Barrow, 2007), p124.

To adapt this statement to the new axiom, we just remove the word physical, so it becomes: If one adopts a realistic view of science, then one holds that there is a true and unique structure to the universe which scientists discover rather than invent. This simple change, based on quantum theory, lets reality exist in a way that isn’t challenged by Bell’s result. The universe still has a true and unique structure that scientists can discover rather than invent, but it is quantum not physical. The only requirement is that all physical laws follow from quantum laws, which the evidence suggests is true. 

The second axiom must also be changed, but now by adding the world physical, so it becomes.

2. Locality: That no physical influence of any kind can propagate faster than the speed of light.

If locality applies only to physical influences, then Bell’s result no longer contradicts it, as quantum collapse isn’t a physical influence. Einstein’s law, that no influence is faster than light, apples to physical effects but if quantum collapse is a server-client effect, it can occur faster than light.

These simple changes to the reality and locality axioms mean the foundations of physics are no longer challenged by experiment. They also leave the axiom of logical induction intact, and with it, the methods of science. A physics founded on quantum theory doesn’t contradict what it predicts. 

This then is quantum realism, that quantum reality exists just as quantum theory describes it. It avoids the quantum paradox because quantum causes are now real. It has no particle-wave duality, only quantum waves that take every path then pick one on arrival, so delayed choice experiments no longer imply reverse causality. Physical events are primal choices not physical effects, so randomness is real. Going beyond materialism reveals a universe based on choices not mechanics.

Changing the foundations of physics won’t end it, but stagnation will, so why not let the equations that physicists use every day be real, not fantasy? Materialism was the mother of physics, but every child has to leave home one day, to go beyond what was before.

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The measurement problem in physics is that while Schrödinger’s equation determines how quantum waves evolve, how they collapse when measured is indeterminate. How then do many indefinite quantum states instantly become one definite physical state? This problem was raised early last century and no progress has been made on the matter since:

“The history of the quantum measurement paradox is fascinating. There is still no general agreement on the matter even after eighty years of heated debate.” (Laughlin, 2005), p49.

Essentially, we understand how quantum waves spread but not how they collapse, and but for this problem they could be real, as after all:

“… why not simply accept the reality of the wave function? (Zeh, 2004), p8.

This didn’t happen because the measurement problem means that quantum theory:

“… paints a picture of the world that is less objectively real than we usually believe it to be.” (Walker, 2000), p72.

In other words, what quantum theory describes makes no sense so it can’t be real. Quantum collapse is part of quantum theory, so it can’t just be ignored. If the wave part of quantum theory is accepted as real, then the jump of quantum collapse must be the same:

“… if we are to take y [the quantum field] as providing a picture of reality, then we must take these jumps as physically real occurrences too…” (Penrose, 1994), p331.

Schrödinger tried to explain the quantum field but failed, as did all who came after him, because its waves superpose in physically impossible ways, entangle to ignore the speed of light limit, and instantly collapse to a point when observed, but:

“How can something real disappear instantaneously?” (Barbour, 1999), p200.

When Pauli and Born defined the quantum field as the probability that a physical event will occur, physics inevitably became about what wasn’t physical, so:

“For the first time in physics, we have an equation that allows us to describe the behavior of objects in the universe with astounding accuracy, but for which one of the mathematical objects of the theory, the quantum field y, apparently does not correspond to any known physical quantity.” (Oerter, 2006), p89.

The measurement problem, that quantum waves act in an impossible way when measured, then produces the paradox that quantum unreality causes physical reality, but as one physicist notes:

“Can something that affects real events … itself be unreal?” (Zeh, 2004), p4.

The quantum states that predict physical states are physically unreal, so as Penrose says:

“How, indeed, can real objects be constituted from unreal components?” (Penrose, 1994), p313.

The quantum paradox is that if unreality causes reality, what doesn’t exist causes what does, which is illogical. If one thing causes another, how can a real effect have an unreal cause? Given a cause and effect, if only one is real, surely it is the cause not the effect?

For over a century, physics has faced this paradox like a deer in headlights, blinded by the brilliance of quantum theory, but stuck in the orthodox stance of materialism. This situation hasn’t changed for a hundred years, so if nothing is done, the next hundred years will be the same. 

Yet paradoxes are usually based on false assumptions. For example, the object in Figure 3.26 seems to have two square and three round prongs, based on where you look. If you look at the top, there are two square prongs, but if you look at the bottom, there are three round ones! Both seem to be true, producing the paradox that one object has two and three prongs, which is impossible! The answer isn’t to invent some sort of square-round duality, but to recognize that the same line can’t bound both a square and a round prong at the same time. When this false assumption is exposed, the paradox ceases to exist, because it is just an illusion.

Likewise, the quantum paradox, that unreal quantum events cause real physical events, is based on the false assumption that physical things constantly exist and so aren’t generated. The answer to this paradox isn’t to invent a wave-particle dualism that institutionalizes its illogic but to expose the fallacy behind it, of materialism. If matter doesn’t constantly exist, the quantum paradox disappears because physical events can now be generated. This is possible because processing waves on a network can spread, superpose, collapse and restart, just as quantum theory describes. Quantum realism is that physical events are generated by quantum events, rather than the other way around.

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Quantum theory works but is it scientific? After all, quantum waves aren’t observable:

“The full quantum wave function of an electron itself is not directly observable…” (Lederman & Hill, 2004), p240.

Nature’s firewall seems to separate us from quantum waves, because any attempt to observe them just gives a physical event, but is a theory about what can’t be seen scientific? The doctrine that only “…what impinges on us directly is real” (Mermin, 2009), p9, suggests that it isn’t, because:

1. Science is about reality, not imaginary things like fairies.

2. Our reality is only what we can physically observe.

3. Thus, a theory about what can’t be observed is imaginary, and so it isn’t scientific.

By this logic, quantum theory isn’t scientific because it describes what we can’t see, yet it is the most successful theory in the history of physics! The flaw in the argument is the assumption that our reality is all reality, which is materialism. Certainly our reality is just what we see, but that it is all reality is unproven. If the reality of science is only what we see, then quantum theory isn’t scientific but that is a big assumption. This is why scientific theories aren’t limited to what we see, and never have been.

For example, the theory of gravity is scientific but we don’t observe gravity, just its effects. Science is actually based on empiricism, as proposed by Lock and Hume, the idea that knowledge comes from experience not beliefs. Scientific theories then only have to predict physical events, not be about them, so quantum theory is scientific because it does that.

The myth that science must only describe physical things is logical positivism, a philosophical movement based on materialism that began in the 1920s. It argues that only what we observe exists, so science should be about nothing else. Rather than talking about thoughts, feelings, and beliefs that we can’t see, why not focus on what we can? Purging science of non-observables seems good, but it makes most of mathematics unscientific, as the unknown x of algebra, the infinitesimal dx of calculus, and even the triangle of geometry, aren’t physical things. Logical positivism is materialism masquerading as an axiom of science when it isn’t, and never was.

Positivism doesn’t work in other disciplines either. Behaviorism tried to reduce all psychology to behavior until Chomsky showed that it couldn’t explain the productivity of language. Applying positivism to computing would deny human-computer interaction (HCI) concepts like polite computing, and socio-technical concepts like group agreement. Today, physics is the last bastion of positivism, but even there it is failing because it can’t avoid the concept of the observer.

According to positivism, physical reality exists objectively, whether it is observed or not, so it should be described that way. The observer is then a subjective concept that has no place in science because it can’t be seen. Unfortunately, the main theories of modern physics both assume that an observer exists, as quantum theory needs an observer to trigger physical events and relativity needs an observer frame of reference. If even physics can’t ban the observer, how can other disciplines do it? Instead of an objective universe, physics now suggests that we live in a participative universe, whose every event is an observer-observed interaction, so to ignore the observer is to ignore half of reality.

Quantum theory is scientific because scientific theories don’t have to describe physical things. After all, that we can’t see a ray of light from the side doesn’t make it not exist then. Reality carries on whether we see it or not, and according to quantum theory, even causes what we see. An observation is then a request for a view, just as a click in a game is. Yet if the long-sought boundary between the classical and quantum worlds is the click of observation, this produces a measurement problem.

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According to quantum theory, radioactive atoms emit photons randomly, and they do. Quantum waves predict the possibilities of every physical event, but not which one actually happens. Yet that every physical event has a random element contradicted the idea that our universe is a machine driven by inevitable laws.

Randomness seemed to undermine the laws of physics, so in 1957 Everett proposed the many-worlds interpretation, that every quantum possibility actually happens in another physical world, so if a photon is measured say spin up, another universe spawns where it is spin down. Nothing is then random if every quantum possibility actually happens somewhere, in what we now call the multiverse. Many-worlds theory in effect replaces the clockwork universe that quantum theory destroyed last century with a clockwork multiverse.

Everett’s idea was initially seen as absurd, as indeed it is, but physicists now prefer it 3:1 over the Copenhagen view (Tegmark & Wheeler, 2001, p6) because it denies randomness. But if every event of the estimated 4×1084 photons in our universe creates a new universe, it isn’t hard to see that the:

“… universe of universes would be piling up at rates that transcend all concepts of infinitude.” (Walker, 2000), p107.

Many worlds theory doesn’t just offend Occam’s razor, it outrages it. Do you believe that in the time it took to read this sentence, a billion, billion universes arose from the light that hit your eyes? Current physics does, but why? This theory isn’t testable, nor does it predict any new facts, yet it is accepted. To be clear, no facts at all support the multiverse so its only value seems to be to deny randomness.

An attempt to rescue this zombie theory (Note 1) by letting a finite number of universes repartition after each choice (Deutsch, 1997) just recovers the original problem, as what chooses the worlds to drop? Is nature, like a doting parent with a camera, recording everything our universe might do? The mechanical multiverse, like the mechanical universe, appeals to physicists, but fairy tales aren’t good science (Baggot, 2013), nor is calling the good science of quantum theory a fairy tale!

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Note 1. Zombie theories make no new predictions and can’t be falsified. Like zombies, they have no progeny nor can they be killed by falsification, as they are already scientifically “dead”.

Over two thousand years ago, Aristotle concluded that our reality consists of:

“… a multitude of single things (substances), each of them characterized by intrinsic properties …” (Audretsch, 2004, p274).

This view checks our boxes because it is simple, intuitive, and fruitful. It is simple because it says the things we know cause everything. It is intuitive because it lets a ray of light hit a screen at one point. And it was fruitful because the study of material things allowed science to grow.

Materialism has served science well over the years but today it is failing. The harsh truth of modern physics is that particles can’t explain the facts observed, as light illustrates. A particle can’t go through two slits to interfere with itself, but light can. A particle can’t detect an object without touching it, but light can. A particle can’t find the fastest path to any destination, but light can. A particle can’t alter a path it has travelled, but light can. Particles can’t interact faster than light, but entangled photons can. Materialism is the mother of physics but when reality bites us, it has no answer.

Then along came quantum theory with all the answers based on quantum waves. It was perfect but for the fact that it described what couldn’t physically happen. Nature accepted it, because it worked, but physics disowned it, because it contradicted materialism, preferring instead to believe a fairy tale.

3.9.1. A Fairy Tale for Physicists

3.9.2. Is Quantum Theory Science?

3.9.3. The Measurement Problem

3.9.4. Beyond Materialism

3.9.5. The Unmeasured Reality

3.9.6. Plato’s Cave

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