Hugh Everett’s proposition – everything that is possible, happens.
One of the hypotheses that tries to explain the phenomena in quantum physics, especially the quantum collapse that occurs at every measurement – the abrupt end of the quantum state wave and the appearance of the particle – is Hugh Everett’s Multiversa hypothesis. Remember; the state wave is a wave that contains all the possible states of the particle to be measured. In Everett’s proposal, everything that can happen happens physically. Therefore the actual universe, where the measurement takes place, splits into as many physical universes as there are possibilities. In all those split-off universes there exists a copy of the conscious experimenter. Each copy thus perceives one of the results of the experiment. There is then no quantum collapse at all that mysteriously occurs on measurement.
Initially, there were only a few supporters of Everett’s idea. But right now, the idea has quite a lot of support among quantum physicists. Its attractiveness is easy to understand. A non-material consciousness is not needed in his hypothesis, so we can continue to assume that consciousness is a product of the material brain. Which is still the most popular hypothesis in neuroscience today despite a huge amount of excellent forensic and casuistic evidence to the contrary. They apparently wish to remain ignorant of this evidence.
The double-slit as test
Reflecting on the multiversa hypothesis, I thought of Richard Feynman’s statement; “The mysteries of quantum mechanics can be understood from just one experiment. That’s the double slit experiment. The experiment is simple, but the results leave us in awe.” The question then becomes this: can I understand the double slit experiment from the Multiversa hypothesis? Can the double slit experiment serve as a test for this outrageous hypothesis?
The double slit experiment was first performed by Thomas Young in 1805. He let sunlight shine through two slits – two narrow parallel scratches on a sooted glass plate. The result of this looked then and looks still like this:
Parallel colored bands of light separated by dark bands (fringes). This is called an interference pattern. This pattern is easy to understand with the view of light as a wave. The two slits act as synchronous sources of light waves. The synchronous waves running from the two slits meet and at each location their amplitudes are added together. This is called superposition. The superposition of these two waves creates contiguous fanning lines of maximum vibration (intensity) and between them also contiguous fanning lines of rest (darkness). The colored lines arise because sunlight consists of a whole spectrum of wavelengths, from red to violet, and for each wavelength the locations of its maxima are at different distances from the central maximum.
For more info, I refer you to this excellent YouTube video from Veritasium.
Nevertheless, light is made up of particles
The great problem is that light is not a continuous wave phenomenon, but consists of energy packets, photons, where the energy E of each photon is proportional to the frequency f of the wave. This proportionality constant is Planck’s constant, discovered around 1900. Incidentally, it is difficult to imagine a frequency of the photon itself when it is a particle. What is the frequency of a particle? What does it look like?
E = h.f – h is Planck's constant: 6,626 x 10-34 J.s
Photons and the quantum state wave
Photons are light particles whose behavior is controlled by a quantum state wave, the Schrödinger state wave. (NB: A moving photon has never been directly observed, because the observation means the annihilation of the photon). Each part of that state wave can be described as a vector, an arrow that describes both magnitude and direction of the wave’s deflection. This vector must be described in imaginary dimensions, which is not a problem for the mathematician, but for our imagination it’s a problem. The state wave is not a material wave, which can also be inferred from the fact that this vector is not something existing in our 3-dimensional space. However, the absolute length of the vector squared at a particular location does indicate something useful, the probability of finding the photon at that location when measured. However, a probability is not a material phenomenon. The state wave isn’t either.
The frequency and the wavelength of that non-material state wave are the frequency and wavelength that we seem to measure in our experiments with light, although this apparently consists of photons. When we detect a photon, it is the result of the aforementioned quantum collapse, the abrupt end of the state wave, in which the photon transfers its energy to the detector – for example our retina. The photons that appear as points of light on the detection screen are thus the result of the quantum collapse of the state wave upon arrival at the screen. The cause of the quantum collapse has still not been experimentally determined, although recent experiments seem to indicate that it is caused by the information we can get about the state of the quantum particles. Everett seeks to completely eradicate this enigmatic quantum collapse.
The key – a continuous interference pattern
Back now to the Multiversa hypothesis. We will do an experiment, we will send a single photon through a double slit. According to that hypothesis, our universe splits into as many copies as are necessary to contain all possible photon detections. And these are quite a few. Quantum mechanics predicts a continuous spread of maximum and minimum intensities. So not a limited number of discrete points with nothing between.
That means an infinite number of possible outcomes for where the photon can end up on the detection device. Possibly we can adjust that infinity to a countable number of possibilities by taking the Planck length as the smallest possible unit of length. At 10cm wide, it still gives you a huge number of possibilities, somewhere in the neighborhood of 1033. So, just sending one photon through a double slit and detecting it, has to result in about 1033 split off copies of our universe with just as many copies of you and me each observing one of those possibilities in their own universe.
In itself, that outrageously huge number is not sufficient proof that the Multiversa hypothesis is not the ultimate truth. But it seems to me anyhow a strong contraindication and in any case a good reason not to take it as seriously as is done by many physicists. Multiversa is still completely unproven and most likely unprovable.
Measuring at the slit and the multiverse
The Multiversa hypothesis should also be able to provide an explanation for a particularly remarkable, but time and again experimentally confirmed, phenomenon. As soon as we somehow, no matter how, set up the experiment in such a way that we can know through which slit our photon has passed, the interference pattern disappears. The result is a light spot that is strongest in the center and diminishes towards the sides.
If it can be determined experimentally that the photon passes through the left-hand slit, this means that the state wave must have adapted itself to that information and has changed to a 100% probability of being present in the slit. A 100% probability, in my opinion, is identical to a material presence. In any case, indistinguishable from that. It is then easy to understand that from that location in the slit of 100% probability of presence a single state wave departs and no more wave leaves from the other slit. Which explains the single light spot.
Thus, in the Multiversa hypothesis, the way in which the universe splits into as many universes as there are possibilities, as represented by the state wave, has been significantly altered by our experimental set-up. Now how could my decision to measure or not to measure which slit the photon passed, trigger this massive adjustment in the creation of copies of the universe? A persistent materialist will argue that that decision of mine was already 100% predestined, whereby of course he also expanded the demon of Laplace in his possibilities to fully know and predict all those split-off universes. That is, for example, the – completely unproven – position of Gerard ’t Hooft, Nobel Prize winner.
Is this still plausible?
Is that, this frenzied proliferation of multiversa, wholly predestined in their unimaginable totality, still more acceptable than the hypothesis that the observer’s consciousness creates the manifested reality according to the information at his disposal? That’s my question.
A radical change in perspective
Still, I think Everett noticed something valuable. All it takes to make his hypothesis significantly more plausible, as far as I’m concerned, is a radical change in perspective. His idea was that everything that could happen actually happens. He saw our reality as objectively material. Not only was the reality that we experience material, but all those split-off universes were also material, and so were indistinguishable in the nature of their substance. Now consider that that last phrase, indistinguishable in the nature of their substance, can be disconnected from the idea of materiality. So if we see all those multiversa as non-material probability distributions in the state wave of the universe, then if we’re consistent, we should do the same for the universe we experience. Our daily world of experience is then in fact just as immaterial as all those possible universes that do exist in that state wave.
That is indeed a radical inversion of perspective. The advantage of it is that it offers enormous possibilities for the role of the mind with which we apparently choose and create our experiences from all these possible states. Free will is back, the survival of the spirit after – and before – death is possible again. The near-death experience (NDE) fits completely into this framework and no longer needs to be denied or dismissed as the hallucinations of a dying brain. The latter, by the way, is an idea that does not provide any explanation for an important reported and verified subset of these experiences. These are those NDE experiences where there is no plausible material explanation whatsoever for the content of the experiences. And those are legion. Read “The Self Does Not Die” by Rivas and Dirven. Even if you are an inveterate materialist, then that’s what you honestly should be doing.
Paul J. van Leeuwen graduated in applied physics in Delft TU in 1974. There was little attention to the significance of quantum physics for the view on reality at that time. However, much later in his life he discovered that there is an important and clear connection between quantum physics and consciousness.
What he learned between then and today resulted in a post academic course in quantum physics for non-physicists. A little bit later he decided to put the contents of that course, and more, in a book published in Dutch: Kwantumfysica, Informatie en Bewustzijn – and started a website on the subject. He translated the Dutch version of his book in English, titled: ‘Quantum Physics is NOT Weird’.