Physics is the human attempt to discover the unchanging laws of the universe. Since the Greek thinkers 2,000 years ago, every now and then there have been changes in the physical laws that scientists once thought were unchangeable. These are times when humans discover a new “land,” in which unexpected phenomena challenge and contradict current thinking. About 120 years ago, one of the biggest of these changes revealed a new and exciting land—a land that we are still exploring today. In this article, I will describe some of the strange phenomena of this new land, called quantum physics, and how it forced us to change the way we think about the world in terms of energy, scientific measurements, and the reality of the objects around us. As no one—even the best physicists in the world—knows exactly what it really means, I will leave it to you to decide!
Physics is the human attempt to discover the unchanging laws of the universe. Since the Greek thinkers 2,000 years ago, every now and then there have been changes in the physical laws that scientists once thought were unchangeable. These are times when humans discover a new “land,” in which unexpected phenomena challenge and contradict current thinking. About 120 years ago, one of the biggest of these changes revealed a new and exciting land—a land that we are still exploring today. In this article, I will describe some of the strange phenomena of this new land, called quantum physics, and how it forced us to change the way we think about the world in terms of energy, scientific measurements, and the reality of the objects around us. As no one—even the best physicists in the world—knows exactly what it really means, I will leave it to you to decide!
Quantum physics is well known for being counter-intuitive, or even bizarre. Quantum correlations have no equivalence in classical physics. This was all well known for years. But several discoveries in the 1990's changed the world. First, in 1991 Artur Ekert, from Oxford University, discovered that quantum correlations could be used to distribute cryptographic keys. Suddenly physicists realized that quantum correlations and its associated bizarre non-locality, could be exploited to achieve a useful task that would be impossible without quantum physics. What a revolution! And this was not the end. Three years later, Peter Shor, from the AT&T Laboratories, discovered an algorithm that breaks the most used public key crypto-systems. Shor's algorithm requires a quantum computer, yet another bizarre quantum device, a kind of computer that heavily exploits the quantum superposition principle. The following year, in 1995, a collaboration between six physicists and computer scientists from three continents led to the discovery of quantum teleportation, a process with a science-fiction flavour. These discoveries and others led to the emergence of a new science, marrying quantum physics and theoretical computer science, called quantum information science. Today, a steadily growing community of physicists, mathematicians and computer scientists develop the tools of this new science. This leads to new experiments and new insights into physics and information theory. It is a fascinating time. Quantum information is still a very young science. In particular, the technology required to build a quantum computer is still unknown. Only quantum key distribution has reached a certain level of maturity, with a few start-ups already offering complete systems. Nevertheless, quantum information has been widely recognised as a source for truly innovative ideas and disruptive technologies.
Along with weaving together observations, experiments, and theoretical constructs into a coherent mesh of understanding of the world around us, physics over its past five centuries has continuously refined the base concepts on which the whole framework is built. In quantum physics, first in non-relativistic mechanics and later in quantum field theories, even familiar concepts of position, momentum, wave or particle, are derived constructs from the classical limit in which we live but not intrinsic to the underlying physics. Most crucially, the very idea of the individual, whether an object or an event, distinguished only in a mere label of identity from others identical to it in all the physics, exists only as an approximation, not an element of underlying reality. Failure to recognize this and seeking alternative explanations in many worlds or multiverses leads only to incoherent logic and incorrect physics. As an example, in a physical system such as an atom in a particular state, physics deals with the universal system of all such atoms but makes no meaningful prediction of the position of an electron or the time of decay of any specific atom. Those are incidental, entirely random among all possible positions and times, even while physics makes very precise predictions for the distribution of the outcomes in measurements on atoms in that state. Physics deals with the universal, not the individual.
In this chapter, I offer some personal reflections about the nature of reality, shaped by my work as a quantum physicist, my experimentation with psychedelic drugs during the 1960s, and my more recent studies of modern cognitive science. Traditionally, questions about the essential nature of reality are asked by philosophers. In the twentieth century, these questions were asked for the first time by scientists as well. During the first three decades of the century, the exploration of the atomic and subatomic world brought physicists in contact with a strange and unexpected reality that shattered the foundations of their worldview and forced them to think in entirely new ways. Quantum physics showed scientists “a new reality,” and from that time on, the nature of reality became a popular subject of discussion not only in philosophy but also in science. In recent decades, cognitive scientists took another radical step in the scientific conception of the nature of reality. They asserted that the features of our ordinary, everyday reality are not features of an independently existing world, but are created in the very process of perception. In a way this generalizes the influence of the act of perception on the perceived object, which was famously analyzed in quantum physics by Werner Heisenberg, to everyday perception. In other words, even our everyday reality is just one of many alternate realities.
In last years, we are witnessing a trend, of trying to describe the laws of nature using informational tools instead of by functional tools. This change towards more abstract description of the nature, is a natural development, as from the time of the Greeks, through the time of Newton, followed by Analytical Mechanics, all the way up to General Relativity and String Theory, there was always a preference to the more abstract and general description of nature. The reason we prefer the more general and abstract descriptions, is that they give us a more objective point of view at the laws of Nature, which allow us more effectively to separate between Phenomena that are the manifestation of the deep laws of Nature, and Phenomena that are just being resulted by our very specific point of view at the universe, and the specific description that we have decided to give it. The more abstract descriptions give us a better frame of reference in our attempted to understand the origins of the laws of Physics. Informational description of the Universe is suspected to be better than the Functional description, as it is a more abstract and general point of view of the Universe, and yet, there is no complete and simple way to translate every Physical Theory to informational language. In this article I have attempted to do just that, by taking two tied Philosophical arguments, and giving them a Formal and Mathematical meaning, by so upgrading them into Physical Principals. The first Principle is the idea that the only objective thing in Nature, that does not depend at the observer point of view, is the different options that realty can exist in. This set of options of reality is meaningless and lacks structure in any way besides their combined number (cardinality), and I name these options of reality “cosmoses”. The second Principle is that there are observers, that are bound to one option of reality, but unable to separate between their cosmos to other cosmoses. This inability to completely know in what cosmos they do exist, creates a local structure. This structure, and the way it changes over time is what creates the structure of the universe that the observers (including you dear reader) measure. By using this simple language, I was able to suggest some new tools and predictions.
Along with weaving together observations, experiments, and theoretical constructs into a coherent mesh of understanding of the world around us, physics over its past five centuries has continuously refined the base concepts on which the whole framework is built. In quantum physics, first in nonrelativistic mechanics and later in quantum field theories, even familiar concepts of position, momentum, wave, or particle, are derived constructs from the classical limit in which we live but not intrinsic to the underlying physics. Most crucially, the very idea of the individual, whether an object or an event, distinguished only in a mere label of identity from others identical to it in all the physics, exists only as an approximation, not an element of underlying reality. It is not an element of physics. Failure to recognize this and seeking alternative explanations in many worlds or multiverses leads only to incoherent logic and incorrect physics. As an example, for an atom in a particular state, physics deals with the universal system of all such atoms but makes no meaningful prediction of the position of an electron or the time of decay of any specific atom. Those are incidental, entirely random among all possible positions and times, even while physics makes very precise predictions for the distribution of the outcomes in measurements on atoms in that state. Physics deals with the universal, not the individual.
In classical physics there is, in accordance with common sense, an objective world ‘out there’. That world evolves in a clear and deterministic way, being governed by precisely formulated mathematical equations. This is as true for the theories of Maxwell and Einstein as it is for the original Newtonian scheme. Physical reality is taken to exist independently of ourselves; and exactly how the classical world ‘is’ is not affected by how we might choose to look at it. Moreover, our bodies and our brains are themselves to be part of that world. They, also, are viewed as evolving according to the same precise and deterministic classical equations. All our actions are to be fixed by these equations - no matter how we might feel that our conscious wills may be influencing how we behave. Such a picture appears to lie at the background of most serious 1 philosophical arguments concerned with the nature of reality, of our conscious perceptions, and of our apparent free will. Some people might have an uncomfortable feeling that there should also be a role for quantum theory - that fundamental but disturbing scheme of things which, in the first quarter of this century, arose out of observations of subtle discrepancies between the actual behaviour of the world and the descriptions of classical physics. To many, the term ‘quantum theory’ evokes merely some vague concept of an ‘uncertainty principle’, which, at the level of particles, atoms or molecules, forbids precision in our descriptions and yields merely probabilistic behaviour. Actually, quantum descriptions are very precise, as we shall see, although radically different from the familiar classical ones. Moreover, we shall find, despite a common view to the contrary, that probabilities do not arise at the minute quantum level of particles, atoms, or molecules - those evolve deterministically - but, seemingly, via some mysterious larger-scale action connected with the emergence of a classical world that we can consciously perceive. We must try to understand this, and how quantum theory forces us to change our view of physical reality.