Why Is the Universe Coherent?
Seth Lloyd, a professor at MIT, proposed the first feasible design for a quantum computer. There are now many quantum computers operating around the world. Lloyd specializes in quantum communication, quantum computation, and quantum biology. A few years ago I read Lloyd's book, "Programming the Universe". I was researching the topic of universal consciousness. Lloyd concluded that the universe is a quantum computer that operates using the information inherent in all elementary particles in the universe. What does it compute? It computes itself. It occurred to me that this might be what makes the universe coherent.
The universe obviously is not a ragtag collection of uncoordinated particles randomly bouncing around; it operates as if it were somehow centrally organized following a rule book that requires every component of the universe to behave according to a grand program containing the laws of physics.
Whether you believe the coherence of the universe is the result of an omnipotent creator or is inherent in the natural laws of physics, there is underlying coordination and communications between all parts of the universe that make it operate in a comprehensible and harmonious manner. How do the components of the universe communicate and coordinate?
Computers manage information by managing bits. Abstract bits are represented by the numbers 0 and 1 but the physical medium for bits can be anything that has two states. A state may be magnetized or not, light present or not, electricity flowing or not, and so forth. Morse code uses dashes and dots as bits. A flash drive uses electrons contained in a "trap" and an empty trap each representing bits. The important point is that organized bits are the building blocks for information storage, transmission, and processing in your smartphone, computer, or other digital devices.
Computers use logic gates to "flip" bits (change 0 into 1 or vice versa) to organize and reorganize bits to perform calculations, create images on a monitor, and produce written characters in a document.
You might guess by now that I am going to conclude elementary particles in the universe organize themselves by carrying and processing bits of information. That's looking in the right direction but the whole story is much more interesting than that. Stay with me; I will try to keep the story simple but coherent.
Elementary particles in the universe carry bits of information; the particle exists in a state that either has yet to express its bit-state, or it has a state that is one or another bit ready to be flipped under the right conditions. At the Big Bang, elementary particles flew in all directions, each carrying its own bit or potential bits. The early universe was nearly uniform revealing no tendency to become interestingly complex. Almost everything everywhere was essentially the same.
Then gravity, a relatively weak force in the universe, began to exploit small variations in the distribution of particles to collect small clumps of stuff. The nature of gravity is to multiply its power as clumps grow; more massive clumps have greater gravitational field and therefore make even bigger clumps. Solid matter and clouds of gasses gathered to form features that would become stars, galaxies, and planets.
As gravity gathers nearby particles, the particles collide. The average atom contains about 20 bits of information. When atoms collide, the result is equivalent to information processing that is performed by a computer. Thus when atoms formed and interacted in the universe, the universe revealed itself to function as a computer.
Physicists and philosophers distinguish between goal-oriented information processing and chaotic information processing. Not all information processing results in something coherent. The universe is computing by flipping bits, there is no doubt about that. So what does it compute? Most material objects simply compute themselves. The chair I am sitting in has coherence because its bits flip in a manner that makes it a reliable place to sit.
Information needs to be preserved (stored, however briefly) to be useful in information processing. A single atom of iron behaves according to quantum mechanics which isn't very useful to store or process data. Put twelve iron atoms together and the quantum behavior aggregates into more classical behavior. The small clumps of iron behave more like the iron that we magnetize to store data. Matter begins to be more coherent. The states of these tiny pieces are now influenced by outside magnetic influences; the 12-atom iron structures begin to communicate with each other. They begin to behave according to rules that allow for ever-increasing complexity. But how does increasing complexity spontaneously spawn more complexity?
Bits can be data or instructions. A few bits of data, combined with very simple instructions that combine data, can result in surprisingly complex patterns. For example, consider Conway's Game of Life. It starts with a simple rule that specifies how a single shaded grid on graph paper affects the shading of one or more of its 8 neighbors (adjoining and diagonal). Repeating the rule over and over generates unexpectedly complex patterns. In other words, complexity can arise from small components and a simple program. The resulting complexity is not evident in the early implementation of the rule.
The coherence of the universe depends on the natural emergence of information-processing rules like clumps of iron "talking" to each other through magnetic influences.
Knowing the rules doesn't give us the ability to predict the future of the universe, they just stimulate complexity that will play out as it will. Mathematics and logic (Gödel's incompleteness theorem and the Halting Problem) have been used to prove that the future course of the universe is inherently unpredictable however structured are the rules. Five billion years ago, the evolution of humans could not have been predicted as inevitable by any amount of information processing in any conceivable computer anywhere in the universe. Quantum behavior continually messes with complex behaviors because of its inherent randomness.
For more than half of the history of the universe, complexity naturally grew without life on earth. Galaxies and solar systems formed from gravitational forces and the bit flipping collision of elementary particles. Then information processing took a small but critical step. Information processing produced the most primitive form of life on earth. There was no magic spark, just a random combination of flipped bits that combined chemicals in a unique manner that allowed self-reproduction.
Were it not for the random influence of quantum physics (more on this in a later blog) life may have ended there. A tedious replicating of identical primitive organisms would likely not have survived long. But quantum behavior is inherently random. Elementary particles exist in an ambiguous state having two binary states at once. When an elementary particle interacts with another particle, quantum behavior demands that one or another state be expressed; the particle can no longer hide behind its quantum veil. In the presence of another particle, the bit has a 50% chance of having one state or the other. This randomness is inherent in all things. Life on earth could not result in identical organisms reproducing without random changes for better or for worse. Lloyd describes one of his favorite steps in complexity as the information revolution called sex which triggered billions of experimental forms of life and subsequent evolution.
Thus evolution happened because quantum mechanics randomly disturbed life generation after generation. In humans, DNA is an elaborate set of instructions and a huge amount of data. Every base pair of DNA has two bits that can be preserved or flipped by information processing instructions inherent in our biology. We are programming ourselves and our offspring with lots of random variation (See a prior blog post "I almost didn't exist").
Messing with reproduction has both good and bad consequences. Surviving organisms reproduce to have a better chance of improving the survival of their species. Weaker organisms become fewer in number on average and, without a turn of luck, will die out. Complexity marches on, building more complexity upon the more successful complexity. Seth Lloyd is fond of likening this process to successive information revolutions that each depend of previous revolutions. Human language preceded written language which in turn preceded printing, and so forth. Each information processing revolution could not have occurred were it not for the previous revolutions.
Seth Lloyd makes a compelling case that quantum mechanics introduces random "experiments" into the emergence of complexity and produces more even complexity. I view this as a sort of "survival of the fittest information processing" that is inherent in the laws of nature. It is fitting that today's information revolution is building on a deeper knowledge of quantum mechanics which is at the very core of a coherent universe.
Check out the many videos and interviews Seth Lloyd has produced for more depth on this subject. And if this subject interests you, I recommend reading "Programming the Universe".