The Totalitarian Principle declares that anything which is not forbidden by any specific rule of physics, is required by law to occur, with no exceptions.

Consider the following to be law #1 for quantum mechanics:

Whatever is not forbidden is compulsory.

This is a form of what is called the Totalitarian Principle. The phrase was first used by physicist Murray Gell-Mann in reference to the laws that might be issued by a totalitarian government seeking full control over their citizens.

Applying the Principle to Physics

Within the world of quantum physics, the totalitarian principle simply means that only those things which blatantly violate specific quantum laws are forbidden in a quantum system – anything else can and must happen. Thus, if there is no specific law (usually a conservation law, such as the law of conservation of mass, energy, baryon number, or charge) forbidding a certain event to take place, the event must by law take place.

Thus, to reverse this law and draw another conclusion from it – if something does not happen, then there must be a law expressly forbidding it.

While on the surface this law may seem somewhat questionable and contrary to everyday experience, the more one looks deeply into its true meanings, the more it begins to actually make some sense. After all, one might consider the rebuttal: “There’s no specific law forbidding that table to fly across the room and break that window, so why doesn’t it happen?” In thinking about this more, however, one realizes that there are a great many specific laws which explain why this cannot happen, such as the Newton’s laws of motion, the force of gravity, and so on. W

Where the truly remarkable conclusions from this principle can be put into practice, however, is on a subatomic level, in the world of quantum mechanics.

The Principle on a Quantum Level

Pauli’s exclusion principle states that no two electrons can possibly exist having identical quantum numbers.

According to the totalitarian principle, this means that all electrons which obey the exclusion principle and have different numbers will necessarily be grouped together. Likewise (and this can be a somewhat startling realization, but it is the truth), if a photon of light is traveling from the sun to the Earth, there is no law expressly stating that the photon must take a direct route. There’s no specific reason it can’t take an alternate route, perhaps by way of Mars, then Jupiter, then Pluto, then back to Mercury, and finally on to Earth – thus, the photon must take that route, along with an infinite number of others at the same time.

Yes, this sounds crazy, but rest assured that not only is this occurrence implied in the totalitarian principle, but there is very real experimental evidence for this type of phenomenon (and it is thinking like this which led to one of the great triumphs of 20th century physics – Quantum Electrodynamics).

Discovering New Laws Using the Totalitarian Principle

Experimental physicists have used the totalitarian principle to determine conservation and behavioral laws concerning particles, realizing that if an expected particle doesn’t show up in a given experiment, there must be some law forbidding it, otherwise it would have been compulsory, so the search begins for such a law. If particles are smashed together in a particle accelerator (otherwise known as “atom smashers”), physicists generally can predict most of the possible results – which other particles may be created from the energy in the reaction.

If, however, a particle is never seen to occur in such reactions, it becomes clear that there must be a rule forbidding this to happen – and that rule is generally the rule expressed by Einstein’s equation, E = mc² - energy available in the reaction is not sufficient to transform into the mass of the particle in question. If it had been, the particle would have been created.

In this sense, everything that occurs must occur within the confines of very specific principles, and the totalitarian principle has been a key to finding out what these principles may be.

In quantum physics, the totalitarian principle has been put to wonderful use over the years, as it has seemed to be a very straightforward, well-tested way to probe the deeper logical mysteries behind the opaque veil that shrouds the subatomic scale. With it, scientists have been able to further unravel the secrets behind the very particles from which all matter is composed.

References:

Gribbin, J. (1994). In Search of Schrodinger's Cat: Quantum Physics and Reality. New York, NY: Bantam Books.

Herbert, N. (1985). Quantum Reality. Garden City, NY: Anchor Press/Doubleday.

Johnson, G. (1999). Strange Beauty: Murray Gell-Mann and the Revolution in Twentieth-Century Physics. New York, NY: Alfred Knopf, Inc.

“Particle Interactions and Conservation Laws.”