Let us start our discussion by understanding the Heisenberg uncertainty principle. Most physics professors teach it in the context of attempting to simultaneously measure a particle’s velocity and position. It goes something like this:

• When we attempt to measure a particle’s velocity, the measurement interferes with the particle’s position.
• If we attempt to measure the particle’s position, the measurement interferes with the particles velocity.
• Thus, we can be certain of either the particle’s velocity or the particle’s position, but not both simultaneously.

This makes sense to most people. However, it is an over simplification. The Heisenberg uncertainty principle has greater implications. It embodies the statistical nature of reality. This last statement may not seem true, since we live and experience nature at the macro level (i.e., our everyday world). At the macro level we generally do not talk in terms of probabilities. For example, we can predict the exact location and orbital velocity of a planet using Einstein’s theories of relativity. Thus, most scientists will say that macro level phenomena are deterministic, which means that a unique solution describes their state of being, including position, velocity, size, and other physical attributes.

In practice, we only see the effects of the Heisenberg uncertainty principle at the micro or quantum level (i.e., the level of atoms and subatomic particles). At the quantum level, Einstein’s theories of relativity break down, and we are forced to use the theory of quantum mechanics. Quantum mechanics is a set of laws and principles that describes the behavior and energy of atoms and subatomic particles. At the quantum level we are unable to simultaneously measure the position and velocity of an atom or subatomic particle. The reality of the quantum level is expressed in terms of probabilities. While we can predict the exact location and orbital velocity of a planet at the macro level, we are not able to make similar predictions about an electron as it obits the nucleus of an atom at the quantum level. We can only talk in probabilities regarding the electron’s position and energy. Thus, most physicists will argue that quantum level phenomena are probabilistic, which means that their state of being is described via probabilities, and we cannot simultaneously determine, for example, the position and velocity of a subatomic particle.

What does this really mean? Do we really have two different levels of reality with different laws. The short answer is no. While we observe differences between the macro and quantum level, the differences really don’t exist. Measurements at the macro level are typically large compared to measurements at the quantum level. However, the laws of physics remain the same at both the macro and quantum level. In fact, the laws of quantum mechanics at the quantum level reduce to the laws of classical physics at the macro level. This means that all reality is statistically based, even at the macro level.

You may ask, is it possible to observe this statistical nature of reality at the macro level? The answer is yes. For example, it is possible to observe the statistical nature of reality via the creation of virtual particles that give rise to the Casimir-Polder force. The Casimir-Polder force is the attractive force between two parallel plates placed extremely close together (approximately a molecular distance) in a vacuum. Science believes the “attraction” is due to a reduction in virtual particle formation (i.e., spontaneous particle production) between the plates. This, in effect, results in more virtual particles outside the plates whose pressure pushes them together. Spontaneous particle creation is the phenomenon of particles appearing from apparently nothing, hence their name “virtual particles.” However, they appear real and cause real changes to their environment, as discussed above. Science believes that the particles form as the energy within a vacuum statistically varies and occasionally becomes dense in a specific region giving rise the virtual particles. This may sound odd, but it is a scientific fact that vacuums contain energy and that energy statistically varies giving rise to virtual particles.

How important is the Heisenberg uncertainty principle? It is fundamentally important to understanding reality, especially at the quantum level and occasionally at the macro level. It unequivocally states that the nature of all reality is statistically based.