Pilot waves aren’t a recent concept, having being theorized first back in 19th century. However, they are an idea that still causes ripples in our understanding of the universe and quantum mechanics in particular. These represent a much debated over hypotheses that isn’t widely accepted but would be the key to solving numerous unanswered questions.
Louis de Broglie is famous for proposing de Broglie wavelength, an idea that implies that matter behaves both like a wave and particle, much like light. This dual nature of matter is only observable at a small scale but it forms a major part of the pilot wave theory.
Quantum Mechanics relies heavily on the Heisenberg's principle which states that it is impossible to know both the location and momentum of a particle at any given point of time. This isn’t an error due to underdeveloped instruments on our part but rather a scientific phenomenon. Pilot theory on the other hand suggests strongly that particles do have definite positions at all time. But the acceptance of this theory would also mean that our world would behave in strange ways.
What is a pilot wave?
Quantum mechanics treats the position of a particle like a wave function that collapses upon measurement. This is a significant idea and can be easily imagined using a graph. At any instance of time if a particle’s location is unknown to us, it could be anywhere in space. But certain places will definitely have a higher probability of the particle being present than others. Just by looking at the place which has the highest probability of presence we can’t tell whether the particle will be there.
It is only after we observe that we can tell for certain its position. And this is exactly why its said that the position wave function collapses upon measurement to give a single value.
In 1952 David Bohm expanded on de Broglie’s work to propose the Pilot wave theory. This theory unifies particles and waves as a partnership regardless of what is being observed. Essentially, quantum waves encode physical information, acting as a natural computation device with possible states.
How far can the pilot wave theory go?
Physicists must, however, find a way to separate a surfer from its quantum wave for pilot wave theory to succeed. One method of accomplishing this is to emit two particles and measure each separately. As a result, the second particle's behavior is altered after the empty quantum wave interferes with the wave of the first particle.
Practically speaking, the devices required to detect such an event would need to be extremely sensitive. This isn't outside of the bounds of feasibility, but it is a task patiently waiting for an opportunity. Empty pilot waves might even hold the key for solving practical problems in quantum computation by making the waves less prone to surrounding noise.