Zero-Point Energy and Ether
Date: Winter 2013-14
If zero-point energy pervades the entire universe, could it be a candidate or substitute for the so-called "aluminiferous ether" that physicists a century ago believed to exist?
Not really, because the definition of the terms of "zero point energy" and "aluminiferous etherâ" are different. "Zero point energy" arises from the quantum mechanical description of a system. Specifically, it arises from the Uncertainty Principle that states that in any bound system: Î”P * Î” X â‰³ Ä§ where P is the momentum, X is the position and Ä§ is h / 2Ï€ where hbar is Plank's constant / 2 pi. This is strictly a quantum mechanical result.
The aluminiferous ether is an invention to account for the belief that light waves had to have a medium through which light must travel. Since (it was believed) a traveling wave had to have some medium through which to travel. For light this model turned out to not be true. Light could travel without having a medium through which to oscillate. Many subsequent studies supported that the aluminiferous ether did not exist.
For example, the speed of light should be different depending upon which direction the beam is projected. Experimentally it turned out not to be true. It turns out that the model for the propagation of light was incorrect.
The properties of the luminerous aether (a rigid, yet fluidic matrix
to mechanically propagate electromagnetic waves) are a completely
different than those of zero-point energy (the minimum energy level in
a quantum system). Other than the temptation to imagine both existing
throughout the universe, I am having a hard time drawing many
Hope this helps,
The theory of an ether existing in the background stems from the idea that it was needed in order to conduct light (or other electromagnetic waves) through space in a similar manner to acoustic waves being conducted through the vibration of molecules. Einstein threw out that concept and determined what the consequences were. Given that the predictions of his resulting theory (Relativity) have been repeatedly confirmed shows that there is no need for an ether. Further, you can make an argument that one should not exist because if it did, then there would exist a background ether that would provide a reference "velocity" against which you could measure your own velocity. If light conducts within this ether, shouldn't the ether drag it along in this preferred direction? The Michelson-Morley experiment, which has been repeatedly verified) says no.
The problem with the ether theory is that it somehow carries light along but at the same time is essentially immeasurable using light. In other words, it does not interact with light, but light causes ether to vibrate. It would be a strange material indeed. One reason that ether is attractive is that Maxwell's equations, the equations governing light, predict waves propagating in space. It seemed counter-intuitive that nothing is there to vibrate and conduct the wave along. However, if you think about it, a rock moving in space does not need anything to conduct it through space. It simply moves through empty space. We consider this obvious because matter is "solid." Einstein showed, however, that energy and mass are equivalent, so why is it a stretch to think that energy moves through space on its own? Indeed, if you look at Maxwell's equations, they show that the electric and magnetic fields of a wave are self-generating in the sense that the wave front in the present creates a wave front slightly farther in space each increment forward in time traveling at the speed of light. Acoustics, while having similar equations describe them, is based on molecules vibrating. The "ether" for acoustics is built into the equations from the beginning.
Now, you may still have some wiggle room in your proposition, however. Relativity is an extension of classical physics. As he developed Relativity, Einstein was able to bring in the effects of gravity. At the same time as he was developing his theories, Quantum Mechanics was developed and eventually led to the idea of a vacuum that is not empty. To date, the idea of an ether has not needed to be resurrected. However, gravity and Quantum Mechanics have not been successfully integrated into a "grand unified" theory, and if it does happen, we do not know exactly the form it would take. Would an ether have to make a reappearance? It is likely that scientists would resist that notion unless it became difficult to explain a physical effect without it. My sense is that the ether is a comfortable notion to have, but that it will not be needed.
Kyle J. Bunch, PhD, PE
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Update: November 2011