The Higgs Field as the New Ether
What Einstein Said
Friday, July 20, 2012
The Higgs boson has been found!
The Higgs boson has not been found!
What the heck is the Higgs boson, has it really been found, and why should we care?
The Higgs boson is a key particle in the Standard Model of particle physics, which currently stands as our best theory of the very small. The problem is that the theory predicts the presence of the Higgs boson as a necessary ingredient for imparting mass to particles that have mass; and it hadn’t been found after decades of searching.
Particles like electrons and protons have mass. Particles like photons, the quantum of light, don’t have mass. Photons are a type of boson, which are essentially energy particles, as opposed to fermions, which are matter particles. The Higgs boson imparts mass to massive particles like electrons and protons. Or so the theory goes.
Dennis Overbye in the New York Times provides a good analogy: the Higgs boson, and the Higgs field that it creates, is like molasses. As massive particles travel through the field they are slowed down like a spoon pushed through molasses. Without the Higgs field, particles would all travel at the speed of light and have no mass.
So what did the European science team at the Large Hadron Collider (LHC), a multi-billion dollar project completed in 2008, find exactly? Well, UC Santa Barbara physicist Joe Incandela, spokesman for one of the LHC teams, announced that after going through literally trillions of data points, they had uncovered strong evidence of something Higgs-like. This is far from a confident assertion that the Higgs boson has been found, as many outlets erroneously reported. There is still plenty of room for doubt and interpretation.
For many, however, despite the ongoing uncertainties, which will be reduced with additional experiments, the new findings represent an amazing vindication of the power of the human mind and of international collaboration. I agree with these claims but I find the Higgs field discussion very interesting from another perspective: The Higgs field has brought back the notion of an ether.
(Much of the following discussion is adapted from an in-progress book I’m working on).
The ether is generally described, along with things like phlogiston, as one of science’s big screw-ups. We know now, the story goes, that there is no ether. Einstein dispelled this myth, right? Wrong.
Frank Wilczek, a Nobel Prize-winning physicist at MIT, writes in his 2008 book The Lightness of Being: Mass, Ether and the Unification of Forces:
“No presently known form of matter has the right properties [to play the role of the ether]. So we don’t really know what this new material ether is. We know its name: the Higgs condensate [or Higgs field], after Peter Higgs, a Scots physicist who pioneered some of these ideas. The simplest possibility … is that it’s made from one new particle, the so-called Higgs particle. But the [ether] could be a mixture of several materials. … [T]here are good reasons to suspect that a whole new world of particles is ripe for discovery, and that several of them chip in to the cosmic superconductor, a.k.a the Higgs condensate.”
As the title of Wilczek’s book suggests: He argues from many lines of evidence that there is in fact an ether that undergirds space, which he calls alternately the ether, the Grid or the “cosmic superconductor.”
In a little-known tale of 20th Century physics, Einstein himself regretted his 1905 dismissal of the ether as “superfluous,” in his seminal paper on special relativity. Einstein’s own thinking evolved to the point that he realized that some type of (relativistic) ether was theoretically necessary after all. Einstein called this his “new ether,” but changed his terminology over time, as we shall see below.
In 1916, Einstein published his general theory of relativity, which asserted a very different conception of space and time than that put forth in 1905. In general relativity, space has no independent existence; rather, it is a consequence of the various fields that are ontologically fundamental. Shortly after his momentous general relativity paper was published, he exchanged letters with Hendrik Lorentz, the Nobel Prize-winning physicist and one of Einstein’s mentors, on the topic of the ether. Lorentz argued throughout his career that some notion of the ether was necessary for a valid description of reality. Einstein conceded eventually that indeed a non-material ether was necessary to explain inertia and acceleration. Einstein first described his “new ether” in a 1916 letter to Lorentz:
“I agree with you that the general theory of relativity is closer to the ether hypothesis than the special theory. This new ether theory, however, would not violate the principle of relativity, because the state of this … ether would not be that of a rigid body in an independent state of motion, but every state of motion would be a function of position determined by material processes.”
Einstein also wrote in a 1919 letter to Lorentz:
“It would have been more correct if I had limited myself, in my earlier publications, to emphasizing only the non-existence of an ether velocity, instead of arguing the total non-existence of the ether, for I can see that with the word ether we say nothing else than that space has to be viewed as a carrier of physical qualities.”
From 1916 to 1918, Einstein was in the thick of discussions with a number of colleagues about the nature of space and the ether, with respect to general relativity. As Walter Isaacson recounts in his wonderful biography of Einstein, Einstein’s thinking changed dramatically during this period. In 1918, he published a response to critics of special and general relativity. In this dialogue, Einstein writes that the “diseased man” of physics, the “aether,” is in fact alive and well, but that it is a relativistic ether in that no motion may be ascribed to it.
In 1920, Einstein became more emphatic regarding the ether, recognizing explicitly that the ether was a necessary medium by which acceleration and rotation may be judged, independently of any particular frame of reference:
“To deny ether is ultimately to assume that empty space has no physical qualities whatever. The fundamental facts of mechanics do not harmonize with this view… Besides observable objects, another thing, which is not perceptible, must be looked upon as real, to enable acceleration or rotation to be looked upon as something real … The conception of the ether has again acquired an intelligible content, although this content differs widely from that of the ether of the mechanical wave theory of light … According to the general theory of relativity, space is endowed with physical qualities; in this sense, there exists an ether. Space without ether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring- rods and clocks), nor therefore any spacetime intervals in the physical sense.”
Again, Einstein stressed that this new ether was relativistic. Einstein struggled with these ideas for much of his career. As a realist, Einstein argued during the middle and latter parts of his career that physics must attempt to describe what is truly real and not avoid discussion of concepts that cannot be directly detected – such as the ether – even if they seem to be logically necessary due to indirect evidence. So for Einstein, even though the ether was considered undetectable, he deduced its existence because of its effects on observable matter through inertia, acceleration, and rotation.
We are, of course, now at the point where we are starting to find direct evidence, of a sort, for the ether in the form of the Higgs field.
Einstein labored mightily in the 1920s and 1930s to develop a unified field theory that would re-cast all things, including space, as a manifestation of the “total field,” a synonym for his “new ether.” Einstein stated in his 1938 book, The Evolution of Physics: “This word ether has changed its meaning many times in the development of science. … Its story, by no means finished, is continued by the relativity theory.”
Back to the present day, Lawrence Krauss, a well-known physicist and science popularizer, wrote recently of the Higgs field announcements in a way that strongly supports a revival of the ether concept:
“The brash notion predicts an invisible field (the Higgs field) that permeates all of space and suggests that the properties of matter, and the forces that govern our existence, derive from their interaction with what otherwise seems like empty space. Had the magnitude or nature of the Higgs field been different, the properties of the universe would have been different, and we wouldn’t be here to wonder why. Moreover, a Higgs field validates the notion that seemingly empty space may contain the seeds of our existence.”
In sum, the recent evidence regarding the Higgs boson lend support to Einstein’s “new ether” concept and, more generally, to the idea that there is a ground of being that undergirds our reality: the “seeds of our existence,” as Krauss states. This ground of being is apparently not directly detectable but we can infer its presence through many lines of reasoning, including discoveries like the Higgs field, if this data is supported by future experiments.
On a related note, recent evidence of dark energy, a mysterious repulsive energy emanating from ostensibly empty space and thought to be responsible for the accelerating expansion of the universe, may mesh nicely with the “Higgs field as ether” notion. More on this in future essays.
It’s an exciting time to be a physicist – or simply someone who follows physics closely. Actually, it’s a very interesting time to be alive, no matter what one’s interests are.
For a thorough discussion of Einstein’s ideas on the ether, based on primary documents in German, with English translations, see Einstein and the Ether (2000) by Ludwik Kostro.