After the "Science" March, We Will Do Some Science

Many of the folks who participated in the science march this weekend seem to have a view of science seem to have a definition of science that involves a lot of appeals to authority and creation of heretics.  Unfortunately, the video below relies on the old-fashioned cis-gendered white male definition of science, which involves using theory to establish hypotheses which are confirmed or denied through observation.  In this dated definition, there is no such thing as heresy in science.

Let me tell one of my favorite stories about scientific consensus.

Perhaps the most important experiment of the last 150 years was Michelson and Morley's interferometer study trying to measure the aether drift.  What is this?  Think of bullets fired from a moving airplane.  From the perspective of someone standing on the ground, bullets will initially travel much faster when fired forward rather than backwards, as the velocity of the plane is added (or subtracted) from the velocity with which they leave the gun.  Everyone, and I mean virtually everyone in the scientific community (WAY more than 97%) assumed the same happened with light.  M&M's hypothesis in their experiment was that light "fired" in one direction will travel at a different speed than light fired at a 90 degree angle to that, due to the Earth's movement through the universe, filled with some sort of aether (yet another of a long line of imponderable fluids proposed to explain various physical phenomena).   They found no such difference -- the speed of light was identical in every direction.   M&M has been called the most important negative result in the history of science.  Einstein and special relatively explained the result a few years later.

While we are on the topic, I want to mention something that always makes me crazy when you see popular articles about Einstein.  You will frequently see stories about Einstein being turned down for a promotion at the patent office or turned down for a teaching job or that he got bad grades.  The point of these stories is always something like, "ha, ha look how stupid these other folks were to give bad grades to the greatest mind of the 20th century."  But Einstein was never a great mathematician.  One always hears that relativity involves all this crazy math, and that is true for the later general relativity, but one can derive the basic equations for special relativity using nothing more than algebra and the Pythagorean theorem.  Seriously, I had to do it on a test when I was 17, it is not that hard.  Perhaps I will show it in a post one day if I am really bored.  Later, better mathematicians wrote papers cleaning up the math of special relativity and making it more robust, and later Einstein had to get a LOT of help with the non-Euclidean geometry involved in general relativity.

I believe (and this is a personal conclusion from reading a lot about him and not necessarily a widely held belief) that a lot of Einstein's greatness came from the fact that he had the mind of a rebel.  He was willing to consider things the science establishment simply would not consider.  It is STILL hard, even a hundred years later, for many of us laymen to accept that time is somehow non-absolute, that it changes depending on one's frame of reference -- so imagine how hard it was for someone in Einstein's time.  In the 19th century, the world of physics had become split into two worlds that folks had come to think of as incompatible and separate -- the world of physical objects governed by Newtonian physics, and the world of light and waves governed by Maxwell's equations.   Maxwell's equations implied light always had a fixed speed.  Everyone assumed this had to be fixed vs. some frame of reference.  The assumption of an aether or fixed point of reference against which light's speed was fixed was the 19th century solution for uniting these two worlds, but M&M demolished this.  It seemed that light had to be a fixed speed in every direction and every frame of reference.  Eek! Einstein asked himself how to explain this result, and thereby re-united Newtonian and wave physics, and he concluded the only way to do so was if time was variable, so he ran with that.  That is not an act of math, that is an act of a flexible, rebellious mind. And flexible rebellious minds do not do very well in schools and patent office bureaucracies.



  1. Dan Wendlick:

    there are alternative explanations of the M&M experiment null result. One is that the Earth is the immobile center of the universe, which Newtonian physics effectively rules out, although with enough epicycles....

    Maxwell's equations imply that at a particular velocity a wave that has an electrical component normal to a magnetic component will be self-inducing. There was a lot of critical work that demonstrated that this wave was what we considered to be light. A guy by the name of Lorentz noted that with a particular coordinate substitution, you could convert between inertial reference frames and make this propagation velocity invariant, but missed the implications of this as he still held onto a notion of invariant time.

    Einstein's insight was that if you applied the Lorentz transform such that one of the inertial frames of reference was tied to a point on the Maxwellian self-inducing wave, you could no longer keep the idea of a fixed event time in all frames of reference, and thus Time itself was variable in a 4-dimensional space. Thus came Special Relativity

  2. Michael Morley:

    Not that this disrupts your main thesis, but Einstein did in fact do quite well at mathematics in school. This misconception appears to have arisen because of a reversal in how grades were recorded, from low numbers being better to low numbers being worse. (No idea where I heard this in the first place, but searching quickly finds this

  3. antognini:

    It's also important to remember that although we tend to assign enormous importance to individual experiments in retrospect, the strength of these revolutionary experiments comes from a large body of lesser-known work that supports the more famous experiment. In the case of the Michelson-Morley experiment, there were dozens of other similar experiments performed both before and afterwards. (In fact, similar experiments were being repeated throughout the twentieth century, and there continue to be modern day experiments to test Lorentz invariance.) The Michelson-Morley experiment was uniquely precise and came at an opportune moment, but if it had been the only result of its kind, it probably would have been dismissed as an anomaly.

  4. smilerz:

    If I find myself in an argument about how skeptics or Republicans are anti-science in regards to climate change I'm going to start asking questions about minimum wage and rent controls.

    Interesting insight into Einstein BTW.

  5. Nehemiah:

    Mach's equations showed that the earth could be at or near the center of the universe (center of mass).

    It was thought that the Michelson - Morley experiment would yield results showing the Earth
    moving through the aether at orbital speeds (30k/s). The result was way
    off the mark recording a "Null" result (insignificant relative to the expected result). Although Michelson & Morley derived a "Null" result, they did record a small deviation in the response time of the two beams. This was thought to be the result of partial aether drag approximately equivalent to the rotational speed of the Earth. But this was a huge problem in that on the one hand there was no measurement recorded for the orbital speed of the Earth while on the other hand there was a measurement approximating the rotation speed of the Earth.

    25 years later Michelson teamed up with Henry Gale to run additional experiments with much improved equipment. Once again the measurement did not pickup orbital speed, but did record the rotational speed to 98% accuracy.

    Between Michelson's experiments, Georges Sagnac conducted experiments that seem to confirm the rotational aether drift. Our Global Positioning System incorporates an adjustment to compensate for the Sagnac effect (aether drift).

    If you want to explore the controversy further follow this link

  6. Nehemiah:

    Here is a research paper concerning Newton's field equations and Mach's principle regarding mass.


  7. markm:

    For example, a series of astronomical observations disproved the hypothesis that (as Warren phrased it) light behaves like bullets. If the velocity of light added to the velocity of the source, light from the inner satellites of Jupiter would be delayed or advanced by several seconds, depending on whether the satellite in its orbit was coming towards us or going away. This would affect the times at which various conjunctions would be observed, but no such timing shifts existed.

    So if the velocity of light did not depend on the source, what did control it? The ether hypothesis, that light was waves in some sort of insubstantial substrate, was brought into play to suggest that the ether provided a fixed 0-velocity reference in the universe - after other astronomical observations disproved the hypothesis that ether could be dragged along with planets and moons, which would imply a velocity change going from the vicinity of a light source out into interplanetary space. So the final hypothesis that wasn't unimaginably weird was that light moved at 'c' with respect to a fixed point in interstellar space, and so measurements on Earth would show a difference depending on whether the light was traveling along Earth's orbit, or across it. MM showed that light speed was constant even then. It didn't depend on the velocity of the source. It didn't depend on the velocity of the receiver. It _was_ unimaginably weird.

    Einstein could imagine it...