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.