They laughed at the Wright brothers !
This past week, I saw a short note on the PhysOrg Web site on the problem of dark matter. Briefly stated, the problem is that, in order to account for the gravitational force we observe acting on objects in the universe, the universe would need to have about twenty times as much matter (mass) in it as we are actually able to see. Put another way, the observable mass of the universe only accounts for about 5% of the observed gravity. The current consensus idea among physicists is that “dark matter” accounts for the difference:
The conventional explanation is that enormous amounts of invisible dark matter make up the missing 95 per cent but some have argued that it’s Einstein’s theory that’s at fault.
A review article in this week’s issue of Science talks about some of the ideas that have been tried, as an alternative to dark matter, to explain the effect. None of these seems to be terribly satisfactory; what they gain on one hand by eliminating the need for dark matter, they tend to take away with the other by introducing “dark fields” that influence the structure of space-time.
I’m certainly not qualified to evaluate the theoretical physics at issue, but it seems to me that all of this most likely indicates that there is just a piece of the puzzle we haven’t found yet.
I was reminded of this by another article, in Ars Technica, about the role of “fringe” theories in science, those proposed theories that are well outside the mainstream of scientific thinking at the time. The article makes the excellent and valid point that there are some very notable, and currently widely accepted, theories that initially were greeted with skepticism and even hostility. The classic example is the theory of plate tectonics, developed by Alfred Wegener:
Some truly revolutionary scientific theories may take years or decades to win general acceptance among scientists. This is certainly true of plate tectonics, one of the most important and far-ranging geological theories of all time; when first proposed, it was ridiculed, but steadily accumulating evidence finally prompted its acceptance, with immense consequences for geology, geophysics, oceanography, and paleontology.
But for every theory like plate tectonics, there are dozens of theories that are greeted with great, and ultimately entirely justified, skepticism. Of course the progress of science depends on the willingness to entertain new ideas, but not at the expense of jettisoning one’s critical faculties. As Richard Feynman once put it, scientists need to “Keep an open mind, but not so open that your brain falls out.”
Perhaps due to fictional portrayals of lone scientists bravely struggling for truth, people sometimes have an over-romanticized notion of the role of the lone scientific hero. The reality is that, usually, the scientific consensus is more or less on the right track. Even true breakthroughs, like those of Newton or Einstein, were consistent with the important work being done in their field — they were in a sense works of synthesis. One should generally be skeptical of any claim of entirely new insight (especially if it scores high on the delightful Crackpot Index).
Yes, they laughed at the Wright Brothers — but remember, they laughed at the Marx Brothers, too.