Science is, ideally, a self-correcting enterprise. Built into the very framework of the evidence-based model of scientific inquiry, whether it be experimental or observational evidence, is the idea that all scientific ideas are tentative, to the degree that a really good idea can be amended (or even completely overthrown) by new evidence that contradicts the scientific model.
This means that the history of science is littered with failed hypotheses ... some of them quite ingenious ones, which were held onto by scientists for quite some time.
Consider, for example, the notion that the universe on cosmological scales was eternal and unchanging, a concept which took pretty firm hold with the work of Aristotle (not that he originated the idea ... please don't send letters!). Though this concept had to be modified a bit when Copernicus pushed the heliocentric model, Galileo Galilei discovered moons around other planets, and Sir Isaac Newton realized that heavenly bodies were moved by the same law of gravity that governed matter on Earth, the concept of a fundamentally eternal cosmos still held such significant sway that Albert Einstein felt the need to tailor his equations to create a cosmological constant explicitly for the purposes of maintaining a static universe.
Today, it is hard to think of a more antiquated scientific picture than the idea that our universe has existed in its current state for all of eternity.
It is unrealistic to believe that everything science believes today will continue to be believed into the future ... and I frankly know of no scientist (except perhaps Sheldon Cooper) who believes such a thing. New evidence will cause scientists to revise the thinking and models, and the understanding of reality will shift accordingly. This is as it should be.
But which current assumptions or theories are, here and now, most ready to be retired?
That's the question posed by this year's "annual question" over at Edge.org. You can find the responses from the 176 respondents - amazing intellects from all over science and academia - over at the website, and they are all extremely fascinating. Here are a few particularly relevant to physics:
- Sean Carroll discusses how the notion of falsifiability as a criteria for scientific status is an idea that needs to be dismissed, along with a great historical analysis of the concept itself, the context in which philosopher of science Karl Popper introduced it, and why it is no longer helpful.
- Andre Linde presents the idea that our universe is neither unique nor uniform, two ideas that are still assumed in much of our scientific thinking.
- Max Tegmark argues against the concept of infinity ... despite the fact that he was "seduced by infinity at an early age."
- Freeman Dyson suggests retirement of the concept of the collapse of the quantum wavefunction, because this concept is usually invoked in a way that gives the impression that the quantum wavefunction is itself a physical object.
- Lee Smolin offers that physicists need to move beyond the idea that the moment of the big bang was the first moment of time, trying to develop cosmological theories that incorporate a pre-big bang period in hopes of making progress in areas where we are currently stifled.
- Lawrence Krauss wants physicists to abandon the idea that the laws of physics are predetermined, and recognize that there exists not a single "one true theory" that nature is compelled to follow, but rather a range of possible physical laws ... some of which actually apply to our universe and to the region of our universe in which we exist (and can observe).
Again, I do really recommend that you read through these responses yourself. Though I'm inclined to be most interested in the ones related to physics, honestly some which fascinate me the most are the ones that offer to transform our assumptions not about physical reality but instead about human nature. As much as physicists sometimes can make jokes about the "squishy" sciences, on this list I've got to admit that the biologists and neuroscientists have some truly fantastic assumptions about being human that I'd like to see be abandoned ...
In the weeks to come, though, I will be returning to this list again and again, discussing some of the physics-related suggestions, the merits to them, and discussing where some of these assumptions came from and why we should keep them (if I can come up with such an argument).
Note: In the interest of fairness, I should point out that the psychologist Alex Holcombe's response for a scientific idea to be retired is, in fact, the very concept that science is self-correcting. While I agree with his many challenges to the self-correcting systems in science, I don't agree it's ready to be retired (or perhaps I just hope it's not).