The most fashionable idea-du-jour may be the multiverse. It’s actually an old quantum notion from a century ago, with physical support on the atomic scale, that everything that can happen does happen. Extrapolating to our macrocosmic level leads to an almost infinite number of universes, of which we can only be aware of the one in which we exist.
And already there’s trouble. Because an infinite number of universes, where anything that can happen does happen, means that if you stop at a crossing and turn right, the fact that you could have turned left creates another reality of the multiverse, another version of you that does indeed turn left. Their life with its resulting complexities continues with all the consequences of having performed that alternative action.
And that’s still not the end of it, because an infinite number is greater than merely all possibilities materializing. It means there are multiple identical copies of yourself, along with billions of others that each possess a tiny distinction. One of the other you’s has 18 freckles on their shoulder instead of the 17 that are on yours. And this is not just possible, but inevitable.
The multiverse illustrates a valid recurring issue: How much credence should we give to each science-sounding idea? What about the Dyson sphere? That’s the notion that a civilization could produce unlimited energy if they harvested 100% of a star’s power. You’d do this by constructing an unbelievably vast spherical enclosure around a star so that all of its energy would strike it and be gathered up. These days one even sees purportedly serious articles in science publications speculating whether some distant star’s oddly fluctuating light might be caused by a nearby alien civilization partially completing a Dyson sphere.
Yet another fashionable recurring theme involves colonizating Mars, and trying to solve one or another of the endless technological challenges.
What should be obvious is that imagining something doesn’t mean it’s remotely likely to ever happen. The Martian nonstop radiation, its absence of air and things like medical facilities, the billion-dollar costs of every arriving craft, and the insuperable aerodynamic stresses of the super-high re-entry speed from interplanetary missions, which we’ve yet to ever accomplish, and dozens of other known and unknown hazards and costs, is largely unaccompanied by analytical realism.
We’ve yet to see a sober scrutiny, such as asking why it would make more sense to try to live in Martian crevices or beneath some asteroid’s surface rather than inhabit Earth’s own subterranean regions at one-millionth the cost and at a fraction of the hazards. Or speculate about who would ever pay for such an enterprise. Remember, we’re not talking about a Martian landing by astronauts, which is doable and probably inevitable. This is about colonization, a different animal altogether.
Many noted astrophysicists from Richard Feynman to Carl Sagan have stated unequivocally that we will never colonize Mars because of the dangers, or construct a Dyson sphere due to the cost, which would be greater than building a hundred million Great Walls of China. Simply put, since the Dyson goal is to harvest vast amounts of energy, wouldn’t there be vastly easier methods than building a structure far larger than our entire planet Earth? Why does that idea even deserve repetition?
So back to the multiverse with its infinite parallel universes. It’s something we have conceived. And who knows, it may be possible. But it would be so profligate in terms of redundancy, so tedious in terms of rubber-stamping countless near-identical entities on every biological and physical level, and, philosophically, so in violation of Nature’s seeming leitmotif of fresh creative experimentation, it — like so many other of our mental gymnastics – just doesn’t pass the smell test. At least, not to this observer.
Which leads to today’s Big Question: Whether the human imagination is truly up to the task of pondering the unknown. It takes us back to British geneticist John Haldane who famously said, “The universe is not only stranger than we imagine; it is stranger than we can imagine.”
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