What If We Could Shrink To PLANCK LENGTH? | Unveiled
In this video, Unveiled takes a closer look at the Planck length - the smallest length imaginable in physics! What would happen if HUMAN BEINGS were this incredibly small? What would reality look like? And how would we understand life, the universe, and everything?
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What If We Could Shrink to Planck Length?</H4>
In technology, what does true and meaningful progress actually look like? For some, the endgame is a far off dream filled with cosmic-level megastructures, like Dyson Spheres, Shkadov Thrusters, and Matrioshka Brains. But, for others, we should be heading in the opposite direction… toward things that are very small. And we shouldn’t just stop at nano gadgets and machines, either… we should be trying to turn ourselves subatomic.
This is Unveiled, and today we’re answering the extraordinary question; what if we could shrink to Planck length?
Of all contemporary scientific ideas, the field of quantum physics is arguably the one that has really grown in the twenty-first century - and not only thanks to Marvel and Ant-Man. The standard model of particle physics is now fuller than ever before, with many of the world’s greatest minds buried in questions concerning atoms, protons, leptons, and quarks. We know that when we drill down to such a microscopic level, some seriously weird stuff starts to happen, and the apparent laws of physics effectively crumble away. And so, because this is a realm that we still understand so little about, and because quantum science could well hold the key to how basically everything else about reality works, wouldn’t it be great if we - human beings - could physically visit the world of the very small.
While there is some debate as to exactly how accurate it is, the Planck length is generally held to be the smallest length possible, according to physics. It’s a theorized but ultimate base unit, built around the universal constants, and down to which all other units of length can eventually be reduced. It’s a concept that was first introduced in an 1899 paper by the German theoretical physicist, Max Planck, who at the same time suggested a Planck mass, Planck temperature, and Planck time, as well. All of those also represent the smallest of the small. All of the apparently tiniest things you can imagine - from a hair’s breadth to the height of an atom itself - could be described in Planck length measurements. Although even those two seemingly tiny examples are actually many, many times larger. What happens after the Planck length isn’t wholly known… but one theory is that it’s there where black holes and infinite singularities actually form. Where the true breakdown of physics unfolds.
This is much more than simply subatomic, though. Even the largest atoms are multi-trillion trillions of times bigger than the Planck length is. According to most interpretations, the Planck length is smaller than the observable universe is large. The scale involved to reach it is just mind-blowing… and yet, if we were to reach it, we’d have a truly fundamental understanding of what reality actually is. We’d have long since moved past even the trickiest concepts, like quantum entanglement and superposition, that dominate our current studies of quantum mechanics. In truth, there is no comparison that really makes sense… but, for the sake of visualization, it would be as though the universe were a blanket, and the Planck length is the fibers which then get spun into material, which then get sewn together to make the blanket itself.
As such, the Planck length is important in string theory, one of the most well known candidates toward a theory of everything. In string theory, it’s proposed that existence, at its very essence, is made up of vibrating strings that weave together to create… well, everything. It’s hypothesized that these strings are one Planck length long. Seeing as they’re put forward as an effective base substance for everything else, there’s nothing smaller that could combine to create them… therefore, there has to be just a Planck length from one end to the other.
The Planck length (and, indeed, Planck time, mass and temperature) are all important when discussing the beginning of the universe, too. With the leading model, the Big Bang Theory, science can now travel back to mere milliseconds post Big Bang with surprising reliability… but there’s always further that we could go. And, at the extreme beginning, at the true moment when everything started, we’re inescapably dealing in Planck units. If before there was nothing, and then there was something… then the very first parts of that “something” must have existed at the Planck level. This is the briefest of brief times before anything else happens.
One bizarre realization, then, is that if humans really could shrink to Planck length (while still somehow maintaining all the thoughts, functions and feelings that make them human) then all that they’d really experience is total, extreme, and inevitable boredom. Yes, you’d now be operating at the base level of reality, which sounds pretty cool… but endless, absurdly uniformed Planck length units would be all there is for you to comprehend. No variety whatsoever. No action, change, or anything of interest… just constant and maddening sameness. If string theory is true, then you’d have only the strings themselves for company.
The journey down to Planck length would be much more interesting… and a lot more like the various adventures of Marvel’s Ant-Man, DC’s Atom, and all other subatomic superheroes. Move even a tiny fraction up from Planck level and change starts to happen, differing conditions begin to form, and enriching complexities begin to appear. Protons form nuclei; nuclei anchor atoms; atoms make cells and molecules, which in turn inform reality (on our macro level) as to what shape it should take. Moving down to the Planck length, then, is effectively an exercise in dismantling what’s real, and in realizing how different even the seemingly immovable facts of life could be. Water’s only like that because of how it’s structured subatomically; your computer screen only exists thanks to the tiny building blocks that make it; our hearts only keep us alive because of how certain, infinitely small pieces are precisely layered together.
Physicists often speak of the fine-tuning problem, and again Planck units could be key to it. While usually applied to the specific conditions of the universe at large, the fine-tuning problem broadly addresses the seeming unlikelihood for various terms of reality to be precisely as they are - such as the speed of light and the strength of gravity. If this life, this universe, wasn’t exactly like it is… then this life, this universe, wouldn’t be here, so the idea goes. The chances are just so incredibly slim. But, perhaps we can only ever make sense of them if we tap into the very smallest units possible - the Planck length, etc. Only then could we grasp how and why things are as they are.
Of course, shrinking to Planck length will only ever be a hypothetical thought experiment. Technology is improving at a pace, and we’ve never had greater control than now over things like genes, cells, atoms and elements… but there are limits as to how small we can go, even as an outsider looking in. In this way, subatomic study could be seen as very similar to cosmological study. Both fields are forever pushing the boundaries of what’s possible, and we have greatly expanded our knowledge in recent years… but, as with the distinction between the observable and unobservable parts of the universe, it could be that there are some subatomic barriers that are beyond us, too.
Ultimately, the Planck length remains a theoretical unit, at the very end of every other system of measurement that’s ever been devised. It trumps all of them in terms of smallness, but if we were ever to actually get there… there wouldn’t be a great deal to actually see, as a result. And, if you were to move just a little bit further, if you were to fall off the scale completely, then you could well find yourself wrapped up (or warped up) into the formation of an effectively measureless black hole. If string theory is true then you will have proven it along the way… or you might’ve wrought some serious damage to the world’s fine-tuning, by effectively rummaging around inside reality’s insides.
Perhaps it would be better to avoid all that meddling… or maybe it’s worth it in the pursuit of knowledge. But, what’s your verdict? Would you travel to the Planck length if such a thing were possible? Or would you better settle for something a little higher up? For the nano realms of atoms and fundamental particles? Or are you quite satisfied with life as it is, on the everyday scale of regular human beings? Let us know in the comments, but for now… that’s what would happen if we could shrink to Planck length.
