What If Gravity Slowly Disappeared? | Unveiled

What If Gravity Slowly Disappeared?

Even in uncertain times, if there’s one thing we can be sure about, it’s gravity. But what would happen if this fundamental force suddenly wasn’t so reliable?

This is Unveiled, and today we’re answering the extraordinary question; what if gravity slowly disappeared?

Most of us have a general idea about what gravity is. It’s the natural phenomenon which draws things toward one another. On Earth, gravity is what keeps our feet on the ground; it’s what ensures that we don’t just float off into space. In the solar system, it guides the planets to move around as they do; with everything gravitationally bound to the closest object with the most mass, usually the sun. In the universe, gravity does the same job again; tying everything to everything else, and shaping how the entire cosmos is structured - from the tiniest speck of dust to whole, sprawling galaxies.

Is it something which could ever be turned off? Or that we could ever run out of? In the real world, no it isn’t. For as long as there are objects with mass at varying distances away from each other, there will always be gravity (and the effects of). And, seeing as it’s generally accepted that the universe isn’t losing mass, gravity isn’t going anywhere. In an alternate world, though, where gravity is more of a measurable, manageable substance, the idea that it could disappear would rock every single aspect of our reality.

First and foremost, we’d be living in the midst of a countdown to the end of the universe. Or, at least toward the totality of chaos. No gravity means no order, structure or predictability in space, and the chances of anything surviving at that point would be absurdly low. Still, if gravity were disappearing at a slow enough rate, the knowledge of an unavoidable doom in the future needn’t change all that much about how we thought and behaved in the present. Today, we know that the sun will (in about five billion years’ time) expand into a red giant, and possibly devour Earth while doing so. And, even if it doesn’t swell quite large enough to consume our planet, we know that the prospects of life surviving on Earth at this point in the future are basically zero. But that doesn’t mean that we’re all walking around dreading the day the sun blows. Most of us don’t even think about it. It’s so far in the future, and so far beyond our own lifetimes, that it doesn’t really seem to matter. If gravity were slowly disappearing, but we knew we were safe for at least a few billion years more, then we’d probably adopt a similar view.

If gravity were disappearing but at a faster rate, however, it would begin to impact our daily lives. Arguably the closest thing we have in the real world to a situation like this is the doomsday clock, particularly in relation to global warming. The doomsday clock was created in 1947 as a means to assess the various threats facing humanity. Over the years, it has been pushed forward or back thanks to a number of things, including the threat of nuclear war and climate change. In January 2020, the clock was pushed as close to midnight as it has ever been, with just one minute forty (or one hundred seconds) left to run. Now imagine a construct like this, only it measures how much gravity we’ve got left to use. Such a thing would work like a fuel gauge for the planet, and we’d be nervously eyeing the red zone… where we’d have reached a gravity tipping point; a point of no return.

Just to reiterate, this is a totally, incontestably hypothetical reality. It isn’t about to happen. But, if it was happening, and just on Earth, what would it actually mean for our planet. It would most likely mean that Earth was in some way losing mass, and that loss of mass would probably be the easiest way for us to quantify the loss of gravity - to run something like a gravity clock. We’d need to have a more detailed understanding of our planet’s makeup than ever before, but we’d also have to view our planet as though it were grains of sand inevitably falling through our fingers… we’d know that life on Earth really couldn’t last forever.

What sets this scenario apart, however, is the slowness of the change. This isn’t an on/off switch for gravity, it’s gravity trickling at a steady rate down the drain. Which means that, over time, we could expect evolution to put up a least a little bit of a fight. Even as we are, gravity has helped to shape what life is; what it looks like and how it behaves. Unlike other aspects like climate and environment, the gravitational influence on Earth has been a constant since the planet formed… and has always been there while life has moved from single-celled organisms to many-celled, complex creatures. As such, we know that changes to that gravitational constant can cause problems - most easily seen with astronauts who experience microgravity.

Among the ailments listed during and after a long spell off-Earth in a low-g environment are; muscle atrophy, a decrease in bone density, cardiovascular problems, hand-eye coordination problems, and fatigue. Because gravity even guides how fluids are passed around the body, a loss of gravity can also be linked to things like vision impairment, a puffy face and sinus problems, back pain and even kidney stones. If gravity were slowly disappearing as just a fact of life, however, and if the disappearance was happening slow enough, we might expect the human body (and life in general) to adapt to account for these changes. Even with plants, gravity is key to how they grow, with gravitropism being the term used to describe how roots and stems are separately bent and shaped in relation to gravity. But, if it were slowly disappearing then this would change, too, meaning entire landscapes would gradually transform to look very different.

It wouldn’t all be about the natural changes, though. In a world advanced enough to 1) know it was losing gravity and 2) be able to measure that loss, you can bet there’d be a wealth of tech and lifestyle changes needed to counterbalance the situation. Most vehicles - from cars to cruise ships and planes - would need regular redesigns to ensure they remained safe and efficient. The infrastructure in towns and cities would need constant tweaking to prevent breakages over time. And the manufacturing of artificial (or replacement) gravity would probably be the biggest business on Earth. Today, models to create artificial gravity are put forward as possible far-future solutions for life away from Earth… but now we’d need those solutions on the planet itself. And we’d probably need them at a much smaller scale. Sci-fi-style centrifuges are great, but we’d now need technicians and inventors to condense it all down to somehow fit inside something like a shoe or backpack, to keep an individual person or thing on the ground. Not easy, probably not even possible.

And, ultimately, in an alternate world where gravity itself was running out anyway, then anything we tried would only amount to a temporary fix. And the endgame isn’t pretty. By the time we reach absolute zero gravity, we (humans) will’ve long gone. We’d be a species literally pulled apart over the years. Meanwhile, the rest of the world would’ve changed over time, too. Without gravity to tie them down, our rivers, lakes and oceans will’ve slowly drifted off into space. As will’ve sand. And then small rocks. And then larger rocks. Plants will’ve slipped out of the soil that would also be floating apart. Eventually, without gravity, all chunks of matter would break down… meaning no planet, no Earth, at all. Away from Earth, the outlook for everything else is just as bleak. The sun would break apart, too, as the solar system descends into a dusty, soupy mess. And the rest of the entire universe would suffer the same fate - breaking apart into smaller and smaller pieces. Our doomsday gravity clock from earlier will’ve definitely struck midnight. Total ruin would be upon us.

It’s lucky, then, that this is one hypothetical reality that really can’t happen. There’s much in life that we can’t rely on, but we can rely on gravity. Since the dawn of the cosmos, it has been steering and shaping the universe toward what it is today. And it’ll continue doing that, exerting its truly fundamental influence, until as far into the future as you can imagine. But that’s what would happen if gravity slowly disappeared.