Famed cosmologist and modern-day genius archetypein Cambridge, England, at the age of 76.
But if Hawking's intuitive understanding of quantum mechanics is correct, he's also still alive somewhere. Actually, he's probably still living in a number of places beyond this universe.
Hawking was an ardent supporter of the notion that there could be not just one universe, but perhaps an infinite number of universes. If that idea is literally true, then somewhere in another dimension of what some might call the multiverse, there's a world almost exactly like this one, except that Stephen Hawking is still with us and still trying to sort out a grand theory that explains the totality of existence.
There could also be alternate universes with completely different laws of physics, or one where life failed to ever pop into existence, with no Stephen Hawking there to attempt to explain its weirdness.
But right now the alternate universe that feels most painful to imagine is the one where Hawking was never stricken with ALS. The universe where a confident and able-bodied Hawking might still have a few more decades left to stride across stages around the globe, explaining everything and bantering with audiences in real time. In recent years, Hawking would often receive interview questions well in advance to prepare and give his answers via his familiar speech synthesizer.
Many of the concepts that Hawking put forward or that carry his name, like the Hawking radiation believed to be emitted by black holes, can be hard to grasp for lay people. For most of us, it's even harder to find a reason to care about such abstruse things in the context of daily life on planet Earth, safely located many, many light years away from the nearest black hole.
But Hawking's individual works were all part of his life's work to crack the code of reality itself with a unified theory of everything. Despite being unable to physically move himself for decades, Hawking intuited and calculated connections between the quantum mechanics that governs the rules of the universe at its smallest and most bizarre scale, to the vastly different but still unfathomable cosmic scale where Einstein's rules of relativity explain how gravity can bend space-time itself.
Hawking's powerful brain, housed in a broken body, seemed to be a key that could unlock doors to understanding the weird worlds that define our existence yet remain largely inaccessible to most of us. And somewhere along the way, Hawking also made it his mission to make more accessible to others the understanding that seemed to come so easily to him.
In 1988 he published "A Brief History of Time," which became a bestseller, and he soon became a widely recognized public figure.
He could not move himself across a room under his own power, but it was no matter. For the past three decades or longer, the media has been the vehicle. Whether explaining the idea of multiple universes, or launching an effort to , Hawking was a motivating force. His name has been all the fuel needed to push an idea out into the universe, riding on radio waves at the speed of light.
There's an idea out there in science fiction, including the, that suggests some black holes could be portals to other universes, sometimes referred to as wormholes. It may like a lazy way to advance a convoluted and fantastical narrative, but it's one that Hawking himself would not dismiss.
"The hole would need to be large, and if it was rotating, it might have a passage to another universe," Hawking said in a 2008 lecture. "Black holes ain't as black as they are painted. They are not the eternal prisons they were once thought. Things can get out of a black hole, both to the outside, and possibly, to another universe. So, if you feel you are in a black hole, don't give up. There's a way out."
Right now it feels as if Hawking has been lost forever into another mysterious black hole, the one at the end of life that slowly pulls all of us toward it. Hawking didn't believe that the black hole we know as death was a portal to another universe, to a place where he might finally get to meet the creator of all that he labored to understand. He famously considered the notion of God to be "unnecessary."
But if existence is the way Hawking believed it could be, then somewhere there's an alternate Hawking in another universe not just striding across stages, but perhaps also sailing through black holes, navigating multiple universes and dimensions. Maybe one day that Hawking will even manage to pay us a visit.
Until that day, we'll remember a man who overcame almost unfathomable physical challenges to broaden humanity's horizons in ways we're just beginning to comprehend.
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