A wormhole is the one way, in the context of general relativity, that immediate transport between two disparate, disconnected events in spacetime can occur. These “bridges” are mathematical curiosities only at this point in time; no physical wormholes have ever been found to exist or have ever been created, but if one were discovered it could immediately test general relativity’s predictions, as well as any alternative competitors. (Credit: vchalup / Adobe Stock)
Relativity and the physics of immortality
Nothing lives forever, at least, not in the physical Universe. But relativity allows us to get closer than ever, from one perspective.
Ethan Siegel
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Published in
Starts With A Bang!
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11 min read
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1 day ago
From your own experiential perspective, the laws of physics are stacked against you if you ever hope to achieve immortality. From a thermodynamic perspective, every system tends towards increasing entropy-and-disorder, and the only way you can combat that is by constantly inputting an external source of energy; in other words, your body and mind will eventually break down. And although you might try and leverage the power of relativity to dilate time and slow its passage, that will never work from your individual perspective; time only dilates or slows relative to an observer in a different reference frame from your own.
While this may confine a human’s dream of immortality to solutions that rely on technological enhancements or science-fiction level technology that relies on novel physical laws and/or phenomena, there’s still plenty for relativity to say about living forever: at least, relative to the rest of the Universe. While nearly all of us living today will certainly be dead in another century, should we all remain on Earth, the lessons from both special and general relativity teach us that there are a few physical situations that we should strive for if we truly want to maximize the amount of time that we can spend as living creatures within our Universe. Here’s the key insight we all need to understand.
This moving, zipping star field appears to depict an ultra-relativistic motion through space, extremely close to the speed of light. Under the laws of relativity, you neither reach nor exceed the speed of light if you’re made of matter. You might be able to approach it if you had a large-enough amount of an efficient-enough fuel, but you still need to obey the rules of relativity. (Credit: Jahobr/Nevadawest of Wikimedia Commons)
The foundation of relativity: spacetime
Even though we normally credit Einstein with overcoming the disparate ideas of space and time that had held sway since the time of Newton and coming up with the revolutionary concept of a four-dimensional fabric that weaves them both together — spacetime — it wasn’t Einstein at all that came up with that key insight. It’s true that 1905 was indeed a banner year for Einstein, with the two key insights that powered special relativity key among them:
- That the laws of physics are invariant, or that they do not change, in…
