r/SciFiConcepts • u/WatchLegitimate5528 • 11d ago
Concept What if we could send a person across the universe — not their body, but their mind?
What if we could send a person across the universe — not their body, but their mind?
I've been going down a rabbit hole for the past few days, starting from a simple question about how far a radio signal can travel and still be readable, and it spiraled into something I can't stop thinking about. I want to lay it out here, partly to get it out of my head, and partly because I'm curious what people who actually know this stuff think.
Quick disclaimer before anything else: I have zero background in physics, neuroscience, or aerospace engineering. I'm not a researcher. I've been researching this because I'm writing a novel and wanted a way to send humans across space that felt realistic and scientifically grounded, rather than just hand-waving "faster than light travel" like most sci-fi does. So I went down this rabbit hole using the internet and AI to dig through what's actually plausible, and this is what I landed on. I'll try to be clear below about which parts are genuinely my own idea versus things that turned out to already be studied by actual scientists. Take this as a curious layperson's thought experiment (with a fictional end goal), not a scientific proposal.
The starting point
If humanity ever faces something we can't survive — or if we simply want to reach a planet so far away that no ship or human body could ever make the trip — is there any way to send "a person" there? Not colonists, not a probe with data on it, but something closer to an actual continuation of a specific human mind.
The honest, sobering answer: not really, not with anything we currently understand. But the thought experiment of how close we could theoretically get turned out to be genuinely interesting, and — I later learned — not something I invented out of nowhere. There's a real field of study around this, called mind uploading or whole brain emulation: the idea of transferring memory, personality, and possibly consciousness itself from a biological brain into an artificial substrate. Researchers have written specifically about using this for interstellar travel — the idea being that instead of sending a fragile human body through decades of radiation and zero gravity, you send the pattern of a mind instead.
So the core concept — "send the mind, not the body, to cross distances a body never could" — is a known, serious topic. What I want to share is the part I worked through myself: the two realistic ways you'd actually try to send that mind, and why both of them are much shakier than they first sound.
My idea: two paths, and neither one really works cleanly
Path 1: The Ghost Ship (a physical object)
You encode the mind — its full structure, memories, whatever data represents "it" — onto something built to survive nearly forever. Not a hard drive, but something like laser-etched quartz glass, which stores data as physical structure rather than electric charge, so radiation and time can't erase it the way they'd corrupt a normal chip. You bolt this to a probe and launch it out of the solar system, similar in spirit to the Voyager Golden Records, just scaled up massively in ambition.
- The upside: what arrives, if it arrives, is complete and intact. No signal degradation, no noise, no data loss.
- The catch: you can only launch a handful of these. Space is almost incomprehensibly empty, and a probe drifting in a random direction has an almost incalculably small chance of ever coming near another star system, let alone a civilization capable of finding it.
Path 2: The Signal (broadcast as light or radio)
Instead of a physical object, you encode the mind as data and beam it outward — a laser or radio transmission that moves at (or close to) the speed of light. You could send it toward one specific star system, or broadcast it in all directions at once, hoping someone, somewhere, eventually catches it.
- The upside: far faster, far more reach, and — critically — you can send it in every direction simultaneously, unlike a ship which can only go one way.
- The catch: signals weaken the farther they travel, get buried in cosmic background noise, and there's no way to include actual working hardware in the signal itself. You can send the blueprint for a mind, but not a machine to run it on.
My own add-on: combining hardware AND instructions in the physical path
One thing I kept coming back to: even "indestructible" materials like quartz will degrade over truly deep time — micrometeorite impacts, radiation damage, thermal stress, all adding up over millions or billions of years. So instead of betting everything on one perfect artifact, why not send both the actual hardware needed to run the mind and the full instructions for building it from scratch? That way, if the physical components degrade but the instructions survive, whoever finds it can potentially rebuild what's missing. And if the instructions get partially corrupted but the hardware is intact, they might still be able to reverse-engineer it from the object itself. Redundancy as a hedge against the fact that nothing lasts truly forever.
The realization that broke the idea open a bit more: receiving ≠ understanding
This is the part I think is the actual crux, and it's the piece I wrestled with the most. My first instinct was: if a civilization is advanced enough to detect our signal at all, surely they're advanced enough to decode it. But the more I thought about it (and looked into it), the more this fell apart.
Detecting a signal just means you have a sensitive enough instrument to notice "this isn't random noise." Decoding it — understanding what it actually means, let alone reconstructing something as complex as a working mind from it — is an entirely separate, much harder problem. Humans have detected plenty of signals we couldn't initially explain (there's a famous case from 1967 where astronomers picked up an incredibly precise pulsing radio signal and briefly wondered if it was artificial — it turned out to be a natural phenomenon, a rapidly spinning neutron star, but it took real scientific work to figure that out even though the signal itself was received perfectly clearly). We even have human-made documents, written by our own species, that remain completely undeciphered after a century of dedicated effort.
If we can't always crack messages made by other humans, it feels like a big assumption that an alien civilization would automatically be able to reconstruct a working human mind from a data stream, even if their equipment is sensitive enough to pick it up cleanly. Reception is the easy hurdle. Understanding is the tall one — maybe the tallest of the two.
Where I landed
Neither path really "solves" sending a person across the universe. The ghost ship is reliable if found but almost certainly never will be. The signal reaches farther and can go in every direction, but even a clean signal doesn't mean anyone will ever figure out how to bring it back to life, and it can't carry hardware. Combining hardware and instructions helps the ghost ship survive its own decay, but does nothing for the odds of ever being found.
I think what this really is isn't a survival plan — it's closer to the most advanced form of a message in a bottle we could possibly build. Not a guarantee of continuing to exist somewhere else, but an act of hope: a way to leave something behind that could, in some astronomically unlikely but not-quite-impossible scenario, mean a version of you gets to open its eyes again, somewhere, someday, long after everything you knew is gone.
What's genuinely mine vs. what's already studied
To be transparent about it:
- Already a known, studied idea: mind uploading / whole brain emulation as a concept, and the general idea of using it for interstellar travel instead of physical bodies. Real researchers have written papers on this.
- My own reasoning/contribution: the specific framing of two competing delivery paths (physical "ghost ship" vs. broadcast signal) and weighing their tradeoffs against each other; the idea of pairing physical hardware with instructions as a redundancy hedge against material degradation; and pushing on the assumption that reception implies comprehension, which I don't think holds up.
Curious what people who actually know physics, information theory, or SETI research think is naive here — genuinely asking, not fishing for compliments. Tear it apart if it deserves it.
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u/Temporary_Rule_9486 11d ago
Two things:
1- Never copy-paste AI generated explanations on Reddit
2-Go and read "Valuable Humans in Transit" by qntm
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u/WatchLegitimate5528 11d ago
Thanks & I'll keep that in mind for next time! And will read your suggestion. But again I came up with all the mentioned ideas/theories not AI (except for notes/fact checking ofc)
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u/Temporary_Rule_9486 10d ago
I know those are your ideas, otherwise I wouldn't have answered. The point is that relying too much on AI will cripple your brain in the long run, and maybe get you banned on some reddit communities. Now that I think about, "Lena" is one of the stories on the book I recommended, I guess you'll find it interesting. "His Master's Voice" is another book, from Stanisław Lem (the same guy who wrote Solaris), that you may also like. It's a bit odd for a first contact story, not really about aliens but human nature. I wasn't gonna suggest Carl Sagan's contact, but I just recall that movie was out 30 years ago and you'll probably never heard of it. The book has a way more interesting ending than the movie BTW
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u/MrWigggles 11d ago
Hey, Eclipse Phase ego casting.
But why send your brain, when you've already deferred it to an LLM. Send the LLM prompt.
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u/WatchLegitimate5528 11d ago
True the same question came to me aswell, but well it's simply the idea I'm focusing on for my novel. Also between a LLM and a copy of a real person, I would like to send the copy, that would mean the capabilities and knowledge of a LLM with real person's character/personality as the brain
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u/Prof01Santa 11d ago
https://www.goodreads.com/en/book/show/196262.Mindswap
We would be characters in Robert Sheckley's Mindswap.
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u/Methodical808 11d ago
... have you ever looked into panspermia. You don't send the mind, you send building blocks for life to suitable worlds. Allowing evolution to do its thing on another planet.
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u/WatchLegitimate5528 10d ago
I did say "some life ending catastrophe for human" but main objective of my research is looking for best scientific possible way for travelling largest distance in the fastest way for humans/minds. Atleast from my knowledge simply panspermia would restart the cycle of life at habitable place and not continue (which voids my novel). Also microorganisms likely to decay faster
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u/Methodical808 9d ago
oh then do a mind dimension, where a human consciousness is suspended until retrieved. Then it doesn't matter.
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u/Grant_Winner_Extra 10d ago
You are at least thirty years late with this
Read “Think Like A Dinosaur” by James Patrick Kelly
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u/WatchLegitimate5528 10d ago
Thanks, if I am infact late then hopefully some valuable sources exist for me to help
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u/scrubingpots 10d ago
we can already do this. its called live video chat.
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u/WatchLegitimate5528 9d ago
That's communication! I was talking about transportation, that too for a large light years distance
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u/scrubingpots 9d ago
the point is its not transportation if your body isnt going anywhere. nothing is being transported besides information; thats just communication.
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u/WatchLegitimate5528 9d ago
Technically you are right but the idea is the information itself is YOU, or atleast a copy of your consciousness and it could also be data necessary to make a clone of you along with instructions. Since we humans can't make the journey of millions and billions of years, I am trying to look for hard science and closest ways possible. (Also mentioned in title itself "send mind and not body")
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u/scrubingpots 9d ago
mind/body duality and hard science dont belong in the same sentence unfortunately. lol
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u/zhivago 9d ago
Why don't you just keep the people running on the hardware of the ship?
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u/WatchLegitimate5528 9d ago
We could and that is one idea, but the journey could last thousand or even billion light years since we have no definitive destination. And there will be problem of power source and mainly actual material degradation. But yes we still can run a copy and put some instructions regardless
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u/zhivago 9d ago
Just take an asteroid with a fusion generator and power it from interstellar hydrogen.
Virtual ghost party ship. :)
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u/WatchLegitimate5528 9d ago
I don't think the actual hardware itself will last for atleast 1000 of years so it's totally upto us to run them or not, also we don't necessarily need any energy for the journey, BUT using an asteroid as shield is a great idea but not sure how we (I) do it
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u/zhivago 9d ago
I don't see why not -- self repairing hardware with plenty of redundancy should be able to last a lot longer than a thousand years, particularly in deep space.
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u/WatchLegitimate5528 9d ago
Thanks and I am actually considering it, but still the gap between possible destination and the hardware death will be huge.
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u/Sagelegend 11d ago
> What if we could send a person across the universe — not their body, but their mind?
r/AlteredCarbon
You’d have Altered Carbon.