4

In my sci fi novel, a technologically advanced version of the human race is capable of harnessing and creating large amounts of antimatter for interstellar travel at 99% the speed of light , accelerating to those speeds in 10 hours before activating an alcuberre spacetime drive. However, with some rough math, I estimate that acceleration to that speed would put around 850g of force on the squishy humans inside the craft, causing them instant death. Unfortunately, due to the nature of the plot, the humans cannot undergo any genetic or cyborg upgrades allowing them to survive high speeds, in addition, in order to make sure the protagonist doesn't waste months just flying through space accelerating to the minimal speed required for the warp drive to activate. So here's the problem: How could a spaceship accelerate humans to 99% the speed of light in 10 hours without compromising the passengers on board (no physical modifications to the passenger allowed)

Zetrox
  • 438
  • 3
  • 7
  • 3
    If you're interested in hard science solutions, wouldn't it be just much simpler to avoid the need for a photon drive of unspeakable, planet-liquifying power fueled by planet-shattering amounts of antimatter (because that's what you need if you want to get to .99c promptly) and have a slightly longer speedup time and a slightly lower jump-starting speed for your warp drive? I mean, all these variables are within your control, so why not just tweak them to make stuff work? – Starfish Prime Feb 24 '22 at 14:54
  • 3
    Also worth noting that if you can get to .99c in 10 hours, then the business of making relativistic kill vehicles becomes straightforward, and that's not a good place to be. – Starfish Prime Feb 24 '22 at 14:55
  • Kzinti lesson. "Friends don't let friends write reactionless drives." "Torch ships are fantasy." – Zeiss Ikon Feb 24 '22 at 15:25
  • 4
    Zetrox, did you read the [tag:hard-science] tag wiki before using it? Every answer you've been given fails that tag and are quite literally under threat of deletion because of it. The [tag:hard-science] tag does not refer to a literary genre. What it does is force answers to prove themselves with mathematics and citations to accredited sources (like scientific papers). Did you actually need an answer that strict considering how fanciful the premise is to begin with? – JBH Feb 24 '22 at 17:24
  • 2
    I’m voting to close this question because hard-science answers to this are impractical. – John Dallman Feb 24 '22 at 17:40
  • 1
  • This question has been answered, as to effects of high-G acceleration through space on humans. – Vogon Poet Feb 24 '22 at 18:04
  • 1
    @VogonPoet not convinced; the question you've linked involves an order of magnitude less acceleration, and a positively sedate .1c target speed vs the fairly high relativistic speeds needed here – Starfish Prime Feb 24 '22 at 18:43
  • I don't see how hard-science can even apply where an Alcubierre drive is involved, but this question doesn't lend itself to hard-science answers anyway. VTC until it can be clarified whether hard science is wanted or the question edited to permit hard-science answers. – Zeiss Ikon Feb 24 '22 at 18:51
  • @ZeissIkon OP isn’t asking about the FTL portion at all, that’s just fluff. His question specifically calls for the 0.99c portion of the trip. VTSO – Vogon Poet Feb 24 '22 at 20:43
  • Sorry everyone, I'm new so I misunderstood the hard science tag as a genre, – Zetrox Feb 24 '22 at 23:59
  • @zetrox It's not problem, but if you [edit] your question to remove the hard-science tag, it can be reopened. Also, you shouldn't accept an answer at this time; you might get better answers after the question is reopened when answerers who avoided answering over the hard-science tag can chip in. – Zeiss Ikon Feb 25 '22 at 12:26
  • This problem seems entirely self-inflicted. As far as any real-life experiment devised has been able to tell, there is no such thing as absolute velocity: a spacecraft that has accelerated to 0.99c relative to Earth can consider itself to be at rest, and Earth to be moving at 0.99c. So, just don't require such a high speed. – Christopher James Huff Feb 25 '22 at 13:21
  • @ChristopherJamesHuff You know every FTL needs to “accelerate” if for no other reason than theatrical effect. Who would have watched Star Wars if tie fighters didn’t roar and flashlights didn’t sound like electric razors dropped in the clothes dryer? You won’t win this. Allow them to spend their wasted impulse fuel in peace. – Vogon Poet Feb 26 '22 at 02:20
  • Interesting comments to read here, lol.. has WB changed into a twitter site ? Why is this question not reopened.. the hard-science tag is gone and I don't read other objections.. (vtr) – Goodies Feb 28 '22 at 19:12

2 Answers2

2

Full Body Liquid Immersion

This doesn't actually work completely. I've been looking around online and estimates seem to suggest that this technique will, at best, work for around 200g of acceleration. But, hey, that's a pretty impressive 200g, and shouldn't push the acceleration window that much longer.

The theory behind full body immersion is kind of simple, it just comes down to shock absorption and support. If you submerge a human in a tank of shock-absorbent liquid (not water, it needs to be a little better than that), then the liquid will act to transfer the force equally as well as support the body under the intense strain.

The only problem is breathing, because the lungs will collapse at the point of 200g, so you need to fill it with liquid as well. Trouble is we haven't exactly cracked the liquid breathing yet, but if you assume that this society has, then you just need to dunk the subject in a specialized immersion pod, and there you have it! Admittedly, like I mentioned earlier, I'm not sure this method will stand up to the full 890g, so if anyone has a method that does, that's a better answer.

There's a useful question on our sister site that will give you more background: Space Stack Exchange, which is what I'm basing the majority of my answer on.

Halfthawed
  • 40,450
  • 5
  • 73
  • 156
0

Somewhat of a frame challenge: at this tech level, human bodies are fully expendable

At the beginning of the trip, passenger's consciousness gets transferred to a more sturdy storage (it could even be something like Amazon Web Services interstellar cloud). During acceleration/deceleration, everything is reliably secured. Once we are out of high g, new instances of human bodies are created and initialized with stored consciousness. Passengers wake up just like they do from a more traditional hypersleep.

Alexander
  • 42,224
  • 6
  • 59
  • 153