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How to Write About Long Distance Space Travel?

Extollager

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I want to use something that is feasible, and that could be potentially realistic, but that I don’t have to explain in depth so that it doesn’t make the novels “hard science” novels.
Bravo, bravo!
 

Al Jackson

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Actually neither do I really, but there is a something I would call 'plausibility' in fiction that is required. And that can be done deftly with little moments of show not tell. i.e. You should know that Federation spaceships run on dilithium crystals, 'cause there are episodes where the engine might blow up (cue eject the engine core, big explosion, enemy destroyed :)) etc... but I don't need to know at all how spaceships in that universe run on said macguffins!

Note, plausibility is not necessarily realism - although it can be. I also equally enjoy fairy tales, fantasy and weird fiction all having wide and varied 'plausibilities'
Robert Heinlein wrote most his science fiction , especially that before 1960,, with 'viability'. He used known physics to create a feeling of 'lived-in' advanced technology. He did this with a minimum of techno babble … in many cases he could have given a reasonable detailing of the engineering physics , since he knew it, but too much of that defeats the verisimilitude. The writers in the 1940s and 1950s worked hard at domesticated super science , it has changed, but movies and TV have ignored that artistic work until more recently.
 

Scookey

Author of the AD2045 sci-fi series
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If you are talking 70-100 years haven't you limited yourself to either stasis or generational travel anyway - regardless of propulsion type?
 

Daysman

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I may be edging off topic here, but a realistic solution depends on your reality - does your world have aliens?

If you have contact with aliens at a distance or through some inheritance of abandoned tech, you might make your spacedrive a genuine mystery, an official secret, give it historical context, etc. and just allow yourself to throw the switch.

If you have direct alien contact, there may be a business opportunity, a trading arrangement, maybe a co-op plan where your settlers build a habitat and for their part the aliens snap their fingers (or equivalent) and your community is moving at a small percentage of lightspeed... :)

But seriously, whatever 'real world' solution you choose, don't forget shielding... whether you're moving thru interstellar space at fractional c or dropping through a nondescript spacetime shortcut, there'll be accelerated particles of all kinds...

Have a good weekend!
 

Cathbad

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I may be edging off topic here, but a realistic solution depends on your reality - does your world have aliens?

If you have contact with aliens at a distance or through some inheritance of abandoned tech, you might make your spacedrive a genuine mystery, an official secret, give it historical context, etc. and just allow yourself to throw the switch.
Oh! Great idea!

Could have been reverse engineered too, I'd guess.
 

Cathbad

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Okay, I'm not a fan of "hard science", but I don't think a propulsion system to reach FTL speeds is feasible?
 

scarpelius

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Okay, I'm not a fan of "hard science", but I don't think a propulsion system to reach FTL speeds is feasible?
Short answer: No.

Long answer:
e=mc2 which means energy needed to even reach light speed will become prohibitive.
So, to accelerate 1000 tones of people and equipment (we can assume a spaceship will weight in that neighborhood) to the speed of light, you will need 90,000,000,000,000,000,000,000 Joule of energy. That is about 21,510,516,252,390 megatons.
Castle/Bravo the biggest US atomic detonation was 15 megatons (63,000,000,000,000,000 J) and the Tsar Bomb tested by Russia was 50 megatons (210,000,000,000,000,000 J).
By comparison:

90,000,000 PJ needed to travel by light speed
210 PJ Tsar Bomb = 428,571 bombs
63 PJ Castle/Bravo bomb = 1,428,571 bombs

Tsar bomb weight 27 tons which means you need a total of 11,571,417 tons of fuel to accelerate a spaceship of 1000 tons to the speed of light and that is ideal case where the energy is 100% converted in velocity.

P.S. I hope my calculation are correct, just picked numbers from internet.
P.P.S. Relativity theory is our best work case. When a new theory is going to be developed and proven viable, those numbers might become obsolete and maybe made FTL possible.
 
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Al Jackson

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Slightly off-topic, but there are a couple of TVTropes that are kind of relevant
No Sense of Distance / Sci Fi Writers Have - TV Tropes
Sci-Fi Writers Have No Sense of Scale - TV Tropes
This kind of article pisses me off. Who ever wrote these has no knowledge of the history of science fiction!
Maybe it is true of 'Sci Fi' writers.... meaning TV and movie science fiction, but it is false to say this about writers of prose science fiction!
Starting the late 30s, when John Campbell took over Astounding , he had a degree in physics, this editor started laying down the law …. get your facts about the universe straight! or I am not publishing your story.
In the 1940s we have the appearance of Heinlein, Asimov and Clarke (and about 100 other SF authors) who got things like the distances and scales right!
SF writers knew , early on, that solar system distances and interstellar distances were Godzilla miles different from one another, that is why Faster Than Light travel was invented.
I have to admit that TV and Film has been slow to come around , Star Trek , back in 1966, started getting it right (mainly due to Roddenberry's familiarity with the prose form) but it still goofed now and then.
I really don't know of any good prose SF since about 1950 that gets distances in the universe wrong so the gest of those articles does not apply to the written form.
 

Daysman

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SF writers knew , early on, that solar system distances and interstellar distances were Godzilla miles different from one another, that is why Faster Than Light travel was invented.
I always liked the classic hyperspace jump...

Old Man's War (author John Scalzi) updates it nicely by jumping between essentially identical universes.

Also, shielding, people! You're gonna need shielding!
 

J Riff

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just fold up some space yknow... like paper, used to write all kinds nonsensical rubbish on, SF included. )
 

Venusian Broon

Defending the SF genre with terminal intensity
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This kind of article pisses me off. Who ever wrote these has no knowledge of the history of science fiction!
Maybe it is true of 'Sci Fi' writers.... meaning TV and movie science fiction, but it is false to say this about writers of prose science fiction!
Starting the late 30s, when John Campbell took over Astounding , he had a degree in physics, this editor started laying down the law …. get your facts about the universe straight! or I am not publishing your story.
In the 1940s we have the appearance of Heinlein, Asimov and Clarke (and about 100 other SF authors) who got things like the distances and scales right!
SF writers knew , early on, that solar system distances and interstellar distances were Godzilla miles different from one another, that is why Faster Than Light travel was invented.
I have to admit that TV and Film has been slow to come around , Star Trek , back in 1966, started getting it right (mainly due to Roddenberry's familiarity with the prose form) but it still goofed now and then.
I really don't know of any good prose SF since about 1950 that gets distances in the universe wrong so the gest of those articles does not apply to the written form.


Erm... in the main article that the trope is connected to and the second one that M Robert Gibson linked to the writer actually states: "This is chiefly true of creators of TV, film, and video game SF. Creators of written science fiction can be positively obsessive about accuracy. (Although sometimes there not - See Sturgeons law!) If your qualitative yardstick is based around an author's ability to describe distances, this may be a useful way to distinguish good print science fiction from bad print science fiction. And it's why a lot of science fiction fans don't like the movie and TV adaptations of their favourite books and stories"
 

Daysman

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Coughs... anyway, back on topic...

Background to scatter sparingly through the tale...
  • an unspecified nuclear fusion drive
  • a fusion fuel (mixture) gathered by interplanetary mining operations over decades
  • a mountain of inert propellent to be exhausted as plasma (guessing frozen ammonia or maybe some low density / low nuclear mass / high cross section smart material that's easy to handle) that also serves as shielding against on coming interstellar debris and the output from the drive...
  • years of low acceleration to a small fraction of lightspeed
  • years of deceleration, so more fuel and propellent
  • you could also deploy an electromagnetic breaking system (interacts with the galactic magnetic field) but this largely depends on if this is a moonshot or a reusable transport system, and on the scale of the vehicle. You may need it for course adjustments anyway...
  • If you're transporting biological humans, they might need to be radiation hardened (no idea) or have medical tech that monitors for and repairs radiation damage
  • To avoid hypersleep (other fictional biological suspension systems are available) why try induced torpor?
    • Not sure it would extend life without other medical tech, but it reduces resource demands and also bodily wear and tear...
    • Could be applied each night cycle instead of sleep or as part of a monthly duty cycle? Aren't NASA looking at this???
    • It might be enough to get your crew there...
    • Not real yet, AFAIK ;) but may be plausible
Edit: my mistake, ammonia may actually be a candidate fusion fuel... anyway, must get on...
 
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J Riff

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Obviously no signigant interstellar travel can happen at sub-light speed... and you can't pass light speed... so back to 'termite holes' (I'm tired of 'wormholes') you go...
 

Serendipity

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A lot of people are hung up about interstellar travel meaning covering an inconveniently large distance between stars. But 70,000 years ago, Scholz's star passed through our Solar System, albeit it only got as close as the Oort Cloud. But the point remains, we as a human race can star-hop if a star comes close enough to our Solar System! It's a case of sitting and waiting...
 

Al Jackson

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Obviously no signigant interstellar travel can happen at sub-light speed... and you can't pass light speed... so back to 'termite holes' (I'm tired of 'wormholes') you go...
Hyper Drives and Jump Drives and other SF FTL had no physics behind them other than a 'unknown' physics as method of telling stories with interstellar settings, man all that goes back to the 1930's , John Campbell invented the term 'Warp' drive back then. When black holes came along SF writers thought of using these as jumps but the real physics showed this was impossible. However Kip Thorne and his grad student did find a way in 1988 with the 'traversable wormhole' , oddly, all the physics works out. However the engineering physics is probably more than 10,000 years in the future. The instrumentality to do traversable is probably Kardashev type III !!!!
 

Al Jackson

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Erm... in the main article that the trope is connected to and the second one that M Robert Gibson linked to the writer actually states: "This is chiefly true of creators of TV, film, and video game SF. Creators of written science fiction can be positively obsessive about accuracy. (Although sometimes there not - See Sturgeons law!) If your qualitative yardstick is based around an author's ability to describe distances, this may be a useful way to distinguish good print science fiction from bad print science fiction. And it's why a lot of science fiction fans don't like the movie and TV adaptations of their favourite books and stories"
The author of the 2nd piece does mention written SF , missed that, I would not say prose authors are 'obsessive' , they just are attentative for the sake of enhancing the drama with realism.
 
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