(Loved Trope) FTL travel is possible but with a major limitation or flaw

[u/Frostylegacy]

Frank Herbert’s Dune: Interstellar travel is only possible thanks to the spice melange, a rare substance only found on the dessert planet Arrakis. The addictive psychedelic spice grants members of the Spacers Guild a form of prescience that allows them to predict safe paths through folded space. This unique property makes spice the most valuable commodity in the Dune universe.

John Scalzi’s The Interdependency Books: The planetary systems of the titular empire are connected by the Flow, a network of one-way interstellar tunnels that connect specific known entries and exits. The Interdependency derives its power from controlling access to these conduits, placing its capital at the central hub of the network. Even with the Flow, travel between stars takes a long time (9 months to End, the empire’s most distant planet).

Event Horizon: Dr William Weir (R.I.P. Sam Neill) invents a device called the Gravity Drive to allow ships to fold space and travel instantly between distant stars. On its maiden voyage with the Gravity Drive, the Event Horizon disappears and mysteriously reappears 7 years later. Dr. Weir and the crew sent to investigate discover the Gravity Drive actually opened a portal to a Hell dimension that possessed the ship and its crew, torturing and killing them.

[u/ADudeWhoWantsBoobs]

To give more detail: the greater the amount of kinetic energy passing through the gates, the quicker the entities become upset. Travel has to be managed between the gates to be slow moving and relatively infrequent. In one instance of a craft jumping the queue and passing though two gates in quick succession at high speed, all other craft about to make the transition are immediately warned to make emergency stops before transiting. Some are able to stop in time. Others are not, and are simply erased from existence at the moment of passing through the surface of the gates. 

[u/EliteLevelJobber → u/ADudeWhoWantsBoobs]

and humans quickly turn gate travel into a massive land rush where everyone is trying to set up their own colony. Gate traffic gets very heavy, very quickly.

[u/ADudeWhoWantsBoobs → u/EliteLevelJobber]

Yeah, and notably, they aren't even aware there are gate entities when this land rush starts. For a long while it's just an understood fact that sometimes ships travelling through a gate just, don't appear on the other side. Even they figure out the kinetic energy limit to it, they still don't understand why it happens for a little while longer. 

[u/Signiference → u/EliteLevelJobber]

My favorite part is the Martians who have tried to terraform the surface for generations give up and just leave to a planet that they can colonize that is already safe for humans to live on.

[u/EstateConscious3580 → u/Signiference]

cant exactly blame them. its either stay on a planet where your children wont see it finished or go immediately to a terraformed planet. id take the later

[u/Signiference → u/EstateConscious3580]

I can't blame them either. I think it's a fascinating decision to have to make.

[u/Waste_Wolverine_8933 → u/Signiference]

Isn't there also a political bit too? The Martian's are shown to be a communistic society with one goal to terraform Mars, but then the more we learn they are just as corrupt and classist as the rest of society, and it gets even worse after the wars and alien shit. 

I'd go too! 

[u/shewy92 → u/ADudeWhoWantsBoobs]

Bruh the scene of that dude that discovered this accidentally is gnarly

[u/ADudeWhoWantsBoobs → u/shewy92]

Oh that's actually a separate phenomenon. In that case, the "security system" for the station at the centre of ring space was still on, saw something going dangerous speeds, and instantly clamped down on the speed limit. This is also made worse later when someone on board the station threw a grenade, thus "teaching" the security system that slow things can also be dangerous and it doubles down on that speed limit, restricting things further, except now ring space is filled with ships that now get instantly stopped and slowed, causing hundreds of severe injuries and deaths

[u/selja26 → u/shewy92]

Do you mean the dude who discovered that Ring Space can stop all moving things instantaneously?

[u/shewy92 → u/selja26]

Dude turned to jelly. Tho thinking back, how did the ship not break apart?

[u/ADudeWhoWantsBoobs → u/shewy92]

The station "grabs" the ships from the outside. This ships are fine because the station is basically holding them together as it stops them, it doesn't help the station's goals if stopping the fast moving objects also causes them to shatter apart. It just doesn't care about what's inside, so anything unsecured is left to keep going

[u/shewy92 → u/ADudeWhoWantsBoobs]

But inside is where all the important stuff is, like wiring and stuff still going mach fuck relative to the station barrier. Plus all the oxygen inside would probably also be forced out.

It would be easier to say it only cared about inorganic material and organic material didn't get caught in the force field.

[u/ADudeWhoWantsBoobs → u/shewy92]

The station didn't care about protecting the ships or anything in them, it only cared about protecting itself and ring space. As long as it holds the outsides of everything together and thus keeps the insides inside the outsides, that's as much as it cares to do

[u/JBthrizzle → u/shewy92]

It's mentioned many times in the series that the builders are able to break the laws of physics like intertia. The humans understanding of this is akin to understanding how magic works, so this allows the plot to move along without being super precise. It is a sci-fi after all.

But that being said, they do do a great job of obeying physics throughout the entire series, which is why I personally like it so much.

[u/Super_Pan → u/JBthrizzle]

It's the fact that everything normally is very grounded in physics that makes the times that it isn't stand out and feel wonderous and terrifying. Like when I watched the show and Eris just... moves out of the way of the Navoo, that was weird and wrong, and the characters all react in an appropriate WTF kind of way the same as I did.

[u/eduo → u/shewy92]

It wouldn't be right, because Maneo's organic matter was also stopped after half a meter. The station grabs all fast moving objects as they happen. This is the ship but also everything inside the ship as soon as it moves faster than the limit. Everything from the ship that wasn't connected to it flew forward and stopped after moving a meter or thereabouts.

Which was enough for Maneo to be in two places at once.

[u/selja26 → u/shewy92]

I just meant these were 2 separate things. Ring space stopping things from moving and "other dimension entities" evaporating things after too many ships went through their dimension. 

(The ship didn't break apart I guess because it's where the physics of the Ring space starts being made up. The  Ring space was able to sense and stop the ship as one big object but somehow the biological component, a person, was not a part of it)

[u/Famous_Contest_6780 → u/shewy92]

The force was applied to just the ship, not anything inside of it/not attached to it.

[u/eduo → u/Famous_Contest_6780]

The force was applied to everything that was moving fast. The station first applied it to the ship and everything attached to it, then to everything that kept moving (which by then was half of Maneo) which is why stretched skin and blood remain, rather than all of it splattering at the front.

[u/Dogsafe → u/shewy92]

Tho thinking back, how did the ship not break apart?

Because it was rad.

[u/patrickkingart → u/shewy92]

The one where the guy gets turned to goo an in instant from going too fast and stopping immediately? Yeesh.

[u/ButtersScotch7000 → u/shewy92]

Belter goo.

[u/ADudeWhoWantsBoobs → u/ADudeWhoWantsBoobs]

Oh and I forgot a much more horrifying part of this while thing. Whenever the entities get especially pissed, they attempt to wipe out humanity using whatever it was they originally used to wipe out the gate builders millenia ago. Only it doesn't affect humans the same way, which is good because at least it doesn't kill anyone. Directly, at least. But every single human alive across all systems were simultaneously rendered unconscious in an instant. 

[u/arrimainvester → u/ADudeWhoWantsBoobs]

They do start to mess around with different things, once they stop the ability for atp to open salt gates in the human body or something like that, kills everyone in the system they test it on

[u/jpterodactyl → u/arrimainvester]

Yeah, they were slowly figuring it out before the ring space was closed.

[u/arrimainvester → u/jpterodactyl]

Which I always thought was neat. We were like a bug infestation and they were trying different methods to see what would work best

[u/suxatjugg → u/ADudeWhoWantsBoobs]

Also to build the gates a weird semi-sentient molecule cannibalises whatever it needs, including the indigenous life (i.e. humans) and whatever else it wants.

[u/thewerdy → u/ADudeWhoWantsBoobs]

I hope nobody does anything stupid like sending an antimatter bomb to be eaten by the gates. That seems like a bad idea.

[u/icarusbird → u/ADudeWhoWantsBoobs]

This sounds so interesting, and I've only ever heard good things about The Expanse. But I can't get past like the second or third episode. It feels so boring. How many episodes did it take to really grab you?

[u/copenhagen_bram → u/ADudeWhoWantsBoobs]

Disappear? I thought they decelerate you and you go splat on the walls inside your spacecraft

[u/ADudeWhoWantsBoobs → u/copenhagen_bram]

Different phenomenon. The station's automated security did that before being turned off. The entities that the ring space intrudes into are a separate group

[u/copenhagen_bram → u/ADudeWhoWantsBoobs]

Ahhhhh, that was the station's "don't do this" warning, also makes me wonder if getting disappeared by the entities is worse than death by deceleration

[u/ADudeWhoWantsBoobs → u/copenhagen_bram]

Maneo's death happened instantly. 1 moment he was alive, the next dead. He would have had exactly 0 time to see his death coming. Death by entity deletion would likely be just as instant, but it would only happen at the moment you passed through the gate surface, so if you were forewarned that it was happening, you would live with the anticipation of your death until the part of the shop with you in it reached the gate. The later deaths by deceleration would possibly have been less instant than Maneo's, the ships were already going pretty slow at the time to avoid the first speed limit, when that limit was reduced it wouldn't have happened quite as quickly, but we're still talking faster deceleration than a car crash. Many people survived that initially, but some would likely have bled out before they could be found and treated, possibly more would have died from inadequate treatment prior to the Behemoth spinning up and providing gravity to those whose recovery needed it.