How do you imagine the large picture of space warfare would shape into in a universe with the following characteristics:

  • There is FTL, but it's just available in very large and expensive platforms, in two forms: either artificial wormholes or really expensive specialized spaceships.
  • Weapons are, basically, rail cannons or multi-cannons and missiles with varied warheads, including nuclear or nuclear-like warheads.
  • There are no soft-scifi shields nor exotic metals (at least not enough to shield entire spaceships).
  • This weapons/defense make spaceships and actually most assets quite frail and easy to damage. The best defense against missiles are active defense (point-defense guns?) and ship designs that can keep somewhat operational even after multiple bullets have ripped fully across the ship.
  • Vastness of space around points of interest (cities, bases, asteroids, etc) make them hard to defend even against small forces.
  • Accelerating and moving around in speeds up to relativistic is rather cheap. Possibly through an hydrogen or easily obtainable refined source.
  • Energy is cheap, either from stellar sources or reactors.
  • Building quite large structures, including large solar panels, ain't exactly cheap, but ain't unfeasible and are rather common-place, as long as they keep light in terms of density, quite like the ships previously mentioned. Advances in material engineering (no exotic stuff, though) and methods like printing and ai designed structures make it feasible.
  • There are beam weapons, but it's rather easier to aim from distance with a magnetic machine-gun using cheap mass ammo that'll rip a ship to shreds. Missiles are rather hard to land, because aiming computers can track them easily.

How would the large picture of a conflict evolve in such setting?

How would spaceship crew behave during a battle?

What kind of warfare or tactics would emerge?

What kind of weapons and platforms (ships and else) would be built and eventually succeed (or not)?

I imagine stealth would play a large part on this, but I wonder about how the vastness of space helps this and how well detection tech can actually be nowadays or in not-so-far future (links would help).

I imagine ai will play major role in controlling weaponry and even ships themselves. I even feel that, if not fully ai-operated vessels, at least telepresence will play a major role.

I also imagine that, due to the previous stated, spaceships would have to be build in orbit or open space, and only shuttle like ships would actually be viable to get into and out of planetary bodies, right?

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    $\begingroup$ Welcome to the site Fernando. Please take our tour and refer to the help center for guidance from time to time. You'll find that we like single focussed questions, it seems that you have several here. You can edit this down to just the one, then post any further questions in their own threads, linking them if you wish. For now, 'till you can edit this down, I'm voting to put on hold to prevent unhelpful answers from being posted. $\endgroup$ Commented Dec 7, 2021 at 23:42
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    $\begingroup$ @FernandoDAndrea welcome ! Nice questions, but try to focus on one (see remarks above) and I have changed the hard-science tag into "science fiction". There is no hard science answer for any of your questions. Especially FTL would inhibit any truely scientific answer. If you don't agree with my edit, please undo it.. $\endgroup$
    – Goodies
    Commented Dec 8, 2021 at 0:26
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    $\begingroup$ Similar in premise to Kate Elliott, Unconquerable Sun (2020). $\endgroup$
    – ohwilleke
    Commented Dec 8, 2021 at 1:08
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    $\begingroup$ For the very expensive ships approach to FTL, some of the answers to this related question might be of help. $\endgroup$ Commented Dec 8, 2021 at 3:39
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    $\begingroup$ i recommend watching/reading The Expanse for inspiration. it's pretty close to your requirements (FTL only via "The Ring", no beam weapons except a communication laser turned up to 11) $\endgroup$ Commented Dec 8, 2021 at 6:59

12 Answers 12


Guerrilla Warfare

Space is big, like really really really big. What this means is that unless you are at a "point of interest", you can't be found.

You build your bases and forces nowhere near anything which means you can't be found.

You jump in and hit whatever you want to and jump back out to safety.

Eventually everything of significant value will be hidden.

  • $\begingroup$ So that might push towards the creation of new detection tech for long ranges or that'd be physically ruled out or "magic"? $\endgroup$ Commented Dec 11, 2021 at 0:03
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    $\begingroup$ There is approximately 400 billion stars in this galaxy alone. The closest star to us is 8 light years away. The milky way is 200,000 light years across. Detection across those distances would have to be magic. $\endgroup$
    – Thorne
    Commented Dec 11, 2021 at 8:27
  • $\begingroup$ Oh, I didn't mean that long range. Just within a star-system, maybe even quite less than a light-hour radius. This way one could search a suspected star-system going from body to body searching for POIs. Doable or magic? $\endgroup$ Commented Dec 12, 2021 at 21:59
  • $\begingroup$ There is 400 billion stars in this galaxy. Even searching one system at a time will take forever. Plus why do they need to be near a star? They could hide in a nebula or a rogue planet without a sun. $\endgroup$
    – Thorne
    Commented Dec 12, 2021 at 23:22

FTL changes everything.

Of all of the features of your question, the FTL one has the most implications (not the wormhole bit, the FTL ship bit).

When dealing with velocities and objects in space, all objects are 'frail', as the energies of any collision from extreme speeds overwhelms any material, or defence. This not just includes spaceships, but stations and even planets.

With FTL, the game completely changes. In fact, the ability to travel faster than the speed of light is quite 'magical' and requires complete overhaul of modern physics. By doing so, you are able to overcome causality, as the speed of light is not actually about light, it's how fast a 'cause and effect' can occur. It is actually the Speed of Causality.

So your universe would be quite bizarre. By travelling 'faster than causality', you could:

  • receive a message before you sent it.
  • destroy something before it is made.
  • witness something before it happens.

All sounds a bit ludicrous - hence why many physicists consider FTL impossible and the speed is actually a fundamental property of the universe needed for it to exist. I would recommend reading the principles of Special Relativity and General Relativity to get the basics - it may be in fact more interesting to consider the implications without FTL, as it is quite fascinating. So to your questions:

  • How would the large picture of a conflict evolve in such setting? Anyone with FTL capability has command over time. They would be able to manipulate both large and small to achieve dominance before you even become aware.

  • How would spaceship crew behave during a battle? I challenge the concept that there would be any battles at all, as there would be no need for battles. An FTL civilisation could easily know about you before you yourself knows, so would be able to prevent battles.

  • What kind of warfare or tactics would emerge? By having such power, the main question would be how would you prevent the destruction of all, including that of yourself? I would imagine a strict policy of non-violence (perhaps even non-violation of time) would be in place.

  • What kind of weapons and platforms (ships and else) would be built and eventually succeed (or not)? The only weapon you require is your FTL ship.

  • Spaceships would have to be build in orbit or open space, and only shuttle like ships would actually be viable to get into and out of planetary bodies, right? One would imagine if you have the ability to overcome the limits of spacetime, that you would be able to overcome simple limits of gravity. You could build your ship anywhere you wish with such knowledge.

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    $\begingroup$ You are doing the common mistake of equating seeing a cause with having a cause. Speed of light is limit on seeing the cause. I will give an example. The nearest star from earth is 4 light years away. It means anything that happen there is not known to earth till 4 years. Suppose something happen to it now, this minute. I will not know about it till 4 years because thats how long it will take its light to reach me. Now suppose somehow in 5 minutes from now I reach the star. What will I see? Obviously I will see the event already happened. $\endgroup$
    – Atif
    Commented Dec 9, 2021 at 4:22
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    $\begingroup$ @Atif I'm not commenting on just the speed of light, but the speed of causality. The problem is that in Special Relativity, the speed of causality is the only way an order of events is possible for which all observers agree on. If it is exceeded, then all observers do not agree on a sequence of events. This does not make sense, because if true the fundamental tenant of 'cause' before 'effect' is broken. The tenant is necessary for agreed events and FTL is thus meaningless. It is like saying something is 'blacker than black', or 'north of the North Pole'. It is not possible with good reason. $\endgroup$
    – flox
    Commented Dec 9, 2021 at 4:28
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    $\begingroup$ Observers may disagree as much as they like. That has nothing to do with cause always happening before effect. If your only sense is hearing and a bullet from a G-3 rifle hit you before you hear its sound coming then you cannot conclude that the bullet has broken casualty. Shortcoming of an observer is entirely different thing than cause always preceeding effect. If in doubt go to source. Whatever happen at source tell what preceeds what. Observers are limited by their senses that rely on photons that have speed limit. Cause itself dont rely on senses. $\endgroup$
    – Atif
    Commented Dec 9, 2021 at 4:34
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    $\begingroup$ @Atif You need to understand Special Relativity - and all it's implications. There are two fundamental truths in it: 1. Laws of physics are the same in all reference frames. 2. The measured speed of light is the same in any reference frame. Thus, your speed towards or away from objects has rate of time dilated in order to meet truth 2. If something is moving away close to C (speed of light) its rate of time relative to you slows close to 0. If it travels at C, it is 0. If it travels faster than C, it is under zero - and no longer makes sense. Its order of events now breaks truth 1 (causality). $\endgroup$
    – flox
    Commented Dec 9, 2021 at 4:39
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    $\begingroup$ @Atif There is not enough space here in comments to go into detail - but absolutely "Observers don't have to agree on sequence of events" is not true. You are thinking practically as if light was sound. I'm thinking physically using principles of a well established theory. There are too many points in your comments though to go through each one, suffice to say I would recommend going through some literature and papers on the subject. $\endgroup$
    – flox
    Commented Dec 9, 2021 at 9:26

Frame Challenge: they can’t be frail

You say that acceleration to and travel at relativistic speeds is cheap.

If that’s the case, then railguns, missiles, and explosives are laughably ineffective against your ships, because mass shielding is table stakes for travel at any meaningful fraction of C. A single fleck of paint, thousandths of a mm in diameter, traveling at 17,500 mph, can dig a crater into a 1-inch-thick reinforced glass window on the ISS. 1% of C Is more than 6,000,000 mph, four orders of magnitude faster. In order for traveling at that speed to be possible, much less cheap, you have to have immunity to debris.

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    $\begingroup$ Not necessarily. You can also make the ship as flimsy as possible so debris just punches straight through without causing major damage and operate under extreme redundancy conditions (ie expect a certain amount of the ship to be destroyed in every crossing) for major components that would object to having holes punched in them. Do it right and all you have to do is keep patching holes in the hull and occasionally replacing key components. The ship following behind you is screwed though. $\endgroup$
    – Joe Bloggs
    Commented Dec 8, 2021 at 12:23
  • $\begingroup$ If the fast part is in a wormhole or another dimension, it doesn't matter and can be frail. $\endgroup$
    – ohwilleke
    Commented Dec 8, 2021 at 19:17
  • $\begingroup$ whipple shields can disintegrate a very fast moving small particle, but a slower heavier cannon goes right through. Also, if ships can move relativistic speeds, so can cannons and missiles; so, "frail" may just be a relative term here. $\endgroup$
    – Nosajimiki
    Commented Dec 8, 2021 at 21:19
  • $\begingroup$ Maybe having an ablative shield facing forward could give fast ships a chance? $\endgroup$ Commented Dec 11, 2021 at 0:06
  • $\begingroup$ @JoeBloggs that's interesting. But travelling within one of these would be something quite dangerous, right? $\endgroup$ Commented Dec 11, 2021 at 0:07


Flox has a good answer about FTL and time. I'll focus a bit more on the raw physical side.

Nuclear weapons would lose most forms of their use. That is, their raw destructive power is over shadowed by simple forces. A proposed highly destructive idea is simply dropping a big rod of heavy material from orbit. Depending on weight and shape it can be as destructive as a nuke. A nuke would still have uses if it can interact with electromagnetic forces for EMP effects, which are better higher up in the atmosphere. So nukes can still have a purpose. Destroying all (most?) electronics and leaving much other infrastructure standing.

You however have easy relativistic speeds and rail cannons that probably can easily get things up to these speeds. Repeat the same exercise with dropping something on a planet, only you fire it or use a simple spaceship that accelerates to relativistic speeds and crashes into a planet. The planet is wiped clean of all life and any show of civilization. That means literally anything can be a weapon, as long as it can be fired from a railgun or allows relativistic propulsion to propell it. Just for fun you can grab a cloud of hydrogen, the lightest element, and put it in a container. Accelerate it to C, release a cloud of gas and watch utter destruction by something normally so harmless.

Of course you mention that 'up to' relativistic speeds is easy. That still means you can wreak utter devestation with a ton of perspectives on what the relativistic speed is. Just shy of that speed still represents devestation.

The smart thing to do would be to have your main civilization hidden, most rather not on planets. Any trading is done at remote outposts with a lot of secrecy where the materials for a colony go to. Same for all mining and such. Stealth is first and foremost to hide your own assets and not the space ships. The moment they are discovered, you need to be able to detect and avoid a relativistic or possibly FTL speed projectile that can come from anywhere. It can be fired from lightyears away and be auto correcting with tiny rockets or the like. At close to C the time if detection, which at best is at C speed, is too small to react even if you detect it. At FTL or simply C there is no way to detect it (with 'normal' physics. FTL doesn't really go together with our current understanding).

So either be unpredictable and always travelling, or be discovered and utterly destroyed.

Then again FTL should solve a lot of issues. Warfare might be a thing of the past. With lots if not all work automated and resources likely to be in abundance you can only really fight over ideas and stand points. Although this has happened plenty in the past, our society has become relatively less violent over time. Transgressions that warrant death now have a higher threshold for most societies. This trend can continue, allowing abundant societies to live and thrive together.

The bigger challenge in such societies is battling depression.

  • $\begingroup$ A heavy rod fired from space is affectionately known as "A Rod from God"....... $\endgroup$
    – Thorne
    Commented Dec 8, 2021 at 23:22

"Accelerating and moving around in speeds up to relativistic is rather cheap" -- that, right there, changes everything.

To defend, you can have a floating wall of self-aiming missiles. It will be next to impossible to avoid them all, so an incoming ship or flotilla would have no chances.

This means that planets, and everything else that is predictable in spacetime, is a big no-no -- because you can aim a cloud of relativistic shrapnel against it, and it will be like trying to stop a nuclear explosion with your hands. Unless you can withstand terrifying heat and pressure and build your base in the weightless center of a sizeable planet, and keep access shafts open somehow, other installations will be sitting ducks. Even having enormous "Whipple shields" orbiting around them is not going to be enough: you can defeat a few tungsten rod penetrators, but a stream of them will be the end of you.

Space stations would then travel at high speed in unpredictable directions, under emission control and being as stealthy as they can, and might try to maintain a hyperlight warning system - just a cloud of the appropriate gas, even extremely rarefied, would give a distinctive ionization signal when pierced by a c-fractional impactor. Satellites analyzing the trail using telescopes could get the news within a few seconds of the impactor's transit, and relay it at low cost and light speed to a wormhole relay one light-hour distant.

The Solar System has a radius of about six light-hours, so you can cover it with approximately 34 relay stations (the formula should be N = 5.4 Radius/Range; here radius is 6, range is 1). This gives the centralmost volume about five hours' warning.

At the same time, you will probably want to have at least a couple of unmanned fake and not so stealthy space stations whizzing by at random to further increase your chances.


How would the large picture of a conflict evolve in such setting?

How would spaceship crew behave during a battle?

What kind of warfare or tactics would emerge?

What kind of weapons and platforms (ships and else) would be built and eventually succeed (or not)?

I would imagine something like freighters in high piracy/caravans in high banditry risk areas on Earth. Once in system, the main caravan and some of the escort might coast with lights off and engines still to avoid notice while some of the armed escort would be offset looking for any trouble while distracting attention from the main silent and dark caravan coasting to a regrouping point slightly offset from the actual destination when local escorts could join their own escorts to help secure them on the way in with a final approach that couldn't be hidden.

Some combination of a lightly armed crew (with small arms sensitive to not breaching the hulls or structural parts of the ships) mobilized to deter the very lowest level and least serious boarding parties, with a shift to a hide or submit tactical approach when any other hostiles more threatening to them appear, combined with armed escorts designed to keep moderate threats at bay.

The commercial ships would have a way to jettison cargo (except for a few high value low mass items like information and jewels and nuclear or exotic fuel) which woulds usually be what attackers would want to preserve the lives of the crew in a rapid escape maneuver - perhaps in as many directions as possible like fleeing herd animals with the hope that at least some get away from the wolves or the lions, and the armed escort ships serving as rear guards.

The armed escorts would not have their own independent FTL and instead carried by commercial ships, in part, to increase their claw to size ratio and make them smaller targets, and in part, to discourage them from abandoning the folks they are escorting.

In the face of major threats caravans pooling the costs of armed escorts would simply dump and run without even trying to have the armed escorts resist. Boarding parties would be brutal but leave witnesses or gory evidence in cases where their victims didn't.

Hostiles might be "barbarians" on the model of the Vikings or "Migration Era" Europe that have a society built mostly on raiding income working out of a major black market network. All out international wars or wars of conquest would make less sense and disrupt the society necessary to keep FTL technology running too much to be sustainable for very long at all.

Something like a protection racket would arise around small settlements that don't have the resources for effective patrolling.

All of the baddies would be predators managing the herd, but not squeezing so tight as to cause FTL ships or marginal settlements to collapse entirely leaving them with no one to raid.

Well patrolled major routes and major settlements that could afford large fleets of patrol craft would be heavily favored over much more risky trips to the hinterlands on ill patrolled routes to ill guarded places, making those places more marginal economically while central route places would thrive.

I would imagine something like small, fast, not FTL ships with lots of ordinance that are individually disposable but would greatly outnumber of bandits/pirates and would be focused more on attrition than on capture, again, more focused on making examples of the baddies than anything else. They "good guys" wouldn't need to board to get cargo or hostages, they'd just blow pirates into the void and kill them on sight.

The goal for the armed escorts would be to present as small and shifty a target as possible and to strike as soon as possible after a threat is confirmed.

Privateers converted from pirates to mercenaries might also be a thing, as both escorts and as settlement patrol forces, blurring the line between protection rackets and outsourcing of a government function.

The exact weapons wouldn't matter much since everyone is fragile. Like modern fighter dogfights, it would probably be first to see, first kill once hot firing begins. Commercial ships would be unarmed to reduce their attractiveness as priority targets, but with as much speed when freed of cargo as they could muster to enhance their capacity to flee.

The divide between manned and drones would be tricky. Something like the loyal wingman concept with each manned armed escort having one or more armed drones supporting it, might make sense. Too much socially complex decision making for pure AI, but a world without drones wouldn't seem very realistic. Settlements might have drone warning stations that pirates would try to circumvent.

Pirates might have a two wave strategy with an first wave of armed craft some converted from commercial or out of date, or repaired and captured or otherwise makeshift without access to core civilization in the fore and with large boarding parties, and a second collect the loot wave in the far rear with marginal commercial and industrial craft that weren't combat worthy. They would be scattered all over the area before an attack to be less visible and less vulnerable to a concentrated attack from good guy forces, and with a better chance at plausible deniability to pass as legitimate commercial ships.



The key in your scenario is that even a weak ship can destroy a much more powerful one, because no one has any "armor". So the only way to destroy an enemy is to make sure they don't notice you until you attack. This makes me think of a few tactics.

Hit n' Run

Now, you said that ships can "[accelerate and move] in [relativistic] speeds". One option here is a hit and run tactic, where a ship comes in at insane speeds, blows up a station, defence platform, or other ship.

So, therefore, here's my view of a typical fight. Some space station orbits a planet; it has a massive point defence grid and lies in a asteroid belt, to which the only easy entry point is a heavily guarded dwarf planet ring clear.

A ship comes in at 2% of c, an insane speed. It rips through the PDC grid, and hits the station with ~100 railgun shells. Maybe a nuke or two. You no longer have a station.

Fire and Forget

In space, there's not much that will influence your shots. Rather than ships, this tactic uses massive space platforms, with minimal thrusters. A station will slowly move to a jumpgate, get close (like 1 or 2 AU, so not THAT close.) to another ship, then fire a series of railgun shells or missiles at another station, across the vast black of space. Do something to the shells/missiles so they can't be detected (turn off their engines, make them non-reflective, etc.)

A few hours later, express a feeling of glee as the enemy platform goes up in flames — or one of dread as your own does.

Wall of Bullets

Instead of a ship, imagine a station. The station has been built up over the years, and it is a massive thing. It is bristling with auto-tracking PDCs, which have a simple setting. Any object that does not emit a near-unbreakable hash is destroyed. Nothing gets past it — that is, until another station fires exactly the same armament at it. Awesome fight scene!

Ship Design

Even with all of these limitations, ship design is wide and varied. I see a few ways.

That's No Moon!

Utterly massive stations allow for gargantuan power generators and defences. Also, more self-sufficiency allows for longer trips. See tactic "Wall of Bullets"

Fast And Nimble

A fast ship is a dangerous ship. And the smaller it is, the harder it is to hit. Using this, you can imagine a small ship that runs through defence grids to destroy enemies. See tactic "Hit n' Run"

One Big Gun

A station could be used to hold a lot of people, but it could also be used to hold a GIANT gun. See tactic "Fire and Forget"

More may be added

  • $\begingroup$ Actually, I've said accelerating is cheap, but not instant. And it will take time to reach relativistic speeds, yes, but it'll also take time to decelerate into orbital speeds. $\endgroup$ Commented Dec 12, 2021 at 22:24
  • $\begingroup$ That's not quite what I'm suggesting. Basically, accelerate from far, far, away, then fire your shells when pointed at them. So you're not slowing down; you're just continuing at the same speed. $\endgroup$ Commented Dec 13, 2021 at 15:44

Very similar to modern navel warfare, but with a few twists

Ever wonder why a Nimitz or Gerald Ford Class carrier has never been sunk despite thier involvement in several wars to date? Sinking them is easy, it would only take a single missile... the very very very hard part is actually getting a missile to them. They are protected by powerful electronic and counter electronic warfare systems that are so massive that no missile or aircraft can begin to compete. They also have a plethora of support ships and aircraft ensuring that nothing ever gets even remotely close to it.

Your FTL ships will likely operate in similar carrier battle groups. You warp in very far away from the enemy. Far enough away they can not target you with cannons or slip a missile past your point defenses. Then you launch smaller support ships to extend your field of awareness, deploy advance defensive systems, etc. all to increase your elbow room and make it harder for the enemy to get close enough to hit you.

Then you launch your swarm of expendable drones to actually try to close range with the enemy. It only takes one getting close enough to deliver a fatal hit, but you have to get past the enemy's own advance defenses and drone swarm first; so, you will have a lot of drones sniping each other until one side runs out of drones leaving their FTL carrier vulnerable for someone to get in close enough to land a hit. In most cases, a carrier will warp away before you get close enough for a kill, but this also means leaving behind all of thier deployed drones. Without the powerful EM systems and command and control capabilities of the carrier, the drones left behind become easy to mop up; so, even if the crew and carrier lives, being forced to retreat effectively removes the carrier from the war... unless you have a large reserve of drones and support ships on standby to replace them.

As for crew: the carrier will probably be the only ship with actual living people on board. Your combat ships will need to pull non-survivable G-forces as they move and evade; so, best to keep them purely AI. Your actual humans on the carrier will have two main objectives. Your command crew will be responsible for top level decision making: declaring objectives, prioritizing targets, changing formations, etc. You will also want many junior crewmen responsible for and analyzing data looking to tag and classify any anomalies that the AI can not figure out. Is that grey blip in grid {124, -27, 89} piece of errant debris or a stealth bomber trying to flank your carrier?


To me what you are describing sounds a lot like a MAD* scenario, with similarities to nuclear weapons and intercontinental ballistic missiles.

*Mutually Assured Destruction

Given the technology to warp space time and accelerate items to decent fractions of the speed of light, it would be possible to destroy not just ships and opposing forces, you could destroy entire planets and multiplanetary civilizations with very little means of defense available. Given these destructive abilities, groups with the power to do so are deterred from violence due to the very real possibility that any aggression would be returned ensuring the destruction of all groups involved.

On the upside, the high expenses required to construct these FTL technologies would make them limitable and controllable. Expect groups with this technology to be very concerned about controlling the spread of this technology and preventing untrusted factions or groups/civilization from acquiring it. Some obvious parallels would be the controls on nuclear proliferation and military and diplomatic actions taken to prevent others from gaining these weapons. This could involve controlling information tracking any specialized materials required, tracking your enemies large scale construction projects, or other means of prevention.

If there are multiple militaristic factions in place expect a cold war situation to be in place. There will likely be proxy wars, espionage, attempts to develop technology to defend against first strikes, and great effort spent to detect and circumvent any second strike capabilities. Overall a fertile world for lots of interesting stories.


Folding Spacetime

Q: "Artificial worm holes" "What kind of warfare or tactics would emerge? "What kind of weapons (..) "Stealth would play a large part on this (..)"

Artificial wormholes (or jumpholes) are stealth !

Suppose you'd find a way to fold and punch spacetime, then travel through it, like going through a natural worm hole, but much quicker. Your target will be right "below" you.. you drop your ship into it.. and then fold back space time. For the military, it would make instant attack possible. The best stealth there is: Your battle cruiser simply appears, there is no approach.

About safety, don't worry: the move is a matter of seconds. For the outside observer, on either side, your vessel would look stationary. You won't collide into anything, there is no matter outside space time. There is a chance you'll end up inside a star on the other end.. but suppose the chance of that happening is within safety limits, or there exists a sensor to prevent it..

Artificial worm hole as a long range weapon

Folding space time will introduce high curvature (=gravity) where the fold is. This fold will exist very temporary, causing a artificial gravitational field along the fold. This will invoke a gravitational pulse. In regular space traffic, a ship using this technology must carefully plan the point of departure, use multiple jumps to reduce fold range, and avoid making the fold too sharp. Your FTL travel could take days instead of seconds, the artificial wormhole gets longer. In SF like Startrek the method using short range folds as propulsion is called "warp drive".

In military application, a much sharper folding may be thinkable, involving a relevant temporary mass to appear near the enemy planet, appearance and disappearance causing a gravitational wave. These waves don't hurt much, except very near the source location ! When the fold is placed accurately over a planet surface, your ship may cause havoc from light years away, by just activating the artificial wormhole.


The main defense ships would have are probably flak cannons. Flak cannons launch shrapnel and are primarily used for offense in media. If you have high-speed flak cannons you can launch debris into the path of railgun shots and missiles, slowing them down and potentially getting rid of them entirely.


You raise a lot of points but to answer them a certain number of assumptions have to be made about the ‘universe’ your operating in. Firstly, you haven’t really defined the parameters of your FTL drive rather than simply saying it exists. Most SF story & film settings tend to put some kind of limitations on FTL drives for the purpose of generating narrative and plot. Popping into space anywhere you want, at any time, at no cost and being able to instantly disappear again (also at no cost) makes for a rather confusing/disappointing story line.

So, if I may I’ll make the following assumptions;

  1. The FTL drives have limitations, i.e. they are reasonably large, reasonably expensive and have limitations on range & accuracy i.e. when using the drive there’s some kind of inverse relationship between distance traveled and the ability to arrive at your chosen destination with any degree of accuracy. Distance/time in FTL is also constrained by power availability. Long trips use more power. There is always a delay in setting up a jump so upon arrival at point X Y amount of time is required to calculate a new jump and 'power up' or some such techno babble. Lastly there are limitations (most people use gravity wells ) on how close to a star you can arrive.

  2. While there is FTL travel there is no FTL communication or if there is its limited due to power constraints and distance etc to a very low bandwidth. So ships may be able to ‘text message’ home but not much else. The only other way to beat the light limit is to simply send messages through the wormhole network which all ships including FTL capable ones also use when they can because it’s cheaper/easier.

Within these constraints the following would be my answers to the points you raise.

  • While the volume of a solar system is impossible to defend wormholes, planets & stations etc are choke points & therefore they can be ringed by defenses.
  • You might not be able to defend an entire solar system, but you can use space-based sensors to scan it! (If it hasn’t already been mentioned stealth is space extremely difficult if not impossible at least or anything other than small specially designed ‘spy’ probes. This is because spaceships are hot and space is very cold. (Think blast furnace in the middle of Antarctica)
  • The above means ships will be detected by defenders. The more ships you have and the larger they are and the quicker that will happen.
  • In light of this and the other limitations you’ve imposed on ship design (delicate, no shields etc) all FTL warships are carriers and operate under similar constraints.
  • Upon arrival in a hostile system they strike a balance between being close enough to their targets to get a strike in asap and far enough away to protect themselves from direct attack on short notice in return. (Or at least they try to within the limits imposed by the FTL drive) They then launch their ‘fighters’ which are unmanned drones equipped with the weapon systems you mentioned.
  • Individual attack ships may not have all/every every weapon on your list i.e. they may be specialized (task specific) or modular (you load them up with what they need for their intended mission) its up to you.
  • The attack ships are unmanned because crewed ships waste space on the all the systems needed to keep the meat breathing and cant pull the Gs an unmanned ship can. Lastly if you lose the battle and have to flee you also lose any crews who cant get back in time to be recovered (which would be most of them).
  • Once they have 'launched' they either maneuver to avoid or delay contact with the enemy as long this possible or leave depending on the threat situation. Remember your carriers will be priority targets for the enemy, they are expensive, and their loss must be avoided at all cost.
  • The carriers themselves only armament will be point defenses systems and decoys etc (lasers not gun because mass is expensive, i.e. stuff to protect them from anything fired at them.
  • The only exceptions to the ‘all star ships are carriers rule’ would be exploration vessels, reconnaissance/spy ships and perhaps military support vessels (repair & re-supply ships etc)
  • If the carriers are forced to flee there may be smaller reconnaissance ships that have entered the system some distance from the fleet whose job is to monitor the battle and or take over control in the event the carriers have to flee. Solar systems are huge so a widely disbursed group of watchers will take time to get to/weed out. If the carriers have the time/capability they can perhaps jump back into the system somewhere else later on. (It's up to you - remember there was no guidance on the limitations of your FTL drive.)
  • You could perhaps have FTL troop transports but basically if you win the battle you'll control the wormhole junctions anyway so they may be redundant. (And using them is, as I said cheaper and easier than using FTL.)
  • Finally in a large battle you might want to deploy manned ships to control specific groups of fighters and co-ordinate the battle a close range. But if you lose they’re dead or in prison, so volunteers only perhaps?

EDIT: you might be able to have other classes of warship is you want but given how fragile they are your options are somewhat limited. You could for instance create a class of missile cruiser, perhaps smaller than the largest carrier class but almost entirely armed with missiles. They could act independently or in task forces with carriers but regardless their role in a pitched battle would be to 'launch and run'. Unlike the carriers they would not have any vessels to recover so once they're fired off all their magazine, there's generally no point in having them hang around unless some pressing reason crops up.

Lastly, the reconnaissance vessels I referred to could perhaps be referred to as Destroyers. They would be smaller ships with limited armament. (Although their role would be more like that of subs during the pacific war than escorts.) They can jump into systems as part of a fleet to scout/monitor battles, or separately just to spy/launch reconnaissance probes. But they would also have enough payload capacity to carry a limited number of missiles instead of probes (or a combo of both) and could perform commerce raids or strikes on isolated targets of opportunity as they jump from system to system.


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