Warhammer 40,000 and Time Travel

[Jaepheth]

As far as I know there's nothing to support this (not that I'm some sort of expert to begin with), but my theory:

When you enter the warp you cease to exist in this universe, and thus cease to exist as a space-time event (matter). Within the warp you exist only as an information pattern (I like to fantasize about warp "formatting" weapons that disrupt patterns/entities by "crystallizing" the warp). Exiting the warp, you are basically recreated at some other space/time coordinates; born of the warp. So if you emerge "before" you entered and kill yourself, you don't create a paradox because an "outside" observer would just see an entity born of the warp terminating a similar entity. So it's sort of akin to the parallel universe time-travel loophole where you never go back to the same universe twice?

If that makes sense.

[Purple]

And having a ship with no crew is a recipe for disaster. You're talking either automation, the problems with which Simon has pointed out, or simply... no crew. Which means that things don't get fixed-- these ships are hundreds of years old, if not millennia in general, something always needs fixing-- and if you run into trouble, you don't have anybody to help you. And it's 40K; trouble always happens sooner or later.

Which would explain the 20% loss rate. Problems happen and no one fixes them until they just happen and it's all over.

[Eternal_Freedom]

Isn't that circular reasoning? We lose 20% of ships, so we'll not bother fixing anything, and that's wy we have such a high loss rate.

[Lord Revan]

that's the imperium for you and that's assuming that all of those 20% was actually truly lost in the warp and not "lost" in the red tape.

[Simon_Jester]

One, many of these ships are presumed capable of operating around places that aren't Forge Worlds and lack the industrial assets to maintain a ship that cannot take care of itself.

That is not really so much of a problem as an asset in this case. If your ship can only be maintained on a forge world than the crew numbers drop even more as you only need to take it to the forge world for maintenance.

Except if you need to maintain a critical system, you may not have the luxury of flying back to a critical system and gambling that it will continue to work.

Or in context of a 10-20 flight lifetime cycle you might not ever have to maintain it at all. If something breaks that's fine. The ship won't last you that long anyhow. Just as long as the engines and geller fields still run you are fine.

A ship that cannot be maintained will inevitably break down faster than one that can.

Two, in the Imperium equipment is a lot more expensive than manpower as a rule, so you don't make a ship cheaper by replacing a large crew with automatic systems. More efficient, maybe, but not cheaper.

I was not really talking as much about automatic systems as no systems at all.

The ship will need to have a variety of systems just to function (navigation hardware and software for sidereal space and possibly for the warp, a large number of engines including manuvering thrusters, a reactor, systems to distribute power throughout the ship, life support for crew operating all of the above, and so on).

A box with an engine just can't do many of the things you need a freighter to do.

A merchant ship would (you're right about this) be a lot simpler mechanically and leaner-manned physically than a warship of the same size. But there are limits, and it doesn't get around the point that it's very hard to design a ship that is so cheap that it can pay for itself in ten voyages. Especially for a bulk cargo carrier.

I am not sure about that last bit. Say you basically take a shipping container, geller field and some engines. That's your merchant ship.

What makes you think you can even pay for the engines and Gellar field in ten trips?

If you cut down on the crew and thus life support you can keep 99% of the ship without any. Which means it probably does not even have to be pressurized if you have sealed cargo crates. If something breaks you just don't fix it until the ship is so worn out that it gets lost in the warp. Rinse and repeat.

This results in a lot of ships getting lost faster than necessary if they were properly maintained.

And even if that condition applies to your ships, people should act that way. When travel is that dangerous, you don't have a class of professional merchant sailors/spacers, you have people who are doing it for a few voyages to make enough money to be set for life. You don't have ancient ships that have seen better millenia, you have ships being constantly built in huge numbers to replace the ones that are lost. You don't have massive quantities of bulk goods moved across stars, because nobody in their right mind would risk death just to move grain or a pile of rocks.

In the case of merchant ships they might not have a choice in the matter. What are they going to do after all? Refuse and be executed?

Except that trade is by nature a voluntary undertaking. There are plenty of people in Imperium space who participate in interstellar journeys voluntarily- pilgrims, traders, and so on. They're not all conscripts and you know it.

[Optimus Metallus]

Yeah, both Terra and Macragge at least have thriving pilgrim/tourist industries, which sounds funny to say when talking about the 40k universe.

[bilateralrope]

Maybe the 20% of ships lost are mostly ships that weren't put together properly. So something breaks and the ship is lost. But if a ship survives enough trips along a safer route, that's considered proof that it's put together correctly. So it gets transferred to a route that is less safe, but has a much higher rate of successful travel because only proven ships attempt it.

[Simon_Jester]

In other words, 20% of all ships are lost because 20% of them are built the way Purple would build them?

[Lord Revan]

Yeah, both Terra and Macragge at least have thriving pilgrim/tourist industries, which sounds funny to say when talking about the 40k universe.

and they're not the only ones either there's shrine worlds that have their economy built around pilgrims Kathur for example (Spoiler

well before kathur was destroyed By Typhus the Traveller at least

[PainRack]

Well, it would make sense that military ships and perhaps Rogue Trader craft that could afford it can pack a better quality of Gellar field. We see the same pattern elsewhere-- Space Marines and Inquisition get the best gear of all, Imperial Guard are a step or two (or three, or ten...) down, and Planetary Defense Forces are lucky if they have more than two guys capable of marching in a straight line while holding a lasgun (exaggeration for dramatic effect).

It would make sense to me that military craft might have redundant Gellar fields-- if one fails, the others are still up. A tactic that civilian craft might not use on various pretexts-- they need the space for cargo or passengers, they don't do long jumps, the Emperor will watch over them, etc.

So it doesn't stand out as particularly odd to me that civilian ships might suffer a greater rate of Warp attrition than Guard transports or Navy battleships. Things do almost always go ploin-shaped when the Gellar field fails, regardless of who's on the craft.

I always consider that traders like the Chartist captains don't have 'real' navigators and that they might exist an entire subclass of starship captains who navigate using the same techniques that other races use. Computed and sensory equipment rather than the psychic beacon of the Astronomican....

It handwaves away the difficulty of ensuring a Navigator for every starship.....




Odd. I think the web ate up an earlier post.

But given the existence of warp currents speeding journeys, found as far back as 2nd Edition and lastly in Battlefleet Kronus, I always wondered whether the time dilation effect of the warp has any relationship with Warp speed. As in ships that travel faster in the warp experience different time dilation effects......

[Simon_Jester]

Perhaps faster apparent Warp travel is actually just a consequence of greater time dilation...

No wait, that can't be right. Time dilation affects the ratio of time passed by your ship's clock and by an outsider's clock. Your speed could still be consistently measured in terms of how long it takes you (by your onboard clock) to go between two points. So there has to be a definition of 'speed' independent of how long it takes you to get from A to B in the eyes of an outside observer who stays in sidereal space.

[Lord Revan]

you got remember that when it comes to the Warp normal rules of physical space are more suggestions then anything else so you really can't draw on them too heavily indeed there's very few if any "hard" rules about the Warp.

[andrewgpaul]

Well, it would make sense that military ships and perhaps Rogue Trader craft that could afford it can pack a better quality of Gellar field. We see the same pattern elsewhere-- Space Marines and Inquisition get the best gear of all, Imperial Guard are a step or two (or three, or ten...) down, and Planetary Defense Forces are lucky if they have more than two guys capable of marching in a straight line while holding a lasgun (exaggeration for dramatic effect).

It would make sense to me that military craft might have redundant Gellar fields-- if one fails, the others are still up. A tactic that civilian craft might not use on various pretexts-- they need the space for cargo or passengers, they don't do long jumps, the Emperor will watch over them, etc.

So it doesn't stand out as particularly odd to me that civilian ships might suffer a greater rate of Warp attrition than Guard transports or Navy battleships. Things do almost always go ploin-shaped when the Gellar field fails, regardless of who's on the craft.

I always consider that traders like the Chartist captains don't have 'real' navigators and that they might exist an entire subclass of starship captains who navigate using the same techniques that other races use. Computed and sensory equipment rather than the psychic beacon of the Astronomican....

It handwaves away the difficulty of ensuring a Navigator for every starship.....




Odd. I think the web ate up an earlier post.

But given the existence of warp currents speeding journeys, found as far back as 2nd Edition and lastly in Battlefleet Kronus, I always wondered whether the time dilation effect of the warp has any relationship with Warp speed. As in ships that travel faster in the warp experience different time dilation effects......

Not every ship has a Navigator, IIRC, and they're not necessary for warp travel - only for accurate, safe long distance travel. Shorter routes (tens of light-years, or thereabouts) can be navigated using a sort of "dead reckoning" based on sensor readings, knowledge of local tides and currents and whatnot. The longer the distance, the less accurate those predictions and calculations become, and you need some way of actually reacting to conditions in the immaterium in real time - which is where Navigators come in. Tramp freighters on well-travelled routes with short hops between local star systems can get away without one.

As to the excerpt Kojiro posted, it's described as (part of) an Imperial Navy report - I took the 20% "loss" rate to be those ships which at the time of writing were overdue - not destroyed.

The Navigators are what gives the Imperium its strategic mobility advantage over most of the other races; Orks and Chaos renegades go where the Warp will take them, for the most part. Occasionally, there's some form of divine intervention (like Ghazgkull's escaping destruction as he fled from Armageddon after the Third War). Eldar can cross the galaxy in minimal time - as long as there's a webway portal where they want to go. Otherwise they've got to sneak through the Warp, with the added disadvantage of being really obvious to daemons. Tau sort of scuttle along the boundary really slowly and the Tyranids may be unstoppable, but they're hardly fast.

[Kojiro]

The Navigators are what gives the Imperium its strategic mobility advantage over most of the other races;

Can you imagine the logistical nightmare of trying to organise a military campaign where you have a 1-6 week margin of error for supplies and reinforcements arriving? And that's for a stable area.

[andrewgpaul]

But they can do it at all, that's the point. It also explains why the usual Guard strategy is "overwhelming force". They know the reinforcements might be late or absent, so they try to send as many men as possible in the first place.

[Lord Revan]

I also suspect that for the most part you're sent with supplies for the duration it would take to get fresh ones when you're sent on a mission, as it seems ships and travel relatively close to each other tend enter and exit the Warp at the time and place (granted it's the warp so nothing is certain).

[SilverDragonRed]

But given the existence of warp currents speeding journeys, found as far back as 2nd Edition and lastly in Battlefleet Kronus, I always wondered whether the time dilation effect of the warp has any relationship with Warp speed. As in ships that travel faster in the warp experience different time dilation effects......

Perhaps faster apparent Warp travel is actually just a consequence of greater time dilation...

No wait, that can't be right. Time dilation affects the ratio of time passed by your ship's clock and by an outsider's clock. Your speed could still be consistently measured in terms of how long it takes you (by your onboard clock) to go between two points. So there has to be a definition of 'speed' independent of how long it takes you to get from A to B in the eyes of an outside observer who stays in sidereal space.

Not sure if this helps clarify things, but I found a table in an old copy of White Dwarf 140 dealing with time dilation and warp speed.

Warp Time to Real Time
Minimum
1 ly 2 mins/43 mins
5 lys 7 mins/1 day
10 lys 14 mins/2 days
50 lys 1.25 hrs/1.5 days
100 lys 2.5 hrs/3 days
500 lys 12 hrs/2 weeks
1000 lys 1 day/1 mo
5000 lys 5 days/5 mos

Maximum
1 ly 6 mins/4.5 hrs
5 lys 30 mins/1 day
10 lys 1 hr/2 days
50 lys 4.75 hrs/9 days
100 lys 9.5 hrs/3 weeks
500 lys 2 days/3 mos
1000 lys 4 days/6 mos
5000 lys 3 weeks/3 yrs

[Sea Skimmer]

The 20% loss rate might not be so different, if not lower, then losses on several year long round trips to the orient from Europe in the ~17th century, which is kinda exactly what 40K was trying to invoke with its vision of space travel.

For commerce such a high loss rate is no show stopper, you increase prices and investors would just invest in shares in many different ships, instead of owning 100% of any one ship that might go missing. That's how modern insurance markets got going; eventually the ships got safe enough that things shifted back to single owners and the insurance became divorced from a share of the profits. Back then it was also plausible to make a profit over the construction cost of a single ship on a single trip, even a one way trip, and this could well be true of 40K too. It seems logical to assume that most civilian space cargo is very high value and rare items, with very high profit margins. Otherwise what on earth would you even need to ship from one system to another? Its not going to be shirts and plastic teacups at least. In WW1 the US began building wooden merchant ships on the basis they were economical for one way trips to Europe carrying munitions. A concrete ship program also existed on the same basis, and hell even today I bet a shipload of all Iphones could turn a one way profit without implausible added price.... if the market was captive enough of course as this concept requires. Apple profits suggest this might be true with NO added cost, just less profit.

Does 40K have any giant aliens with giant dugout space canoes made of space trees anyway? Or next codex?

For military operations no specific amount of time actually matters, given proper planning in the first place which 40K hates. You just can't set a fast moving pace of operations. Also this is a strong incentive to combat load all ships with troops and equipment and supplies, and avoid sending any one completely independently (least say men arrive with no ammo). This would be pretty trivial given how big 40K ships can get, and the fact that the target for ground troops would be a specific planet and somewhat understood as an objective. What matters in the end are pure percentages, how big the errors are and what not, as these determine what your margins are going to be. As it was big amphibious operations in WW2 were planned on as much as a 2 year lead time when you look at what it really took to put the forces together. Detail planning was ~6 months lead. But back in the 17th century stuff could take even longer to get going. People would build whole fleets for specific operations, then go off for three or four years in some cases.

[Purple]

But back in the 17th century you had the luxury of taking years to plan things. In 40K travel might not be too swift for anyone. But space is still big. And you can't really expect chaos or orks or who ever is raiding your planet this week to give you several years or even months of advance warning.

[Elheru Aran]

Actually in 40K you *can* take years to plan things. That's the whole thing about the Administratum.

The Kroot do have a space equivalent of dugout canoes in their 'war spheres'.

Civilian cargo traffic in the Imperium... a decent percentage of it is food supplies for the hive worlds. A lot of it is moving material for the Guard-- tanks, ammunition, whatever, although the Guard does have Navy ships seconded specifically to that purpose. Honestly the background is fairly vague on civilian stuff for out-of-universe reasons... all that quadrotriticale isn't going to magically sprout a Chaos cult all on its own. Though there was one case where contaminated grain caused corruption on a hive-world, so there you go, heh.

[Simon_Jester]

But back in the 17th century you had the luxury of taking years to plan things. In 40K travel might not be too swift for anyone. But space is still big. And you can't really expect chaos or orks or who ever is raiding your planet this week to give you several years or even months of advance warning.

Yes, but you can expect to have the luxury of taking years to react to a threat on the strategic level. Your enemies don't travel any faster than you, on the whole.

You can also expect a given Imperial world to fight bravely for a period of time until reinforcements can arrive, so that it's more practical to 'rush' in reinforcements that take a year or two to arrive. If orks hit one of your major worlds, the planetary defense force should be able to at least slow them down meaningfully, in other words.

Plus, communications are faster than travel, so if you rush reinforcements to a sector where world after world is being attacked, you will get steadily better and more timely intelligence on local conditions as your force gets closer. By the time you reach the theater of operations, you'll know where to send your forces to meet the enemy in open battle.

[andrewgpaul]

I think the only alien race that can count on being able to get anywhere they want to go reasonably reliably, consistently faster than the Imperium is the Necrons.

[Sea Skimmer]

Yes, but you can expect to have the luxury of taking years to react to a threat on the strategic level. Your enemies don't travel any faster than you, on the whole.

And indeed we see large invasion forces like hive fleets getting deep into the Imperium before they can be met by collections of forces large enough to stop them, they are not held at the border. Even then its probably that most of those reaction forces were still somewhat regional, at least on the scale of the Imperium being say, three or four radial regions. The very need to defend it would preclude calling too many forces from the far reaches, since they'd not only take so long to appear, but so long to return to their original positions.

On the other hand it also doesn't appear that the Imperium is at the level of building specific fleets in real time reaction to invasion threats, but that might have more to do with how little they understand their own technology and how highly mobilized they already area, then it being implausible for it to be done.

All you'd need is crews willing to risk death, and that wasn't a big deal in real life, shouldn't be here either when you can get stokers out of giant hive sewers or something.

For commerce, feeding a hive world shouldn't require Imperium spanning missions either, its bound to be a more hub and spoke approach with fractional transit distances. Otherwise the shit would make no damn sense in the first place, of the Hive worlds ever even existing and being rather numerous as far as I can tell.. Those ships might have lower loss rates then ones going from one literal end of the empire to the other to bring in the latest Garm Five LuxuryBat Silkskin gloves, or some such exotic irreplaceable good. That's the kind of place where ships might really be built to make one trip, have a 20% chance of loss, but a 100% profit margin so that arrival of 4 out 5 still means an 80% profit on the enterprise.

[Simon_Jester]

On the other hand it also doesn't appear that the Imperium is at the level of building specific fleets in real time reaction to invasion threats, but that might have more to do with how little they understand their own technology and how highly mobilized they already area, then it being implausible for it to be done.

Mostly the latter- they're already building new warships as fast as they know how given the limits of their infrastructure and technical personnel, so all that changes in response to a specific threat is that new ships are sent to deal with that threat, rather than being sent to fill random holes in random tables of organization.

[SilverDragonRed]

I think the only alien race that can count on being able to get anywhere they want to go reasonably reliably, consistently faster than the Imperium is the Necrons.

There is also the Eldar with their Webway Portals. The GEoM had a plan to phase out warp-capable craft and the Navis Nobilites (Navigators) with a human made webway because how of reliable and fast that system is.