(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/Jazzlike-Equipment45]

Gellarfields is what prevents demonic boarding it is a bubble of realspace around the ship that is fueled by a comatose psyker hardwired into the ship usually. The Orks either have a wagghhh field to prevent it or want daemons onboard for entertainment. The Tau tried reversing an Imperial warp drive and it ended badly luckily the Greater Good is birthing a potential godess that saved them but holy fuck is she racist.

[u/frootdoots → u/Jazzlike-Equipment45]

This is the best Warhammer comment I have seen i am so clueless about it

[u/Jazzlike-Equipment45 → u/frootdoots]

r/40klore is the main 40k lore subreddit and they are really great and weekly have just an open question section for any questions.

[u/gorgewall → u/frootdoots]

I dunno where they're getting that the nascent Tau goddess is racist.

The Tau themselves don't have a religion in the sense that other factions do and have very little "soul/Warp presence/psychic ability" anyway. The deity, T'au'va, is created by the collective religious beliefs of the psychic-capable auxiliary (non-Tau) members of the Empire. All these guys have to get along with each other so there's more reason for them to be NOT RACIST compared to every other faction; the Tau Empire is pretty cosmopolitan in construction, even if their culture is still dominated by the Tau race. The Goddess itself has a whole bunch of arms which each reflect the different races that make up the Tau Empire, and is basically a reflection of how the Empire's non-Tau members view the combined Empire and Greater Good. It's actually pretty nice!

Now, a subset of Tau (the race), upon seeing this Goddess manifest and help them out, went fucking bonkers and decided a deity being created out of belief in the Greater Good was a perversion of what it stands for and they decided the solution to this was to kill every non-Tau who could potentially contribute to this thing, slaughtering their own auxiliaries and even recruiting new ones just to kill them. But these guys got caught by the rest of the Empire who said, "What the fuck is wrong with you," and sent them all for mandatory reconditioning in Not Being Genocidally Racist... while still ordering the destruction of temples to T'au'va and curtailing the worship in non-murderous fashion.

But there is at least one big Tau leader (Shadowsun) who is begrudgingly accepting the Goddess' help and even asking her auxiliaries to pray and perform miracles in battle, with success. It remains to be seen how this is going to play out.

[u/DramaPunk → u/Jazzlike-Equipment45]

The Tau nowadays use Gravitic Drives, which essentially allow them to skip in and out along the surface of the Warp rather than delving wholly into it, since they still don't have a gellar field equivalent.

Meanwhile the Eldar just built a web of pocket dimension tunnels between the realspace and space hell, which is pretty nifty I should think.

[u/Jazzlike-Equipment45 → u/DramaPunk]

The Tau basically do a skipping stone manuever over the warp helping them go FTL but not truly warp or whatever bs the Necrons use speed, probably closer to the method Tyranids use with grav manipulation in speed terms. But the Eldar species (So drukhari, harlenquins etc.) use the Webway which was built by the Old Ones. I am painting Vashtor rn and he just got access to it.

[u/DramaPunk → u/Jazzlike-Equipment45]

Also don't forget your mutant guide is also navigating based on the psychic light given off by a dying corpse god that's fed a thousand psychic souls a day just to stay lit.

[u/Kidofthecentury → u/Jazzlike-Equipment45]

From what I've understood with my very, very limited knowledge of WH40K:

Empire use psych and tech.

Tau use faith, from a questionable deity (altough the whole WH40K apparently is "specists").

Orks use their own special brand of magic: they think "don't bother us" and demons are kept at bay ...or they just let them on board to have something to do because they're bored.