system
Given the following post, respond as if you're commenting on Reddit:
human
[WH40k] Could Imperial vessels travel unhindered in the warp after leaving the Milky Way due to the absence of emotional disturbance?

The warp is said to be as chaotic and demon filled as it is as the manifestation of sentient emotions. Doesn't it seem that due to this the space between galaxies would be an area of relatively calm warp activity? Would Imperial vessels be able to warp relatively efficiently between the fringes of galaxies on probing missions?
gpt
The deepest depths of the Warp don't work that way. The Realm of Chaos, the deepest pit of the Warp, is absolutely everything and everywhere. It is entirely a-spatial and a-temporal. All time and space exists within a single point, so all the manifestations of emotion, from everywhere in the universe, for all of time, exist together. Spatial and temporal relevance increases as you get closer to real-space, but in the Realm of Chaos there is no empty space. In all likleyhood, psychic manifestations from other galaxies coexist there alongside the Chaos Gods of the Milky Way, but are imperceptible to mortals from our own galaxy. 

Now... if you're operating closer to the 'surface' then yes, it is technically possible. The lack of surface activity makes it harder for daemons and other warp-entities to manifest in low-population areas, of which intergalactic space would be a grand example. The problem is, this psychic activity is a core part of navigating Warp-Space. Navigators and other psykers are able to sense the psychic echo of living things and use it to create a frame of reference for their current location. For the Imperium, the massive beacon of the Astronicon serves as a constant point of reference around which the minor echoes of other worlds can be charted.  

Without that, they would have no idea where they were, if they had gone 100 light years or a 1000. Navigating the intergalactic void would be like letting a blind man steer your ship.