Interstellar Travel

In general, there are only two ways of getting around the galaxy: starships and wormholes.

Starships can now travel very close to the speed of light, making even long journeys seem to last only a few months or years for the passengers. Unfortunately centuries pass in the rest of the universe, making long trips a ticket to the remote future. Wormholes are fast, and there is no need for a full starship, just a reasonably fast in-system ship and enough funds to pay the necessary tolls.

The wormhole network is the backbone of any interstellar civilisation. Without it even a close cluster of inhabited worlds would be impossible to keep unified. The main civilisations have all interconnected their networks, creating the Wormhole Nexus - which is often used as the term for "all civilised worlds". There are also some unlinked wormhole networks (one of the best known is the Efficiency Maximization Paradigm network).

Travelling from one place to another is usually quickest through the wormhole nexus, which means that the only relativistic journeys that have to be undertaken are the ones to and from the nexus, often cutting travel times by several millennia. Even then, few people want to leave their own time and culture for the far future.

Expanding the wormhole nexus takes time, since new wormholes are difficult and expensive to build, and have to be transported from the systems where they were created to their destination systems. These trips take the usual years, decades or centuries.

The discovery of several alien wormholes has been an important factor in several regional interstellar expansion efforts, as they allow major jumps outwards without having to wait for the relativistic linelayer-ships to emplace wormholes. However, these also have their own risks, including regional space-time instabilities (due to decay of exotic matter over time) and the possibility of surviving and unpredictable pico- or femtotech AIs.

During the earliest centuries of expansion most wormholes were linked directly from the capital world to the colonies, making transports very quick and government efficient. Over time it was found that this also made the empire vulnerable - if an enemy could infiltrate or attack the capital, they could easily disrupt the contact to many, possibly all, colony worlds. Over time, and especially since the Version War, a tree-like structure instead has emerged, with a network branching out from a root at the capital, with occasional cross-links in order to prevent cut-off operations.