Homeline is an alternate Earth which differs from our own world in that parachronic technology was invented in 1995. Homeline has since gone on to explore (and exploit) a variety of other Earths, and has become involved in a cross-time war with Centrum. Homeline is the default point of origin for Player Characters in the Infinite Worlds setting.
Centrum is located three quantum levels away from Homeline, and as such the two worlds cannot directly send travelers to each other. As a result, both parties fight out their war in the Quantum 6 in-between (and to a lesser extent, in the Quantum 7, as Centrum is attempting to shift Homeline Quantum 6 echoes towards itself. Homeline, which has a poorer understanding of cliodynamics, and is thus less likely to know how to shift worlds out of Centrum reach, is much more circumspect in this regard, but has shifted worlds to new quanta - either accidentally, or by trying to undo Centrum actions.
Homeline is the home base of the Infinity Patrol, the organization which is chartered by Homeline United Nations to explore and supervise the other Earths. Infinity Patrol has (officially) a monopoly on the parachronic technology.
Homeline is located on Quantum 5.
Technology level: TL8-9 (parachronics TL7^)
There are enough differences between the Homeline of GURPS Time Travel and the one of GURPS Infinite Worlds (including the realities each knows about) that they can be considered different realities. Homeline-2 is the Homeline of GURPS Time Travel and is similar to but not 4e's Homeline's past.
Alpha is a proto version of Homeline that also had actual time travel and a limited WWIII in 1992.
- B523-525, 535-541