The founding subject: whether travel through time is physically possible, logically coherent, and what follows if it is.
What belongs here
How it could work — wormholes, closed timelike curves, tachyons, Tipler cylinders, the machines on paper and the ones in garages. Whether it’s coherent — the grandfather paradox, Novikov, bootstrap loops, what time even is. And what follows — predictions, timelines, divergence, what you’d do with it.
What doesn’t, and where it goes
A claim to have done it goes to Wildcard Line. Titor goes to john-titor. Physics for its own sake — black holes, quantum mechanics with no time-travel angle — goes to Science. A time-travel film goes to Screening Room.
House position
The Mandela Effect shelves here, under Time Travel > Speculation & Scenarios. We read it as a worldline question.
How to post here
Pick the sub-shelf by what kind of thread it is. Mechanics & Theory is how. Paradox & Philosophy is whether. Speculation & Scenarios is what if. Add at least one Subject tag.