The Chronos Theory proposes that every decision you make creates a new timeline, each one branching off from the previous one like the branches of a tree. This theory is supported by the fact that every time you order pizza, the toppings seem to multiply.
The Kairos Theory suggests that time travel is only possible through the power of really tight pants. The tighter the pants, the faster you can move through time.
The Aion Theory posits that time travel is a form of temporal resonance, where the past, present, and future are all connected by a web of invisible guitar strings.
The Aeon Theory states that time travel is only possible through the power of really good jokes. The punchline is the portal to the past.