Steins;Gate's "power system" is time travel theory — specifically the concepts of World Lines, Divergence Numbers, and attractor fields. Understanding these is key to understanding the story.

World Lines & Divergence Numbers

Each timeline in Steins;Gate is a "World Line" — identified by its Divergence Number, a decimal value representing how far it diverges from a baseline. A divergence of 0.000000% would be the original, unmodified timeline. Even a tiny change creates a measurably different world line.

The Phone Microwave — D-Mail

Okabe's lab accidentally creates a device that converts text messages into data that can be sent to a mobile phone in the past. These "D-Mails" change the recipient's past behavior, creating timeline divergences. The device requires extreme energy (it uses a nearby particle accelerator as a power source without knowing it).

Attractor Fields

The most important concept: certain major events are "attractors" — they happen in almost every timeline regardless of changes. Mayuri's death, SERN's dystopia, Kurisu's death — these are attractors. The series is about finding the specific divergence point where ALL bad attractor fields can be avoided simultaneously. This is the "Steins Gate" world line.

Okabe's Reading Steiner

Okabe has a unique ability called Reading Steiner — when a timeline changes, he retains memory of the previous world line. He is the only person who experiences timeline changes consciously. This is both his greatest power and his greatest burden.