Blinovitch Limitation Effect
The Blinovitch Limitation Effect is the effect or non-effect of crossing timelines.
Named after Aaron Blinovitch who formulated the Blinovitch theory in a reading room in the British museum in 1928 on Earth. (MA: The Ghosts of N-Space)
Theory A
The limitation effect limits the amount a person can change their time line, in fact any changes which deviate create a time loop. (DW: Day of the Daleks)
Theory B
The effect is the energy released when crossing your own timeline and interacting with a past (or future depending on perspective) and the energy thus released. (DW: Mawdryn Undead)
Theory C
The Limitation Effect stops a time traveller from messing around with their own personal timeline. The limitation effect is a precursor to a paradox (probably). (DW: Day of the Daleks)