overthinkingit writes "A scientist has tried to apply serious math and physics, including the Law of Cosines, to analyze how the DeLorean in Back to the Future travels through both Time AND Space: 'in order to pull off the kind of time travel we see in the Back To The Future trilogy — the kind where the traveler is transposed in time, but remains stationary in the same relative position to where he/she left — the DeLorean would have to be an outstanding space ship, in addition to its already laudable work as a time-ship. According to Doc Brown's stopwatch, Einstein the dog travels precisely one minute into the future on this first jump, arriving, relative to their frame of reference, at the same location he left. But how far has this reference frame itself traveled during that one minute?'"
If it happens once, it's a bug. If it happens twice, it's a feature.
If it happens more than twice, it's a design philosophy.