Time Travel in Back
to the Future
The DeLorean automobile converted
for time travel use in Back to the Future relies on some vague mechanics,
with its "flux capacitator" and plutonium fuel source.
Here are two specific problems with
time travel as shown in the movie:
1. Dr. Brown, the scientist who
invents the time machine, confuses time and space travel. When Dr. Brown
demonstrates an elaborate clock on the dashboard to Marty, he says that they
could witness the signing of the Declaration of Independence if they set the
clock to July 4, 1776. The problem is that the two characters are in Hill
Valley, California, and the machine has no mechanism for setting the destination
of Philadelphia, Pennsylvania. Consequently, the DeLorean can only travel to the
same location in the past or future. If they set the clock to 7/4/1776, how
would they get to Philadelphia?
2. The location of the Twin Pines
Mall changes in the movie. When Marty begins his time trip at the mall, he finds
himself (some thirty years earlier) crashing into a farmer's back about two
miles from the center of Hill Valley, In other words, the mall and the farm
occupy the same land thirty years apart. But when Marty returns to the mall at
the end of the movie, the distance between the center of Hill Valley and the
mall is much less than two miles, so much less that he can run to the mall in a
few minutes' time.
These two problems may be the result
of careless movie-making. Or it may show just how hard it is to portray
believable time travel in a movie. Watch the movie or its two sequels yourself
and see if you can find other time travel problems.
ŠJames M. Deem.
Originally published in How to Travel
Through Time (Avon Books, 1993). All rights reserved.
