As the space ship in the 1986 film Aliens moves towards a mysterious planet, the cosmonauts aboard
gaze suspiciously at the foreign body with their feet firmly pressed against
the ship’s floor. The sci-fi adventure
has barely begun, and already, the laws of physics have been ignored due to a
common imbalance in Hollywood: too much fi,
too little sci.
I want to be clear about something: I am an avid fan of
science fiction movies, whether or not they are set in space. In fact, I was thoroughly entertained by Aliens, the sequel to Alien - so much so that I watched it
recently for the second time.
As the film is set in the distant future, it is sensible
that several technological leaps have been made by mankind. I am comfortable with the intelligent robot
that is a part of the crew. I am intrigued
by the sensitive motion detection equipment that they use. What makes me queasy is when the most basic
law of motion is inexplicably defied.
When advances in technology occur, they lead to more robust
tools. However, these tools, no matter
how fantastic they are, must operate within the constraints of the universe. Otherwise put, technology is dynamic, but
exists within an operational framework that is static.
When a space travelling Sigourney Weaver stands up on the
surface of a ship, this implies that there is a set of contact forces between her
feet and the surface. A force, commonly
referred to as the normal force, is
pushing up onto her feet. Unless you are
currently undergoing a vertical loop on a jet airplane, or happen to be reading
this article while in a space orbit, the normal force is currently acting on
you.
