Movies often take artistic license when it comes to well-known physical, chemical, and biological principles, and there are certain stunts in movies that do not resemble the actual occurrences that happen in reality. However, most of these things are hardly noticed by the majority of the public who, truth be told, is there to mostly have a good time and not to nitpick about whether what is depicted could happen in the real world. There are, of course, some limits. You do not want to show something so laughable that will compromise your viewers' suspension of disbelief, but where do we draw the line?
In this post we are going to examine some of things in films that defy the laws of nature.
Decapitation or Brain Destruction
Occurrence: In movies you sometimes find that a character is decapitated, or their brain is destroyed, yet its body nevertheless lingers on in the same position for a few dramatic seconds before falling.
Reality: Maintaining the posture of a body with joints (for example knee and hip joints) against the force of gravity is a continuous second by second task. Upright standing bodies even at rest are maintained this way due to the forces of muscles contracting and pulling against bones. If these muscles were to relax, the body will immediately collapse like a puppet suddenly deprived of its strings. What makes muscles contract is the action of the brain. The brain constantly sends signals through the nerves for the muscles to contract to a greater or lesser degree in order to keep bodies upright and regulate posture. If the brain is severed from the body or is destroyed these signals cease, muscles relax, and the body falls instantaneously to the ground.
Occurrence: When people in movies lose consciousness and fall from a standing position, they never seem to clearly bang their heads or certain areas of their bodies against the ground.
Reality: Falls in real life can be life threatening mostly because of the damage sustained by head impacts. In movies, the actors or their stunt doubles fall in ways that protect the head and other areas such as the tailbone from injury. These “Hollywood Falls” are designed to dissipate the energy of the fall and avoid injury. In the real world, when a person loses consciousness and falls, they cannot maneuver their bodies into the right position to avoid serious damage, especially to the head.
Growth of Mass
Occurrence: Some movies feature an entity or a character that undergoes a transformation which greatly increases their size in a matter of seconds or minutes.
Reality: A living thing cannot just grow to a large size without an equally sizeable input of mass and energy (for example carbon dioxide and sunlight). Any added mass has to come from somewhere. You can’t get something from nothing. Additionally, there has to be a mechanism to generate the extra mass from a precursor, and any such mechanism would presumably require a number of steps and would take time not only to generate the extra mass but to distribute it properly. For example, a type of algae called kelp can use the carbon dioxide in the water to make plant material through photosynthesis, and it can grow in optimal conditions up to two feet per day! This makes it one of the fastest growing organisms on the planet, but still far short of the growth spurts exhibited by some monsters, aliens, or other fantastical entities in the movies.
Explosions in Space
Occurrence: When people within a spaceship witness a large explosion in space, they hear the sound of the explosion and the spaceship is rocked by the shock wave.
Reality: Shock waves are areas of compression of a medium such as air. The explosion pushes air molecules into each other, and that effect propagates to neighboring air molecules and so on forming a shock wave that upon reaching our ears is perceived as a loud sound. The medium of space is not dense enough to propagate the type of shock waves that would rock spaceships and be audible to human beings.
Freezing or Blowing Up When Exposed to the Vacuum of Space
Occurrence: Movies depict people freezing or blowing up when exposed to the vacuum of space without wearing a space suit.
Reality: Because space is largely devoid of mass, two of the three ways by which the body loses heat, conduction and convection, are missing. Heat can then only be lost by radiation. A person suddenly exposed to outer space would not instantly freeze and in fact would only feel mildly cool. Similarly, a person exposed to the vacuum of space will not explode. The air in their lungs would expand causing serious damage if it is not exhaled, and a certain amount of the water in the blood and soft tissues would transition to the gaseous phase (ebullism) which will lead to significant swelling and bruising of the body, but not an explosion. The greatest threat is lack of oxygen which would lead to loss of consciousness in a matter of seconds followed by death.
Groups of Animals Surviving by Preying on Themselves
Occurrence: Some movies show a large group of animals in a deserted or isolated environment that have survived solely by preying on each other.
Reality: This situation is untenable because conversion of energy is not 100% efficient and doesn’t happen at once. Several animals would have to be consumed over the life cycle of a single animal for it to reach maturity and procreate. The new animals would fail to produce a replacement for the animals they have consumed. Each generation of the animals will become progressively smaller until they become extinct.
Humans or Monsters of Very Large Size
Occurrence: In movies, huge beings, many several stories high, are depicted with bodies that are not that different in proportions from the bodies they would have if they were much smaller.
Reality: As bodies change in size, several of their parameters do not increase by an equivalent measure. An increase in body size leads to a much higher increase in body volume, and this creates all sorts of problems. Consider, for example, that a higher volume leads to a higher weight which has to be supported. The reality is that all those colossal beings depicted in the movies with those body plans would collapse under their own weight and also experience a host of other issues affecting things such as regulation of body temperature, blood circulation and aeration, metabolism, etc.
Do any of these differences between the movies and real life bother you? Please leave a comment and let me know.
Image of Godzilla from pixabay is free for commercial use.