In speculative fiction, a force field, sometimes known as an energy shield, force shield, force bubble, defence shield or deflector shield, is a barrier made of energy, plasma, or particles. It protects a person, area, or object from attacks or intrusions. This fictional technology is created as a field of energy without mass that acts as a wall, so that objects affected by the particular force relating to the field are unable to pass through the field and reach the other side. This concept has become a staple of many science-fiction works, so much that authors frequently do not even bother to explain or justify them to their readers, treating them almost as established fact and attributing whatever capabilities the plot requires.
History
The concept of a force field goes back at least as far as the 1920s, in the works of E.E. 'Doc' Smith and others; in William Hope Hodgson's The Night Land the Last Redoubt, the fortress of the remnants of a far-future humanity, is kept safe by something very like a force field. In Isaac Asimov's Foundation universe, personal shields have been developed by scientists specializing in the miniaturization of planet-based shields. As they are primarily used by Foundation Traders, most other inhabitants of the Galactic Empire do not know about this technology. In an unrelated short storyBreeds There a Man...? by Asimov, scientists are working on a force field, capable of protecting the population in case of a nuclear war. The force field demonstrated in the end is a solid hemisphere, apparently completely opaque and reflective from both sides. Asimov explores the force field concept again in the short storyNot Final!. The concept of force fields as a defensive measure from enemy attack or as a form of attack can be regularly found in modern video games as well as in film, such as in The War of the Worlds and Independence Day. The ability to create a force field has been a common superpower in comic books and associated media. While only a few characters have the explicit ability to create force fields, it has been emulated via other powers, such as Green Lantern's energy constructs, Jean Grey's telekinesis, and Magneto's manipulation of electromagnetic fields. Apart from this, its importance is also highlighted in Dr. Michio Kaku's books.
A barrier allowing workers to function in areas exposed to the vacuum of space. The atmosphere inside would be habitable by humans, while at the same time allowing permissible objects to pass through the barrier
A walkable surface between two points without the necessity of building a bridge.
An emergency quarantine area to service those afflicted by harmful biological or chemical agents
A fire extinguisher where oxygen is exhausted by the use of a space confined by a force field thereby starving the fire
As a shield to protect against damage from natural forces or an enemy attack
As a deflector to allow fast spaceships to traverse space without colliding with small particles or objects.
A temporary habitable space in an area otherwise unsuitable for sustaining life
The capabilities and functionality of force fields vary; in some works of fiction, energy shields can nullify or mitigate the effects of both energy and particle and conventional weapons, as well as supernatural forces. In many fictional scenarios, the shields function primarily as a defensive measure against weapons fired from other spacecraft. Force fields in these stories also generally prevent transporting. There are generally two kinds of force fields postulated: one in which energy is projected as a flat plane from emitters around the edges of a spacecraft and another where energy surrounds a ship like a bubble.
