force field

[claymore]

In some science fiction movies the alien space ship is surrounded by a force field which renders it indestructable. Is such a thing theoretically possible , or is it just that ......... science fiction?

[MrsT]

Force fields have been created but they are so weak as to be of only experimental usage. The Sci Fi type force field just that, fiction.

[fo3nix]

Most things end up being possible.

A large source of confusion is what a 'field' is in physics, and what it is in sci-fi.

In sci-fi, it's more of a shield.

In physics, it's a concept used when thinking about things that are spread over a volume of space. For example, your radiator has a field around it -- a temperature field. Nearer to it, the field is warmer than where it is farther away. There isn't a precise are where the field is, to block things.

In other areas of physics, like electrodynamics, there is such thing as the force, due to a magnetic or electric field (the Lorentz force, for example). This has the concept associated with it of a 'force field'.

[Teddio]

A magnetic field, suitably shaped, could be made to deflect charged particle beam weapons. It would be no good, of course, against photon beam weapons such as X-ray lasers.

[bazwillrun]

Science Fiction invariably becomes Science Fact, so yes give it time and they will be in common use

[MatydaLover]

This is nothing new. Nature has used a magnetic field to protect the Earth from the Sun's wind for eons.

[jake-the-peg]

Radio was science fiction 100 years ago?

I think you'll find 1907 saw the establishment of the first commercial transatlantic radio service!

Seriously though just saying anything is possible if you wait long enough is a bit daft because anyone can argue that about anything absurd.

I could say one day people will be able to levitate and turn their arms into tentacle by the force of their minds. When challenged I just make the arguments above "anything is possible if you wait long enough".

There are forces and things that feel those forces.

There is Gravity and objects with mass, electromagnetism and objects with charge. etc. etc.

So as Tedio has already said not all forces affect everything. To affect matter - which seems the most common idea of a force field you need to master gravity. It seems highly unlikely that a gravitational field could be constructed to say block a door because of the way that fields disipate and spread out.

The "tractor beam" idea has perhaps a bit more chance but the energy that you'd need to create that sort of a gravitation well is mind blowing and even then concentrating it in a beam is unlikely so you'd probably attract everything in the neighbourhood which you can probably imagine would be bad!