What is the scientific basis behind "shield" technology in future/space shows?

[Mark]

What is the scientific basis behind "shield" technology in future/space shows?

Is this something that can actually be developed? Where did the idea of some kind of electric or magnetic or whatever shield come from? With a deadly layer of high speed space debris accumulating around our Earth right now, I wonder if we'll ever be able to get off of the planet without developing this shield technology.

Is shield technology something that can theoretically be developed? And if so where can I read about the theories behind it?

Thanks
@ Well unless anyone else has any input I'll take your word that it's purely fictional. I proposed this question because I've only taken a foundational level of physics and I couldn't figure out how force fields could be possible from what I know.
But so many other future technologies show up based upon some tidbit of scientific theory that I wonder if there is some small theory that compelled this. Recently laser weapons have been developed though not in the way depicted in the SF world, and I even recently heard of a device that can send a particle through a directed beam and construct simple microscopic structures (Which may become in a few centuries the technology to build larger structures/objects like in Starcraft or like the food generators in Star Trek) So, though surely over-dramatized in SF shows, I was just curious if there was any theoretical basis for force fields.

 

[puregenius_91]

Mark, The best resource you are looking for is well... not yet written.
The shield that you see in space show is, as of today, fictional. It can absolutely not exist. At least none that can be applied to any general particle in space or on earth. It may be possible for magnetic materials. How? well, assume this shield was created of "layers' of magnetic 'sheets' with each sheet having opposite polarities. Now when some unmagnetized object (say an iron bullet), but which is made of magnetic material, enters the first sheet, it is induced with a polarity opposite to that of the first sheet's magnetic direction (let's just assume it is north). But when it reaches the next sheet, it would be repelled, because the sheet would be north, and north magnetic field would repel the north facing bullet.

This is in theory, possible. if you had a strong magnetic field. The same can be applied for electrically charged particles... say protons, electrons. But for a neutral, nonmagnetic atom (which is what most of the world is made up of) there is no known way of creating a 'force field'. The reason lies deep in quantum mechanics, and the constraints on the energy of a particle in a potential field.

These are just my thoughts, they don't necessarily have to be right, but it should give you something to think about.