Just how unrealistic is the technology we see in sci-fi novels and television shows? In Physics of the Impossible (2008), renowned physicist Michio Kaku takes a mind-bending look into how far away we really are from such fantastical notions as starships traveling faster than the speed of light or teleporting to different planets.
Remember the force fields used in Star Trek? Formidable energy barriers that protected starships from rockets and enemy fire? The stuff of fantasy, right? Actually, force fields are known to classical physics.
As we know, many objects can exert an influence over other objects in their vicinity without direct contact with them. For instance, a magnet attracts or repels things that lie within a certain field around it. In the nineteenth century, a British scientist named Michael Faraday came up with the concept of force fields, invisible areas or lines of force that envelop a magnet. Later, the concept expanded to include other forces, such as the earth’s gravitational field.
Sure, these aren’t the force fields we know from science fiction, but they could help us create them. It might even be possible to develop force fields that deflect rockets.
Here’s how: When gas is exposed to extreme heat it becomes plasma, an electrically charged mass that’s neither solid, liquid nor gas. This plasma could then be molded by magnetic and electrical fields to form an invisible sheet or plasma window. This force field could then be reinforced with a lattice of carbon nanotubes: nanoscopic cylinders made of thin, rolled-up sheets of carbon. Carbon nanotubes are stronger than steel and could deflect rockets.
But what if you wanted instead to deflect someone’s attention, say, with an invisibility cloak? This, too, isn’t impossible!
Our ability to see depends on the light that objects reflect. The more light that passes through a material rather than being reflected by it – such as what happens with a gas or liquid – the less visible the material. But there’s another way that things can become invisible: in 2006, scientists at Duke University developed composite materials known as metamaterials that contain small particles which deflect as opposed to reflect light waves. Any objects enveloped in such material are virtually invisible.