Scientists are close to developing an invisibility cloak

By Julia Calderone
Ever wish you could just disappear? Turns out this may not be as far off as we thought.

In the past decade, scientists have made huge advances in developing super materials that may one day hide us from the prying eyes of those around us.

And with a little bit of engineering and ingenuity, perhaps it may come in the form of an actual cloak, a la Harry Potter.

But an invisibility cloak doesn't necessarily have to look like a wizard's cape. It could be fashioned out of extremely thin wires made of silica and gold, carbon fibers, silk, or a series of lenses.

There are various prototypes that cloak objects in different ways, but the most promising technique involves light.

As anyone who's tried to feel their way to the bathroom in the middle of the night at a friend's house knows, you need light to see the world around you. In a similar way that a bat uses sonar to bounce sound waves off of objects to discern how far away they are, wavelengths of visible light bounce off objects and back into our eyeballs, allowing us to see them.

When you look at an apple, you can tell that it's red because the fruit absorbs all wavelengths of visible light except for wavelengths associated with the color red. That wavelength bounces off of the fruit and into your eye, where it is then processed by your brain.

An invisibility cloak can sidestep this process by making wavelengths of light bypass an object. In a similar way to how water flows around a boulder in a river, special materials can make wavelengths of light hug around the edges of an object instead deflecting them back into your eye. This tricks your brain into thinking the object isn't there.

Researchers from Duke University were the first to develop "metamaterials" that use rigorous mathematical and electromagnetic properties to conceal objects. These are the most promising materials for inventing an actual cloak.

But the lens approach could be useful for allowing doctors to see through their fingers while they're performing a surgery, or by giving drivers a visual edge by placing it in the blind spot of a car, for example.