Chapter 2: Invisibility - Class I

Is such an idea really possible? Invisibility is a concept so far-fetched, that when we see it happen in movies or in books, we feel cheated on by the directors and authors. From Harry Potter's invisibility cloak, to the powerful ring in The Lord of the Rings, many people with the slightest background in physics know that invisibility defies the Laws of Optics and Maxwell's Equations. However, science works in marvelous ways and today, we find ourselves stumbling across substances called metamaterials.

These metamaterials may very well be the substances that re-write textbooks on optics due to their distinct properties not found in nature. They are created by bedding tiny implants within a substance that force electromagnetic waves to bend in unorthodox ways. In optics we deal with a concept known as the index of refraction. For example, a narrow beam of light bends when it enters glass and then keeps going in a straight line. But assume we were able to control the index of refraction so that at every point within the glass it could change. As light would move through this new material, it could bend and meander in new directions, a path that would resemble that of a snakes. If the index of refraction inside a metamaterial could be controlled so that light could pass around the object completely, the object would be invisible. For this phenomena to occur, the metamaterial must have a negative index of refraction, which according to almost every physics textbook made, is an impossible feat. In 1967, Soviet physicist, Victor Veselago theorized in a paper that metamaterials have "weird optical properties, such as a negative refractive index and reversed Doppler effect." Metamaterials were once thought so bizarre that they were thought impossible to construct, however, in recent years, they have actually been manufactured in the laboratory, forcing reluctant physicists to rewrite the book of optics.

If this new substance can be produced to keep a constant negative index of refraction, scientists might have something to really work with in the future. The first country to posses the power of making objects invisible, will reign supreme over the rest of the world. The element of surprise and the ability not to see an enemy is the most lethal power to ever be sought after.