New Invisibility Cloak Closer to Working "Magic"

Rachel Kaufman

for National Geographic News

Published January 28, 2011

Harry Potter and Bilbo Baggins, take note: Scientists are a step closer to conquering the "magic" of invisibility.

Many earlier cloaking systems turned objects "invisible" only under wavelengths of light that the human eye can't see. Others could conceal only microscopic objects. (See "Two New Cloaking Devices Close In on True Invisibility.")

But the new system, developed at Massachusetts Institute of Technology and the Singapore-MIT Alliance for Research and Technology (SMART) Centre, works in visible light and can hide objects big enough to see with the naked eye.
The "cloak" is made from two pieces of calcite crystal—a cheap, easily obtained mineral—stuck together in a certain configuration.

Calcite is highly anisotropic, which means that light coming from one side will exit at a different angle than light entering from another side. By using two different pieces of calcite, the researchers were able to bend light around a solid object placed between the crystals.

"Under the assembly there is a wedge-shaped gap," said MIT's George Barbastathis, who helped develop the new system. "The idea is that whatever you put under this gap, it looks from the outside like it is not there."



Invisibility Cloak a Boon for Drivers?
The new invisibility cloak still has its drawbacks: For one, it works best under green light. The researchers designed the cloak this way because the calcite can only be configured for a very narrow wavelength of light, and human eyes are most sensitive to green, Barbastathis said.

(Related: "'Electromagnetic Wormhole' Could Make Objects Invisible.")
In addition, the cloaking effect works only if you look at the hidden object from a certain direction. Viewing the object from another angle will make it "reappear."
Also, the system can only cloak objects that fit under the mineral wedge, which in this case is just two millimeters tall. Still, a larger piece of calcite should be able to hide larger objects.

Barbastathis is confident that his team or another group will come up with a true, three-dimensional invisibility cloak soon. In the meantime, he can think of at least one practical application from the system as it stands. (Also see "Acoustic 'Invisibility' Cloaks Possible, Study Says.")

"I live in Boston, and in Boston a lot of streets converge at very sharp angles, so when you look at the traffic light, it's confusing whether you're seeing the traffic light for you or the light that is for the other street," he said.

With the current cloak, "you could hide certain lights from drivers so they do not get confused."

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Sex enters robotics age

"Good morning, I'd like the 3-KPO-3XC, please!" "Is that the full 144-hour 3CX model sir or just the normal dateline 2-hour plug-in?"

This conversation may not belong to the too distant future. Research work by Terrence Aym* "Scientists predict sex robot partners in coming decades" points towards a not-so-distant world in which mankind cohabits with sexbots.

The idea is not that recent either. Ovid's Metamorphoses bring us the story of Pygmalion, a sculptor who fell in love with his creation. Indeed the idea permeates literature through the ages, culminating in Auguste Villiers de l'Isle-Adam's work, L'Eve Futur, in which a scientist creates a female machine with whom (which?) a British Lord falls in love.

We are reminded that the term robot was coined by the Czech Karel Capek in his 1920 play R.U.R. ("Rossum's Universal Robots"), using the Czech word for "work", "robota". Terrence Aym introduces us to a University of Maastricht researcher into Artificial Intelligence, David Levy, who tells us "My forecast is that around 2050, the state of Massachusetts will be the first jurisdiction to legalize marriages with robots."

Other researchers speak of the Longevity Orgasm as sexbots perfect "sexplosive" devices and sex skills, honed on thousands of years and web-pages of inputs and coupled with near-carnal features. As robotics becomes more advanced, so do robots take on more and more human features, continues the article. For that reason, it would not be far-fetched to envisage a world where humans are head over heels in love with their sexbots.

Real Dolls, for instance, is a company that has been working on female sex androids for over a decade. Levy predicts that Artificial Partners will mimic all aspects of human behaviour and that "the robots humans design and build will become virtually indistinguishable from people. They will mimic humans in every way and some humans will literally fall in love with them, lust for them, and enter into sexual relationships with them".

And not far down the line will be the sexbot arriving twenty minutes late for her wedding with her human partner waiting nervously at the end of the aisle. Let us just hope she does not step on an electric cable, go "POING" and disintegrate before the distraught husband-to-be and his guests, because on her side of the church...
*Scientists predict sex robot partners in coming decades

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