Invisibility cloak now within sight: scientists

[Dr Kenneth Noisewater 0]

Invisibility cloak now within sight: scientists

 

The age-old fantasy of making yourself invisible has taken a step toward reality, with scientists saying they have created three-dimensional materials that can bend visible light.

 

For the moment, the vanishing act takes place on a nanoscale, measured in billionths of a metre.

 

But there is no fundamental reason why the same principles cannot be scaled up one day to make invisibility cloaks big enough to hide a person, a tank or even a tanker, the scientists say.

 

The groundbreaking experiments, led by Xiang Zhang at the University of California at Berkeley, were reported simultaneously Sunday in the British journal Nature and the US-based journal Science.

 

Recent advances have created other so-called metamaterials, artificially engineered structures with optical properties that bend light in unnatural ways.

 

But previous attempts had three serious limitations.

 

One was that they only worked on the microwave range of the light spectrum, bending wavelengths much too long to be visible to the human eye. The earlier technology was also limited to two-dimensional systems no thicker than a single layer of atoms.

 

Finally, a large portion of the light was absorbed rather than refracted, a form of energy loss that reduced the "invisibility" factor.

 

The new material, by contrast, produces the negative refractive needed to work within a visible light spectrum and in three dimensions.

 

Negative refraction -- or "left-handed" -- materials deflect light in a way that breaks the standard "right-handed" rules of electromagnetism.

 

Unhindered, light will travel in a straight line. But it will change pathes when it travels from one medium to another.

 

A pencil sticking out of a glass of water, for example, appears to bend slightly starting at the interface of air and liquid.

 

But with metamaterials, light travels opposite the direction it would normally when it hits that interface -- the pencil now seems to bend backwards, out of the water, an optical effect that does not occur in nature.

 

The most immediate application of this new technology will be the construction of special lenses for optical microscopes that can focus on things as tiny as molecules.

 

"There is a significant need in biology to be able to image at high resolution," Jason Valentine, a graduate student at Berkeley and lead author of the Nature paper, explained in an e-mail.

 

The resolution of traditional high-powered tools such as the electron microscope cannot exceed half of a wavelength of light, and have a tendency to cause damage to living cells, he said.

 

"Metamaterials would be a better optical imaging method since it would be non-invasive," Jie Yao, lead author of the Science article, told AFP.

 

But the holy grail of metamaterial research has become the kind of magic shroud of invisibility that has fired the human imagination from H.G. Wells' "Invisible Man" to the adventures of Harry Potter.

 

"In the case of such cloaks or shields, the material would need to curve light waves completely around the object like a river flowing around a rock," Zhang said.

 

"An observer looking at the cloaked object would then see light from behind it, making it seem to disappear."

 

The United States military, which funded the research, is especially keen to develop materials that could usher in an entire new generation of stealth technology.

 

But it isn't going to happen overnight. "To scale up such a material to sizes visible to the naked eye will be very time-consuming and very costly," said Yao.

 

One of the two metamaterials developed by Zhang and his colleagues has a multi-layered fishnet structure composed of alternating layers of silver and magnesium fluoride.

 

"The fish-net structure is counter-intuitive because, as we stack the material in layers, the energy loss is reduced instead of increased," Yao said.

 

Previous experiments has shown that the bulkier the material, the higher the loss.

 

The second material, reported in Science, is composed of silver nanowires grown inside a porous aluminium matrix.

[Park Life 70]

Great perving gear.

[Jimbo 133]

:icon_lol:

[Kid Dynamite 5890]

It'l all end in tears!!!

 

''The Philadelphia Experiment''

 

Several different, at times conflicting, versions of the purported experiment have circulated over the years. The following synopsis serves to illustrate key alleged story points common to the majority of accounts.[2]

 

The experiment was conducted by Dr. Franklin Reno (or Franklin Rinehart) as a military application of a Unified Field Theory, a term coined by Einstein. The Unified Field Theory aims to describe the interrelated nature of the forces that comprise electromagnetic radiation and gravity; although to date no single theory has emerged with a viable mathematical expression.

 

According to the accounts it was thought possible to use some version of this theory to bend light around an object so that it became essentially invisible. This required specialized equipment and sufficient energy. The Navy regarded this of obvious military value and sponsored the experiment.

 

A destroyer escort, the USS Eldridge, was fitted with the required equipment at the naval yards in Philadelphia. Testing began in summer 1943, and was successful to a limited degree. One test, on July 22, resulted in the Eldridge being rendered almost completely invisible, with some witnesses reporting a “greenish fog” in its place. However, crew members complained of severe nausea afterwards. At that point, the experiment was altered at the request of the Navy, with the new objective being invisibility solely to radar.

 

The equipment was not properly re-calibrated to this end, but in spite of this the experiment was performed again on October 28. This time, Eldridge not only became almost entirely invisible to the naked eye, but actually vanished from the area in a flash of blue light. According to some accounts, the U.S. naval base at Norfolk, Virginia, just over 215 miles (346 km) away, reported sighting the Eldridge offshore, whereupon the Eldridge vanished from their sight and reappeared in Philadelphia at the site it had originally occupied, in an apparent case of accidental teleportation.

 

The physiological effects of the experiment on the crew were profound: almost all of the crew became violently ill. Some suffered from mental illness as a result of their experience; behavior consistent with schizophrenia is described in other accounts. Still other members, like Jacob L. Murray, were physically unaccounted for—supposedly they “vanished”—and five of the crew became fused to the metal bulkhead or deck of the ship. Still others faded in and out of sight. Sometimes they disappeared, then crewmates would stick their hands into the spot from which they had disappeared and try to grab the crewmate, but, if they did not, that spot would burst into flames. Horrified by these results, Navy officials immediately cancelled the experiment. All of the surviving crew involved was discharged; in some accounts, brainwashing techniques were employed in an attempt to make the remaining crew members lose their memories concerning the details of their experience.

[Smooth Operator 10]

J69 has spunked in his drawers at the thought of all the grassing he could do, anonymously of course!

[Kid Dynamite 5890]

The amount of attempted jokes at my expense has unfortunately resulted in a huge reduction in the actual humour included in said jokes.

 

You boys need some new material

[Jusoda Kid 1]

Mods, any chance of getting J69 one of these cloaks, his username makes my eyes bleed.

[Smooth Operator 10]

The amount of attempted jokes at my expense has unfortunately resulted in a huge reduction in the actual humour included in said jokes.

 

You boys need some new material

 

I'd have thought you'd be in your element, centre of attention and all that.

[J96 0]

I am a tool.

[Kid Dynamite 5890]

[J96 0]

And I rate Steven Taylor

[Jusoda Kid 1]

And I rate Steven Taylor

 

 

Who the fucks that?

[Guest Stevie]

This will be a must have accessory on Merseyside.

[Sima 0]

Mods, any chance of getting J69 one of these cloaks, his username makes my eyes bleed.

 

I'd much rather his keyboard just had one tbh.

[JonGoodwyn 1]

And I rate Steven Taylor

:icon_lol:

[Guest Stevie]

I am a tool.

Fuckin hell you had a moment of clarity?

[Guest Stevie]

Ah 96, never mind. Justice for the 96.

[Kid Dynamite 5890]

And I rate Steven Taylor

:icon_lol:

 

Who the fuck are you!!!