Chinese physicists create illusory, “ghost” invisibility cloak

Autore: ExtremeTech

Chinese ghost cloaking illusion device

Chinese physicists have created an illusory, ghosting invisibility cloak — a cloak that changes the appearance of an object so that it looks like something else. In theory, you could cover a soldier with this cloak and make it look like something else — a cactus perhaps, or a dog.

In general, ghost cloaks — which are a type of illusion cloak — have two functions. First they must hide the subject, like an invisibility cloak, and then they must somehow project the image of another object. If you read ExtremeTech, you’ll already know that we’ve made some great strides towards devices that provide some semblance of invisibility — but we’re still a long way from creating the metamaterials required to provide true, three-dimensional, panchromatic invisibility cloaks. Instead, the Chinese physicists decided to skip the invisibility bit, and jump straight to the second step: creating a cloak that projects the image of another object.

Tie Jun Cui and his colleagues at Southeast University in Nanjing, China have created a cloak that scatters incoming light to create two “ghost” images either side of the cloaked object. Depending on the construction of the cloaking device, the shape and other properties of the ghost images can be altered. The cloak itself is fashioned out of thousands of split-ring resonators (pictured above) — a structure commonly used in metamaterials that affects electromagnetic waves in weird and wonderful ways.

Ghosting cloak diagram thing

The end result is that the cloaked object is still visible, but significantly shrunk and distorted. Once you factor in the two ghosts, the overall picture is very different and much more complex than the original. If we imagine a real-world example, this cloak could turn an aircraft — which has a very recognizable radar signal — into a small, indeterminate object, flanked by a couple of birds. Whether the cloaked object is distorted enough for this approach to be effective remains to be seen, though.

Still, it’s easy to see how a ghosting device could be used in concert with other techniques to evade detection — if not from radar and other advanced sensing technologies, then at least from human eyes. It’s also exciting to imagine the possibilities of an illusion cloak, when we finally crack true invisibility. Instead of simply vanishing — which is admittedly rather neat — you could become something or someone else.

Now read: Canadian camouflage company claims to have created perfect invisibility cloak, US military soon to be invisible

Research paper: DOI:arXiv:1301.3710 – “Creation of Ghost Illusions Using Metamaterials in Wave Dynamics”

Chinese physicists create illusory, “ghost” invisibility cloak ultima modifica: 2013-01-22T15:34:51+00:00 da admin

4 thoughts to “Chinese physicists create illusory, “ghost” invisibility cloak”

  1. The WRITTEN text (of Chinese) that is used in mainland China and among people of Chinese origin in Singapore nowadays. This written form mainly evolved and was adopted after the end of civil war and the establishment of today’s P.R.China in 1949, so you may also call it as a relatively “modern form” of Chinese text. The reason and purpose for the Chinese government to develop this simplified writing system is believed to be “simplifying the writing method, easing the effort in writing, and encouraging more people to become literate.”

    Il testo scritto (cinese) che viene utilizzato oggi in Cina e tra le persone di origine cinese a Singapore .
    Questa forma scritta principalmente evoluta è stata adottata dopo la fine della guerra civile e la fondazione di PRChina odierna nel 1949.
    quindi si puo definirlo come una retaliva forma moderna del testo cinese.
    Si crede che Il motivo e lo scopo per cui il governo cinese ha sviluppato questo metodo di scrittura semplificata/ sia la semplificazione del metodo della stessa, attraverso la diminuzione della difficolta e incoraggiando piu persone all-istruzione letteraria.

  2. mi trasformate queste frasi in negativa e interrogativa??? x lunedììì e sono
    1 we live in a small town
    2 they are spanish tourists
    3 rob has got a new mobile
    4 i studi chinese
    5 my parents play tennis on saturday
    6 my Brothers sends text messages every day grazie in anticipo….
    e in + voglio 5 frasi con un filo logico…prima normali e poi trasformate sempre in negativa e interrogativa!! grazie….

  3. Processore grafico Intel GMA 950 con 64MB di SDRAM DDR2 condivisa con la memoria principale
    La memoria disponibile per Mac OS X può variare in base alle esigenze grafiche. L’utilizzo minimo di memoria grafica è 80MB, per un massimo di 944MB di memoria di sistema disponibile nelle configurazioni con 1GB di RAM.

    è buono questo processore grafico??perchè??spiegatemi dettagliatamente e anche in maniera semplice….
    grazie a tutti

Lascia un commento

Il tuo indirizzo email non sarà pubblicato. I campi obbligatori sono contrassegnati *

Aggiungi una immagine