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First off, this question may seem highly stupid at first, but it arose from past cartoon memories. In the cartoon Tom & Jerry from the 1940s, there was already hypothesizing over cream that, when applied, makes you invisible.

I have looked into invisibility, and I see that nothing surprising has been done. For example, only success in certain magnitudes, presets, lights, etc., but not enough for this to be any breakthrough yet. So my question is:

Is an invisibility cloak that can make a completely visible object in visible light (me, for example) completely invisible (after I put it over me, my torso/body appears to magically vanish) to someone whilst wearing it possible, with just a cloak itself and nothing else?

Truly invisible means:

1.It can't be camouflaged; you must literally appear invisible with no distortion, traces, or signaling that someone or something is/was there.

2.It must be only accomplished by a cloak itself, and no add-ons or special presets must be met; no light tricks, external items needed, etc.

How about "vanishing cream"? Is It somewhat possible?

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    $\begingroup$ First question: Are you only worried about invisibility in the visible light spectrum? Or also invisibility in infrared, xray, radio, etc? Second question: What should appear in your place? The image of whatever is behind you is probably what you have in mind, but "nothing (black, no emission)" is another possible answer, and more easily achieved. $\endgroup$
    – Kyle Oman
    Mar 4, 2014 at 21:44
  • $\begingroup$ There are people actively working on it, but I don't believe that there's anything portable like a cloak yet (or in the near future). $\endgroup$
    – Kyle Kanos
    Mar 4, 2014 at 21:55

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A qualified Yes - Theoretically Possible - and new developments need presenting at this time as referenced below.

  1. One method - In theory if we can bend the 100% incoming light around the object the object would be invisible. MetaMaterials with negative refractive index can do this.

  2. Second method - If we can scattered the light sufficiently that too should will render the object invisible. Fano Resonances is one way to accomplish this.

http://www.nature.com/articles/srep08774

There are a number of other methods under devbelopment :

"Several approaches for achieving the cloaking regime have been proposed on the basis of metamaterials, and they employ transformation optics, cancellation of light scattering, nonlinear response of multi-shell structures, as well as the use of multilayered plasmonic particle, graphene, and magneto-optical effect with an external magnetic field."

  1. Bending light methods with negative refractive index using metamaterials

Source : https://occupycorporatism.com/scientists-perfect-nano-tech-develop-invisibility-cloak/

UCF - University Central Florida NanoTech Group has created Metamaterials that can be printed on a 3D printer that a very reasonable size. Debashis Chanda at the University of Central Florida (UCF) has created a way to bend light with artificial nanostructures to develop an invisibility cloak. Chanda and other nanotech experts have developed a large swath of a “multilayer 3-D metamaterial” that operates “in the visible spectral range”. This was accomplished by “using nanotransfer printing, which can potentially be engineered to modify surrounding refractive index needed for controlling propagation of light.” Chanda explains: “Such large-area fabrication of metamaterials following a simple printing technique will enable realization of novel devices based on engineered optical responses at the nanoscale.”

http://www.nanoscience.ucf.edu/chanda/images/news/BeforeItsNews.pdf

"The nanotransfer printing technique creates metal/dielectric composite films, which are stackedtogether in a 3-D architecture with nanoscale patterns for operation in the visible spectral range. Control of electromagnetic resonances over the 3-D space by structural manipulation allows precise control over propagation of light."

Interesting Source already mentioned : { but not the latest } http://science.howstuffworks.com/invisibility-cloak4.htm

I mentioned I qualified my yes above because I considered this question more deeply over lunch and I see a flaw that needs to be addressed. Although we maybe able to bend light around the an object and perhaps scattered it sufficiently via Fano Resonances I think that we will also need to adjust for the background's light moving to the observer. Looking at this more closely suppose a tree is in the background of the object. We would probably need to take the light that is coming off the tree behind the object and in someway change its path and move it around the invisible object so that the observer sees the tree. Any help on this point is appreciated.

In closing I would have to conclude we are not quite there yet but we have made some well worth mentioning progress.

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  • $\begingroup$ Neither of these meet the OP criteria of "no distortion". An "invisible" object that scattered or bent light would look different than nothing at all. $\endgroup$
    – Dave
    Oct 28, 2015 at 19:31
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    $\begingroup$ I have qualified my answer. Taking the light from the background would look as though there was no distortion. How of course has yet to be determined. Sorry about that I had to run to lunch before completing and refinning an answer. But once I started scouting the topic I thought it was worthwhile to present what I found to forum. $\endgroup$
    – StarDrop9
    Oct 28, 2015 at 19:38
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    $\begingroup$ Even a perfect metamaterial invisibility cloak can't quite meet the OP's requirement of no signalling that something was there, because light will take a longer time to go around an object than it would to go straight through thin air. $\endgroup$
    – bdsl
    May 14, 2017 at 15:16
  • $\begingroup$ One could imagine using advanced A.I. software {with machine learning}, fast CPU's and flash memory that digitally captures the background image in real time and the "computer" cloak then broadcasts the background image rather than a distortion of the light of the real object. One would envision the computation would take place faster than the rate of the human eye. Perhaps this does not meet the OPs criteria but it sure is interesting of thinking about it in this perspective. Providing the observer a digitally prepared representation of the background image instead of the object's light. $\endgroup$
    – StarDrop9
    May 15, 2017 at 18:09

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