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Old Apr 8th 2019, 08:59 AM   #1
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How can we become invisible.

As per my understanding what we see is nothing but light reflected through an object. So if an invisibility gadget be invented it shd allow light to pass through the man.

So in order to do so the gadget has to change the atomic number and atomic mass to that of a substance like glass or so.

Well my question is that what is difference in objects is it atomic mass and atomic number due to which they appear different?
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Old Apr 8th 2019, 09:15 AM   #2
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To get light to pass through a man you would have to change the structure of the material making up his body to such an extent that it would be impossible for him to survive.

It is easier to cause the light to bend around the man such that it appears on the other side exactly as it would if he were not there.

This has been demonstrated with small objects and micro-waves,
but to get it to work with light (simultaneously at all visible frequencies)
is not currently possible.
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Old Apr 9th 2019, 12:18 AM   #3
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New problem.

Originally Posted by Woody View Post

It is easier to cause the light to bend around the man such that it appears on the other side exactly as it would if he were not there.
But then when light bends around him I think he would be visible as a dark object since there is light everywhere else and all other things are visible. Isn't it?
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Old Apr 9th 2019, 04:22 AM   #4
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The trick is to bend it around, and then back again
so the light, after bending around goes back straight as it would have been if it had not gone around.

Very careful measurement would be able to detect the time delay, because the light has traveled further,
but that would be a very tiny difference.
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Old Apr 9th 2019, 04:32 PM   #5
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the cloth of invisibility ...



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Old Apr 9th 2019, 05:45 PM   #6
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Ambrose Bierce wrote a short story titled "The Damned Thing" in which people were attacked by an invisible beast. It ends saying "There is a color we cannot see! The damned thing is of that color!"

Of course, there is a color we cannot see! It is called "black"!
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Old Apr 9th 2019, 07:18 PM   #7
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Cool lizard

Woody's first post is right. You make him glass man you make him die. A lizard can survive in this thread.
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Old Apr 10th 2019, 02:34 AM   #8
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When I posted my initial reply about curving microwaves I was thinking about an esoteric negative refractive index material I had read about in new-scientist.

However on further thought, what is the principle mechanism behind the majority of disappearing magicians?
"Smoke and Mirrors"

Suitably aligned mirrors reflect the background around the magician (or assistant, elephant, etc...) so that the object seems to disappear.

(The smoke is just to redirect your attention momentarily so you don't notice the re-alignment of the mirrors).
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Old Apr 21st 2019, 09:07 PM   #9
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Did anything more come out of this research? https://www.techtimes.com/articles/8...nt-wear-it.htm?

I haven't read anything else. It's interesting to see how man has wanted this for thousands of years, and yet it has not been one of the easier problems to crack.

Last edited by zoey; Apr 21st 2019 at 09:09 PM. Reason: I wanted to add more.
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Old Apr 21st 2019, 10:04 PM   #10
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Talking

Die hard VS probability of survival.
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