H. G. Wells' The Invisible Man

[Mentat]

This topic has interested me ever since I read H. G. Wells' The Invisible Man: How can you make someone truly invisible?

Any ideas are welcome, as I have never thought of a scientifically (or even logically) feasible way.

 

[Astrophysics]

Here's an idea...you have a suit with microscobic cells, some of these cells absorb light some are light sources, those which absorb the light give the information (colours, intesity, etc.) to other cells on the other side of this suit. So if you look at a person with this suit on you'll see what you would see if this person wasn't there.
Naturally this is only theory and hardly practicle.

 

[selfAdjoint]

I had an idea like this a few years ago when I was thinking of writing a short story. In the story a peasant has rescued a witch (actually a representative of an advanced society) from the gallows and they have escaped into the nearby woods, but a search for them has been mounted. Now the witch removes her baggy dress which turns out to be just such a device as you mention, but at a slightly cruder level. She whispers to him that it wouldn'y fool anyone in the light of day, but in the woods, at dusk, it just might. They huddle under it deep in a copse of bushes and are overlooked.

 

[Eyesee]

poke the other guys' eye out

 

[Mentat]

Originally posted by Eyesee
poke the other guys' eye out

LOL.

Yes, I thought of this, but I was hoping for something a little less violent .

 

[Mentat]

Originally posted by Astrophysics
Here's an idea...you have a suit with microscobic cells, some of these cells absorb light some are light sources, those which absorb the light give the information (colours, intesity, etc.) to other cells on the other side of this suit. So if you look at a person with this suit on you'll see what you would see if this person wasn't there.
Naturally this is only theory and hardly practicle.

This is what I'm told the new 007 car is like (I haven't - and don't intend to - see(n) the movie). I suppose this is somewhat practical, except that there would have to be a computer that could calculate exactly what the environment would look like (if you weren't there, that is), and change the suit to fit that calculation every time you move. Otherwise, it does seem possible in principle.

 

[Beren]

On a side note:

This is what I'm told the new 007 car is like (I haven't - and don't intend to - see(n) the movie

They actually use cameras that feed what they see to projectors laced throughout the car that projects the image.

Hey, it's a Bond movie.

 

[Mentat]

Originally posted by Beren
On a side note:



They actually use cameras that feed what they see to projectors laced throughout the car that projects the image.

Hey, it's a Bond movie.

I see.

 

[LURCH]

Originally posted by Astrophysics
Here's an idea...you have a suit with microscobic cells, some of these cells absorb light some are light sources, those which absorb the light give the information (colours, intesity, etc.) to other cells on the other side of this suit. So if you look at a person with this suit on you'll see what you would see if this person wasn't there.
Naturally this is only theory and hardly practicle.

This approach has been explored by the US Army. The cells were not microscopic, but small octagons about 3-4 inches across. These were the projection screens, and they fit together like the cells of a honeycomb. At the joints between the screens, there were pinhole cameras with fiberoptic lines running to the appropriate screen the one on the opposite side of the soldier's body).

But, as you say, not practicle. Horrendously expensive to make and almost as bad to maintain, the suit only turns out to be a slight improvement on camo. The plates are large and flat enough to reflect sunlight sometimes, and produce only a fragmented image of the terrain behind the soldier. Maybe the microscopic cells you suggest would work better, but I'm not sure such tech even exists, and if it does, it would be even more expensive.

Maybe in the near future, though.

 

[wuliheron]

The only real practical invisibility camoflage for the forseeable future is for stealth aircraft and ships.

The simpliest way to be invisible is just not to be there. The military already has fly sized video cameras, robotic snakes, and who-knows-what in the works. The next generation of aircraft will theoretically be mostly remote control whether invisible or not.

 

[Eyesee]

An aircraft or ship invisible to the naked eye is worthless.

 

[wuliheron]

What you don't see can hurt you.

 

[Astrophysics]

Originally posted by Mentat
This is what I'm told the new 007 car is like.

Really?...maybe I should go and work for Q then

 

[Astrophysics]

Originally posted by LURCH
This approach has been explored by the US Army.

Hmmm...or maybe I should go and workk for the US Army...

 

[Zero]

There is no possible way to create complete invisibility that is also useful, although you could theoretically get awfully close. The problem is, if you are completely invisible, you cannot see! If you allow light to pass around or through you, no light will reach your eyes. If you absord all light, you will appear black. And if you are simply projecting images for the illusion if invisibility, you will still have a heat signature which can be picked up.

 

[LURCH]

Having given the millitary's approach further consideration, I notice a new possibility. Another project under development for the millitary is the powered armor suit. It would be safe to assume that this suit, when developed, will be as stealthy as DARPA can make it. It will probably have features to decrease its heat and radar signature as much as possible. But the projection method of invisibility would also be made easier by the adbvent of such a combat vehicle. This suit would not require the flexibility of a camo uniform, and so the flat screens with flexible joints between them could be illiminated. The position of each part of the suit's surface is far more predictable, making projection easier and more realistic in appearence.

 

[Mentat]

Originally posted by Zero
There is no possible way to create complete invisibility that is also useful, although you could theoretically get awfully close. The problem is, if you are completely invisible, you cannot see! If you allow light to pass around or through you, no light will reach your eyes. If you absord all light, you will appear black. And if you are simply projecting images for the illusion if invisibility, you will still have a heat signature which can be picked up.

Yes, I'd considered this, and that's why the "invisibility suit" wouldn't necessarily make you invisible, but rather make it so that all others can see is your surroundings. It would also help to have the typical "stealth" features (undetectability by radar and the like).

 

[Nereid]

... simply projecting images for the illusion if invisibility

Here's a challenge: how do you know where to project images to (if it's just this kind of illusory invisibility you are after)?

If you want to appear invisible to observers 'at infinity', a 'light pass-through' arrangement might work; if the observers are close, there's no way you can project images to all possible observers without some parallax problems arising for at least some observers (and if you don' t know where they are, you can't correct for this). Of course, that's not a problem if you're in a blizzard, but then a nice white camo kit would do the trick just as well.

 

[Mentat]

Originally posted by Nereid
Here's a challenge: how do you know where to project images to (if it's just this kind of illusory invisibility you are after)?

If you want to appear invisible to observers 'at infinity', a 'light pass-through' arrangement might work...

Check out Zero's post, he addresses the "light pass-through" possibility.

...if the observers are close, there's no way you can project images to all possible observers without some parallax problems arising for at least some observers (and if you don' t know where they are, you can't correct for this).\

But what if you had a small computer in each "projector", which calculated the distance between you and observers, and thus compensated for differences in PoV?

 

[Nereid]

But what if you had a small computer in each "projector", which calculated the distance between you and observers, and thus compensated for differences in PoV?

The computer would have to know the distance to all objects in the field of view (of the soldier), to even begin to eliminate parallax.

Further, each 'projector' would need to emit through a full ~ 2[pi] steradians, across the whole of the visible spectrum (and into the IR, thank you Zero), with an angular resolution of no more than ~5 arcmin, a response time of <0.1s, and a dynamic range of >5 orders of magnitude.

... and we haven't started to specify the detectors.

Hmm, not your average movie cinema projector; not your average PC.

 

[Mentat]

Originally posted by Nereid
The computer would have to know the distance to all objects in the field of view (of the soldier), to even begin to eliminate parallax.

Further, each 'projector' would need to emit through a full ~ 2&pi steradians, across the whole of the visible spectrum (and into the IR, thank you Zero), with an angular resolution of no more than ~5 arcmin, a response time of <0.1s, and a dynamic range of >5 orders of magnitude.

... and we haven't started to specify the detectors.

Hmm, not your average movie cinema projector; not your average PC.

I concede that you are most likely right. I don't the folks that make 007 movies really cared much, but for practical application this is certainly a barrier.

 

[TENYEARS]

I believe such thing is possible from the person who says they do not believe. It has to do with what gravity is. I also believe it is possible for a human being to become invisible under the correct circumstances. What zero said of light is true from a normal classical situations. There are some situations which are not beyond classical, but which are yet to be defined but do exist. When you understand this you will know it is possible.

 

[Nereid]

Originally posted by TENYEARS
I believe such thing is possible from the person who says they do not believe. It has to do with what gravity is. I also believe it is possible for a human being to become invisible under the correct circumstances. What zero said of light is true from a normal classical situations. There are some situations which are not beyond classical, but which are yet to be defined but do exist. When you understand this you will know it is possible.

Would you be so kind as to elaborate please?

 

[TENYEARS]

Originally posted by Nereid
Would you be so kind as to elaborate please?

I would like to, but now is not the time and maybe there will never be a time. If you want the truth or the answer to a question there is only one way there has always and always will be one way. The paths may look different on the outside, but there is and only will be one way to answer this question or any question. What you should ask yourself is what am I really interested in? This question? The result of the question? Collecting marbles? The human mind is a trickster.

 

[instntpudn]

So I just wanted to let all of you pessimists know that I am in progress of developing the first FULLY spectrum invisible suit. With the new advances in OLED technology the quality, architecture and manufacturability of a REAL invisible suit now seem closer than ever. Inspired by good old Wiley Coyote I plan to have a working CAD model by the end of this year. Questions, comments or constructive or useful critisism or any experience working with OLED email scott_mcq@hotmail.com.

 

[benzun_1999]

Invisibility is suerly possible.........

Look at coal, it is a allotrope of Carbon and it is black and absorbs light but have a look at diamond it is also a allotrope of Carbon but it allows light to pass through. So taking this as an example we can find a way to invisibility.

 

[Mentat]

Originally posted by benzun_1999
Look at coal, it is a allotrope of Carbon and it is black and absorbs light but have a look at diamond it is also a allotrope of Carbon but it allows light to pass through. So taking this as an example we can find a way to invisibility.

But, if we discover a way to let light pass through us, we may become invisible but we will also become blind. See Zero's previous post in this thread.

 

[Rybo]

Dark matter may be more correctly defined as "the missing light"

Fred Holy had suggested that microbes in intterstellar space are --biologic clouds of dust-- abosbing much of the missing light instead of reflecting it or letting it pass through us.

Asorbing the light as a carbon allatope(SP) does not really work. Allowing light to pass though does.

We need to chang our chemistry so that our frequenices do to interfere with the light.

What frequencies of EMRadiation this would be i cannot say for sure other than to guess that any frequcnies other than that of visible light i.e. between the very narrow 450 and 650 nano meters and probablyaway from those nearset to light i.e. heat(infra-red) and ultra-violet.

Then next problem becomes maintaing the integrity of our biologic pattern as EMR in location that is equanimous to where a visible bdoy would be.

Not very likely is my best guess.

Rybo

 

[Nereid]

Originally posted by instntpudn
So I just wanted to let all of you pessimists know that I am in progress of developing the first FULLY spectrum invisible suit. With the new advances in OLED technology the quality, architecture and manufacturability of a REAL invisible suit now seem closer than ever. Inspired by good old Wiley Coyote I plan to have a working CAD model by the end of this year. Questions, comments or constructive or useful critisism or any experience working with OLED email scott_mcq@hotmail.com.

Organic Light Emitting Diode material may be one part of the 'emitter' component of such a suit; what will you be doing for the detector components?

IIRC, OLED materials have some way to go wrt dynamic range and response time before they'd start to be useful. Also, it's hard to see how they could be architected to address the parallax issues.

 

[Nereid]

you can still see a glass object!

Originally posted by benzun_1999
Look at coal, it is a allotrope of Carbon and it is black and absorbs light but have a look at diamond it is also a allotrope of Carbon but it allows light to pass through. So taking this as an example we can find a way to invisibility.

Glass, shrink wrap, and water are, to us humans, transparent. However, if you make an object from either of these, they are still very visible! The visibility of transparent materials arises from the fact that their index of refraction is not the same as that of the air in which we see them. You're not suggesting that we could turn a human into a colourless gas?