How can someone achieve invisibility?

[nazgjunk]

There's also the question of how much horsepower a dude would have to generate to get his mass moving. All of those speedsters in the comics and movies seem to have almost instantaneous acceleration.
There's one statement you made that should be clarified in case someone takes it the wrong way. Both eyes have blind spots, but they don't coincide.

They are comics, please. Ever saw the full DragonBall Z series? It is as unrealistic as hell, but those guys go fast, without aging. OF COURSE it's not realistic.

 

[Danger]

I'm quite aware of that, nazgjunk; therein lies the difference between fantasy and science fiction. What we're trying to do here (even though it got off topic), is find an invisibility device that doesn't violate physical laws. A discussion of various approaches is appropriate.

 

[nomorevishnu]

Kool...I am overwhelmed with the kinda response i have got.But inmy second post I had asked for some technique that would allow a person to intake something and then be invisible.I mean nothing external.Like a drug or injection or anything of those sorts.Immediately my mind can't think of anything in those lines that provides logic...but some vague ideas?I m looking forward to it!
Thanx

 

[Danger]

Okay, Nomore... something just whapped me upside the brain here, but I'm going way outside the box. You never specified if this character has to be human.
If not, what about maybe a silicon-based lifeform that can control its index of refraction?

 

[nomorevishnu]

Oh it is ofcourse human...Thats where the fun always is...
So Mr.Funniest Member...hope something better whaps up...u or me...
Something that can make a human go invisible ok guys?
And it should be internal...not a cloak...Please...i will ofcourse post my idea if something strikes me!

 

[Renge Ishyo]

.But inmy second post I had asked for some technique that would allow a person to intake something and then be invisible.I mean nothing external.

Well, unfortunately humans are made of atoms that interact with light, so without a "work around" or some way to somehow change how atoms behave you are pretty much SOL.

Without the use of some suit or trick to create the illusion of invisibility, I can think of one "real world" way to make a human "invisible" and that is to heat the body until you liquify all the chemical compounds in it and then continue heating it until it enters the gas phase. At this point, it is possible that humans who walked into the room and tried to find this person would not be able to see their body in normal lighting conditions (because it will be in the form of a gas).

There are a couple err...shall we say, "drawbacks" with using this method to become invisible: 1) There is no way for you to control where your molecules are going to go while you are in the vapor state. So you could not mosey your little "cloud" to the front of the line in the DMV or into the girl's locker room, etc. purposefully, rather you would be at the mercy of the wind. 2) You would lose your life in the process as unravelling your molecule structure (while making you "invisible") would simultaneously make you...err, nonexistent (which is not what I think you had in mind).

Now you may be able to think science fiction wise about changing to the vapor state, sneaking past enemy lines or whatever, and then having a computer "reassemble" the molecules exactly as they were when they were done, but if you could go to that sort of trouble you might as well just build the damn suit and be done with it

 

[Danger]

I agree with Renge, Nomore. There is no physical/chemical treatment that can make a human invisible without killing him. If you insist upon making one up, make sure that you refer to your writing as 'fantasy' rather than 'science fiction'. To maintain any credibility, you're stuck with an external device of some sort.

 

[Mixolydian]

One way, I guess.. is just make a suit that obsorbs all light. You wouldn't apear invisible you would be completely black, like a shadow figure I guess it would only work well at night seeing as anyone would only be able to see someone outside in the dark with moon light but the suit would absorb that and you would just continue to look like a dark part of the side of the street or something. Doing it at day time would freak people out.. a random spot of darkness...

 

[langtu]

I still do not understand why a invisible person is blind. Although his or her retain can not reflect light,the light coming to his retain still damages his retain (for example, the light from the sun still burn a plastic or heat from sun still makes the water transfer to cloud although they are almost invisible). Thus, it still causes chemical changes in the photosensitive cells of the retina, the products of which trigger nerve impulses which travel to the brain, so s/he still see as a result.

 

[Mk]

But the cones and rods are invisible, meaning the light goes right through it, unaffecting.

 

[langtu]

I mean the light go throughout one thing does not mean it does not affect on that thing. In fact, the light from the sun heats us everyday although it goes through the air(invisible). Am I right with this example?

 

[vanesch]

I mean the light go throughout one thing does not mean it does not affect on that thing. In fact, the light from the sun heats us everyday although it goes through the air(invisible). Am I right with this example?

Actually, when light goes through something without undergoing any chance what so ever (phase, intensity, direction...), then no, the light cannot affect the thing either.

 

[alfredblase]

One way, I guess.. is just make a suit that obsorbs all light. You wouldn't apear invisible you would be completely black, like a shadow figure I guess it would only work well at night seeing as anyone would only be able to see someone outside in the dark with moon light but the suit would absorb that and you would just continue to look like a dark part of the side of the street or something. Doing it at day time would freak people out.. a random spot of darkness...

Mixolydian, that's the best idea I've read in this thread so far; it would certainly be extremely difficult to spot in the dark, but psychologically speaking, I wonder if the brain would be so freaked out by this moving black thing that it would ignore it even in dayilght

P,S that runequest game sounds like it would make a good computer game, has it been made into one yet?

 

[Gokul43201]

One way, I guess.. is just make a suit that obsorbs all light. ... Doing it at day time would freak people out.

Another reason not to wear this suit in the daytime : Assuming even a minimal solar intensity of 100W/sq.m (that's a cloudy winter day in Maine), and a super heavy suit with a giant heat capacity, it would warm up at a rate of about 6K/min. In less than 20 minutes you can boil water on your suit ! If this is noon-time in Singapore, make that 2 minutes.

 

[damitr]

Even building up an invisibility device, would make person invisible (if possible ) 'only' in some wavelength range.

The device MUST radiate at some wavelength or the other , which will be related to its temperature (BBR).

 

[pinestone]

...Its about making someone invisible.What are the faintest possible ways to do that??Please give me some suggestions.
Thank you!

Eliminate all the light. Nothing is visible in absolute darkness.

 

[-Job-]

Of course that would involve killing oneself.

 

[blimkie]

I love when science fiction novels are somewhat plausible and portray accurate physics, same with movies such as arthur C clarkes 2001: A space oydessy

 

[Chaos' lil bro Order]

NON-SUIT SOLUTION

Most color as we know it arises from the properties of molecules when their Carbon backbone structure has 'conjugated dienes'. This means in lay terms that there are Carbon atoms strung together with alternating single and double bonds (ie. -C=C-C=C-C=C- etc.). The molecule in Rods and Cones that allows us to 'see' light is also a conjugated diene, called 'cis-11-Retinal'. When a photon strikes 'cis-11-Retinal' it makes a conformational change (changes shape) into 'trans-11-Retinal' and essentially opens up a gate through which a tiny electrical current can now pass through and eventually reach the brain, where you perceive this signal as light.

However, 'cis-11-Retinal' is always imbedded in an even larger molecule which is called 'Rhodopsin'. Rhodopsin is a large globular protein (globular basically means spherical) which always has the same basic structure, but there are a variety of Rhodopsin proteins which all vary slightly with the addition of a few atoms here and a few atoms there. Its these small variations that make all the difference to you and I when we perceive the wide variety of colors that we can perceive. For only a specific type of Rhodopsin will allow incident (incoming) light to pass through it and strike the all-important 'cis-11-Retinal' whereupon whenceforth the electrical signal is passed onwards up to the brain.

That is why our 3 color sensing cones, namely the L-cone (Red), M-cone (Green) and S-cone (Blue) are only good at sensing the color of light that their specific 'Rhodopsin' protein let's through.



With all of this background in mind, consider this possible solution for biological invisibility without the need for a suit:

It is possible in theory that you could line your body with Rhodopsin proteins all along the epidermis of your skin and you could then use these proteins to detect all the incoming light around you from all directions (the INPUT part of the problem). Now we come to the more difficult problem of how to get the body to OUTPUT the colors of light we need to perfectly mimic the INPUT signals we have just received.

Generating the proper OUTPUT of colors all over your body surface would require each skin 'pixel' to be a maximum size of say 0.1 mm to ensure that no human eye could be visual acute enough (have good enough vision) to see that you are not invisible, even when their proximity to you is within a foot. Recalling that molecules emit color based on their 'conjugated diene' structure, it is forseeable that we could genetically engineer proteins that produce molecules of all the required colors for our OUTPUT. These proteins could be place locally in the epidermis where they would be interspersed in a mosaic beside our INPUT 'Rhodopsins' and then an INPUT 'Rhodopsin' situated 180 degrees (opposite side of the body) could send an electrical signal through a nervous system (a special nervous system suited to connect INPUTS and OUTPUTS) to tell the OUTPUT protein to generate a molecule that's color mimics the 180 degree INPUT.

This is my idea of how to create biologically induced invisibility. There are several little quarks that I can think of that would need to be smoothed out, for example since the body is not perfectly spherical, the INPUTS and OUTPUTS would not really be perfectly coupled by 180 degrees. Just think of a woman's breast and her back, clearly the INPUT 180 degrees from her breast would not correspond to the correct mimicry of her OUTPUT on her breast, since her breast is curved and her back flat. But I think that you can appreciate that this problem could be worked through by finding the proper INPUT/ OUTPUT mimicry angles needed for all of your body surfaces and its skin pixels.

Other than that, there are a handful of other hurdles to overcome, however I think the guts of my solution is pretty good.

What do you think?

 

[spiffing_abhijit]

A person should stand in front of a mirror and see his image.I would not be surprised that most of u will dislike my idea but it's my suggestion.A man should have and electronically controlled suit which exactly can match 100 per cent accurately with the colour of the existing environment.Also the suit should adjust with the changing light and the changing time and environment.Modern technology has found this invention quite comprehensively and this is not the present issue in front of the scientists working on science fiction.

 

[russ_watters]

That's been done. It requires a camera and a projector, and it really isn't all that useful.

http://www.cnn.com/2003/TECH/02/07/japan.invisible.ap/

 

[banerjeerupak]

well i have a completely different say on this topic. some of you may even like.
as per my knowledge, the vision is possible because something is either giving out light or is reflecting it to some extent.
hence the key to produce an invisibility cloak is to make a material which is completely absortive and does not reflect light to any extent.
obviously, this being an ideal case is not possible but a nearby state may be achieved

 

[Chaos' lil bro Order]

baner

If something absorbs all light it appears black so you wouldn't be invisible but you'd look like a silouette of coal

 

[soul_hunter]

what would happen if one's cells (i mean his or her body), become less denser than the surrounding of him or her? can't her/she go
"_" INVISIBLE "_"

 

[Rade]

Is it possible that the invisible results from a quantum superposition between asymmetrical fundamental particles ? What is "observed" thus depends on how much energy observer puts into the system to break the superposition ?

 

[dav2008]

what would happen if one's cells (i mean his or her body), become less denser than the surrounding of him or her? can't her/she go
"_" INVISIBLE "_"

If your body becomes less dense than air then you're going to have a hard time living.

 

[banerjeerupak]

my mistake

of course i admit that what i said was theoretically wrong.

after me there was a post saying that if we get less dense than air.
that would mean we would float upwards and not get invisible.
but we may argue that if our refractive index is made to be equal to that of air, we would be transparent and so would become invisible.
but the same question crops up that how do we do it.

 

[Farsight]

How about if the guy was shifted slightly forward in time?

 

[thoms2543]

light reflected by the man do not enter your eyes thus become invesible.but how to do?

 

[Danger]

Hmmm... I lost track of this thread for quite a while. Chaos, that's a fascinating approach. Similar in some regards to a chameleon. Definitely worth further investigation.

Just think of a woman's breast and her back, clearly the INPUT 180 degrees from her breast would not correspond to the correct mimicry of her OUTPUT on her breast, since her breast is curved and her back flat.

Well, in the case of my ex-, you've got that backwards.