Would not it be wonderful if we could be invisible? Quite right? I mean, we could spy on anyone without being seen and do whatever we want without being held accountable.

The wizards have figured out how to use large mirrors to deflect light in order to create illusions and disappearances.

Scientists have created metamaterials to guide light rays around a tiny two-dimensional objects.
Even cameras can film what c 'behind you and project the image so that invisible appariate front.
However, none of these options can make a big object like an invisible person from all angles and all distances while moving.
But if you are truly invisible, nature, here are some problems that you might not have thought about before.
To move around without being noticed by other people, you should be totally naked.

Although freezing outside! You can not carry anything, including your wallet and keys, otherwise people would see right away the wallet and keys floating around.

Not even the drivers and people on the street could not see you, so that collide with you sooner or later.
Oh, and you had better not put any perfume or breathing so loud, otherwise they will know that you are l.
And, just because you started the invisible day, it does not mean that you will be such.

What would happen if someone accidentally poured hot coffee on him? And what if it rains? But if you think that only liquids can make you visible, you are wrong.

The dust consists of dead skin cells of humans, soil particles, and made of cotton clothing fibers and other materials.

The dust settles with the moisture on our skin when we sweat and the hair when we dry.
So even if you are invisible, however, the dust would settle on any part of your body.
Usually we do not notice the dust on our skin because we can not see a thin layer of powder over skin color.

But, if you were invisible, people would see a dust stain of human form walking with extremely dirty soles.
Raw! How do you think the world is to be invisible? Well, the answer is nothing.
The reason that you can not see in the dark because there would be no light.
To see an apple, light must hit the apple and go back to your eyes.
Then, retinas in the eyes catch the light reflected to the brain that interprets the image of an apple.

If you were invisible, by definition, the light would travel through you or around you instead of bouncing on you by allowing people to see.

But this means that the retinas in your eyes not even catch the light.
As a result, your brain has nothing to interpret as an image.
You can see your reflection without a mirror that stops the light? No.
So when you can not be seen by others, even you can not see.

Ouch! Now, have you ever thought how it would be if it was permanent invisibility? If it were so, how could you receive medical care from a physician if you were injured? The doctor would not know where to apply ointments or bandages because they may not have access to the wound.

For this reason, you might not even see it.

I mean, what would happen if you were sick or you have an infection? How could the doctor make a diagnosis without seeing the color changes or inflammation? What if everyone were invisible permanently? Well, think what the world would be boring without seeing people on the streets, on TV, or at home on the computer, just like now.

sad to be invisible.

Now, what's the next lesson on physical superpowers you explore? Changing the size of the body and content, super speed, flight, super strength, immortality, and invisibility.

From Ted