(no subject)

[bzarcher]

Ok, here's a fun question for people (that I'm lifting from Forumopolis, I admit):

Does an invisible person cast a shadow?

Discuss.

Comments

[buschap.livejournal.com]

In short, no. Light simply passes through that, like pristinely clear glass.

The real question is, what about sex with an invisible person? Or, less vulgarly, what about things they eat? In their mouth? In their stomach? In their intestines?

[paradisacorbasi.livejournal.com]

There was a Chevy Chase movie that did the "eww, invisible person eating" thing.

[buschap.livejournal.com]

That would probably be Memoirs of an Invisible Man, though I've not seen it.

Predators would probably cast a minor shadow, akin to light through water, or heat radiating off the ground, because their invisibility isn't perfect.

There was a guy that built a house with cameras on one side, and screens on the other. Diagram here, but I originally saw photos in a magazine. This would cast a shadow, and I'd tend to think this would be more how an invisibility cloak would work. Unless a cloak is a marvel of fiber optics and passes light through it.

[degraine.livejournal.com]

You beat me to it. From what I remember, he threw up (which was quite neatly done, like all the 'invisible person interacting with ordinary objects' effects in that movie). And then he woke up later and what was left in him was conveniently invisified. I think we were all relieved about that.

I really need an 'eew' icon.

[twfarlan.livejournal.com]

This depends on the method of invisibility used. If someone is invisible due to becoming physically transparent, then no. No blockage of light means no shadow. However, if the invisibility is due to mental trickery so that possible observers simply do not perceive the person to be there, then yes, the subject still casts a shadow. Whether or not the shadow itself is then seen becomes a factor in the quality of said mental trickery.

[avylin.livejournal.com]

Yes.

However, their shadow, too, is invisible.

[buschap.livejournal.com]

Well-played.

[narel.livejournal.com]

I agree with twarflan (sp?)... I think it would depend on the method used. I expect see-through-ness there would be none, or very little- a dappling on the ground maybe, like a random window in the middle of a room. If it's light-bending, then I would expect there would be a more definite shadow.

[dklegman.livejournal.com]

You really won't care once you realize they have your keys.

[feras.livejournal.com]

no and its for the same reason that an invisible person would be blind.

[neversremedy.livejournal.com]

Depends on the dynamics of the invisibility in question. If he/she is a solid object that refracts light so it appears as if he/she is not there, then a shadow would be cast because light cannot go through them. If he/she is of the invisibility type that also renders him/her incorporeal during invisibility or turns that person into a field of other substance (almost like glass, perhaps?) so that there is true transparency and a shadow would not be cast.