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Math Professor Invents Non-Reversing Mirror

techfragments.com

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Re: Math Professor Invents Non-Reversing Mirror

#11

Post by fennecfoxen »

jpdoctor wrote: post #6

> When you look in a normal mirror, the image you see of yourself is in reverse. Funny thing: Mirrors don't reverse left and right. They reverse front and back. So this "non-reversing" mirror is actually mapping y to -y, x to -x (Where the mirror is in front of you in the z-direction. Curious. Edit: I believe tomerv below is correct: x is mapping to -x but y is kept the same.

Demonstration time:

Write something on a piece of paper. Hold the paper up to the mirror.

Now replace that with a transparent piece of plastic.

Re: Math Professor Invents Non-Reversing Mirror

#14

Post by Jun8 »

And he's holding MTW's Gravitation tome in the photo!

BTW: Why do so few people pose with their favorite books (or holding any book) in profile photos, this was common when people had their portrats painted in the past. Has it become a turn-off?

Re: Math Professor Invents Non-Reversing Mirror

#15

Post by adamman »

naner wrote: post #8

I'm having a hard time visualizing this. If I am standing directly in front of this mirror and slowly reach forward with my right hand until I touch the mirror, will my hand be touching its mirrored self?

I'm guessing that the only way you could touch the mirror image of your finger is by doing so in the middle of the mirror. If you move the finger out toward the shoulder, I'm betting your arm would stretch off the mirror away from your body. I could be totally wrong though.

Re: Math Professor Invents Non-Reversing Mirror

#16

Post by andrewcooke »

leeoniya wrote: post #2

was hoping for more technical details. maybe they're still going through the patent application?

according to the wikipedia article it's a surface of micro-mirrors that work in pairs. so it's basically a pair of mirrors scaled down and repeated.

http://en.wikipedia.org/wiki/Non-reversing_mirror

not very exciting really.

Re: Math Professor Invents Non-Reversing Mirror

#20

Post by brianpan »

Jun8 wrote: post #14

And he's holding MTW's Gravitation tome in the photo! BTW: Why do so few people pose with their favorite books (or holding any book) in profile photos, this was common when people had their portrats painted in the past. Has it become a turn-off?

Because it's not quite the same holding a Kindle displaying cover art up to your face.
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