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Math Professor Invents Non-Reversing Mirror

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Re: Math Professor Invents Non-Reversing Mirror

#81

Earlier quoted context omitted.

Have you read fifty shades? I find that people like to bag on stuff they've never actually experienced first hand.

Fifty Shades of Grey is just Jane Eyre rehashed - young virgin falls in love with rich powerful man. Same story, just a little bit more descriptive when it comes to the sex scenes.

The similarity ends on the plot summary level -- which is the most superficial part in literature.

It's also 20 levels below in writing quality, like a messed up straight 20,000 lines amateur PHP monstrosity compared to something written by Rich Hickey.

Re: Math Professor Invents Non-Reversing Mirror

#82
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.

Face mirror. Hold book so you can read it. Now turn it to 'show it to the mirror'. The book is reversed right-left. Because you turned the book right-left.

Try it again - read the book. Now turn it to the mirror, but this time flip it top-bottom. Now the mirror is showing it reversed top-to-bottom, but the letters are still on the correct side (right on right; left on left).

So mirrors Don't reverse left-right. The do whatever you tell them to do.

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