#23420 - 10/31/0211:18 PMRe: deep thoughts and mysteries of the universe.
A flat mirror (as opposed to a parabolic mirror, like a spoon) doesn't change right and left, it reverses in and out. The effect for us is that left becomes right, and vice versa, but that's a perceptual matter. That may sound academic (and it IS), but the difference in the way we perceive the mirror effect is profound.<br><br>To say that a flat mirror reverses left and right sounds arbitrary. If so, then why NOT up and down? Recognizing that the change is not along the left/right axis but along the forward/back axis is the key to no longer being weirded out. Left and right are irrelevant, but what's close and what's further away IS relevant. In spooky theory, if a mirror really DID reverse left and right, then a mirror, in principle, would not be forbidden from revealing distant objects hidden by nearer objects. Now THAT would be weird. <br><br>The axis of reflection is perpendicular to the surface of the mirror (as opposed to parallel to it, which might give you up/down or left/right transforms). The weirdness come from the way you think about left and right. So, you face a mirror. Your right hand appears to be the Mirror You's left hand, right? Now turn around with your back to the mirror. NOW your right hand and the Mirror You's right hand are the same one. What changed? Your relationship to the mirror along the forward/back axis, but even more importantly, your perception of what constitutes "right" also changed. All the mirror is doing is reflecting what is presented to it along the forward/back axis. Walk away from the mirror, you become smaller -- the transform is once again along the forward/back axis.<br><br>Now consider this. You're in your car. You look in the rear view mirror and see my car behind you. I turn my left turn signal on. Which side is the turn signal on in your mirror? Your left side! <br><br>I'm probably not explaining this very well, because it is weird, but a good physics text will probably clear up everything I mucked up.<br><br>
Even simplier<br><br>Since you eye only bends lite once and see like a infinity symbol.<br>Your eye cannot see that infinity symbol twice, = perception.<br><br>Your mind see's in to spheres.<br>Object = image<br>Characture = letters, fonts.<br><br>The - Letters - fonts is reversed.<br>The - object - image is not.<br><br>
Loc: New Hampshire
nice try, but I'm not buying it.<br><br>try this out<br><br>on a piece of paper write -<br><br><br>-------------top---------------<br>left-----------------------right<br>----------bottom--------------<br><br><br>and hold it up in front of a mirror. you'll see it's reversed left to right but not top to bottom<br><br><br>
#23425 - 11/01/0201:48 AMRe: deep thoughts and mysteries of the universe.
The transform remains along the forward/back axis in a flat mirror. Images in a plane mirror appear to be coming from a location behind the mirror that is equal to the distance the object is in front of the mirror. Distance is what counts, not handedness, from the standpoint of physics anyway.<br><br>It looks like this (the mirror image is underlined):<br><br><center>R ----- L<br>|---|---|<br>R ----- L</center><br><br>For the transform to be left/right, it would look like this:<br><br><center>L ----- R<br>----X----<br>R ----- L</center><br><br>To the extent that left/right and top/bottom perceptual constructs exist at all, they exist outside the mirror. Your perceptual construct (as you've described it) is that there is a guy in the mirror waving his right hand when you're outside the mirror waving your left (and no, I don't really think you believe there is a "guy" in the mirror). But it feels like a guy in the mirror is waving his right while you wave your left. But what's really happening is that there is a bunch of light particles following the shortest possible distance between objects, the mirror, and the viewer. To quote my physics textbook (admittedly, all but impenetrable) "Mirrors reflect rays of light symmetrically about the normal to the surface at the point of incidence." There is a straight line between your hand and the surface of the mirror along the shortest path, and then from the mirrors to your eyes, once again along the shortest path.<br><br>A parabolic mirror, in contrast, reflects light particles coming from a different angle than a plane mirror, hence the reversal along the long axis of arc of the parabola (as well as the forward/back transform). A plane mirror has no such axis, and so transforms along the forward/back axis only (or perhaps I should be saying Z-axis, with the X-axis being parallel to the surface of the mirror and the Y-axis also parallel but at a 90-degree angle to the X-axis).<br><br>Ultimately, the problem is perceptual. Which means, we're bilaterally symmetrical creatures oriented perpendicular to the perceived pull of gravity and respond to mirror images most commonly according to this axis. To view a scene from the perspective of the mirror, we rotate along our own vertical axis, either to the left or the right.<br><br>
#23426 - 11/01/0203:37 AMRe: deep thoughts and mysteries of the universe.
Yeah, weird now that you mention it. So what's the explanation for that? Gotta read the posts below I guess.<br><br>errrr.....above now.<br><br><P ID="edit"><FONT SIZE=-1><EM>Edited by mikeb_X on 10/31/02 10:42 PM (server time).</EM></FONT></P>
<blockquote><font size=1>In reply to:</font><hr><p>So top to bottom is always correct but left to right is mirrored.<p><hr></blockquote><p>Our eyes correct parallax view. Otherwise, the sky would be at the bottom in a mirror.<br><br>Makes sense to me. But then, I'm only a kid in my mother's eyes - what do I know?<br><br>
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