this is almost unabashedly pornographic. you could at least put a nsfw or a 18+.
--dtd Sat, 21 Aug 2004 10:05:52 -0400
absolutely, how could you openly discuss an I,Cringley article about something as deeply sexual as the GOOG IPO? Have you no shame, have you no decency?
Think of the children, think of the children.
--Evil Bastard Sat, 21 Aug 2004 10:48:50 -0400
You have to be able to distinguish between clutter and doodads. Clutter is a byproduct of life. Doodads are things you bring into your space because they make you warm & fuzzy. It's an incredible bargain to get smiles for 50 cents these days.
--xoxoxo Bruce Sat, 21 Aug 2004 10:54:28 -0400
Heh. Actually, they mostly amuse me because out of the corner of my eye, for a split second they make me think...huh, bananas, food, but isn't it going to spoil all peeled like that?
--Kirk Sat, 21 Aug 2004 10:58:24 -0400
Light can be considered to act like a wave, and so I guess radio waves would act similar to light. Radio waves just have a much larger wavelength compared to that of visible light on the electromagnetic spectrum.
--Candi Sat, 21 Aug 2004 12:34:47 -0400
You're not wrong about radio waves, at least as I see things-- I see the antennas up on towers as torches or spotlights, giving off light of a single color and flickering, I think. And indeed, many things that are certainly opaque to us are transparent or nearly so to radio waves. But they must also have color, since, just as glass is transparent to visible light but not UV, so must a concrete wall be opaque to, say, line-of-sight frequencies (colors) and transparent to others-- so instead of being like glass, it's like colored glass. (Also, if you want, you can fathom the weird glowing light that glows through your head and hand when you talk on the cellphone.)
The other weird thing is scale-- light waves are really tiny and thus can be reflected by and perceived by tiny things, which is why something the size of our eye can make out complex images. To do the same with radio would require, well, a Very Large Array.
--LAN3 Sat, 21 Aug 2004 18:03:04 -0400
LAN3 is right, it's all the same spectrum. It's a bit mentally weird to imagine , but photons can be radio waves as well as light and x-rays. But of course then you get into that whole particle/wave thing. I always imagine a photon as being an element of light, but it could be anything in the electromagnetic spectrum.
--John S. Sat, 21 Aug 2004 23:03:38 -0400
Yeah, actually, I didn't wanna clutter the situation with getting into that whole particle/wave thing quite yet...good old pre-quantum-physics "E+M" is complex enough as it is...
--Kirk Sun, 22 Aug 2004 08:52:45 -0400
actually, my mental model of visible light can be made to include the expanding circle. Reminds me of how sonar and radar displays work.
I had the idea of designing some device that would scan the room with one of those infrared distance-finders and translate it all into a 3d image, kind of like a 3d webcam. But I had this idea before webcams were so cheap.
--Nick B Sun, 22 Aug 2004 13:32:53 -0400
I never knew the ultraviolet spectrum reflected off of glass. Does that mean the light from the sun gets seperated when it goes through glass? I guess that could explain why we get light but not necessarily high incidences of cancer inside. . ..
--Mr. Lex Mon, 23 Aug 2004 06:49:27 -0400
Wave/particle duality is tough to get a handle on. Just be aware that depending on what you are using to detect the energy it may be easier to think in terms of photons or waves.
Anyway, an AM radio station is like a coloured light bulb attached to a dimmer that you wiggle, changing the intensity of the light. FM changes the color of the light but leaves the intensity alone.
Another way to think of it is to consider it in the frequency spectrum. Okay, for AM the bottom of the frequency spectrum (low frequency -> DC) is shifted up to the carrier frequency (e.g. 640KHz). The radio simple performs the same shift in reverse.
FM is tougher, because it takes the base spectrum and flips it on it's side, transforming amplitude into frequency.
Here's an interesting fact - Laserdiscs (the old 12" monsters) encode the video by FM modulating the composite signal with a square wave then stamping it into the plastic platter. So Laserdisc is actually very high quality analog composite video, even though 99% of LD players have S-video outputs. VHS on the other hand stores Chroma separate from Luma which are then combined for output.
--ericball Tue, 31 Aug 2004 16:34:59 -0400