If light, why not radio?
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From: Jerry Avins on 16 Apr 2010 11:48 http://michigantoday.umich.edu/2010/04/story.php?id=7725 -- "It does me no injury for my neighbor to say there are 20 gods, or no God. It neither picks my pocket nor breaks my leg." Thomas Jefferson to the Virginia House of Delegates in 1776. ���������������������������������������������������������������������
From: Rune Allnor on 16 Apr 2010 12:00 On 16 apr, 17:48, Jerry Avins <j...(a)ieee.org> wrote: > http://michigantoday.umich.edu/2010/04/story.php?id=7725 Of course. Listening to standard radio has made me shiver and cringe for decades already. Hearing an idiotic argument or inferior musical performance makes me phycically ill. Rune
From: Eric Jacobsen on 16 Apr 2010 12:15 On 4/16/2010 8:48 AM, Jerry Avins wrote: > http://michigantoday.umich.edu/2010/04/story.php?id=7725 Hmmm...doesn't say what color light they used. I'd think sorting out any frequency dependence would be useful, so the extension to radio would then be evident. Cool stuff, though. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
From: Clay on 16 Apr 2010 12:53 On Apr 16, 11:48 am, Jerry Avins <j...(a)ieee.org> wrote: > http://michigantoday.umich.edu/2010/04/story.php?id=7725 > -- > "It does me no injury for my neighbor to say there are 20 gods, or no > God. It neither picks my pocket nor breaks my leg." > Thomas Jefferson to the Virginia House of Delegates in 1776. > ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ Hey Jerry, Thanks for the link. I like the way the article acts like light twisting and moving small particles is a new idea. Astronomers have known about light's effect on moving particles (e.g., forcing a comet's tail to point away from the sun.) for a very long time. Also light has angular momentum so light causing twisting effects has been known for a century. Ie. look up the Yarkovsky effect (primarily a differential heating effect). But Beth showed a beam of circularly polarized light imparts a torque when it reflects off of a reflector. I think a problem with using radio's radiation pressure will center around the effective low temperatures associated with radio sources. The forces are just very small. Maybe a 50,000 watt radio source can do some neat stuff, but a simple laser is easier to use. If you are looking to utilize radiation pressure as the primary mechanism. FWIW, Clay
From: Steve Pope on 16 Apr 2010 20:38
Eric Jacobsen <eric.jacobsen(a)ieee.org> wrote: >On 4/16/2010 8:48 AM, Jerry Avins wrote: >> http://michigantoday.umich.edu/2010/04/story.php?id=7725 >Hmmm...doesn't say what color light they used. I'd think sorting out >any frequency dependence would be useful, so the extension to radio >would then be evident. >Cool stuff, though. Light has this cool property that it will change the electronic state of materials. RF doesn't do that. This result, while I agree it's novel, seems akin to lucite becoming opaque in the sunlight... but because they are nanofibers, they deform as the material changes. More of a bulk material is not going to deform. Steve |