[extropy-chat] Center for Responsible Nanotechnology (one year old:-)

[Jose Cordeiro]

Congratulations to Chris and Mike!!!
 

C-R-Newsletter #15    January 13, 2004With this issue, we've decided to start something new: after CRN News,you'll find a brief article explaining a technical aspect of advancednanotechnology. This month, we'll begin with how scientists "see" thingssmaller than a wavelength of light, with cutting edge sub-wavelengthimaging techniques.If you'd rather read this on the web, with nicer formatting and inlinehyperlinks, go to http://CRNano.org/newsletter.htm#15CRN NEWSHappy Birthday to CRN!We founded CRN sometime in December 2002. We can't agree on the date;Chris prefers Mike's original email in early December, but Mike thinkswe should count from the website going online, which happened aroundChristmas. Perhaps the most official date would be when World Care*agreed to support us in being a non-profit. Anyway, those were all inDecember, so we're now one year old.We've done quite a lot in the last year: published numerous papers* andcommentaries, built a prestigious Board of Advisors*, given
 apresentation* to the EPA, been mentioned in US News and World Report,and had articles republished on KurweilAI and in Small Times. This yearwe're going to be even more energetic and diverse.  QUESTION #1: If westarted a nano-blog, would you read it? We'd really like to know. Pleaselet us know. Thanks!The Futurist* published a great article written by Mike on nanofactoriesin its current edition. Small Times* immediately reprinted it. And thisled to a request from another magazine for an article from him, as wellas several newsletter signups.Last month Chris gave his presentation to the EPA Science AdvisoryBoard. It went very well. Everyone on the panel had only a few minutesto speak, and if you've been reading our newsletters (of course youhave!) you know that you can't summarize advanced nanotechnology in sixminutes. But he managed to hit most of the highlights. Several people onthe Science Advisory Board told him afterward that they appreciated thetalk. Chris spent the next day
 talking with several people inWashington, including a Congressional staffer. All the talks werepreliminary, but should lead to good things in the future.There are now almost three hundred people on our newsletter list. That'spretty good! But we'd like to reach more people.  QUESTION #2: Wouldyour friends and co-workers be interested in this newsletter? Why or whynot? Could you take a minute and tell us what would inspire you toforward this newsletter to them?The Drexler/Smalley debate* has not generated an obvious shift ofopinion one way or the other. It looks like we were over-optimisticabout that. Apparently, in many people's perception, Smalley's incorrectstatements about enzymes weren't enough to weaken his argument. AndSmalley and Drexler both talked past each other — which left each sideclaiming victory and ignoring the equally loud victory yells from theother side.In other nano-establishment news, we're eagerly awaiting Howard Lovy'spromised article on the 21st Century Nano
 Act and why molecularmanufacturing was deliberately excluded from it. He's promised that oncethe article comes out, he'll post additional information on his blog*.At CRN, we’re working on our own activist response to this controversy —can’t tell you about it yet, but it’s big, and we should be ready toannounce something soon. Stay tuned!SCIENCE AND TECHNOLOGY — by Chris PhoenixSub-wavelength ImagingLight comes in small chunks called photons, which generally act likewaves. When a drop falls into a pool of water, one or more peakssurrounded by troughs move across the surface. It's easy to describe asingle wave: the curvy shape between one peak and the next. Multiplewaves are just as easy. But what is the meaning of a fractional wave?Chop out a thin slice of a wave and set it moving across the water: itwould almost immediately collapse and turn into something else. For mostpurposes, fractional waves can't exist. So it used to be thought thatmicroscopes and projection systems could not
 focus on a point smallerthan half a wavelength. This was known as the diffraction limit.There are now more than half a dozen ways to beat the so-calleddiffraction limit. This means that we can use light to look at smallerfeatures, and also to build smaller things out of light-sensitivematerials. And this will be a big help in doing advanced nanotechnology.The wavelength of visible light is hundreds of nanometers, and a singleatom is a fraction of one nanometer. The ability to beat the diffractionlimit gets us a lot closer to using an incredibly versatile branch ofphysics—electromagnetic radiation—to access the nanoscale directly.Here are some ways to overcome the diffraction limit:There's a chemical that glows if it's hit with one color of light, butif it's also hit with a second color, it doesn't. Since each color has aslightly different wavelength, focusing two color spots on top of eachother will create a glowing region smaller than either
 spot.http://physicsweb.org/article/news/4/7/7/1There are plastics that harden if hit with two photons at once, but notif hit with a single photon. Since two photons together are much morelikely in the center of a focused spot, it's possible to make plasticshapes with features smaller than the spot.http://physicsweb.org/article/news/5/8/14/1Now this one is really interesting. Remember what we said about afractional wave collapsing and turning into something else? Not tostretch the analogy too far, but if light hits objects smaller than awavelength, a lot of fractional waves are created, which immediatelyturn into "speckles" or "fringes." You can see the speckles if you shinea laser pointer at a nearby painted (not reflecting!) surface. Well, itturns out that a careful analysis of the speckles can tell you what thelight bounced off of—and you don't even need a laser.http://www.nasatech.com/Briefs/Sept00/NPO20687.htmlA company called "Angstrovision" claims to be doing something
 similar,though they use lasers. They say they'll soon have a product that canimage 4x12x12 nanometer features at three frames per second, with largedepth of field, and without sample preparation. And they expect thattheir product will improve rapidly.http://murl.microsoft.com/LectureDetails.asp?1041High energy photons have smaller wavelengths, but are hard to work with.But a process called "parametric downconversion" can split a photon intoseveral "entangled" photons of lower energy. Entanglement is spookyphysics magic that even we don't fully understand, but it seems thatseveral entangled photons of a certain energy can be focused to atighter spot than one photon of that energy.http://physicsweb.org/article/news/4/9/18/1A material's "index of refraction" indicates how much it bends lightgoing through it. A lens has a high index of refraction, while vacuum islowest. But certain composite materials can have a negative index ofrefraction. And it turns out that a slab of such material
 can create aperfect image—not diffraction-limited—of a photon source. This field isadvancing fast: last time we looked, they hadn't yet proposed thatphotonic crystals could display this effect.http://physicsweb.org/article/world/16/5/3/1A single atom or molecule can be a tiny source of light. That's not new.But if you scan that light source very close to a surface, you can watchvery small areas of the surface interact with the "near-field effects."Near-field effects, by the way, are what's going on while speckles orfringes are being created. And scanning near-field optical microscopy(SNOM, sometimes NSOM) can build a light-generated picture of a surfacewith only a few nanometers resolution.http://www.uni-konstanz.de/quantum-optics/nano-optics/singlemol.htmFinally, it turns out that circularly polarized light can be focused alittle bit smaller than other types. (Sorry, we couldn't find the linkfor that one.)Some of these techniques will be more useful than others. As
 researchersdevelop more and more ways to access the nano-scale, it will rapidly geteasier to build and study nanoscale machines.If you have any comments or questions about this brief technicalexplanation, please email Chris Phoenix, CRN's Director of Research.LINKSWorld Care: http://www.worldcare.org/CRN papers: http://crnano.org/papers.htmAdvisors: http://crnano.org/about_us.htm#AdvisorsEPA presentation: http://crnano.org/EPAhandout.htmFuturist: http://www.wfs.org/futcontjf04.htmSmall Times: http://www.smalltimes.com/document_display.cfm?document_id=7161Drexler/Smalley debate: http://crnano.org/Debate.htmHoward's blog: http://nanobot.blogspot.com/Chris's email: cphoenix at CRNano.orgLast month's CRNewsletter:  http://CRNano.org/newsletter.htm#14-------------------------------------------To donate to the Center for Responsible Nanotechnology, go tohttp://crnano.org/support.htm, click on "Donate Now", andremember to specify CRN.  Thanks!The Center for Responsible Nanotechnology(TM)
 (CRN) is an affiliate ofWorld Care(R), an international, non-profit, 501(c)3 organization. Alldonations to CRN are handled through World Care. The opinions expressedby CRN do not necessarily reflect those of World Care.You have received this newsletter because you (or someone pretending tobe you) left your email address at the Center for ResponsibleNanotechnology web site.  If you want to stop receiving these letters,please email cphoenix at CRNano.org and you will immediately be taken offour list.




La vie est belle!

Yosé (www.cordeiro.org) 

Caracas, Venezuela, Americas, TerraNostra


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