Posts by Jim Logajan

    Yes, well, hmmm.

    Not enough members yet to reach self-sustaining dialogs.

    I'll see about creating some videos that link back here, but it would be a couple weeks at a minimum to get something into the pipeline. I need to figure out subjects that are both interesting and can be reduced to videos with minimum efforts. Ideas welcome.

    I had a small back-room contribution to the DRC Finals that ran this weekend (final results can be found on the DRC website:

    While a lot of progress has been made there still appears to be problems to overcome. The intent of the DARPA competition was to force the teams to build robots that could operate as autonomously as possible. To that end the communications between the robots and human controller was "degarded", which is the portion I was involved in. (I'm always causing people problems! At least now I get paid for it.) The teams had a 9600 bps bidirectional channel to work with at all times and an intermittent 300 Mbps unidirectional (from the robot) channel intended for sending of image data, if needed. Most seemed to need that data stream.

    I think the DARPA challenge results are somewhat relevant to some uses of nanotechnology because the DARPA constraints are roughly analogous to those that nanobots would operate under (e.g. in nanomedicine.) Instead of having to balance themselves, though, the nanobots would have equally challenging problems staying on station, for example.

    If I had to characterize my view of AI and robotics advances in a few words, I'd say capabilities are growing linearly, not exponentially, and there is nothing to indicate to me that advances are being parallelized to make the rate of advance exponential.

    (I got a number of personal photos and videos - mostly redundant or inferior to what you can find elsewhere on the net so I'll only share one of this poor fellow, who took a fall - a common failure mode, it turns out):

    Attached files

    About 12 years ago or so I thought I'd write an article for the proverbial average interested layman that would explore the ways, if any, that nanotechnology could be applied to nuclear fusion. Problem was, I actually didn't know the answer and there was almost nothing formally done other than hand-waving speculation. Besides, there are enormous differences in energy scales between chemical bindings and useful nuclear fusion collision energies (on the rough order of 1000 to 100,000.) So first thing I felt I had to do was write some simulation code to model the nuclei traveling at high energies within some well-known mechanism - such as a proton traveling through an electrostatic focusing lens.

    That was a mistake - at least if I had planned to complete the article in any reasonable time frame. I got a little ways with things, having taken the time-dependent Schrodinger equation (which from a computer programming perspective is really two related equations - one for the real part, one for the imaginary part) and developed a simple program in C and some Python glue code that used the staggered leap-frog algorithm (CTCS) to simulate its time evolution. I found a nice utility to help me generate mpeg movies from a sequence of RBG image files and I managed to put the following initial page together:

    I never got further - realized I was about to embark on an original research project that would take a long time. And the machine I had was no speed demon.

    What annoys me the most, though, is after diligent searching I can't find my old C and Python code anymore. I was sure I had an archive copy of it from the old computer I developed it on, but I've had no luck finding it on the clutch of computers I now have in my office. Of course I could rewrite it, and probably do a better job the second time around, but it annoys me to lose what I considered unfinished work.

    That's interesting since Drexler had this comment on SPM manipulation in "Radical Abundance":

    "Because of the limitations of scanning probe methods (slow, and currently limited to arranging atoms and molecules in two dimensions), I find it difficult to imagine attractive scanning probe– based paths that would lead to advanced AP fabrication. Solution-phase molecular self-assembly, by contrast, already enables three-dimensional AP fabrication on a scale of millions of atoms and in production lots measured in billions. This approach has great appeal. Indeed, from the start, self-assembly is the line of research that I have advocated as a path toward APM-level technologies. The comparatively meager state of the art in nudging molecules with scanning probe microscopes has been a distraction."

    Drexler, K. Eric (2013-05-07). Radical Abundance: How a Revolution in Nanotechnology Will Change Civilization (p. 186). PublicAffairs. Kindle Edition.

    (In my humble opinion "Radical Abundance" is mostly of value to newcomers; those with a historical bent may find Drexler's view of why and how the last few decades unfolded the way the did with respect to nanotech progress may also find it of some interest. Otherwise "Engines of Creation" seems to be the better intro.)

    Based on the wording of the requirements for the Feynman Grand Prize, I assumed that three degrees of freedom (translational motions only) were all that was required - no rotations seem to be mentioned, so 6 degrees of freedom doesn't seem correct. What am I missing?

    Steve, thanks for the thanks. I'm also going to go off-topic to post some miscellaneous thoughts regarding the future of this forum:

    • In order for it to reach a critical mass of active members, as many of the seed group as possible need to get the word out about this forum's existence.
    • My choice of forum software was driven by personal preference and I'm more than willing to change it for something else if the consensus of the seed group sees a need. I selected the BeeHive software primarily because it simultaneously displays thread titles in one frame and the actively read thread in another, thus removing the extra navigation step "up" or "down" between the two displays that most other forum software chooses. But it would be best if such a change in software is done sooner rather than later, so any alternates should be mentioned ASAP. Feel free to suggest commercial software.
    • In the long run I expect the forum to be operated by forum members other than myself. If, as I naturally hope, the forum gains some critical mass I'll be looking for volunteers to handle moderation and admin tasks. Ideally the forum will need to be set up so it survives the proverbial Mack truck running over any one operator.

    I saw that news article earlier this week and at first thought it interesting but made the mistake of watching the 3 minute video they put out. It put me off of looking further into it - looked like hype without being specific. I wanted to see some claim of basic validation like, "We made the following molecules" and then show the chemical structures and/or models for them.

    I really appreciate the links you provided - the "End of Synthesis" was an interesting read - I haven't yet managed to plow through all the followups and fully comprehend all that is being said. I'm also out of touch with nanotech developments in general - I can't tell where things are at. I hope to correct that somewhat.

    So there is not a lot I can add, other than some speculation on the slow progress of DNA origami: technologies like that may provide arbitrary shaped structural building blocks, but what appears to be harder to provide are functional building blocks and a detailed plan to get to the final stage of assembly of the complete product.

    I do need to create some decent documentation on how members can best use the forum software - the creators of the the software I chose seem to have skimped on that aspect. Appears to be a case of getting what I pay for, I guess. I would have used commercial software if I could find any I like - but I've never been a fan of navigating vBulletin forums, which seems the most popular commercial offering.

    By the way, I do find the idea of creating Youtube videos intriguing but the reality is that I always seem a bit pressed for time. After all, it was over two years ago that I first exchanged some emails with a fellow in St. Petersburg Russia who was interested in helping start a web forum substitute for sci.nanotech. It took me that long to finally find the several days I needed to devote to comparing forum software and possible hosting sites, then going through the steps needed to get things running.

    My preference and desire is quality content - not so much lots of traffic. Monetizing this forum is not one of my goals or desires, but I do appreciate the ideas you've put forth in that direction. I suspect it will always be cheaper for me to pay for this site out of my pocket than, for example, fund a flying habit since renting a plane costs $100+/hr.

    But - but - I already have a job that keeps me busy. Thanks to it I'll be one of the people at the DARPA Robotics Challenge in Pomona, CA in June to help mess with the communications between the robots and their human masters (we're not involved in developing any of the robots - we're just there to corrupt communications.)

    Also, it seems to me that a Youtube channel simply moves the problem of generating traffic to a different site - I don't see how it solves the problem. Unless it involves a [molecular] wardrobe malfunction, I'm not sure what would compel anyone to view such videos.

    And I wouldn't know what subjects I could address with any authority - and are both relevant and compelling. Got any nanotech topics you think would make for interesting videos? I think we'd have all of 5 minutes or less to cover a topic, if what I've read about audience retention for online videos is accurate. All I can think of is "Ecophagy - complete wardrobe consumption of Earth's biosphere in less than 2 years."

    Any reason to favor magnetic force over electrostatic force? I ask because pretty much all of organic chemistry depends on things happening because of electrostatic polarities rather than magnetic polarities.

    That said, I don't see why not. I couldn't find any work that seemed to be directly relevant to your question, but a cursory search of the web yielded a lot of interesting stuff using magnetic nano-particles in biological systems.

    When, I wonder, will someone be able to build and operate the arm and adder that are the devices one needs to build per ?

    It is difficult to tell if any progress has been made toward making such devices possible. The only technology I am aware of (I have not done a good job of keeping track of these things the past few years) that I think may be the shortest route is use of wet nanotech and genome engineering to either build tools that then build the devices or that can build the devices directly.