Technology related projects

Techdemo, 2012. 3D printing, 2012 Graph project, 2011 Structure from Motion, 2009,2007 Geodesics, 2009,2008 Flash PITF, 2004 Sofia AI project 2003/2004 CCP 2001 I,II

Technology notes 2016, 2007-2010, 2011-2015, 2016, Now

28-12-2016: Advertisement works. After seeing Casey Neistat flying and using a Gear 360 camera, I needed to try it out. Especially, after having done work in Summer 2007 and 2009 with Jose Ramirez on 360 degree camera structure from motion mathematics. The camera arrived today. Its nice, small and handy. Easy to use. Not like the 360 degree camera picturs and movies done since 2006. My first 360 degree movie was done on March 7, 2006, more than 10 years ago, and I had to write the unwrapping software by hand in C. Now its very easy. Just push a button. Unfortunately, Samsung really sucks when it is about compatibility: as they want to sell their phones, no other platform is supported. The movies produced by the camera can not be opened in Quicktime. The stitching software only works on Windows (no Parallels support yet). Anyway, here is a test.
14-12-2016: An amazing NYT article about AI in translation. Intelligent tasks are now faster replaced by bots than manual work. In a lecture on AI, for a Math 1A course, where some of the lectures were taped for a HILT project the question was whether calculus teachers and professors in general will be replaced by bots. Its a rhetorical question of course because all MOOCS and online lecture efforts are part of that trend (they are pushed by universities in particular to reduce the teaching staff in the long term). There is no question that this will going to happen also education more and more, not only in law, medicine or finance, where AI already plays an important role. There is a silver lining: we have seen that the cyborgs were not coming on mass (Google glass did not crash because of technology but because google glass wearers became Glassholes) and robots might have a hard time too (Google sold Boston dynamics not because the technology has no future but because of the PR disaster of the company seen as a job killer (especially this movie). In the case of software, it might be realized only much later, when software engineers are no more needed. The argument "we will then just do the more interesting stuff" does not work any more if the machines already start to do exciting work. And understanding text in context and translating it well is already challenging. Soon, the neural nets will start to program and test and develop independently. The fun will stop when the time comes and software companies like Google will no more hire humans any more, because the machines do it better. Kurzweil made a splash a decade ago by predicting this to happen in the near future. Its funny how we predicted hardware advancement much too optimistically (flying cars, humans on mars etc). In software AI, the flying cars already do exist.
11-12-2016: PDF compression used to be quite well done by Acrobat Pro. As this app is now no more available as such (only per subscription, a app delivery model I by principle avoid, as a user needs to be in control to update or refuse an update), one needs to look for alternative. I have tried a couple of squeezing apps, or online compression tools but they are disappointing. What happens often is that after some editing of the PDF (trivial things like removing a page), the preview app on OS X has blown up the PDE considerably by a factor 2 or 3, sometimes even 10). I currently deal with a 60 Meg PDF (a 500 page book) which had been nicely OCR'd, but has after an edit with "Preview" grown to 180 Megs. "Acrobat Pro" (my old stand alone version) as well as cheaper apps like "PDF Squeeze" did not reduce at all. "NX Power lite" was the best so far and could reduce it to 120 Meg. I can not bring it down to the original 60 Meg although.
Here is my ultimate dream app (which does not exist yet and will probably not do so for a while): The application reads the PDF, extracts text and formula, pictures and rewrites a LaTeX document with embedded pictures. Now, it compares a raster screen shot of the newly generated PDF with the old one, adapts the TeX code until a match is complete on a raster level. This might need to replace some text (like unintelligible parts) with pictures until one has reached a "fixed point".
The format DjVu already does a remarkable job in splitting a document up more intelligently. I doubt it will replace PDF. One reason now is that smart phones and tablets can not read them without special apps. And in general, anything which needs special applications should be avoided. This for many reasons, one being that apps also often report, what you are reading, for how long, when etc. or worse, that they suddenly stop working when the developer disappears or pull the plug. I personally say "no" to "news apps", "video apps", "reading apps", or "streaming apps" as the user loses control in each case (for example to store the content for later view).
31-10-2016: No escape key for the mac book pro. Well, I could not afford it anyway but this is a deal breaker. I do all my work with the "vi" editor. The caps lock key could have gone without problems, but not "esc". Yes, one could reprogram it to an other key, but I need first to see whether this works for me as I hit the escape key probably 1000 times every day.
Update of November 22: after remapping the escape key to caps lock (the most terrible key), I think I can actually could get used to an eternal remap. By the way, I had for 10 years used exclusively the Happy hacking keyboards and still have some of them lying around. One of the best features had been the lack of the caps lock as well as the lack of windows key. It could however happen from time to time that a weird key combination would trigger the caps lock, which required to know the magic key combination to reverse it.
Update of December 5: Remapping the escape key to "caps lock" did not work well after all. One reason is that one of the most often used keys is which I use for command completion. For some reason, I mixed up tab and command too much, especially when working intensively. Its like when playing piano, much reflexes are "in the fingers" and "not in the brain". This is good so, because when writing, one does not want to spend CPU time on thinking where to type but focus on the actual writing. Thats for me the reason, why I universally use one editor for everything. Writing in a web interface is sometimes necessary but annoying: on "canvas" when writing emails, the lag can be so big like when writing on a 56 K Modems in the old times. When writing on a Wordpress page, one gets also reminded how horrible editors can be. Even little things like "new line" wrapping which online editors take seriously disallow to write structured text.
28-10-2016: Two announcements which came about at the same time:
When looking at the page views, Microsoft clearly wins. The Microsoft studio looks nice. In innovation, MS is ahead in this announcement. But les see how the devices actually sell. I myself can not imagine bending awkwardly over the computer screen, when working, always looking for that shiny silver wheel, lifting the screen up each time, I want to write something. It is kind of a brutal realization that innovation alone does not always pay off. The tools have to work. Well and reliably and safely. And guaranteed to be supported for some time. And as a general rule in technology the pundits are most of the time completely wrong, they often simply have no clue. (And this blog entry is included in the assessment.) Too innovative creations can turn off customers because they feel that the idea might be abandoned, if not successful, leaving them stranded. About innovation for the Macbook Pro: already leaving away standard USB ports in the new Mac Pros is daring and led to a lot of critics even so, with guarantee, the old USB ports will in a few years be legacy and a sign of `dusty old stuff' like floppy drives, SCSII interfaces, CD ROM. And soon, the spinning hard drives will be gone too. (One could be wrong here and spinning platters could be with us for 10 more years too). The Galaxy 7 disaster has shown that sloppy innovation or optimization can cost billions. The copy cats are fast. The Iphone innovation (june 2007 announcement) helped apple, but already months after the introduction of the iphone, in 2008, android was there (alpha versions were there already before the iphone announcement, making clear that already in the developent phase of the new operating system for the phone, the copy machine has been turned on). What kept apple alive was the solidness of the operating system, I actually don't recall any phone crash ever. It is simply mind blowing how fast innovative ideas are copy-pasted in our time, sometimes even before the original idea has been realized by the innovator. Lets see which of the two devices (Studio or Macbook Pro) will sell better. There are very smart people in both companies. Apple sees that these years, the PC currently loses out towards the laptop as more and more work is done on the go, in coffee shops, at home, at the beaches, in the mountains, and no more in the office and content is kept on servers. The Mac Pro had therefore priority over the Desktop Pro, which is in a limbo. The studio could become a hit, but it also could just remain a niche product (from a practical point of view, the bendable screen needs quite a bit of real estate, how stable is that screen actually is and how many times one can lift it up until the stand breaks or whether one can push on it hard as one does when working on paper; how is the silver wheel powered (batteries?), how many cables were not shown?). The studio is more like a competition to the iPad Pro or a Wacom tablet, which both are more portable and work similar as a paper surface to draw and do not need cables, can be carried around on the sofa or taken outside etc). I can imagine in future to have a foldable and lighter Ipad which comes with a pencil allowing wireless charging, to replace paper and pencil eventually. Still, with my Ipad Pro and super cool/expensive 100 dollar pencil, I still stick often to paper and pen. I would love to have some cash available to get the new macbook pro. Especially the Terabyte harddrive (final cut or presentations and electronic books and media use a lot of harddrive space) and the fast processor and more RAM would be a blessing when using mathematica. For now, I love the Mac book. As for my main work PCs (who do more and more work for me all day), I stick with high quality, reliable and quite Iron in the form of thinkmate workstations. Old fashioned PCs have their use too: they are at a fixed location and so in a stable environment, more safe, more reliable. They work uninterrupted all day and night and are customizable. Apropos the later, my dream configuration would be a 40 TB harddrive, 1 TB RAM, 22 core Intel Xeon monster for 20'000 dollars. I myself have only a 2000 dollar versions both at home and the office, but they are great and together produce a reliable two location backup, (with long term backups even at an even other undisclosed location, not the ``cloud" of course). And one can update the screen independently.
26-10-2016: A register article about cloud compares computing with a commodity. Readers there (the register reader community is pretty strong), pointed out quickly some fallacies of the analogy of comparing computing with food, gas or electricity: the vendor lock-in is rather strong and in if things go like with ISPs, there will be much more consolidation and lock-in leading to price hikes in the future, once everybody has become a junkie. The global risks are enormous if core business functions of many companies are in the hands of a few. A melt-down of a major cloud provider today already would not only cripple businesses or universities. Because it happens at the same time, it could also trigger a global catastrophy. [Update March 2, 2017: register: AWS failure. Many students at harvard had been affected during exam times as their course websites were not available any more. I keep the course website on a unix server, which was not affected. The story illustrates again that it makes sense to diversify and decentralize IT and allow for redundancy (I can switch over to an other server within a minute as the published page is a mirror itself).
21-10-2016: Since the webcamera is windows only, and under wine or crossover, the configuration did not work, I had to get installed Windows 10 under Parallels. To get there, some hurdles needed to be passed, to be finally get it (one can not use a harvard email address for example to register at Microsoft when buying a home edition). Then, from an old registration, there were first confirmations and reactivation processes necessary. The installation under Parallels went pretty smooth however. Not longer than a Linux or OS X installation. Microsoft has made much progress there. The Windows edge browser however was a NO-GO for the webcam. Under Internet explorer, the Trendnet plugin started to work and I could finally close those damn IR lights. (I had first over glued them with black tape with the effect that also the light sensor got mixed up, rendering the camera blind). Here is "first light" at night without the LED:
12-10-2016: I had run a webcamera for 10 years from 2000 to 2010 from my old office Science center 434 (which is now part of the common room). I just got a new one (trendnet). It is cheap, comes with a terrible "windows only compatible" interface (and a cam which has a reputation to be hackable) but fortunately, it can FTP to my office machine. The cam is not on the web and only accessible from the internal network behind the firewall. The picture gets pushed regularly to the webserver: click on the picture to get the latest picture. here is the Plaza webcam which streams and the Science Center Webcam
[Update evening: having the IR lights behind the window is not a good idea. I will have to turn them off but I can not without running Windows.]
10-10-2016: Last Thursday night, one hard drive on an office machine started to corrupt files (only a handful were affected). Obviously I had waited too long with prophylactic hard drive replacements. Indeed, that one was 3 years in place. I have several backup drives (mirrored, on different machines) so that it was no problem to switch over Friday morning but I work now on one of the "green" backup drives, which is slower. Still, it was annoying to see individual files starting to become unreadable, one does not know at first, how far the rotten sector goes and needs to check, whether some backups have been affected too and also restart scientific computations which were running in the background. For such runs (which are alive over months or even years) it is really helpful to write data continuously onto the hard drive and having the programs work in such a way that one can restart them even in a failure or power outrage (like last Sunday, when the science center power went out (announced for a few hours). Fortunately, rsync chokes, when encountering a funny file. In such incidents, its always good to have a few hours left for checks, especially as one does not want to lose work done during the switch-over time. Having completely independent backups on other machines and long term backups helps. Still, I think to go back to a rigorous replacement of hard drives, even if they are healthy. For a moment this weekend, I had been tempted to get one of those 4 TByte SSD drives just to try out. But the prize (now still over 1000 dollars) is too high. I have all my linux operating system drives on SSDs since 2010 but it would be nice to see what difference it makes for the main drives. On an older iMac, I had once replaced the main drive with a 1T SSD and it had put new life into that 7 year old mac. How long until the 4TB SSD drives become cheaper than the spinning platter versions? I guess it will happen within the next 5 years. [October 29: just saw that Harddrives are now awailable in 10 TB size].
01-10-2016: A rehearsed version of my talk given in Philadelphia:
30-09-2016: Some things seen at a 3D printing session: John Zweck has some nice models illustrating continuity. In 21a, we just covered on Monday with the case f(x,y) = x2 y/(x4+y2), the textbook example of a case where the radial limits are all zero but the limit along some parabola is not zero. The picture to the right was rendered with the code of John, just used different color. A nice blog also by Elizabeth Denne.
25-09-2016: A new technology venture:
21-09-2016: Installed Sierra OS X, 10.12 on the mac. Not a smooth upgrade. Trashed my terminal settings (a small issue). More serious is that Mathematica 11 now crashes regularly when using 3D graphics. Even after a fresh reinstall of Mathematica. Bummer. [Update 9-22. Wolfram confirms the issue. Update: 10-2. The new version 11.0.1 of Mathematica works now well.] An other change: like also the newest Ubuntu distributions, SSH is now upgraded so that it does not connect any more to older ssh servers. Needs an entry
    HostKeyAlgorithms +ssh-dss 
below the line
 Host *  
in /etc/ssh/ssh_config . This of course makes SSH connections less secure but is the only way to connect to older servers until they are updated.
18-09-2016: New google earth experiment.
The program Sketchup now does not feature 3DS any more (just fails to import on Sketchup Pro) But DXF of Autodek worked. The Penrose triangle was imported as a DXF file. With the basic sketchup, the 3DS is the format to choose as DXF is not supported. What a mess with 3D file formats. Having something which works universally for mathematica, 3D printing, Google earth and basic tools like Meshlab seems impossible. Shapeways for example accepts X3D for color prints. Mathematica can not manipulate (even import) kmz files generated by Sketchup.
03-09-2016: Had some strange routing problems with my office machine with intermittent loss of DNS info. It was the router (I keep both at home and in the office an additional router between the web and the machines), which means at home that there are two routers as the router provided by the ISP must be considered compromised (the ISP has administrative access to it). After replacing the router with a new one, things worked again nicely. Afterwards also upgraded from Ubuntu 14.04 to Ubuntu 16.04 as once one is aggravated, it does not matter to become a bit more. The upgrade went very smooth. As it was unexpected (in the past, this always broke some things with my non-standard setup), I'm grateful.
02-08-2016: This summer, there were a couple of email messsages which just did not get into the mailboxes. From canvas seems that the unconventional canvas format (no sender address, the use third party server etc makes the filters nervous). Also some classical emails from students did not arrive at my destination. In one case, we could trace it to an email plug-in which track whether the email has arrived. If you should use such an add-on, better turn it off, as your email might get labeled as spam (the involvement of third party servers is a sign of a test whether the email works). Such games anyway do not work for many email clients as more and more, the default is to ignore contacting third party servers which is how it should be.
15-07-2016: Here is an other google earth test. Recorded on a macbook.
This reminds me: in 2007, I had been a faculty advisor for a Harvard group called "3D Harvard" led by Jason Gao. The goal had been to digitize Harvard for Google earth. I myself helped with the Widner library (particularly simple). The group did make quite a bit of progress: an example: Thayer. I still have my photos, made of Wider library hoped to be used for a nice 3D model. The steam went a bit out of the group, once we realized that Google was must faster and more accurate with automatically building the 3D objects from maps. This might also have been one of the reasons, why google sold Sketchup: the machines are just much more efficient than the community in building up the world! The following video from 2016 shows the progress done. I myself have constructed the science center in Povray in 2001 (shortly after arriving at Harvard. It took me weeks to build that): The source files are here and to the right is the output: 10 years ago, Google started the 3D buildup of buildings. Here is a capture from 2005 without flight simulator, when google earth was not yet on linux so that it ran on a virtual machine under vmware. Now we almost have a computer game. I made the following video on a tiny macbook and not on a stronger desktop on a wireless internet connection in starbucks. But it gives an idea about the progress: Link frameborder="0" allowfullscreen>
10-07-2016: My 7 year old imac (running for 7 years day and night) finally died. Obviously heat (we don't have air conditioning and that particular 27 inch model had always had a bit of cooling problems). I'm forced now to do video editing on the laptop. Just did some editing of a 1minute movie on my laptop. Finalcut grabbed 100 Gig (some optical flow analysis). Always working at the edge of HD capactity is annoying. Can not wait until Macbooks come with 1T harddrives. 16 Years ago, when we moved to Arlington, I had still 1Gig external harddrives When we came over in 1993, I still had all my files backed up on floppies. That one minute final cut project would now fit on 100000 floppies.
10-07-2016: Updates on Cellular automata. Here are some cool ones: Walled Cities, Gnarl, LSD or Maze.
21-06-2016: WebGL is great. Here is a visualiation of quaternion primes. I had kept a demo file NaCLb5 demo template (the author is unknown), which was used as a basis. While looking for modern guides for 3D visualizations in WebGL, almost all you can find are huge library based examples. I like selfcontained, small things which guaranteed will work in 20 years as everything, even the UI parts are in. There are large frameworks like Threejs. Unfortunately, the IOS support is still bad. One can see the WebGL but not interact. Some really cool things have been done in WebGl. A nice example, is this Physics plugin< for threejs.
14-06-2016: Big victory for net-neutrality. New File system coming to apple. Its time this crazy case insensitivity in HFS+ goes away. Its still not recommended to format the boot drive as a sensitive system. I constantly have identified files by syncing to my laptop. Fortunately sync not really merge them.
13-06-2016: Our old Jane Austin DVD collection (BBC series) was seen so often that the DVDs got scratched. Especially since they are double sided DVDs. I bought them twice. Now, they start failing again and I wanted to rip with Handbreak. Does not work any more. Also an old backup version now fails. I bought now Pavtube Byte copy for the mac, which works nicely and produces nice .mkv files with subtitle options. I like the Matroska Multimedia container format more and more. Its an open standard, the VLC player presents it nicely and like DVD's restarts where seen the last time. The converter also allows to make 1-1 disk copies so that one can play the local copy with DVD player.
13-06-2016: MS buys Linkedin: an other worrisome power-grab, which I'm not at all happy about. Its clear that since the phone business and game business have both crashed, the company needs to expand in other area. So far, I had liked linkein, but I might have to delete that account soon. I had liked Skype too, until MS took it over. The problem with these services is that they need to make money eventually. At the beginning, it is honeymoon and free, until a critical mass of users have signed up, then a big buyer slurps it up, squeezes as much money out of it as possible, means spam, adds, ``premium services" having your data sold etc, then discards it. Its still too early to judge, but I have no doubt that MS will have no scruple to sell the company again if it will not make money. That buyer will then sell it to the whoever can squeeze out even more from the user data. Its the circle of life.
10-06-2016: A USB C - Lightening cable, I had got from a third party (FlashTech) used to work well with my 12 inch laptop. Since the last IOS update of my iphone, it gets locked out. There is a complain: "This cable or accessory is not certified and may not work reliably with this iphone". No option to proceed on your own risk, the iphone now just refuses to use the cable. The cable is ok. I can use it very well with an old ipad, which I have refused to upgrade due to hardware limitations. While I understand that companies need to protect their hardware, this is way over the top. While googling, I'm surprised to learn that others have had this before like 2014. I got the cable in late 2015 and it has worked before. Maybe, the database of certified cables has changed recently. Maybe also that the cable has a history of problems. [ Update June 13: actually, it might even have been that my own problem with the USB plug had its origin with that cable. See the earlier story. It might be that cases like mine has led to a purge of non-authorized cables. Well, USB C is still too fresh it seems. ]
01-06-2016: A just uploaded video is also a test on technology in producing high res 4K animations. A youtube version from more than a year ago. Vimeo is better in allowing downloads in 4K resolution.
12-05-2016: . The Harvard Summer school also moved to a search only catalog. Today, I wanted to look for my course with search but there was no match. 5 other courses show up. How Bizarre! Not that we need more students in that course, but I can imagine that for other courses, such non-sensical search results matter. The solution would just be so easy: just dump a list of all the courses in one single document (361 courses times 200 Bytes is about 50 KBytes). Its still 20 times less Bytes than the Java script (about 1 MBytes) which is just used to serve the database results. When the college moved to a search only catalog last year, they asked a few incoming freshmen to search for courses and gave prizes away for finding them. It is funny to see the future elite given prizes for such a task but its in the same time maddening. When I mentioned this search problem at a town hall meeting, a solution promised was an API for search. But APIs have the same problem: they are impossible to audit. And APIs are very frustrating because they evolve or disappear leaving users stranded. Thats why the entire "semantic web" idea which was hyped 15 years ago, failed and simple "information dumps" have succeeded. Yes, they are technologically boring but they work.
04-05-2016: Just after restoring the OS on a repaired ibook, quicktime 7 lost some abilities (despite the fact that I had made a 1-1 copy). Quicktime 7 was a great product. but seems not be maintained well and also needs to be purchased (even from a backup, one has to reenter the registration code). Apple should add back basic export and editing abilities to the standard quicktime application (we need only export and copy-paste features as in quicktime 7, nothing fancy. The trimming feature is not enough. Quicktime 7 is nice, as it does not require for any little piece to fire up "final cut", which for small tasks already fills up hard drive space and after every use, requires to be purged in order to regain space and avoid to see traces of old projects.
As I need to process hundreds of Mathematica submissions, I also need to automatically batch translate .nb mathematica notebooks to .m texfiles. Mathematica notebooks can be suckers. Yes, also the .nb file format is a textfile but with insane markup making the content almost unreadable for humans or dynamic content. Mathematica sometimes has problems with quitting processes. It used to be Java processes which had to be killed by the script processing things, now there are NBImport processes locking up and preventing Mathematica to restart (without any warning, just plays dead). Here is a script killm which needs to be invoked by other scripts to "clean out the pipe". Its also handy to kill Mathematica (which likes sometimes to "compute" and lock the user out even preventing to quit the program). Unlike other operating systems, Unix is great that the user has the last word, when working on the operating system level. On OSX one has lost some of the abilities, but in Linux, the user still has full control. Of course, developers of programs like firefox, mathematica, gimp, rythmbox want their programs not to quit so they cling on, even if the users want to quit them or if they are stuck and even the good old Ctl+C or Ctl+D are disabled out by the developers. Thats when scripts like "killm" are handy. In scripts, processing automatically what human work with graphical user interfaces would need days to do, such "nuclear blasts" are handy. Dodge this!
28-04-2016: More and more companies seem to use email tracking techniques. I currently process 300 mathematica project submissions and got some emails using a "mixmax" Plugins, where the attachment is not displayed but tracked and delivered on request. The idea is that the user can see whether the attachment is opened. Does not work with me, as I use the good old "mail" program to read email (a very convenient way is also to read directly the inbox "vi /var/mail/knill" as the simplest way to find anything is to open it in an editor or use good old unix tools (for example to process hundreds of submissions, unpack them and excecute them). There was a time, when marketing folks used hidden pixels in the email to track emails until the email clients stopped loading images by default. I think the time will come when email clients allow to suppress any unwanted espionage [04-30-15: just saw that OSX Mail (which I only very rarely use) has this option already. One can prevent the mail client to talk to other servers.] Some operating systems like OS X already by default warn if a program tries to submit information to third parties. An email client should do that too by default. But fortunately there are programs like mutt,mail or pine which work very effectively and don't betray the user and allow also to inspect every single character of the mail rather then believing what the mail client tells.
25-04-2016: Since when does the C compiler gcc require the -lm flag after the command? It used to work for a quarter century with gcc -lm example.c Now we get the error message
 example.c:(.text+0x2f): undefined reference to `cos' 
(gcc version 4.8.4) It breaks virtually any Makefile I have. Now, we need to enter "gcc example.c -lm" in linux. The gcc compiler in OSX does not have this restriction. I don't see any reason why linking options should need to follow a particular order. If any compiler changes have to be done, why not get rid of the anachronistic necessity to have to link basic stuff like math libraries? The compiler should be able to figure it out by itself. But no, instead of simplifying things, now there are operating system dependent (!) requirements about the order in which the flag "-lm" is entered. This is syntax insanity.
24-04-2016: I love the 12 inch macbook. Just like in Murphy's law, exactly 2 weeks past the 1 year warranty deadline, a problem with my USB C port has emerged: the laptop would no more charge. The genius bar technician found today the problem at the Cambridge Side apple store: a tiny bit of debris inside the plug has prevented charging. Unfortunately, this debris also produced some power shorting and damage. I had to send it in to repair. What was nice with the mag-safe adapter of the older mac airs and other laptops is that the plug is completely accessible and robust. Even if something should mess up the plug (like some iron dust sucked up by the strong magnets), it could be removed easily with a brush. With the new USB C port, the technician had to look with an endoscope inside the plug to find the problem. Mechanical failures are still the number one problem for laptops: I have had failed CD ROM drives or faulty keys or faulty hard drives. Fortunately the CD roms are gone and the moving platter hard drives disappeared. And broken keys can be repaired easily by ordering replacement keys. A broken charging plug however dooms the machine. I have had one of the first Apple powerbooks which apple produced and there the power plug also had been the main problem. Maybe the time will come when laptops can be charged wirelessly. This will be time when apple will have "No plugs" any more. (There are rumors to get rid of the sound plug in iphones). So, what about solving the USB C issue? I could imagine that somebody develops a small plug just fitting the existing USB C plug which has a magnetic Mag Save adapter. The USB C cable could be refitted too and now, the plug is safe from acquiring small debris and also tripping over the cable becomes again less risky. [ Update April 28: the machine came back from repair. It seems that "repair" is now replacing the entire guts with a new one. Also the harddrive and battery got replaced. It would probably be too expensive to separate the harddrive from the main board.]
22-04-2016: Tried an upgrade one spare office machine (not my main machine) to Ubuntu 16.04 LTS. I wait with my main working machines as usual until things have settled a bit. Glad I did: Here is a screenshot of what happened during the upgrade. The machine became unresponsive no keyboard, nor mouse connection any more. Instead of trying again, I will make a complete fresh install. Upgrades between major OS updates rarely ever worked, even in Ubuntu.
27-03-2016: HP seems to have a super cool clone of the Apple Macbook: here is the add. (review). But there is no wonder companies like HP have trouble: there seems to be no way to buy this thing! It happened before, I remember Dell laptops or cool Mac Pro's which were not available when the customers were made hot for it. There should be a golden rule of advertising: if you make people hungry for a product, give it to them. Subito. We customers often buy spontaneously and after a "wow" experience. Currently, the youtube video points to the "Elite experience", where a thousand and one of other laptops are given. It might not be the case, but it looks and feels like "hardware waporware". Interesting also, that HP advertises their products with Windows 7 Professional as "available through downgrade rights from Windows 10 Pro". This is funny as everybody knows, how hard it is to keep Windows 7 from upgrading itself to windows 10. I myself use windows only for games and have disabled any upgrade communications completely. Windows 10 "big brother features" are unacceptable even as a gaming platform. [Update April 1: HP finally has linked the add to a place where one can buy it.]
24-03-2016: Its now a while, I have done computations on the Harvard Odyssey cluster. (An example was "The battle of eigenvalues"). I need it now for a geometry project since my own machines are not strong enough for some of the linear algebra. Things have improved a lot on Odyssey. I like the Slurm Workload manager which is better than the previous BSUB commands. Also the authentication using the Google authenticator for 2-step verification is easier than what was used some years ago. As displayed on the infographic, there are 207 TB of RAM in total. As a user, I can use 500 Gig.
13-03-2016: More and more programs start to litter the linux home directory with folders like "Documents", "Movies", "Downloads", "Dropbox", "Wuala Drive", "Wolfram Mathematica", "Calibre" etc. It used to be a Windows or OS X thing, but it had started with linux too. I use a very basic windows manager which does itself not do that but some programs do. In the past, programs had used hidden directories or /tmp, but I guess as Linux has become a more main stream alternative to windows, this has changed as many users don't find stuff which are not on the top of their directories. Not that the directory generation problem is unsolvable; one can build new aliases which clean up the mess when the program closes and programs like "nautilus" which mess with the home directory (when evoked without having been asked for by Firefox for example) can be silenced with chmod 000 /usr/bin/nautilus.
11-03-2016: There is an unexpected benefit coming from the fact that word documents can be spiked with vulnerabilities and attack vectors. Administrations are now forced to stop the deplorable practice of distributing information by sending word documents. Word email is not only a waste of space when sending attachments to thousands of people but also a nuisance for email readers which refuse to open attachments blindly, as one has to go through some checking whether the source is indeed what it appears to be from. Word vulnerabilities and exploit kits are still widely distributed. Most recent ransom ware not only encrypts the content of harddrive but also of all backups. I started to keep a more frequent regular physically disconnected backup. Here is a recent ransomware report: one from last month, distributed by word.
17-02-2016: Upgraded Ubunu from 14.04 to 15.10 on my home office. Why ubuntu allows by default guest accounts (where everybody can access the machine) escapes me totally. Placing "allow-guest=false" in /etc/lightdm/lightdm.conf as in 14.04 unfortunately disables lightdm in 15.10 and the windows manager completely fails to start up. As the machine is already online, its no problem to fix this remotely. Some troubles with X (nvidia) got solved by installing gnome (which I myself don't use) but has the effect that it rebuilds some X settings trashed during the upgrade.
22-01-2016: The Wu Characteristic.This was also an experiment in technology, having the text read automatically. About automatic transcript: even so the text is read by computer voices, the language recognition of youtube had some problems when producing captions. The reason was probably because I ased the voices to talk a bit faster than default. Here are some examples
Automated transcript (TXT) Actual transcript (TXT)
Text Transcript
Gauss-Bonnet Gas bonnet
Rene Descartes Rented a car
Riemann Roch Women rock
f-vector Defector
f-vector Effector
i-simplices ice in places with
j-simplices Jason places
entries injuries
one dimensional or dementia
we form the sum we formed a song
book of Klain bucket and clean
Euler curvature Healer curvature
flat there black bear.
even dimensional balls even to mention Obama's
dimensional sphere dimension of fear
the graph S(x) the graphic sex
for cohomology for coca-cola
05-01-2016: A 1500 year old creature comes to life. See data. It is currently in the process of being printed. [Update, the print out came out well].

Oliver Knill, Department of Mathematics, Harvard University, One Oxford Street, Cambridge, MA 02138, USA. SciCenter 432 Tel: (617) 495 5549, Email: Quantum calculus blog, Twitter, Youtube, Vimeo, Linkedin, Scholar Harvard, Academia, Google plus, Google Scholar, ResearchGate, Slashdot, Ello, Webcam, Fall 2018 office hours: TBA Mon-Fri 11:30-12:30 AM and by appointment.