Last Build Date: Fri, 23 Sep 2011 02:38:37 GMT
Fri, 23 Sep 2011 02:38:37 GMTWow. This is sensational news if true. Really, really astonishing stuff with massive implications for Physics and our understanding of the nature of reality.The full paper is on the archive server now.http://arxiv.org/abs/1109.4897v1This blog post interprets the paper.It is a very nice measurement. The experiment, OPERA, measures the centroid of the "Probablity Density Function" of the time of time of flight from the CERN accelerator to the Gran Sasso Laboratory in Italy. (This in itself is pretty amazing since the neutrinos are detected after travelling through 730 km of solid rock!)Of couse there are two fundamental systematic uncertainties one must take into account. The first is the measurement of the difference between the time of neutrino creation at CERN and the time of measurement in Italy. The second is the distance between CERN and the detector.The time difference was obtained by synchronized atomic clocks with greater than 1 ns precision. There is now a massive industry based on precison measurements of distance. This is the world-wide GPS system which allows measurement errors in positions of the order of centimeters. Its extremely hard to see how they could have screwed these up. For example the April 7th, 2009 L’Aquila Earthquake in Italy resulted is an easily identified 7 cm shift in position. (See below.)The biggest uncertainty is establishing the original time structure of the proton beam that created the neutrinos. The proton pulse is of the order of 10 microseconds in width. The measured effect is a 60 nano-seconds shift from expectations with a 7 nanosecond uncertainty. That means they've established the centroid of their proton pulse width to a precision of better than one part in one thousand. Since they have recorded 16,000 events they have sufficient statistics to do this. The question is whether they've correctly determined the shape in time of the original proton beam.This is determined from the proton beam intensity which is continuously montored. They compared the this to the measured time profile in their detector. The measured original proton beam intensities as a function of time are shown below. The CERN SPS has two extraction profiles which are easily distinguished.The observed time structures of the events recored in Italy are shown below. The red lines show the superimposed average time structures of the proton beams with and without the flight time to Italy.By eye the original time structure of the CERN proton beam appears well reproduced in the detected neutrinos.After a full blind-analysis they find that their neutrinos travelled (60.7 ± 6.9 (stat.) ± 7.4 (sys.)) ns faster than light over the same distance.The first uncertainty is the statistical precision of the measurement. The second is their estimate of the systematic uncertainty. Their systematic uncertainty was obtained by a quadratic sum of 12 potentional sources of error. The largest (5.0 ns) was the calibration of the detector that measures the time of the proton beam extraction at CERN.Overall their measurement gives:(v-c)/c = (2.48 ± 0.28 (stat.) ± 0.30 (sys.)) ×10-5This is consistent with an earlier but less precise measurement from an experiment in America with the Fermilab accelerator:(v-c)/c = 5.1 ± 2.9×10-5But substantially different from the neutrinos detected from Supernova 1987a which gives a limit on the anti-neutrino velocity difference of:|v-c|/c < 2×10-9So what happens now? There are two other high statistics long-baseline experiments in operation in Japan (at the KEK laboratory where I do my CP-violation experiments) and an updated experiment using the Fermilab accelerator in America. You can be certain that both experiments will do their best make the most precise measurements of the neutrino velocities they can. If all three agree what then? Well we will have to wait to see if they do.... As I said this is a most incredible result.One final point about this. If the neutrinos from SN1987A had had the increa[...]
Wed, 15 Jun 2011 01:24:59 GMTHi everyone,
Tue, 29 Mar 2011 12:55:59 GMTIt's been a long time since my last post, but it is worth noting that for the 6th year in a row, AbiWord is back as a Google Summer of Code project in 2011. If you're interested in participating in the development of worlds coolest Word processor, check out our project ideas and get in touch with us!
Tue, 10 Aug 2010 10:49:01 GMTI have a large presentation on my work computer. My colleague wants me to send it to him. I'm at home. I could copy it to my home PC then attach it to an email. The problem is that my home machine has a nice fast (1 megabyte/sec) download connection to work but only about 60 kilobits upload. Sending it from home will be slow...
Wed, 31 Mar 2010 22:55:26 GMTI came across this remarkable article and photograph in todays online edition of the TheAustralian.
Sun, 21 Mar 2010 07:07:10 GMT
Fri, 08 Jan 2010 06:39:26 GMTI'm off to the beach (Apollo Bay) next week and decided I needed to remain connected to the net. After checking around I found that Telstra is the only carrier that has coverage down there. Further checks implied that their USB broadband modems worked under Linux. After checking out the option I bought Telstra's casual plan and their "Telstra Turbo" USB mobile. This has the advantage of being able to be discontinued between uses. The price per GB is about 5 times greater than other Australian carriers. On the other hand, Telstra really do have a very wide coverage and this really is expensive. The other carriers are essentially limited to just metropolitan areas.
Sat, 26 Dec 2009 10:37:21 GMTThis post is public domain. Feel free to copy and paste where ever you like The combination of the AbiWord word processor and the http://abicollab.net webservice provides world-leading real-time collaborative functionality available nowhere else for any price at all. Now that Fedora 12 is out and distributes AbiWord-2.8 it is easy for Linux users to try it out and see if they find it useful. My previous blog posts about http://abicollab.net focused on the use of the service from within a browser. You can find them here: 1. Basic operations including how the AbiWord “save” function sends the document back to abicollab.net.2. How one could go about finding the friend you want to collaborate with.3. How to setup a real time collaboration4. The use of Groups, View, Export in abicollab.net AbiWord also has additional hooks back into the webservice that are accessible from within the “collaborate” menu. To start with we need to establish the connection with the service. This is done with the “account” menu item.I’ve already got an account set up based on my gmail email address. However if I didn’t or if I wanted another based on a different email address, I just click “add” and fill the details as shown. Besides the web service one can connect to other AbiWord using either TCP/IP (if you know the IP address) or via the jabber XMPP protocol. The webservice is much easier for users and connect with. Everyone on the internet has an email address. Clicking the button on “connect on application startup” means you don;t have to go through this step again. If I now go back to the “collaborate” menu and choose “open shared document”, AbiWord connects to the webservice and presents me with a list of the documents I have to on http://abicollab.net Here are the list of groups and user accounts which contain documents I’m allowed to edit. The 3 Martin Sevior’s show up because I have 3 separate accounts on the service :-) Of course clicking the table expander arrow shows me all the eligible documents. As you can see I use the service and find it a convenient way to keep my work in synch across my 3 different work environments. (Work workstation, laptop and home PC). Finally one can upload your current document to the web service. This is a very convenient way to both share your work with your colleagues and to upload it to the service and make it accessible to a different workspace. To this click on “share document” in the collaborate menu. You have the option of sharing the document with as many of your groups and friends on the service as you wish. Once uploaded to http://abicollab.net the document is of course available to be shared with your friends and colleagues and easily available at all your work spaces. Like my previous posts this document has been uploaded to abicollab.net and is available at: https://abicollab.net/documents/embed/17606/latest [...]
Mon, 02 Nov 2009 05:46:45 GMTGroups, View, Export in abicollab.net This post is public domain. Feel free to copy and paste where ever you like The first 3 articles of this series showed some basic operations of abicollab.net, how one could go about finding the friend you want to collaborate with and then how to setup a real time collaboration. In this post I will talk about the Groups, View and Export features of abicollab.net. Groups One often has a collection of colleagues, friends and co-workers with similar interests who need to work together on documents. The abicollab.net webservice makes it easy to allow collections of people to form a group and to work together on common documents. For testing purposes I've created a number of abicollab.net identities for myself and I'll use these to show how one creates such a group.Simply click on the "my groups" link. You see the list of groups for which you have membership.To view the documents held by the group or the membership click on “view documents” or “view members”. The screen shot below shows the membership of the “abicollab” group. We’re the group that directly codes and tests the abicollab.net webservice. Marc and I are administrators of the group. Either of us can approve whether an applicant can join the “abicollab” group. Applicants to the group are shown in the “Aspiring members list”.To create a new group, click on the “create a group” link, type in the name you wish and click “save group”.The new group is created with you as the administrator.Here I’ve created a group called “MartinSeviors”. Now suppose another user called “M. Edmund Sevior” wants to join this group. He navigates to “my groups”, searches for the group by typing in it's name, then clicks “Join a group”.Now the administrator of the group receives an email of this request which also shows up as a message in his “message central” region.I can now accept or decline the request. After accepting the request, navigating to “my groups” and clicking the member list shows the updated member list.Any group administrator can promote any other member to become an administrator too.viewThe “view” link associated with every document shows the contents of your document in your browser. What you see is what you would get if you exported the document to html. With this one one can quickly tell if you have selected the right document to edit, without having to download it into AbiWord.exportEvery document on abicollab.net can be exported into a number of common word processing formats. This is accomplished via the “export” link. One chooses the preferred format then clicks “export". This post is available on abicollab.net at the link:https://abicollab.net/documents/embed/10651/latest.[...]
Sat, 31 Oct 2009 08:49:36 GMTReal time collaborationThis post is public domain. Feel free to copy and paste where ever you like.My first two posts showed some basic operations of abicollab.net and how one could go about finding the friend you want to collaborate with. Now I'll talk about the killer feature: Real Time Collaboration!To set up a document for Real Time Collaboration, one simply sets the permissions to "view & collaborate" for the friend with whom you want to work with the "share" link associated with the document.Then choose who you want from your list of friends.Click on "save settings" and the permissions are set!The document now appears in the list of documents available for your friend. Since you've allowed your friend to collaborate on the document, it shows up on the list of documents he can work on. The friends "my documents" view is shown below.Now you open the document by just clicking on its name and it opens in your AbiWord. Remember you need version 2.8 or later. You start typing away....(Your version of AbiWord shown below)OK, now your friend logs in and sees a new document, shared with him. He decides to edit it too and so opens it. It loads into his version of abiword.Hey presto we have a Real Time Collaboration!So both of you can type away in the document, editing as you wish while you see each others changes in real time. If either press "save" in their AbiWord, the current version gets saved into the history of the document on the website.I just want to point out a couple of things. Your friend did not actually download the document from the website. It had never even been saved! Instead what has happened is that the two have established a peer-to-peer collaboration via a abicollab.net router daemon. The website joined a connection from you to a connection to your friend and passed traffic between the two of you. After that the two AbiWord's transferred the document and established the collaboration.Consequently everyone is guaranteed to always see the absolute latest version of the document! We've totally eliminated the edit=>email to colleague=> update/comment/fix => email =>update/comment/fix => email... cycle.There are many other very cool things about AbiWord's real time collaboration but I'll save them for other posts.You can find this post on abicollab.net at:https://abicollab.net/documents/embed/9886/latest[...]
Fri, 30 Oct 2009 02:03:40 GMTThis post is Public Domain. Feel free to copy and paste as you wish.
Thu, 29 Oct 2009 04:47:33 GMTThis post is public domain. Feel free to copy and paste where ever you like.Firstly, we made slashdot!Secondly reading and answering the comments made me realize how hard it is to explain all the cool features of http://abicollab.net. My intention is to post a series of blog posts to try to fix that. http://abicollab.net is designed to make it as easy as possible share work and collaborate in document production with friends and colleagues, no matter where they are in the world. The service uses very little resources so it quite feasible to host a medium sized organisation, say a 1000-person business or High School, from a single server.The main strength of http://abicollab.net is also its biggest drawback. You need AbiWord-2.8 or later. If you don't have that you miss out on the best features. Getting AbiWord-2.8 for windows is trivial. Getting it for Linux is harder at the moment but will become easier with time as it gets bundled with distros. It is even harder for OSX because you'd have to compile it as an X11 app.Having obtained AbiWord-2.8, lets go through a work flow. This is not the only work-flow and I'll post about others later. This example shows how to use the storage features of the web service. I personally have 4 separate work environments. My Linux partiton on my laptop, my windows partition on my laptop, my work workstation and my home PC. Just using the central storage facilities of abicollab.net saves me a whole lot of hassle.First we log into the website and it takes us to the "my documents" page.Next we decide to create a new document and host it on the site. You do that by clicking on "new document" and filling out some info about the document.We see the document has been created.Now we'll tag it so it can be easily sorted. We click on "tag" in the range of options for the document.Ok now we actually want to put content into it. So click on "open" or the document name.http://abicollab.net downloads a router file with the MIME extension ".abicollab" to firefox. Firefox has registered this as being associated with AbiWord, so it loads AbiWord which grabs the router file and uses it to extract the document from the web service. The result is that AbiWord opens with the contents of the document hosted on the web service. In this case the document has just been created so it is blank.OK now we edit away in AbiWord until we think we'd better save it. To do this we simply click on "save" in AbiWord and the document is saved back to the web service.The complete history of the document is recorded on the web service. To view it, simply click "history" next to the document.This history of this document contains just the initial creation, which is of course blank, the second from this save. One can immediately inspect a particular history by clicking "view".OK so now we edit away in AbiWord as we wish, saving whenever we want. Each save gets recorded as a separate history.Now I'll set the permissions for the document. Permissions are "none, view,view + collaborate" for "everyone, friends, groups".For this document I want everybody to be able to view this document and people in the abicollab group to be able to collaborate on it. We set permissions by clicking on "share".Finally for today you can post the document on the web in variety of formats with the "Link" command.I'll create a link to a HTML-sized version of the document that opens in firefox. I do this by choosing "embedded link"And here is the document on the webhttps://abicollab.net/documents/embed/7851/latestEvery time I click "save" in AbiWord the contents of that link update to reflect the latest version.The next post will cover sharing and collaborating with colleagues.[...]
Tue, 27 Oct 2009 21:09:54 GMTThanks to awesome work from a whole collection of people in the AbiWord team, the great folks at BetterBe.com and creative genius types at lemon8.nl, AbiWord-2.8 is released together with a totally revamped http://abicollab.net. This website tightly integrates with AbiWord-2.8 and enables easy real-time document editing, stores documents online, allows easy document sharing with your friends, and performs format conversions on the fly.
Wed, 21 Oct 2009 11:01:56 GMTBest fan production ever!
Wed, 23 Sep 2009 23:34:37 GMTDear Lazyweb,
Mon, 24 Aug 2009 00:37:34 GMTFollowing on from James Denton's project last year which got us MultiPage View (available in our upcoming 2.8 release) I had the good fortune to mentor Aditya Manthramurthy this year. Together with legendary AbiWord Hacker Joaquin Cuenca Abela, we fixed two of the four issues that slow down AbiWord's performance for large documents.
Thu, 28 May 2009 12:19:24 GMTAlthough Australia is a First World country, to our shame, many indigenous Australians, particularly those in remote communities, have far fewer choices and live a marginalized existence.
Thu, 30 Apr 2009 14:27:20 GMTI was happily chatting away with my great friend uwog (Marc Maurer) on #abiword this morning, when my 15 year-old daughter looked over my shoulder and asked:
Thu, 19 Mar 2009 00:00:14 GMTWe're back and looking for students to mentor in AbiWord hacking for Google Summer of Code in 2009. Thanks Google! We really appreciate your support.
Mon, 09 Feb 2009 04:59:45 GMTFebruary 7th, 2009 was the day I turned 50. It was also the hottest day ever recorded in Melbourne, reaching 46.4 degrees, a good 0.8 degrees hotter than the previous record set way back in 1939. I was planning to writing a long blog post about this but it feels so wrong.
Thu, 11 Sep 2008 01:37:20 GMTLast night my time, the Large Hadron Collider at CERN successfully circulated beam in both directions. We also recorded beam-gas interactions in the ATLAS detector. So all in all it was great start to a grand experiment which has been under development for 20 years.
Wed, 13 Aug 2008 03:19:06 GMTEvolution has a number of great features that make it the best way to interface to our stupid MS Exchange server at work. However it does tend to hang on average once or twice a day while moving email back and forth to the Exchange IMAP service. At this point I find I need to find and kill all the separate processes used by evolution and restart. This got tedious enough that I wrote a stupid python script to do the work.
Tue, 29 Jul 2008 05:31:16 GMTDue to an overwhelming response from our users we've