Stephen Sekula steve@hub.polari.us

Dallas, TX, USA

Husband; Associate Professor of Physics; I teach at SMU in Dallas, TX; I study the Higgs Particle with the ATLAS Experiment at the Large Hadron Collider at CERN; writer and blogger; drummer; programmer; teacher; scientist; traveler; runner; gardener; open-source aficionado.

  • JanKusanagi at 2017-12-16T23:24:42Z

    Oh wow, look at that beautiful non-flat Earth!!

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  • JanKusanagi at 2017-12-16T03:29:47Z

    » Stephen Sekula:

    “[...] an you send me the correct site/repo from which to checkout libqoauth2? [...]”

    The repo is github.com/ayoy/qoauth, which I imagine is the one you're using.


    It might help to look at how Debian builds it.

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  • JanKusanagi at 2017-12-13T13:05:23Z

    I once made my own home and surrounding streets as a Doom level. It was fun =)

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  • Explore CERN in the world of Minecraft

    ParticleNews at 2017-12-13T12:28:39Z

    "Explore CERN in the world of Minecraft"

    Students have recreated CERN and the ATLAS laboratory in detail using Minecraft’s signature 3D blocks (Image: ATLAS)

    Now you can discover CERN and the ATLAS detector in incredible detail on the gaming platform Minecraft, through ATLAScraft, launched today.

    The virtual world recreates the Laboratory using Minecraft’s signature 3D blocks, in an interactive museum and map that includes striking images accompanied by detailed explanations and mini-games to explore the world of particle physics.

    The centrepiece of the game is a stunning scale model of the ATLAS experiment, complete with underground service caverns and tunnels for the Large Hadron Collider (LHC). Players can slice open the experiment to reveal layers of subdetectors, watch particles meet at the ATLAS collision point, and play minigames that explain how each subdetector works.

    This virtual world was created by UK secondary school students together with ATLAS physicists, in a project funded by the UK’s Science and Technology Facilities Council (STFC) and the ATLAS Experiment. With the help of experts, the students became the teachers in ATLAScraft, turning their new knowledge of the detector and particle physics into engaging activities for players.

    Explore CERN through the new ATLAScraft game (Video: ATLAScraft)

    https://home.cern/about/updates/2017/12/explore-cern-world-minecraft

    ( Feed URL: http://home.web.cern.ch/about/updates/feed )

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    I once made my own home and surrounding streets as a Doom level. It was fun =)

    JanKusanagi at 2017-12-13T13:05:23Z

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  • Call for Testing: Dianara 1.4.1 Beta

    at 2017-12-09T21:10:03Z

    A couple of days ago I tagged the development version of Dianara, my Pump.io client as beta, preparing for the release of v1.4.1 by the end of the month. As usual, some wider testing would be helpful. If you can build from source, now's a good time to do so and test it. If you already run an often-updated version from git, feedback would be good.


    The main change since v1.4.0 is the ability to save and restore post drafts. CHANGELOG file.


    As announced several months ago, v1.3.7 was the last version to support Qt 4.x. Qt 5 is required since 1.4.0. The bad news is that, at this time, users of distributions such as Debian 9 can't build with the version of QOAuth present in their repositories, based on Qt 4. Current Debian Testing/Sid is fine though.

    Please let me know if you find any issues that are not listed in the BUGS file, or in the issue tracker.

    Also, if you maintain any translations, now is a good time to update them!


    Thanks!

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    Show all 11 replies

    >> JanKusanagi:

    “» JanKusanagi:
    “[...] but there's a undefined-symbol-related error at the end of compilation. [...]”
    Well, no luck. I tried using Debian Sid's libqoauth2 with Sid's qca2-qt5 stuff (which is present in Ubuntu repos) to avoid the linker error at the end of the build process, but that brings other errors due to mismatch in OpenSSL versions.

    I guess the only option for Ubuntu users ATM is building libqoauth2 (with Qt 5) themselves, before building Dianara.”

    I am happy to do that. Can you send me the correct site/repo from which to checkout libqoauth2? I am not confident I have been grabbing it from the correct place.

    Stephen Sekula at 2017-12-16T03:13:41Z

    » Stephen Sekula:

    “[...] an you send me the correct site/repo from which to checkout libqoauth2? [...]”

    The repo is github.com/ayoy/qoauth, which I imagine is the one you're using.


    It might help to look at how Debian builds it.

    JanKusanagi at 2017-12-16T03:29:47Z

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    >> JanKusanagi:

    “» Stephen Sekula:
    “[...] an you send me the correct site/repo from which to checkout libqoauth2? [...]”
    The repo is github.com/ayoy/qoauth, which I imagine is the one you're using.

    It might help to look at how Debian builds it.”

    So, I got QtCrypto and QtOauth to build. But now when I try to build Dianara, I get this:


    ../src/mainwindow.cpp:539:5: warning: identifier ‘nullptr’ is a keyword in C++11 [-Wc++0x-compat]
         logViewer = new LogViewer(nullptr); // under Plasma 5, for instance
         ^
    ../src/mainwindow.cpp: In constructor ‘MainWindow::MainWindow(QWidget*)’:
    ../src/mainwindow.cpp:539:31: error: ‘nullptr’ was not declared in this scope
         logViewer = new LogViewer(nullptr); // under Plasma 5, for instance
                                   ^
    ../src/mainwindow.cpp: In member function ‘void MainWindow::showUserTimeline(QString, QString, QIcon, QString)’:
    ../src/mainwindow.cpp:3207:45: error: ‘nullptr’ was not declared in this scope
                                                 nullptr); // No parent, independent window
                                                 ^
    ../src/mainwindow.cpp: In member function ‘void MainWindow::toggleLockedPanels(bool)’:
    ../src/mainwindow.cpp:3225:43: error: ‘nullptr’ was not declared in this scope
             sideDockWidget->setTitleBarWidget(nullptr);
                                               ^
    Makefile:1220: recipe for target 'mainwindow.o' failed
    make: *** [mainwindow.o] Error 1 

    EDITED:


    I had to edit the Makefile and manually force the use of -std=c++11. That did the trick. Wonder why that wasn't set automatically when creating the Makefile?


    EDITED:


    So now it gets a teeny bit further and this happens:

    g++ -c -std=c++11 -m64 -pipe -O2 -Wall -W -D_REENTRANT -fPIC -DQT_NO_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_DBUS_LIB -DQT_CORE_LIB -I../../dianara-dev -I. -isystem /usr/include/x86_64-linux-gnu5/QtOAuth -isystem /usr/include/x86_64-linux-gnu/qt5/Qca-qt5/QtCrypto -isystem /usr/include/x86_64-linux-gnu/qt5 -isystem /usr/include/x86_64-linux-gnu/qt5/QtWidgets -isystem /usr/include/x86_64-linux-gnu/qt5/QtGui -isystem /usr/include/x86_64-linux-gnu/qt5/QtNetwork -isystem /usr/include/x86_64-linux-gnu/qt5/QtDBus -isystem /usr/include/x86_64-linux-gnu/qt5/QtCore -I. -I/usr/lib/x86_64-linux-gnu/qt5/mkspecs/linux-g++-64 -I/usr/include/QtOAuth/ -o pumpcontroller.o ../src/pumpcontroller.cpp
    ../src/pumpcontroller.cpp: In member function ‘void PumpController::getImage(QString)’:
    ../src/pumpcontroller.cpp:475:31: error: ‘FollowRedirectsAttribute’ is not a member of ‘QNetworkRequest’
         imageRequest.setAttribute(QNetworkRequest::FollowRedirectsAttribute, true);
                                   ^
     I will see if I can track that one down.  The qnetworkrequest.h header on my system (Ubuntu 16.04) comes from this package:

    Package: qtbase5-dev

    State: installed
    Automatically installed: no
    Multi-Arch: same
    Version: 5.5.1+dfsg-16ubuntu7.5

    FINAL UPDATE:

    I edited pumpcontroller.cpp and changed "FollowRedirectsAttrbute" to "RedirectionTargetAttribute", which is a defined attribute in my version of this header. It compiled. Whether that is the correct thing to do, I cannot say...
     
    FINAL FINAL UPDATE:

    OOF. It was not probably the right thing to do. Dianara seg faults upon startup... not sure why, of course, but something went horribly wrong...

    Stephen Sekula at 2017-12-16T18:03:59Z

    Woah, so much info =)


    I don't think you need to manually build "QtCrypto" or Qca-qt5, the versions already available in Ubuntu's repos should be enough... I guess xD



    That network redirection thing requires Qt 5.6, but you could just comment out that line, and you would just be losing the ability to get images inserted in posts whose links redirect somewhere else, so probably not much.


    The std=c++11 thingie used to be manually specified prior to dropping Qt 4 support, but given the compiler and C++ standards requirements of Qt 5, I thought it was no longer necessary. I imagine your version of Ubuntu has a pretty old version of GCC or for some reason doesn't use c++11 or later as a default syntax.



    I'm not sure all this work you're doing to get this to build will be worth it ^^

    JanKusanagi at 2017-12-16T19:42:45Z

  • Christopher Allan Webber at 2017-11-22T05:38:10Z

    BTW, today ActivityPub got voted to go to Proposed Recommendation in the Social Working Group!

    Which means that at this point it's up to W3C membership and management to move it to the space of it being an official spec.

    The implementation reports page is looking pretty good too!

    Now I really need a rest...

    Sean Tilley, Nathan Willis, Blaise Alleyne, Jason Self and 8 others likes this.

    AJ Jordan, Claes Wallin (韋嘉誠) shared this.

    @cwebber@identi.ca congratulations!

    Diane Trout at 2017-11-22T16:44:14Z

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  • Avadiax at 2017-11-18T12:57:54Z

    *DO NOT DISTURB* "The Punisher" binge-watching session is in progress. https://www.netflix.com/title/80117498

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  • Laura Arjona at 2017-11-19T11:08:13Z

    Similar struggle here, I trick myself with decaf, but in any case I try not to drink after lunch, otherwise it affects my sleep pattern.


    The good part is that I (and I guess you) really enjoy that first coffee in the morning...

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  • Astronomy Picture of the Day for 2017-11-04 12:30:02.228099

    Astronomy Picture of the Day (Unofficial) at 2017-11-04T17:30:03Z

    Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

    2017 November 4
    See Explanation.  Clicking on the picture will download
 the highest resolution version available.

    Hubble's Messier 5
    Image Credit: HST, ESA, NASA

    Explanation: "Beautiful Nebula discovered between the Balance [Libra] & the Serpent [Serpens] ..." begins the description of the 5th entry in 18th century astronomer Charles Messier's famous catalog of nebulae and star clusters. Though it appeared to Messier to be fuzzy and round and without stars, Messier 5 (M5) is now known to be a globular star cluster, 100,000 stars or more, bound by gravity and packed into a region around 165 light-years in diameter. It lies some 25,000 light-years away. Roaming the halo of our galaxy, globular star clusters are ancient members of the Milky Way. M5 is one of the oldest globulars, its stars estimated to be nearly 13 billion years old. The beautiful star cluster is a popular target for Earthbound telescopes. Of course, deployed in low Earth orbit on April 25, 1990, the Hubble Space Telescope has also captured its own stunning close-up view that spans about 20 light-years across the central region of M5. Even close to its dense core the cluster's aging red and blue giant stars and rejuvenated blue stragglers stand out in yellow and blue hues in the sharp color image.

    Tomorrow's picture: moon year

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  • Jason Self at 2017-10-25T13:00:10Z

    Maybe they forgot something and had to go back?

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  • Jason Self at 2017-10-25T00:50:25Z

    Santa and his staff are heading north for the winter in preparation for the big production season.

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  • Astronomy Picture of the Day for 2017-10-24 12:30:01.725377

    Astronomy Picture of the Day (Unofficial) at 2017-10-24T17:30:02Z

    Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

    2017 October 24
    See Explanation.  Clicking on the picture will download
 the highest resolution version available.

    Where Your Elements Came From
    Image Credit & License: Wikipedia: Cmglee; Data: Jennifer Johnson (OSU)

    Explanation: The hydrogen in your body, present in every molecule of water, came from the Big Bang. There are no other appreciable sources of hydrogen in the universe. The carbon in your body was made by nuclear fusion in the interior of stars, as was the oxygen. Much of the iron in your body was made during supernovas of stars that occurred long ago and far away. The gold in your jewelry was likely made from neutron stars during collisions that may have been visible as short-duration gamma-ray bursts or gravitational wave events. Elements like phosphorus and copper are present in our bodies in only small amounts but are essential to the functioning of all known life. The featured periodic table is color coded to indicate humanity's best guess as to the nuclear origin of all known elements. The sites of nuclear creation of some elements, such as copper, are not really well known and are continuing topics of observational and computational research.

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    Tomorrow's picture: meteors streaming

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  • SLAC’s Risa Wechsler Named American Physical Society Fellow

    ParticleNews at 2017-10-23T19:29:01Z

    "SLAC’s Risa Wechsler Named American Physical Society Fellow"

    The astrophysicist is recognized for her leadership, mentorship and innovative work in understanding how galaxies form.

    https://www6.slac.stanford.edu/news/2017-10-20-slacs-risa-wechsler-named-american-physical-society-fellow.aspx

    ( Feed URL: https://www6.slac.stanford.edu/taxonomy/term/805/feed )

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  • Astronomy Picture of the Day for 2017-10-22 12:30:02.087132

    Astronomy Picture of the Day (Unofficial) at 2017-10-22T17:30:02Z

    Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

    2017 October 22
    See Explanation.  Clicking on the picture will download
 the highest resolution version available.

    Two Black Holes Dancing in 3C 75
    Image Credit: X-Ray: NASA/CXC/D. Hudson, T. Reiprich et al. (AIfA); Radio: NRAO/VLA/ NRL

    Explanation: What's happening at the center of active galaxy 3C 75? The two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are co-orbiting supermassive black holes powering the giant radio source 3C 75. Surrounded by multimillion degree x-ray emitting gas, and blasting out jets of relativistic particles the supermassive black holes are separated by 25,000 light-years. At the cores of two merging galaxies in the Abell 400 galaxy cluster they are some 300 million light-years away. Astronomers conclude that these two supermassive black holes are bound together by gravity in a binary system in part because the jets' consistent swept back appearance is most likely due to their common motion as they speed through the hot cluster gas at 1200 kilometers per second. Such spectacular cosmic mergers are thought to be common in crowded galaxy cluster environments in the distant universe. In their final stages the mergers are expected to be intense sources of gravitational waves.

    Free Download: The 2018 APOD Calendar
    Tomorrow's picture: rosetta stone galaxy

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  • ATLAS and CMS join forces to tackle top-quark asymmetry

    ParticleNews at 2017-10-20T08:29:28Z

    "ATLAS and CMS join forces to tackle top-quark asymmetry"

    Event display of a tt̄ event candidate in the 2015 data (Image: ATLAS/CERN)

    In their hunt for new particles and phenomena lurking in LHC collisions, the ATLAS and CMS experiments have joined forces to investigate the top quark. As the heaviest of all elementary particles, weighing almost as much as an atom of gold, the top quark is less well understood than its lighter siblings. With the promise of finding new physics hidden amongst the top quark’s antics, ATLAS and CMS have combined their top-quark data for the first time.

    There were already hints that the top quark didn’t play by the rules in data collected at the Tevatron collider at Fermilab in the US (the same laboratory that discovered the particle in 1995). Around a decade ago, researchers found that, when produced in pairs from the Tevatron’s proton-antiproton collisions, top quarks tended to be emitted in the direction of the proton beam, while anti-tops aligned in the direction of the antiproton beam. A small forward-backward asymmetry is predicted by the Standard Model, but the data showed the measured asymmetry to be tantalisingly bigger than expected, potentially showing that new particles or forces are influencing top-quark pair production.

    “As physicists, when we see something like this, we get excited,” says ATLAS researcher Frederic Deliot. If the asymmetry is much larger than predicted, it means “there could be lots of new physics to discover.”

    Standard Model,Higgs boson,Diagrams and Charts
    All matter around us is made of elementary particles called quarks and leptons. Each group consists of six particles, which are related in pairs, or “generations” – the up quark and the down quark form the first, lightest and most stable generation, followed by the charm quark and strange quark, then the top quark and bottom (or beauty) quark, the heaviest and least stable generation. (Image: Daniel Dombinguez/CERN)

    The forward-backward asymmetry measured at the Tevatron cannot be seen at the LHC because the LHC collides protons with protons, not antiprotons. But a related charge asymmetry, which causes top quarks to be produced preferentially in the centre of the LHC’s collisions, can be measured. The Standard Model predicts the effect to be small (around 1%) but, as with the forward-backward asymmetry, it could be made larger by new physics. The ATLAS and CMS experiments both measured the asymmetry by studying differences in the angular distributions of top quarks and antiquarks produced at the LHC at energies of 7 and 8 TeV.

    Alas, individually and combined, their results show no deviation from the latest Standard Model calculations. These calculations have in fact recently been improved, and show that the predicted asymmetry is slightly higher than previously thought. This, along with improvements in data analysis, even brings the earlier Tevatron result into line with the Standard Model.

    ATLAS and CMS will continue to subject the heavyweight top quark to tests at energies of 13 TeV to see if it deviates from its expected behaviour, including precision measurements of its mass and interactions with other Standard Model particles. But measuring the asymmetry will get even tougher, because the effect is predicted be half as big at a higher energy. “It’s going to be difficult,” says Deliot. “It will be possible to explore using the improved statistics at higher energy, but it is clear that the space for new physics has been severely restricted.”

    The successful combination of the charge-asymmetry measurements was achieved within the LHC top-quark physics working group, where scientists from ATLAS and CMS and theory experts work together intensively towards improving the interplay between theory and the two experiments, explains CMS collaborator Thorsten Chwalek. "Although the combination of ATLAS and CMS charge asymmetry results didn't reveal any hints of new physics, the exercise of understanding all the correlations between the measurements was very important and paved the way for future ATLAS+CMS combinations in the top-quark sector.”

    For more inforrmation:

    Atlas webpage

    CMS webpage

    ATLAS physics briefing

     

     

     

    http://home.cern/about/updates/2017/10/atlas-and-cms-join-forces-tackle-top-quark-asymmetry

    ( Feed URL: http://home.web.cern.ch/about/updates/feed )

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  • Astronomy Picture of the Day for 2017-10-14 12:30:01.604840

    Astronomy Picture of the Day (Unofficial) at 2017-10-14T17:30:02Z

    Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

    2017 October 14
    See Explanation.  Clicking on the picture will download
 the highest resolution version available.

    All-Sky Steve
    Image Credit & Copyright: Alan Dyer, Amazingsky.com, TWAN

    Explanation: Familiar green and red tinted auroral emission floods the sky along the northern (top) horizon in this fish-eye panorama projection from September 27. On the mild, clear evening the Milky Way tracks through the zenith of a southern Alberta sky and ends where the six-day-old Moon sets in the southwest. The odd, isolated, pink and whitish arc across the south has come to be known as Steve. The name was given to the phenomenon by the Alberta Aurora Chasers Facebook group who had recorded appearances of the aurora-like feature. Sometimes mistakenly identified as a proton aurora or proton arc, the mysterious Steve arcs seem associated with aurorae but appear closer to the equator than the auroral curtains. Widely documented by citizen scientists and recently directly explored by a Swarm mission satellite, Steve arcs have been measured as thermal emission from flowing gas rather than emission excited by energetic electrons. Even though a reverse-engineered acronym that fits the originally friendly name is Sudden Thermal Emission from Velocity Enhancement, his origin is still mysterious.

    Tomorrow's picture: the origin of gold

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  • Diane Trout at 2017-10-13T17:50:48Z

    Hi Identi.ca.

    I feel like you need a sysadmin team, and enough funding to keep a sysadmin interested.

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    That would be good =)

    JanKusanagi at 2017-10-13T18:00:05Z

  • HPR2393: PWGen - A password generator

    PumpCast at 2017-10-04T00:14:02Z

    "HPR2393: PWGen - A password generator"

    • Download PWGen here
    • Download the 5 letter word list here

    http://hackerpublicradio.org/eps.php?id=2393

    ( Feed URL: http://hackerpublicradio.org/hpr_ogg_rss.php )

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  • The IceCube Collaboration meeting begins in Berlin

    ParticleNews at 2017-10-02T16:29:20Z

    "The IceCube Collaboration meeting begins in Berlin"

    The fall IceCube Collaboration meeting begins today in Berlin (Germany) hosted by the Humboldt University and DESY. More than 225 IceCube collaborators from around the globe will meet in person.

    http://icecube.wisc.edu/news/view/536

    ( Feed URL: http://icecube.wisc.edu/news/feed )

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