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.

  • Ben Sturmfels at 2018-07-20T11:05:31Z

    Haven't posted to pump.io for a bit, but still enjoying checking in every day or so to see what's happening!

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  • Astronomy Picture of the Day for 2018-07-20 12:30:02.383693

    Astronomy Picture of the Day (Unofficial) at 2018-07-20T17:30:03Z

    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.

    2018 July 20
    See Explanation.
Moving the cursor over the image will bring up an annotated version.
Clicking on the image will bring up the highest resolution version
available.

    The Teapot and the Milky Way
    Image Credit & Copyright: Kerry-Ann Lecky Hepburn (Weather and Sky Photography)

    Explanation: The recognizable stars of the Teapot asterism in the constellation Sagittarius posed with the Milky Way over Death Valley, planet Earth on this quiet, dark night. The surreal scene was appropriately captured from Teakettle Junction, marked by the wooden sign adorned with terrestrial teapots and kettles on the rugged road to Racetrack Playa. Shining against the luminous starlight of the central Milky Way is bright planet Saturn, just above the star at the celestial teapot's peak. But the brightest celestial beacon, high above the southern horizon, is an orange tinted Mars at upper left in the frame.

    Tomorrow's picture: from another world

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  • Astronomy Picture of the Day for 2018-07-15 12:30:01.435673

    Astronomy Picture of the Day (Unofficial) at 2018-07-15T17:30:02Z

    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.

    2018 July 15
    See Explanation.  Clicking on the picture will download
the highest resolution version available.

    Rings Around the Ring Nebula
    Image Credit: Hubble, Large Binocular Telescope, Subaru Telescope; Composition & Copyright: Robert Gendler

    Explanation: There is much more to the familiar Ring Nebula (M57), however, than can be seen through a small telescope. The easily visible central ring is about one light-year across, but this remarkably deep exposure - a collaborative effort combining data from three different large telescopes - explores the looping filaments of glowing gas extending much farther from the nebula's central star. This remarkable composite image includes narrowband hydrogen image, visible light emission, and infrared light emission. Of course, in this well-studied example of a planetary nebula, the glowing material does not come from planets. Instead, the gaseous shroud represents outer layers expelled from a dying, sun-like star. The Ring Nebula is about 2,000 light-years away toward the musical constellation Lyra.

    Open Science: Browse 1,700+ codes in the Astrophysics Source Code Library
    Tomorrow's picture: cosmological neutrino

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  • First 3D colour X-ray of a human using CERN technology

    ParticleNews at 2018-07-10T13:28:33Z

    "First 3D colour X-ray of a human using CERN technology"

    Timepix3, one of the read-out chips of Medipix (Image: CERN)

    What if, instead of a black and white X-ray picture, a doctor of a cancer patient had access to colour images identifying the tissues being scanned? This colour X-ray imaging technique could produce clearer and more accurate pictures and help doctors give their patients more accurate diagnoses.

    This is now a reality, thanks to a New-Zealand company that scanned, for the first time, a human body using a breakthrough colour medical scanner based on the Medipix3 technology developed at CERN. Father and son scientists Professors Phil and Anthony Butler from Canterbury and Otago Universities spent a decade building and refining their product.

    Medipix is a family of read-out chips for particle imaging and detection. The original concept of Medipix is that it works like a camera, detecting and counting each individual particle hitting the pixels when its electronic shutter is open. This enables high-resolution, high-contrast, very reliable images, making it unique for imaging applications in particular in the medical field.

    Hybrid pixel-detector technology was initially developed to address the needs of particle tracking at the Large Hadron Collider, and successive generations of Medipix chips have demonstrated over 20 years the great potential of the technology outside of high-energy physics.

    MARS Bioimaging Ltd, which is commercialising the 3D scanner, is linked to the University of Otago and Canterbury. The latter together with more than 20 research institutes forms the third generation of Medipix collaboration. The Medipix3 chip is the most advanced chip available today and Professor Phil Butler recognises that “this technology sets the machine apart diagnostically because its small pixels and accurate energy resolution mean that this new imaging tool is able to get images that no other imaging tool can achieve.”

    MARS’ solution couples the spectroscopic information generated by the Medipix3 enabled detector with powerful algorithms to generate 3D images. The colours represent different energy levels of the X-ray photons as recorded by the detector hence identifying different components of body parts such as fat, water, calcium, and disease markers.

    A 3D image of a wrist with a watch showing part of the finger bones in white and soft tissue in red. (Image: MARS Bioimaging Ltd)

    So far, researchers have been using a small version of the MARS scanner to study cancer, bone and joint health, and vascular diseases that cause heart attacks and strokes. “In all of these studies, promising early results suggest that when spectral imaging is routinely used in clinics it will enable more accurate diagnosis and personalisation of treatment,” Professor Anthony Butler says.

    CERN's Knowledge Transfer group has a long-standing expertise in transferring CERN technologies, in particular for medical applications. In the case of the 3D scanner, a license agreement has been established between CERN, on behalf of Medipix3 collaboration and MARS Bioimaging Ltd. As Aurélie Pezous, CERN Knowledge Transfer Officer states, “It is always satisfying to see our work leveraging benefits for patients around the world. Real-life applications such as this one fuels our efforts to reach even further.”

    In the coming months, orthopaedic and rheumatology patients in New Zealand will be scanned by the revolutionary MARS scanner in a clinical trial that is a world first, paving the way to a potentially routine use of this new generation equipment.

    https://home.cern/about/updates/2018/07/first-3d-colour-x-ray-human-using-cern-technology

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

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  • One (Decentralized) Cloud to Rule Them All

    Blaise Alleyne at 2018-07-05T16:51:17Z

    I love Nextcloud. I really love Nextcloud.

    5 years ago, I was running so many different applications that have just been replacing by Nextcloud apps.

    • SOGO (CalDAV/CardDAV) => Nextcloud Calendar/Contacts
    • Snowy (Tomboy notes sync) => Nextcloud Grauphel
    • Tiny Tiny RSS => Nextcloud News
    • Roundcube => Nextcloud RainLoop

    Plus, I've just been playing around with Nextcloud Talk which offers an easy-to-use Hangsouts-like WebRTC video chat.

    I really love Nextcloud.

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  • We need to talk about the Higgs

    ParticleNews at 2018-07-04T07:28:35Z

    "We need to talk about the Higgs"

    François Englert (left) and Peter Higgs at CERN on 4 July 2012, on the occasion of the announcement of the discovery of a Higgs boson (Image: Maximilien Brice/CERN)

    It is six years ago that the discovery of the Higgs boson was announced, to great fanfare in the world’s media, as a crowning success of CERN’s Large Hadron Collider (LHC). The excitement of those days now seems a distant memory, replaced by a growing sense of disappointment at the lack of any major discovery thereafter.

    While there are valid reasons to feel less than delighted by the null results of searches for physics beyond the Standard Model (SM), this does not justify a mood of despondency. A particular concern is that, in today’s hyper-connected world, apparently harmless academic discussions risk evolving into a negative outlook for the field in broader society. For example, a recent news article in Natureled on the LHC’s “failure to detect new particles beyond the Higgs”, while The Economistreported that “Fundamental physics is frustrating physicists”. Equally worryingly, the situation in particle physics is sometimes negatively contrasted with that for gravitational waves: while the latter is, quite rightly, heralded as the start of a new era of exploration, the discovery of the Higgs is often described as the end of a long effort to complete the SM.

    Let’s look at things more positively. The Higgs boson is a totally new type of fundamental particle that allows unprecedented tests of electroweak symmetry breaking. It thus provides us with a novel microscope with which to probe the universe at the smallest scales, in analogy with the prospects for new gravitational-wave telescopes that will study the largest scales. There is a clear need to measure its couplings to other particles – especially its coupling with itself – and to explore potential connections between the Higgs and hidden or dark sectors. These arguments alone provide ample motivation for the next generation of colliders including and beyond the high-luminosity LHC upgrade.

    So far the Higgs boson indeed looks SM-like, but some perspective is necessary. It took more than 40 years from the discovery of the neutrino to the realisation that it is not massless and therefore not SM-like; addressing this mystery is now a key component of the global particle-physics programme. Turning to my own main research area, the beauty quark – which reached its 40th birthday last year – is another example of a long-established particle that is now providing exciting hints of new phenomena (see Beauty quarks test lepton universality). One thrilling scenario, if these deviations from the SM are confirmed, is that the new physics landscape can be explored through both the b and Higgs microscopes. Let’s call it “multi-messenger particle physics”.

    How the results of our research are communicated to the public has never been more important. We must be honest about the lack of new physics that we all hoped would be found in early LHC data, yet to characterise this as a “failure” is absurd. If anything, the LHC has been more successful than expected, leaving its experiments struggling to keep up with the astonishing rates of delivered data. Particle physics is, after all, about exploring the unknown; the analysis of LHC data has led to thousands of publications and a wealth of new knowledge, and there is every possibility that there are big discoveries waiting to be made with further data and more innovative analyses. We also should not overlook the returns to society that the LHC has brought, from technology developments with associated spin-offs to the training of thousands of highly skilled young researchers.

    The level of expectation that has been heaped on the LHC seems unprecedented in the history of physics. Has any other facility been considered to have produced disappointing results because only one Nobel-prize winning discovery was made in its first few years of operation? Perhaps this reflects that the LHC is simply the right machine at the right time, but that time is not over: our new microscope is set to run for the next two decades and bring physics at the TeV scale into clear focus. The more we talk about that, the better our long-term chances of success.

    _____________

    This text first appeared in the March 2018 issue of the CERN Courier.

    https://home.cern/about/updates/2018/07/we-need-talk-about-higgs

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

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  • 456: High Energy Physicist Studying Particle Collisions and Cosmic Rays - Dr. Daniel Whiteson

    PumpCast at 2018-07-02T07:14:58Z

    "456: High Energy Physicist Studying Particle Collisions and Cosmic Rays - Dr. Daniel Whiteson"

    Dr. Daniel Whiteson is a Professor of Physics and Astronomy at the University of California, Irvine. He is also co-author of the book We Have No Idea: A Guide to the Unknown Universe. As a particle physicist, Daniel is working to discover how the universe began and what things are made of at their most fundamental levels. When not in the lab, Daniel engages in experimental baking to create a wide variety of desserts. He’s currently perfecting his recipe for chocolate babka, a type of sweet bread. Regardless of how his kitchen experiments turn out, it’s fun to share them with his wife and two kids. Daniel received his B.S. in Physics and Computer Science from Rice University, he was awarded a Fulbright Fellowship to study at the Niels Bohr Institute in Copenhagen, and he went on to earn his PhD in Physics from the University of California, Berkeley. He conducted postdoctoral research afterwards at the University of Pennsylvania before joining the faculty at UC, Irvine. Daniel has received various awards and honors in his career, including an Alfred P. Sloan Foundation Fellowship, an Outstanding Junior Investigator award from the U.S. Department of Energy, the Chancellor’s Award for Excellence in Undergraduate Research from UC, Irvine, and a Webby Award in Experimental and Innovation sites for developing a smartphone app called Cosmic Rays Found in Smartphones which uses a cell phone’s camera to detect ultra high-energy cosmic rays. Daniel has also been named a Fellow of the American Physical Society. Daniel joined us for an interview to talk more about his life and science.

    http://peoplebehindthescience.libsyn.com/456-high-energy-physicist-studying-particle-collisions-and-cosmic-rays-dr-daniel-whiteson

    ( Feed URL: http://peoplebehindthescience.libsyn.com/rss )

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  • Astronomy Picture of the Day for 2018-07-03 12:30:02.321086

    Astronomy Picture of the Day (Unofficial) at 2018-07-03T17:30:03Z

    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.

    2018 July 3
    See Explanation.  Clicking on the picture will download
the highest resolution version available.

    An Airplane in Front of the Moon
    Image Credit & Copyright: Ji-Hoon Kim

    Explanation: If you look closely at the Moon, you will see a large airplane in front of it. Well, not always. OK, hardly ever. Actually, to capture an image like this takes precise timing, an exposure fast enough to freeze the airplane and not overexpose the Moon -- but slow enough to see both, a steady camera, and luck -- because not every plane that approaches the Moon crosses in front. Helpful equipment includes a camera with fast continuous video mode and a mount that automatically tracks the Moon. The featured fleeting superposition was captured from Seoul, South Korea two weeks ago during a daytime waxing gibbous moonrise. Within 1/10th of a second, the airplane crossing was over.

    Follow APOD on: Facebook, Google Plus, Instagram, or Twitter
    Tomorrow's picture: flashy rocket launch

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  • JanKusanagi at 2018-07-02T12:22:14Z

    T_T


    Hopefully, ActivityPub federation isn't too far off!

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  • pump.saz.im and Pumpa development shutting down

    sazius at 2018-07-02T10:55:28Z

    I've decided to shut down my home server at the end of August (i.e., in about two months). This also means, unfortunately, that my pump.io server pump.saz.im will go down, thus ending my presence on pump.io. I know I could move to one of the public pump.io servers out there, but I'm also trying to consolidate my "social media" presence - and Mastodon seems to be winning out for me. You can find me on Mastodon as sazius@soc.ialis.me. (I've also recently deleted my Twitter and Facebook accounts, of course for even better reasons...)

    This decision also means that I'm no longer actively maintaining or developing Pumpa, the Qt-based pump.io client that I created. It doesn't make sense for me to work on something that I don't use anymore. If anyone is interested in continuing Pumpa development, I would definitely be open to transferring maintainership. Anyway, the source code will always be out there if anyone wants to use it. For a good and actively maintained pump.io desktop client, I recommend people instead use Dianara by @JanKusanagi.

    It has been fun over here, and I still love the community. Perhaps we can link up again once the ActivityPub flows (or pumps) all around :-)

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    T_T


    Hopefully, ActivityPub federation isn't too far off!

    JanKusanagi at 2018-07-02T12:22:14Z

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    Yes, I'm also eagerly waiting for that day!

    sazius at 2018-07-02T18:06:00Z

  • Astronomy Picture of the Day for 2018-07-01 12:30:01.901980

    Astronomy Picture of the Day (Unofficial) at 2018-07-01T17:30:03Z

    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.

    2018 July 1
    See Explanation.  Clicking on the picture will download
the highest resolution version available.

    Fresh Tiger Stripes on Saturn's Enceladus
    Image Credit: NASA, ESA, JPL, SSI, Cassini Imaging Team

    Explanation: Do underground oceans vent through the tiger stripes on Saturn's moon Enceladus? Long features dubbed tiger stripes are known to be spewing ice from the moon's icy interior into space, creating a cloud of fine ice particles over the moon's South Pole and creating Saturn's mysterious E-ring. Evidence for this has come from the robot Cassini spacecraft that orbited Saturn from 2004 to 2017. Pictured here, a high resolution image of Enceladus is shown from a close flyby. The unusual surface features dubbed tiger stripes are visible in false-color blue. Why Enceladus is active remains a mystery, as the neighboring moon Mimas,approximately the same size, appears quite dead. A recent analysis of ejected ice grains has yielded evidence that complex organic molecules exist inside Enceladus. These large carbon-rich molecules bolster -- but do not prove -- that oceans under Enceladus' surface could contain life.

    News: Complex Organics Bubble up from Ocean-world Enceladus
    Tomorrow's picture: deep sky colors

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  • JanKusanagi at 2018-06-27T13:41:03Z

    ALL TRAINS??!!!

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  • Astronomy Picture of the Day for 2018-06-20 12:30:02.126524

    Astronomy Picture of the Day (Unofficial) at 2018-06-20T17:30:03Z

    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.

    2018 June 20
    See Explanation.  Clicking on the picture will download
the highest resolution version available.

    Pillars of the Eagle Nebula in Infrared
    Image Credit: NASA, ESA, Hubble, HLA; Processing: Llus Romero

    Explanation: Newborn stars are forming in the Eagle Nebula. Gravitationally contracting in pillars of dense gas and dust, the intense radiation of these newly-formed bright stars is causing surrounding material to boil away. This image, taken with the Hubble Space Telescope in near infrared light, allows the viewer to see through much of the thick dust that makes the pillars opaque in visible light. The giant structures are light years in length and dubbed informally the Pillars of Creation. Associated with the open star cluster M16, the Eagle Nebula lies about 6,500 light years away. The Eagle Nebula is an easy target for small telescopes in a nebula-rich part of the sky toward the split constellation Serpens Cauda (the tail of the snake).

    APOD Event: APOD Editor to speak at Fermilab on August 8
    Tomorrow's picture: pixels in space

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    AAAH!!! THEY'RE GONNA KILL US!!

    JanKusanagi at 2018-06-20T18:31:55Z

  • pump.io meeting today!

    AJ Jordan at 2018-06-18T10:45:19Z

    Forgot to announce this over the weekend but there's a last-minute pump.io meeting today, June 18th! 5 PM PST/8 PM EST and everyone is welcome!

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    Please share! https://github.com/pump-io/pump.io/wiki/Community for details on where to find us :)

    AJ Jordan at 2018-06-18T10:48:38Z

    So... 12AM UTC? (+1 if we're already counting DST)


    Community page.

    JanKusanagi at 2018-06-18T12:24:00Z

  • Astronomy Picture of the Day for 2018-06-16 12:30:01.582492

    Astronomy Picture of the Day (Unofficial) at 2018-06-16T17:30:02Z

    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.

    2018 June 16
    See Explanation.  Clicking on the picture will download
the highest resolution version available.

    Dusty With a Chance of Dust
    Image Credit: NASA, JPL-Caltech, MSSS, Curiosity Mars Rover

    Explanation: It's storm season on Mars. Dusty with a chance of dust is the weather report for Gale crater as a recent planet-scale dust storm rages. On June 10 looking toward the east-northeast crater rim, the Curiosity rover's Mastcam captured this image of its local conditions so far. Meanwhile over 2,000 kilometers away, the Opportunity rover ceased science operations as the storm grew thicker at its location on the west rim of Endeavour crater, and has stopped communicating, waiting out the storm for now. Curiosity is powered by a radioisotope thermoelectric generator, but the smaller Opportunity rover uses solar panels to charge its batteries. For Opportunity, the increasingly severe lack of sunlight has caused its batteries to run low.

    Tomorrow's picture: and more dust

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    » Astronomy Picture of the Day (Unofficial):

    “[...] Tomorrow's picture: and more dust [...]”

    xDD

    JanKusanagi at 2018-06-17T14:22:51Z

  • sazius at 2018-06-16T20:15:34Z

    Right, it's ActivityPub not Pump... I like pubs better than pumps anyway ;-)

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  • JanKusanagi at 2018-06-12T23:46:21Z

    Iiiit's raaaining at CEEERN!! Hallellujah, it's raining at CEEERN!!!!


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  • Astronomy Picture of the Day for 2018-06-11 12:30:01.581337

    Astronomy Picture of the Day (Unofficial) at 2018-06-11T17:30:02Z

    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.

    2018 June 11
    See Explanation.  Clicking on the picture will download
the highest resolution version available.

    At Last GLAST
    Image Credit: NASA, DOE, Fermi Gamma-ray Space Telescope Collaboration

    Explanation: Rising through a billowing cloud of smoke, a long time ago from a planet very very close by, this Delta II rocket left Cape Canaveral Air Force Station's launch pad 17-B at 12:05 pm EDT on June 11, 2008. Snug in the payload section was GLAST, the Gamma-ray Large Area Space Telescope. GLAST's detector technology was developed for use in terrestrial particle accelerators. So from orbit, GLAST can detect gamma-rays from extreme environments above the Earth and across the distant Universe, including supermassive black holes at the centers of distant active galaxies, and the sources of powerful gamma-ray bursts. Those formidable cosmic accelerators achieve energies not attainable in earthbound laboratories. Now known as the Fermi Gamma-ray Space Telescope, on the 10 year anniversary of its launch, let the Fermi Science Playoffs begin.

    Tomorrow's picture: pixels in space

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  • Manual Data Entry Device

    at 2018-06-12T01:40:01Z

    Keep one always around =)

    AJ Jordan, sazius, Ben Sturmfels, Stephen Sekula and 4 others likes this.

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  • Astronomy Picture of the Day for 2018-06-10 12:30:01.608577

    Astronomy Picture of the Day (Unofficial) at 2018-06-10T17:30:02Z

    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.

    2018 June 10
    See Explanation.  Clicking on the picture will download
the highest resolution version available.

    The Cat's Eye Nebula from Hubble
    Image Credit: NASA, ESA, HEIC, and The Hubble Heritage Team (STScI/AURA)

    Explanation: To some, it may look like a cat's eye. The alluring Cat's Eye nebula, however, lies three thousand light-years from Earth across interstellar space. A classic planetary nebula, the Cat's Eye (NGC 6543) represents a final, brief yet glorious phase in the life of a sun-like star. This nebula's dying central star may have produced the simple, outer pattern of dusty concentric shells by shrugging off outer layers in a series of regular convulsions. But the formation of the beautiful, more complex inner structures is not well understood. Seen so clearly in this digitally sharpened Hubble Space Telescope image, the truly cosmic eye is over half a light-year across. Of course, gazing into this Cat's Eye, astronomers may well be seeing the fate of our sun, destined to enter its own planetary nebula phase of evolution ... in about 5 billion years.

    Tomorrow's picture: a long time ago

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