Of Particular Significance

A Catastrophic Weekend for Theoretical High Energy Physics

POSTED BY Matt Strassler

POSTED BY Matt Strassler

ON 08/06/2019

It is beyond belief that not only am I again writing a post about the premature death of a colleague whom I have known for decades, but that I am doing it about two of them.

Over the past weekend, two of the world’s most influential and brilliant theoretical high-energy physicists — Steve Gubser of Princeton University and Ann Nelson of the University of Washington — fell to their deaths in separate mountain accidents, one in the Alps and one in the Cascades.

Theoretical high energy physics is a small community, and within the United States itself the community is tiny.  Ann and Steve were both justifiably famous and highly respected as exceptionally bright lights in their areas of research. Even for those who had not met them personally, this is a stunning and irreplaceable loss of talent and of knowledge.

But most of us did know them personally.  For me, and for others with a personal connection to them, the news is devastating and tragic. I encountered Steve when he was a student and I was a postdoc in the Princeton area, and later helped bring him into a social group where he met his future wife (a great scientist in her own right, and a friend of mine going back decades).  As for Ann, she was one of my teachers at Stanford in graduate school, then my senior colleague on four long scientific papers, and then my colleague (along with her husband David B. Kaplan) for five years at the University of Washington, where she had the office next to mine. I cannot express what a privilege it always was to work with her, learn from her, and laugh with her.

I don’t have the heart or energy right now to write more about this, but I will try to do so at a later time. Right now I join their spouses and families, and my colleagues, in mourning.

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18 Responses

  1. Professor Matt Strassler is a great Human. Rest in peace the Heroes who sacrificed their Lives to infer Truths.

      1. High energy Physics and climbing mountains (conquering the Universe) is the same – towards lifeless mass-energy => space-energy = Naturalness.

  2. Indeed, a dark day for us all…that it should arise from such similar events is difficult to believe. I would like to take a moment away from that sorrow to extend my my thanks – broadly – to all such who invest thier whole lives (typically) to expanding the frontiers of human knowledge of this astonishing thing we all live in and experience daily, the Universe.
    I would also like to thank Dr Strassler specifically for devoting so much of his time to explaining (patiently!) so many aspects of the larger World to those of us without the background to ferret our way through the minutae which always accompanies deep Physics in general. Your time and efforts are sincerely appreciated by many I’m sure, as well myself distinctly.

  3. Max Planck: “*Science advances one funeral at a time. A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it*.”

    What is tragedy for person and lost for narrow branch of physics may become a blessing for science as a whole. Inverse AdS/CFT duality applies there.

    1. What an idiotic saying. Did the man have the slightest iota of proof for it? How many theories have risen in just our generation? Did all of cosmology die off in the 90s so the theory of dark energy could spread? Dark matter before it? Quarks before that? Foolishness.

  4. Knowing about the pain of loss I send my condolences to you and understand what a loss like these mean to you and your colleagues .

  5. Hello Matt.
    I share your grief. I did not know of Steve or Ann but feel your sense of loss. My condolences to their families.

  6. I met you at SUSY ’06 (then at U of Washington, still have your card), attended Ann Nelson’s talk (Saturday Plenary session):


    Click on pics/videos of Ann Nelson, then “Original Image”.

    There is panorama of Ann Nelson’s talk


    Again, click on “Original Image”

    I STILL remember Ann Nelson, I had no idea she had such a stellar reputation.

    She posted a panorama at 11:11am from mountain:


    Funny thing, on Sunday (Aug 4) I was ALSO engaging in some risky outdoor activity — challenging world-class (intermediate/advanced) single-track above JPL East parking lot..the famed El Prieto. I went UP (even more challenging), lots of exposure (steep dropoffs, 1 slip..injury or death). I’m kinda a novice at MTB’ing, my strength is bike mechanics (like building MTBs). To avoid risk (“Risk Management”), I got off the bike most of the time..just push-the-bike. I DID fall on a nasty off-camber, fortunately into tall grass. If it was a dropoff, I would have been in trouble. I made it to the top, then descended Lower Brown Mtn road. I saw a S&R (Search & Rescue) helicopter fly by, no doubt rescuing an injured party

    Even more coincidence, I got a text about from Caltech post-doc about my Trek 820 MTB for sale — while at 2019 SIGGRAPH conference last week (where AI & Deep Learning is a major factor, just as in Experimental Particle Physics — LHC data search). Turns out, his advisor is Dr Maria Spiropulu, who I also met at SUSY ’06. He also does MTB’ing above JPL, I sold him a Trek 820

    Ann had commented on the M87 black-hole imaging breakthrough (Dr Katie Bouman, et al)


    Katie was a featured speaker at 2019 SIGGRAPH, she just started at Caltech. She is a MIT CSAIL (Computer Science Artificial Intelligence Lab) — Computer Vision, AI, Robotics. This was my PhD field (U of Illinois, AARG “Advanced Automation Research Group” — AI/Vision/Robotics), 1 of my research contemporaries was Dr Wil Grimson (MIT CSAIL), who is pioneer in remote medical tele-robotics (he was MIT Chancellor recently)

    ^^^^ Strange coincidental convergence of various SUSY ’06 attendees. AI & Deep Learning is penetrating MANY fields, & is a current interest of mine.

    See below 3 hr course (“Deep Learning: A Crash Course”) by Dr Andrew Glassner from 2019 SIGGRAPH

  7. I share in your mourning, Matt. The premature death of anybody is always sad – but the deaths of these two people, who were “bright lights” of the Particle Physics community, makes their deaths particularly sad.

  8. So sorry to hear this Matt. Of course I did not know them, but I can share in your mourning for premature death of “bright lights” in the Particle Physics community.

  9. Sorry, but to be gifted with such a brilliant mind and then take unnecessary risks, regardless of how small, is beyond me. The irony is the ultimate adventure is exactly what they were trained to do, theoretical high-energy physics.

    My condolences to the families and their friends. RIP

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