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Geoff Penington
3,318 posts
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Geoff Penington
@quantum_geoff
Associate Professor at Stanford. Quantum Information and Quantum Gravity. Currently at @Openai
Joined June 2017
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4,230
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  • Pinned
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    Geoff Penington
    @quantum_geoff
    May 26, 2021
    In 1993 the Superconducting Supercollider was cancelled. Estimated cost: $8 billion. An exodus of physicists left to Wall Street, bringing fancy maths and dubious risk management. 15 years later the global financial crisis cost ~$20 trillion. This is why you don't defund physics!
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    Geoff Penington
    @quantum_geoff
    Oct 9, 2024
    A lot of people are posting their thoughts on the physics Nobel prize. And I’m jet lagged and can’t sleep. So why not me too. First off, John Hopfield is a physicist, an outstanding one, whose work then branched out in various directions. Geoff Hinton is not. 1/
    138K
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    Geoff Penington
    @quantum_geoff
    Mar 14, 2025
    Image
    34K
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    Geoff Penington
    @quantum_geoff
    Sep 2, 2025
    I’m certainly not someone who tries to deny variation in people’s mathematical ability, but I genuinely believe any motivated person with a good teacher and no major learning disability could learn and understand matrix diagonalization in like 2 or 3 years max
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    Noah Smith 🐇🇺🇸🇺🇦🇹🇼
    @Noahpinion
    Sep 2, 2025
    "Why do we need to import all these scientists when we should be educating our OWN people" -- guy who could never learn how to diagonalize a matrix even if he had 10 years to study
    117K
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    Geoff Penington
    @quantum_geoff
    Oct 9, 2024
    Replying to @quantum_geoff
    Hopefully this is a sign than the Nobel prize committee will be taking a much broader view of what qualifies as important theoretical work in the future! But it seems slightly peculiar to start that trend with work that would be most naturally classified as computer science 7/7
    28K
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    Geoff Penington
    @quantum_geoff
    Mar 12, 2025
    It's certainly true that physicists underappreciate Emmy Noether's contributions to algebra. It's also true that mathematicians massively underappreciate how deep and fundamental "the symmetry result" is
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    Algebraic Geometer
    @BarbaraFantechi
    Mar 11, 2025
    A very restricted view. The symmetry result is what she is best known for BY PHYSICISTS. Her main contributions to mathematics are wider and fundamental. They also took the form not just of papers, but of discussions, lectures, and books by her students.
    19K
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    Geoff Penington
    @quantum_geoff
    Jan 9, 2025
    Superintelligence already exists and his name is Juan Maldacena
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    Tsarathustra
    @tsarnick
    Jan 6, 2025
    Sam Altman, in a new blog post, says "we are now confident we know how to build AGI" and OpenAI are "beginning to turn our aim beyond that, to superintelligence"
    27K
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    Geoff Penington
    @quantum_geoff
    Jun 20, 2025
    GOAT physics notes writer. Will probably be the GOAT physics textbook writer before he’s done
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    Superconformal Hassaan
    @Hassaan_PHY
    Jun 18, 2025
    David Tong is an asset to the world of theoretical physics. #physics #scicomm
    13K
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    Geoff Penington
    @quantum_geoff
    Oct 26, 2024
    Free fall is not gravity. That's just local inertial physics. Gravity is the force that causes your free fall trajectory and the Earth's free fall trajectory to approach one another at an accelerating rate. This is measurable with a device called an altimeter
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    Sabine Hossenfelder
    @skdh
    Oct 26, 2024
    The easiest way to see that gravity is not a force is to note that a force causes acceleration, but gravity does not. Acceleration is measurable with a device called an accelerometer. Acceleration is not relative (like velocity), it's absolute. If you are standing on the
    42K
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    Geoff Penington
    @quantum_geoff
    Oct 9, 2024
    Replying to @quantum_geoff
    He is an outstanding scientist, whose work has definitely been influenced by and influenced physics. But he’s not a physicist. That’s ok: Ed Witten isn’t a mathematician but he still won the Fields medal. 2/
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    Geoff Penington
    @quantum_geoff
    Aug 23, 2025
    No there isn't
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    Andrew Côté
    @Andercot
    Aug 22, 2025
    The one thing I've seen that's rock-solid on this topic is this: There is a way of producing FTL travel by manipulating spacetime local to the craft, and this is consistent with all of Einstein's GR AND the shape which minimizes the energy required is a flat saucer like disc🤷‍♂️
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    Geoff Penington
    @quantum_geoff
    Aug 18, 2025
    “Journalists have much better bullshit detectors”…a statement that could only be made by someone who has never read pop sci articles about a technical topic they know something about
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    Nate Silver
    @NateSilver538
    Aug 17, 2025
    Academic journals might be a lost cause but they'd probably be better if you had some non-academic practitioners serving as reviewers. Journalists have their problems too but they have much better bullshit detectors, for instance.
    10K
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    Geoff Penington
    @quantum_geoff
    Oct 9, 2024
    Replying to @quantum_geoff
    The theory needs to directly describe a specific physical system and then be experimentally verified. Hugely important theoretical work such as AdS/CFT or Witten’s work on confinement is treated as ineligible because the models being worked with don’t directly describe nature 5/
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    Geoff Penington
    @quantum_geoff
    Jan 4, 2025
    As someone who was on (two different) H-1B visas while an Assistant Professor at UC, Berkeley and a Visiting Professor at the Institute for Advanced Study, I certainly didn’t feel like an indentured servant. But maybe I secretly was?
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    Sen. Bernie Sanders
    @SenSanders
    Jan 2, 2025
    Elon Musk is wrong. The main function of the H-1B visa program is not to hire “the best and the brightest,” but rather to replace good-paying American jobs with low-wage indentured servants from abroad. The cheaper the labor they hire, the more money the billionaires make.
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