Physicist. Founder and CEO @horizon_quantum. Former @quantumlah PI and associate professor. Slowly drifting south-east (Dublin-Oxford-Singapore).

Singapore
Joined July 2009
Delighted to be able to share that we expect to begin trading on Nasdaq tomorrow as $HQ. After 7 years of work, it’s great to finally reach the starting line. $DMYY horizonquantum.com/resources…
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Close, ChatGPT. Close.
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Sometimes Singapore is quite a cool place to live.
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Kicking myself that I shared an elevator ride with Erlich Bachman (well @nottjmiller) today and failed to recognise him despite the fact that an embarrassingly large amount of what I know about running a startup came from Silicon Valley.
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I don’t think the maths community is covering itself in glory with the reaction to recent AI results. If you believe that progress in mathematics is fundamentally important, it’s pretty hard to argue consistently against the application of any tool, including AI, to mathematics.
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That said, if researchers are being scooped by models trained on their private workings, that is much more problematic. I’d much rather see open weights models at the frontier of mathematics specifically because of the trust problem.
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Hands up if you also had an agent trying to determine the maximum number of MUBS in dimension six 🙋‍♂️
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I know we won't see two quantum Nobel prizes in a row, but it doesn't stop me from hoping to see a true quantum info one.
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Joe Fitzsimons retweeted
Replying to @letonyo
@grok what is the significance of having non-CSS codes of weight 10?
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It seems only yesterday that I was discussing with other physicists about when AI would be able to solve a Millennium problem ... but it was in fact two days ago.
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And, yes, of course I now have an agent trying to quantise gravity using pseudo-density matrices.
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Joe Fitzsimons retweeted
QIP 2027 is coming to Singapore! We’re proud to be the anchor sponsor for this event. Join us from February 20–26 to hear about the latest advances in quantum computing, cryptography, information theory, math, and physics. Learn more about @QIPConference qipconference.org/2027/
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Curious about Beryllium? We’ve a new blog post on the basics of the language.
What if quantum programming felt more like modern software development? Meet Beryllium—our purpose-built object-oriented quantum programming language. It brings familiar programming constructs to quantum software. Curious what that looks like? Read more👇 horizonquantum.com/resources…
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Delighted to be able to share that @horizon_quantum will be the anchor sponsor for QIP next year in Singapore. QIP is the premiere conference for the theoretical side of quantum information research, and it's a pleasure to see the event come back to Singapore.
We are excited to announce Horizon Quantum as the anchor sponsor for QIP 2027. Founded in 2018 by CQT alumnus Joe Fitzsimons, Horizon is a pioneer of software infrastructure for quantum applications, bridging the gap between today’s quantum hardware and tomorrow’s applications.
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I’m delighted to be able to share that Amanda Chew has been promoted to Chief Product Officer and will take up the new role later this month. Amanda joined us back in 2020 and has been instrumental in shaping the business and building the product org within @horizon_quantum.
It's been a privilege to work with the remarkable team at @horizon_quantum building the software infrastructure for programming quantum computers. I'm deeply grateful for what we're accomplishing and excited to build on this momentum, helping shape the future of quantum computing
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Joe Fitzsimons retweeted
Classes, function pointers, and libraries transformed classical software development. Beryllium brings them to quantum programming. Read on to learn what makes Beryllium different from other quantum programming frameworks. horizonquantum.com/resources…
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Joe Fitzsimons retweeted
Beryllium, our object-oriented programming language, lets developers build quantum programs with a rich type system. Check out this demo video to learn how to work with Beryllium’s primitive and composite datatypes, classes, modules, and more. youtube.com/watch?v=bbGIvvKt…
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Delighted to be collaborating further with @QuantumQM. We already use a Quantum Machines OPX 1000 controller in our Ember-1 testbed system, and I look forward to the companies working together to develop improved calibration for Ember-1 and beyond.
Today, we announced a strategic collaboration with @QuantumQM to increase the efficiency of quantum systems through the development of embedded calibration technologies designed to reduce downtime and improve operational stability. horizonquantum.com/resources…
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Nice piece on @peakxvpartners mentioning us. PeakXV (at the time Sequoia Capital India) were one of our early investors, leading our seed+ round, and are still a shareholder. Great partners throughout the journey and in my experience one of the few firms to truly back founders.
The first decisions often shape the longest journeys. ✔️The first product choices. ✔️The first hires. ✔️The first customers. ✔️The first markets. ✔️The design choices and hard decisions that shape everything after. At Surge, we partner with founders at this stage, with up to $5M in seed funding, dedicated investment team, company-building support and a community built for the early journey. If you’re building something truly ambitious, we’d love to hear from you! @madhavchanchani writes about Surge, our approach to seed investing, and what’s next in @thearc_hq . Read more: thearcweb.com/article/peak-x… @RajanAnandan @sjs_day1
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I'm pleased to share that we expect our second testbed system to be located in Dublin. This news comes the same week that Research Ireland announced a quantum research centre at Trinity College, so we're delighted to be contributing to Ireland's growing quantum ecosystem.
Today, we announced that we expect to locate our second quantum computer—an IonQ 256-qubit system—in Dublin, Ireland. By placing this frontier system in Ireland, we aim to benefit from the country’s growing quantum ecosystem and deep-tech talent pool. horizonquantum.com/resources…
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Ugh. Very first query on Fable got flagged because I asked about a lattice problem. It would be nice to have a non-nerfed version.
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