Sign in

George A. Constantinides

@gconstantinides.bsky.social
629 followers 1.6K following 232 posts

Prof Digital Computation @imperialcollege, Director of the Early Career Researcher Institute. Vice Chair @iclmathsschool. Views own. constantinides.net.

PostsRepliesMedia
George A. Constantinides @gconstantinides.bsky.social · 23h
Very much enjoyed giving a talk to colleagues at @AMD alongside Kevin Buzzard on #leanprover and its implications for hardware verification (and design). Thanks for hosting, Theo Drane.
000
George A. Constantinides @gconstantinides.bsky.social · 03/10/2026
Looks like our @imperialeee.bsky.social undergrad Olly Cassidy (third from right) had a great time at IEEE SOCC where he was presenting some of our work on #FPGA LUT-based neural networks. Olly has significantly extended the work I started with Erwei Wang, Marta Andronic and collaborators.
020
George A. Constantinides @gconstantinides.bsky.social · 30/09/2026
Now on Palomar palomar-registry.org/entry?id=PAL...
palomar-registry.org
Registry entry — Palomar
001
George A. Constantinides @gconstantinides.bsky.social · 27/09/2026
Hong and Kung's 1981 red-blue pebble game, formalised this weekend for lean-misc-math, the Lean 4 library I curate. With S words of fast memory, an n-point FFT needs ≥ n log₂ n / (5 log₂ S) I/Os, and ordinary n × n matrix multiplication ≥ n³/(2√S). geoconuk.github.io/lean-misc-ma...
geoconuk.github.io
MiscMath.Computability.RedBluePebbleGame
000
George A. Constantinides @gconstantinides.bsky.social · 11/09/2026
Here's Oliver Cassidy presenting our work CascadeLUT at #FPL2026 in Ghent! (Joint with Marta Andronic and me) Paper: arxiv.org/abs/2608.00720
000
George A. Constantinides @gconstantinides.bsky.social · 11/09/2026
Beautiful result. Kolmogorov-Arnold, 1957: every continuous function on the unit cube is a superposition of univariate functions and addition, and the inner functions are fixed once for all f! Now formalised in lean-misc-math, the Lean 4 library I curate. geoconuk.github.io/lean-misc-ma...
030
George A. Constantinides @gconstantinides.bsky.social · 07/09/2026
Take n independent coins, a fixed expected number of heads. Which make the count most variable? The identical ones! Hoeffding 1956, new in lean-misc-math: at a fixed mean the binomial maximises E[g(S)] for every g convex on ℕ. github.com/geoconuk/lea...
github.com
GitHub - geoconuk/lean-misc-math: Miscellaneous classical and other mathematical results, formalised in Lean 4 on top of Mathlib
Miscellaneous classical and other mathematical results, formalised in Lean 4 on top of Mathlib - geoconuk/lean-misc-math
000
George A. Constantinides @gconstantinides.bsky.social · 03/09/2026
I spoke at an #ASAP2026 panel discussion on the last 40 years, chaired by Suhaib Fahmy. I highlighted that a major story has been the emergence of the systolic array described in the 1970s by Kung and block floating point, described in the 1950s by Wilkinson, into mainstream.
020
George A. Constantinides @gconstantinides.bsky.social · 23/08/2026
This is a cool project. I trialled it this weekend by refactoring one of my own little library's formalisations into the form required by Palomar. This was very efficiently accepted and registered: palomar-registry.org/entry?id=PAL...
palomar-registry.org
Registry entry — Palomar
000
George A. Constantinides @gconstantinides.bsky.social · 20/08/2026
Marta Andronic, Olivia Weng, Danial Zuberi, Ryan Kastner, for their poster "ConvLUT: Rethinking Convolutional Architectures for Ultra-Low-Latency LUT-Based Inference" (All joint with me) (4/4)
000
George A. Constantinides @gconstantinides.bsky.social · 20/08/2026
Filip Wojcicki, Omar Sharif, Ebby Samson, Paul Kelly, Christos Savvas Bouganis, Wayne Luk for their paper "Towards Small Language Models on FPGAs with PULSE: Perplexity-guided Low-precision Synthesis Explorer" (3/4)
100
George A. Constantinides @gconstantinides.bsky.social · 20/08/2026
Ebby Samson, Shane Fleming, Wayne Luk for their paper "PTQ-LUT: Post-Training Quantization into LUT-based Neural Networks" (2/4)
100
George A. Constantinides @gconstantinides.bsky.social · 20/08/2026
A bumper crop of papers accepted by #FPT2026. Congratulations to: Oliver Cassidy and Marta Andronic for their paper "ExitLUT: Boolean Early Exits for Efficient FPGA-Based Neural Network Inference" (1/4)
100
George A. Constantinides @gconstantinides.bsky.social · 16/08/2026
New in lean-misc-math, my Lean 4 library: Hoeffding's 1956 results on the number of successes in independent trials. Fix the mean. Among all independent trials with that mean, the binomial maximises E[g(S)] for every g convex on the integers. geoconuk.github.io/lean-misc-ma...
geoconuk.github.io
MiscMath.Probability.PoissonTrialsFixedMean
000
George A. Constantinides @gconstantinides.bsky.social · 12/08/2026
Looks like a great program for ASAP 2026 at @imperialcollegeldn.bsky.social. Come along in September to the talks, some great keynotes from Mitra (x2!), Yazdanbakhsh, Becker. Also a tutorial from our ARIA project and me holding forth on a panel 😀 2026.asap-conf.org/tentative-pr...
2026.asap-conf.org
Tentative Program Schedule – IEEE ASAP 2026 Conference
000
George A. Constantinides @gconstantinides.bsky.social · 09/08/2026
New: lean-misc-math, my own curated Lean 4 library of results not ready or too niche for Mathlib. First in: Wyner's 1967 spherical covering theorem. Proofs are machine-generated. github.com/geoconuk/lea...
github.com
GitHub - geoconuk/lean-misc-math: Miscellaneous classical and other mathematical results, formalised in Lean 4 on top of Mathlib
Miscellaneous classical and other mathematical results, formalised in Lean 4 on top of Mathlib - geoconuk/lean-misc-math
000
George A. Constantinides @gconstantinides.bsky.social · 03/08/2026
Some interesting ideas in the IEEE P3109 Interim Report on Binary Floating-point Formats for Machine Learning. Happy to have been able to play a small contributing role in this community effort. github.com/P3109/Public...
github.com
010
George A. Constantinides @gconstantinides.bsky.social · 30/07/2026
I noticed recently that the concept of a powerset lifting has come to the attention of Premier Inn. Now for the semantics.
000
George A. Constantinides @gconstantinides.bsky.social · 26/07/2026
Pretty sure this is unsatisfiable 😂
000
George A. Constantinides @gconstantinides.bsky.social · 16/07/2026
My review of my summer holiday reading, @sarahoconnorft.ft.com's "We are not Machines". Strong recommend. constantinides.net/2026/07/16/w...
constantinides.net
We Are Not Machines: Craft, Care and Collective Agency
Sarah O’Connor’s We Are Not Machines: The Fight for the Future of Work accompanied me on my summer holiday, but it has continued to unsettle how I think about work. It is an engaging, accessible bo…
043
Reposted by George A. Constantinides
Imperial Early Career Researcher Institute @imperialecri.bsky.social · 01/07/2026
A massive congratulations to all of our winners and a big thank you to everyone who presented or attended our #ECRShowcase today. Full professional photos from our event will be published early next week!
041
Reposted by George A. Constantinides
Imperial Early Career Researcher Institute @imperialecri.bsky.social · 01/07/2026
Our keynote speech is underway with Dr Gbemi Oluleye, Associate Professor in Sustainable Market Mechanisms, delivering her talk ‘‘The 3 C’s for Impact” to a lively audience
021
Reposted by George A. Constantinides
Imperial Early Career Researcher Institute @imperialecri.bsky.social · 01/07/2026
🚨 The #ECRShowcase results are in! First up: our Creativity Prize winners 🪄 Congratulations to: 🎖️Afraa Alzoubi Department of Bioengineering 🎖️Mario Miranda Department of Aeronautics 🎖️Sumesh Erikandath Dep of Civil & Environmental Engineering 🎖️Alexandra Yarger Department of Bioengineering
011
George A. Constantinides @gconstantinides.bsky.social · 24/06/2026
Back from beautiful Lausanne where I was a member of the jury for Ayatallah Elakhras' PhD "Efficient Data Steering in Dataflow Circuits". Congratulations to Aya! (Also to advisors Ienne and Josipović.) It was great working with Bourgeat, Campanoni, Falsafi and Zhang!
010
George A. Constantinides @gconstantinides.bsky.social · 18/06/2026
The top-level theorem of our formal proof of Wyner's theorem is here: github.com/bardia01/Dir... Wyner's 1967 paper is here: ieeexplore.ieee.org/document/677... (3/3)
github.com
Direction-Preserving-Number-Representations/PaperProofs/PaperProofs/Wyner.lean at main · bardia01/Direction-Preserving-Number-Representations
Contribute to bardia01/Direction-Preserving-Number-Representations development by creating an account on GitHub.
000
George A. Constantinides @gconstantinides.bsky.social · 18/06/2026
This is a super cool result, which Bardia Zadeh and I used in our 2026 work on efficient low precision number systems for machine learning! As part of the proof effort for that work, we formally proved Wyner's theorem in Lean FRO which may have independent interest. (2/3)
100
George A. Constantinides @gconstantinides.bsky.social · 18/06/2026
In 1967, Wyner's "Random Packings and Coverings of the Unit n-Sphere" showed that the number of spherical caps of angular radius theta required to cover an n-dimensional sphere asymptotically approaches exp[-n log sin theta + o(n)] as n increases. (1/3)
100
George A. Constantinides @gconstantinides.bsky.social · 11/06/2026
My latest (and probably final) blog post on block number formats and direction preservation. This time I deal with the number formats for scale factors. constantinides.net/2026/06/11/p...
constantinides.net
Precision Matters in Block Scales
This is the third post in a sequence relating to the geometry of block number formats as angle preservers. In my previous post, I argued that block number formats remain direction preservers even w…
000
George A. Constantinides @gconstantinides.bsky.social · 04/06/2026
The House of Commons Science, Innovation and Technology Committee has published my written submission to their inquiry "Low-energy computing" which means I am now free to publish it here: committees.parliament.uk/writtenevide...
committees.parliament.uk
010
George A. Constantinides @gconstantinides.bsky.social · 02/06/2026
I have written an accessible blog post on the recent preprint I published with Bardia Zadeh on taking a geometric view on what low precision means for vector representations, especially relevant to block arithmetics. constantinides.net/2026/06/02/d...
constantinides.net
Directionality in Low-Precision
In a couple of recent posts [1,2], I have been trying to reason through the geometric properties of block number formats. The basic idea is that when a group of numbers shares a scale factor, the s…
010
George A. Constantinides @gconstantinides.bsky.social · 02/06/2026
Congratulations again to my freshest @imperialcollegeldn.bsky.social PhD graduates who attended their ceremony at the Royal Albert Hall today. Here I am with Martin Langhammer and Benjamin Biggs. Celebrations all round!
030
George A. Constantinides @gconstantinides.bsky.social · 26/05/2026
I had the immense pleasure of joining colleagues from across Europe at University of Geneva last week for the LERU DOCT policy group. Delighted to have joined the group as a steering committee member. Looking forward to working with LERU and sharing the experience of @imperialecri.bsky.social!
000
George A. Constantinides @gconstantinides.bsky.social · 19/05/2026
Zadeh and I have uploaded a new preprint: Direction-Preserving Number Representations. Spoiler: FP is provably suboptimal but NVFP4 does a pretty good job! We have Lean proofs: Paper: arxiv.org/pdf/2605.07662 GitHub: github.com/bardia01/Dir...
arxiv.org
020
George A. Constantinides @gconstantinides.bsky.social · 17/05/2026
@ukparliament.parliament.uk Education SC has published my written submission to their inquiry "The use of Artificial Intelligence and EdTech in Education" which means I am now free to publish it. You can find all written submissions - including mine - at committees.parliament.uk/work/9642/th....
committees.parliament.uk
The use of Artificial Intelligence and EdTech in Education - Written evidence - Committees - UK Parliament
Written evidence submission publications for The use of Artificial Intelligence and EdTech in Education.
000
George A. Constantinides @gconstantinides.bsky.social · 05/05/2026
Congratulations to Jeffrey Wong, whose paper "A3: an Analytical Low-Rank Approximation Framework for Attention" with Zhang, Cao, Gimenes, Bouganis, Luk and Zhao has been accepted by ICLR 2026.
000
George A. Constantinides @gconstantinides.bsky.social · 22/04/2026
Interested in a PhD or postdoc in digital neuromorphic computing? @neural-reckoning.org, Christos Bouganis and I are recruiting! Please share with anyone who may be interested. Applications close on 15 May 2026. www.imperial.ac.uk/jobs/search-...
imperial.ac.uk
Description
Please note that job descriptions are not exhaustive, and you may be asked to take on additional duties that align with the key responsibilities ment...
021
George A. Constantinides @gconstantinides.bsky.social · 21/04/2026
Congratulations to my former PhD student Martin Langhammer on the acceptance of his paper "High Performance Multi-Processor Systems on FPGA" at HEART 2026
000
George A. Constantinides @gconstantinides.bsky.social · 21/04/2026
Had a great away day with the @imperialecri.bsky.social team yesterday at our White City campus. It was great to see the alignment in values coming through so strongly.
110
George A. Constantinides @gconstantinides.bsky.social · 31/03/2026
Her work on PolyLUT, NeuraLUT, and their extensions has set new standards in LUT-based neural networks. See arxiv.org/abs/2504.00592 for the latest work, and my blog constantinides.net for accessible introductions.
arxiv.org
NeuraLUT-Assemble: Hardware-aware Assembling of Sub-Neural Networks for Efficient LUT Inference
Efficient neural networks (NNs) leveraging lookup tables (LUTs) have demonstrated significant potential for emerging AI applications, particularly when deployed on field-programmable gate arrays (FPGA...
010
George A. Constantinides @gconstantinides.bsky.social · 31/03/2026
Huge congratulations to @martaandronic.bsky.social who yesterday passed her PhD viva with flying colours. Very positive comments from the examiners Kia Bazargan and Christos Savvas Bouganis. Marta has been a joy to supervise. (1/2)
110
George A. Constantinides @gconstantinides.bsky.social · 24/03/2026
Back from a lovely couple of days at the beautiful @edinburgh-uni.bsky.social, doing a PhD viva in Themis Prodromakis' group on machine-learning accelerators and then spending time with my collaborator Jianyi Cheng and his PhD student Chenyang Ai on egraphs.
000
George A. Constantinides @gconstantinides.bsky.social · 22/03/2026
Great thought-provoking lecture from Peter Hacker on Wittgenstein, hosted by The Royal Institute of Philosophy. With a wonderful ending "each generation must roll its own". There's a great need to "transform latent nonsense into patent nonsense" right now. www.youtube.com/watch?v=fcNE...
youtube.com
Wittgenstein and his impact upon Anglophone philosophy, Professor Peter Hacker
YouTube video by The Royal Institute of Philosophy
030
George A. Constantinides @gconstantinides.bsky.social · 18/03/2026
Spent today at a great @raeng.org.uk / LRF workshop on Sustainability and Safety at the Frontier of AI: A broad scoping exercise on what's coming by 2040 and how we get there. I emphasised need for algorithm / representation / architecture codesign. Also discussions on social / econ drivers in AI.
020
George A. Constantinides @gconstantinides.bsky.social · 16/03/2026
Attended my first meeting of the IEEE P3109 working group on Arithmetic Formats for Machine Learning today. Some interesting discussions - looking forward to more to come.
010
George A. Constantinides @gconstantinides.bsky.social · 16/03/2026
Happy British Philosophy Fortnight 2026. Much of my work involves questions about knowledge, abstraction, and value. Philosophy is everywhere. #philosophymatters
000
George A. Constantinides @gconstantinides.bsky.social · 15/03/2026
Block Number Formats are (Still!) Direction Preservers In a follow-up to my last blog post, here I show that even under coarse rounding of scaling factors to powers of two, block number formats can be considered direction preservers. constantinides.net/2026/03/15/b...
constantinides.net
Block Number Formats are (Still!) Direction Preservers
In my previous post, I argued that block number formats can be understood geometrically as direction preservers. That argument relied on an idealization: once a block direction had been chosen, its…
001
George A. Constantinides @gconstantinides.bsky.social · 11/03/2026
Spent a great morning with students and staff of Imperial Maths School. Highlight: student telling me that "here, if I am worried or concerned about something, people actually listen to me". Huge kudos to the maths school team.
010
George A. Constantinides @gconstantinides.bsky.social · 09/03/2026
Very useful clarity in this letter from UKRI to Chi Onwurah on funding - especially the Sankey diagram. committees.parliament.uk/publications...
committees.parliament.uk
021
George A. Constantinides @gconstantinides.bsky.social · 07/03/2026
Block Number Formats are Direction Preservers I've written a brief blog post about block number formats (MX, NVFP4, block floating point, block mini-floats, etc.) from a geometric perspective. constantinides.net/2026/03/07/b...
constantinides.net
Block Number Formats are Direction Preservers
I’ve recently returned from the SIAM PP 2026 conference and as always, conferences help provide time for research reflection. One thing I’ve been reflecting on during my journey back is…
000
George A. Constantinides @gconstantinides.bsky.social · 06/03/2026
This week I spoke at the SIAM PP 2026 conference in Berlin on the state of play of numerics, especially in AI / machine learning. More details on my talk and my slides are on here: www.linkedin.com/posts/george...
Berliner Fernsehturm
020