It always surprised me how lightly physicists treat infinity — anything “somewhat large” is susceptible of being treated as infinite. But infinity is conceptually very different from a large number.

Is the world at the fundamental level made of tiny indivisible pieces, or can it be divided ad infinitum? Perhaps our modern understanding of computation can shed some light on this ancient question. I gathered some thoughts for this book chapter. www.routledge.com/Quantum-Grav...

Per acompanyar la magnífica exposició sobre el temps comissariada pel @ricardsole.bsky.social, el Prof. Francis Garcia Collado ha organitzat un cicle de conferències a biblioteques sobre "Què és el temps?" pel gener i febrer de 2026. ajuntament.barcelona.cat/biblioteques...

El temps existeix realment o és tan sols una percepció? Quin és l'origen del temps? Per què percebem el temps només en una direcció? Les plantes poden preveure el fu...

Our new science exhibition “The Invention of Time” has just opened in Barcelona. Come explore time in physics, brains & life, from Evolution 2 relativity. We even have a working Time Machine (that’s me using it) @ibe-barcelona.bsky.social @icreacommunity.bsky.social museuciencies.cat/en/exposicio...

Now that festive times are approaching, and given our constant exposure to bad and sad news, it may be a good time to share two books I recently read which gave me hope in humankind: `Utopia for realists' and `Humankind’ by Rutger Bregman.

Informació de servei: No confieu en Correus. Vaig enviar un paquet certificat el setembre a Viena. No ha estat entregat, no se m'ha informat, ni se m'ha retornat. A més de no responsabilitzar-se'n, mala atenció personal a l'oficina. Per si us pot ajudar a decidir-vos per una altra empresa...😅

Els últims números de la revista Sàpiens i Petit Sàpiens estan dedicats a Franco. Han fet una feina fantàstica per recordar i aprendre, tant petits com grans, sobre aquella època tan fosca. Gràcies a tothom qui ho fa possible! Molt necessari pel país. www.sapiens.cat

L'altre dia vam tenir un bonic diàleg amb Eloi Planes sobre "Meravelles quàntiques i quotidianes" per Change2Grow. N'han publicat un resum detallat i correcte. Tan sols trobo estrany que sigui en castellà si tot l'acte va ser en català. www.c2gglobal.com/actualidad/c...

Quin article més bonic ha escrit Joan Borja sobre la conversa radiofònica amb Reis Juan per À Punt fa uns deu dies 🥰 ! M'alegro que les paraules trobessin un ressò dins d'aquesta persona. Gràcies per l'oportunitat @socreisjuan.bsky.social @julipereto.bsky.social alicanteplaza.es/alicanteplaz...

Gràcies per la bonica vetllada 😍

Alyssa Ney (metaphysician), Hans Briegel (theoretical physicist), Michele Catanzaro (science communicator) and myself will talk about Quantum Physics and Philosophy next Saturday Nov 22nd at 12:30 in El Born Centre Cultural, Barcelona. www.biennalciutaticiencia.barcelona/en/activitie...

I recently read "The order of time" and "Helgoland" by Carlo Rovelli and am very impressed by the rigour, sensitivity and depth with which he treats such fundamental topics. I feel like I learnt a lot. Much more than in the 4 introductions to metaphysics I had read.

Si la quàntica us fascina i us confón, i si sou a València el 19 de novembre, us pot interessar venir a sentir la conversa que mantindré amb Reis Juan a l'Octubre Centre de Cultura Contemporània. Gràcies a @julipereto.bsky.social per la iniciativa. octubre.cat/activitat/qu...

El divendres passat vam inaugurar la Setmana de la Ciència en una conversa, en la meva opinió molt bonica, al Parlament de Catalunya amb Alba Cervera Lierta i Sònia Fernàndez Vidal. Va ser un honor i un plaer gaudir d'una ocasió així. L'event es pot trobar aquí www.parlament.cat/ext/f?p=700:...

By the way, if you'd like to work with me in Barcelona, please get in touch and I can share funding options. E.g. if you are German and would like to do a PostDoc with me, one can consider the Feodor Lynen fellowship (as I am an Alexander von Humboldt alumnus).

In quantum theory, observables are associated to a vector space, and quantum states to a convex set. Observables can be thought of as questions, such as “Where is the quantum system?" States are something that answers these questions, albeit only probabilistically.

If you could travel through time — any era, any place — when would you go? Come imagine it with us, aboard our 1:1 Victorian time machine, at the upcoming exhibition “The Invention of Time” at Centre Martorell. Opening next Xmas! museuciencies.cat/en/the-nat/venues/centre-martorell-dexposicions/

What a wonderful book! The age of wonder, by Richard Holmes, tells the story of some early scientists and romantics from around 1800 -- mainly men and mainly British, centered on Joseph Banks, William Herschel and Humphry Davy. Very enjoyable. Thanks @ricardsole.bsky.social for the recommendation 😍

Why is universality such a central concept in complex systems? How does it connect Turing Machines and Spin Systems? In this new paper, Tomáš Gonda and @gemmadlc.bsky.social present an accessible account on how to identify and compare different universalities arxiv.org/pdf/2406.16607

Felicitats al @tonipou.bsky.social i al Diari @ara.cat per aquest magnífic article sobre la celebració dels primers 100 anys de la teoria quàntica. Quina situació tan emocionant i sorprenent! www.ara.cat/ciencia-medi...

A remarkable portrait of the confusion and diasagreement on the foundations of Quantum Mechanics. Thank you Elizabeth Gibney for the great questions and initiative! www.nature.com/articles/d41...

An enjoyable article by Charlie Wood for Quanta magazine, portraying some of the views in the Helgoland conference. Thanks for the careful work! Very important and necessary. www.quantamagazine.org/its-a-mess-a...

Universal spin models are universal approximators in Machine Learning. With Tobi Reinhart. arxiv.org/abs/2507.07669

Aquest acte de la Fundació Catalunya Cultura va ser preciós. Em va omplir d'esperança. I vaig estar ben agraïda de poder compartir alguns pensaments al costat de l'Eloi Planes. Gràcies, Bernat @puigtobella.bsky.social, per les paraules. www.nuvol.com/art/el-demo-...

I greatly enjoyed Anaximander, by Carlo Rovelli. "Anaximander opened the doors of Nature", said Pliny. In the sixth century BCE he proposed that the Earth is a stone floating in the void. And set the ball rolling for scientific instead of mythical cosmogonies.

Nice article about the conference in Helgoland physicsworld.com/a/helgoland-...

Andreas Klingler received a Prize for his PhD! I'm so happy. The prize was given by the Hypo Tyrol Bank. Congratulations, great job 😍 His PhD Thesis is available here www.andreas-klingler.com/publications

What a nice little video! Thank you Lizzie!

Gemma de les Coves being entirely honest from the start. #Helgoland2025

For some reason I am loving the experience of teaching Theory of Information at UPF... it is such a beautiful theory. And so recent, not even 100 years old. Many interesting lessons can be drawn from it.

One may think that all the secrets of a matrix can be read from its spectrum (and Jordan blocks, if needed). But this need not be the case. Sometimes you can't even tell if its moments will stay nonnegative forever. Joint work with Andreas Klingler, Joshua Graf & Tim Netzer doi.org/10.1016/j.la...

Last November we met in a monastery next to a lake in Sweden (Vadstena) to talk about the philosophy of physics, particularly quantum physics. It was wonderful. The talks are now available. www.philipgoyal.com/assets/websi...

I like seeing local physical interactions as the generative grammar of our physical world... For the Ising model, this idea can be made very precise, and prove if and only if theorems that characterize such grammar. Joint work with Tobi Reinhart. doi.org/10.1098/rspa...

L'altre dia vaig parlar amb l'Eli Tremps sobre inquietuds, la física, la filosofia i la poesia. Sobre el meu llibre i també la trajectòria. Va ser una conversa franca i agradable. Gràcies per l'oportunitat 😊 podcasts.apple.com/at/podcast/s...

Hi ha una llei segons la qual tothom qui vulgui es pot traduir nom o qualssevol dels cognoms al català. És fàcil de fer. Animo a qui se senti a disgust amb el seu nom o cognoms a fer-ho! Puc facilitar detalls de la llei i procediment.

An epistemic horizon is a limitation to what can be known. We derived such a horizon in a deterministic theory. Now published in Synthese. I hope next time we can publish such results in a community-run journal. link.springer.com/article/10.1...

Tobias Reinhart completed an excellent, thorough and excellently written PhD Thesis last month, entitled "Universality in Physics, Computer Science and Beyond". It can be found here: ulb-dok.uibk.ac.at/ulbtirolhs/c...

In 1925, Werner Heisenberg had the inspiration that marked the true dawn of quantum theory. A century on, quantum theory is here to stay. Read all about it: https://go.nature.com/3DzHM5v

I recently read "The structure of scientific revolutions" by Thomas Kuhn. I've been impressed and convinced by his arguments. They help me see the massive disagreements between interpretations of quantum theory in a new light, namely that of competing paradigms.

Fa poc vaig llegir el darrer llibre de Raül Garrigasait (@rgsait.bsky.social), La roca i l'aire, publicat per Fragmenta (@fragmentaed.bsky.social). No tan sols em va interessar molt, sinó que també em va commoure molt. Una preciosa aproximació al sagrat o inefable. Gràcies.

Ocean plastic debris is an environmental problem, but it is also the substrate for the so-called Plastisphere, a rich community of living species. Could some kind of collective system emerge from it, even a cognitive one? What are the constraints? Here's my drawing to think about it.

Last week Tobias Reinhart defended his PhD Thesis beautifully in Innsbruck! In a very clear talk, he managed to share the ideas and results, based on arxiv.org/abs/2407.13428 arxiv.org/abs/2307.06851 arxiv.org/abs/2208.08301 Congratulations!!! Great job.

Ranks can do surprising things, such as collapse in an arbitrarily small neighborhood. This work with Andreas Klingler and Tim Netzer has been finally published in Quantum 😊 quantum-journal.org/papers/q-202...

I love being back to Innsbruck 😍 I love this town. It’s so pretty!

Look what arrived today. It feels basically like being on the bill at Glastonbury.