In gratitude and memory of Claudi Alsina

BarcelonaToday the world of mathematics and its teaching has suffered a devastating blow. The death of Claudi Alsina leaves an immense void, one that is difficult to fill.

Claudi Alsina was not only a brilliant mathematician and educator; he was an inexhaustible source of enthusiasm, a bridge builder between ideas and people, a teacher with an extraordinary ability to make complex things seem simple. In fact, a teacher of teachers!

His gaze was always kind, but also lucid, curious, and lively. Where others saw meaningless numbers and equations, he saw stories connected to the everyday world. Where others saw formulas, he found poetry. Where others saw difficulties, he discovered opportunities for learning.

His career is immense: professor, prolific researcher, passionate popularizer, tireless lecturer, driving force behind projects and institutions, public servant, and mentor to generations of students and colleagues. But above all, Claudi Alsina was a humanist in the deepest and most beautiful sense of the word. He had that rare virtue of making everyone feel important, of standing alongside them rather than above them.

His impact is so vast it's difficult to grasp: more than fifty books, hundreds of articles, thousands of students influenced by his storytelling style, a thousand lectures that ignited vocations worldwide, and his brilliant contributions to the geometry of Gaudí. His academic and human legacy will remain with us forever.

Today we mourn his passing, but we also know that some people, when they leave, never truly go away. Claudi Alsina is one of these. His legacy will continue to live on in every student who discovered the magic of a theorem thanks to him, in every teacher who listened to him and left with a greater desire to transform, in every reader of his books who was surprised to find themselves loving mathematics without even realizing it.

He leaves us with an immense body of work and an even greater lesson: that knowledge is joy, that teaching is an act of love, and that curiosity is a precious way to live.

As he said: "Rigorous mathematics is done with the head and taught with the heart" (July 14, 1999).

Rest in peace. And may his light shine upon us forever.