Podcast Summary: Más de uno – El reto matemático: La conjetura de Poincaré

Host: Carlos Alsina
Guests: Santi García Cremades, Aparici, Begoña
Date: February 12, 2026
Source: Onda Cero

Overview

In this engaging and humor-filled episode, Carlos Alsina is joined by mathematician Santi García Cremades and others to discuss the legendary mathematical puzzle known as the Poincaré Conjecture. The episode seamlessly interweaves the culture of mathematical challenges, anecdotes from the math and science community, and a new math challenge for listeners. A notable portion of the discussion pays tribute to Grigori Perelman’s mathematical feat, celebrating the enigmatic figure who solved one of the greatest problems of the 20th century.

Key Discussion Points and Insights

1. Mathematics in Daily Life and Family

• The episode opens with light banter about physicists, food, and social habits at conferences.
  • Santi jokes: “Tú vas a un congreso de física y no se relacionan socialmente mucho, pero cuando hay comida, de repente van como… Ha visto Walking Dead. Pues a mí me recuerda mucho ese.” [00:14]
• They highlight the importance and pleasure of sharing mathematical challenges within families, fostering generational learning.

2. Listener Participation: Resolving Last Week’s Challenge

• Santi celebrates a young listener’s solution to the previous week's math challenge:
  • Matías Jiménez Dinu (age 12, Logroño) shares his answer, prompted by his mother’s enthusiastic relay of the program’s riddles. [01:07]
  • Memorable quote from Santi: “Reto compartido en familia. Yo os quiero contar una historia.” [01:32]
• Hosts express delight at how the show encourages family engagement and critical thinking.

3. The Story of the Poincaré Conjecture and Grigori Perelman

• Santi narrates the captivating story of Grigori Perelman’s solution to the Poincaré Conjecture:
  • "Hace ya 20 años un tal Perelman... publicó en Internet sin pre ni ruedas de prensa... Grigori Perelman, único autor. La conjetura de Poincaré, que es uno de los siete problemas del milenio." [01:32]
• Explanation of the Conjecture:
  • Santi breaks down the abstract nature of the problem, using visual metaphors:
    • “Es como imaginar una esfera, una superficie cerrada, sin agujeros, un balón… cualquier lazo que hagas alrededor del balón puede encogerse hasta un punto...” [02:19]
    • He links the puzzle to higher dimensions: “...en cuatro dimensiones hablamos del universo con su tiempo, entonces hablamos de física, que esto Aparici también con los pelos de punta.” [02:32]
• Human side of Perelman:
  • Santi details how Perelman solved the problem in solitude and shunned fame, skipping the Fields Medal ceremony and rejecting the $1 million prize.
  • “A Perelman se le esperaba, se le invitó, pues ni apareció, ni concedió entrevistas.” [03:41]
  • Carlos jokes: “A ver si es que no existe.” [03:51]
  • Santi clarifies: “Vive con su mamá ahora, se dejó las matemáticas, es decir, lo hizo y dijo ya está.” [03:56]

4. This Week’s Math Challenge

• Santi brings a new riddle, inspired by car license plates:
  • “Una matrícula, cuatro dígitos, todos los dígitos distintos, sumando los extremos da 9, sumando los centrales también da 9... Si multiplica los dos primeros, da 30… es un número par.” [04:11]
• Listeners are encouraged to submit their solutions, continuing the interactive spirit of the show.

Notable Quotes and Memorable Moments

• On the unique culture of physicists at conferences:
  • Santi: “Tú vas a un congreso de física y no se relacionan socialmente mucho, pero cuando hay comida, de repente van como... Ha visto Walking Dead.” [00:14]
• Family learning and encouragement:
  • Santi: "Reto compartido en familia. Yo os quiero contar una historia." [01:32]
• Explaining Poincaré in “plain” language:
  • Santi: “Es como imaginar una esfera, una superficie cerrada, sin agujeros, un balón… cualquier lazo que hagas alrededor del balón puede encogerse hasta un punto.” [02:19]
• On Perelman’s rejection of fame:
  • Begoña (in amazement): “A ver si no existe, sí existe.” [03:52]
  • Santi: “Vive con su mamá ahora se dejó las matemáticas, es decir, lo hizo y dijo ya está.” [03:56]
• Setting the weekly challenge:
  • Santi: “Una matrícula, cuatro dígitos, todos los dígitos distintos… Si multiplica los dos primeros, da 30… es un número par, que si no hay dos dudas, pues es par. Venga, buscarlo.” [04:11]

Important Timestamps

• 00:14 — Discussion on physicists and food habits
• 01:07 — Young listener Matías solves last week's challenge
• 01:32 — Introduction to Perelman and the Poincaré Conjecture
• 02:19–02:40 — Accessible explanation of the conjecture
• 03:41–03:56 — Perelman’s character, life choices, and rejecting awards
• 04:11–05:15 — This week’s new math challenge announced

Conclusion

This episode of Más de uno blends humor, relatability, and profound awe for mathematical achievement. The story of Perelman and the Poincaré Conjecture is made accessible and engaging, with the hosts highlighting both the complexities of higher mathematics and the deeply human aspects of curiosity and recognition. As always, the episode ends with a new math puzzle for listeners, keeping minds sharp and families involved.