Uploaded March 2026 | Updated September 2026, 1 week ago
Sabine Hossenfelder, Ivette Fuentes and James Ladyman discuss the scaling laws of the universe and the fundamental nature of reality.
Is the universe one thing, or many things?
With a free trial, you can watch the full debate NOW at iai.tv/video/the-one-and-the-many?utm_source=YouTube&utm_medium=description
A central question in ancient Greek philosophy was the problem of the One and the Many. It is a question that has echoed across Western culture and is still with us today. Should we see the world as a coherent whole or a multitude of separate parts? The puzzle is that we need both the whole and the parts, but an explanation of the relationship between them has proved problematic and perhaps unknowable. In contemporary physics, the parts are the teeming world of particle physics, and these should make up the cosmological world of the universe as a whole and the overall framework of Einsteinian space-time. But as yet we have not been able to combine the two coherently.
Is looking at the universe from the small scale and the large always going to be incompatible? Does it mean a theory of everything is an illusion and the attempt to combine quantum mechanics and Einstein’s general relativity a forlorn project? Or is the parallel with the ancient Greek puzzle accidental and the current challenge one that might be overcome?
#quantumphysics #universe #philosophy #fundamentalunits #theoryofeverything
Sabine Hossenfelder is a theoretical physicist and acclaimed science communicator, known for her sharp critiques of the scientific mainstream. She is also a best-selling author and YouTuber. Ivette Fuentes is a theoretical quantum physicist at the University of Southampton and Emmy Fellow at the University of Oxford. James Ladyman is a philosopher of science at the University of Bristol. He is best known for his book Every Thing Must Go, calling for a metaphysics grounded in physics and complexity science. Hosted by Jack Symes.
00:40 James Ladyman on the different notions of scale
02:39 Sabine Hossenfelder on energy in the universe
05:19 Ivette Fuentes on unifying quantum mechanics and general relativity
09:00 Is the universe "One" or "Many"?
17:15 Particles are not fundamental
The Institute of Art and Ideas features videos and articles from cutting edge thinkers discussing the ideas that are shaping the world, from metaphysics to string theory, technology to democracy, aesthetics to genetics. Subscribe today! iai.tv/subscribe?utm_source=YouTube&utm_medium=description&utm_campaign=the-one-and-the-many
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Sabine Hossenfelder, Ivette Fuentes and James Ladyman discuss the scaling laws of the universe and the fundamental nature of reality.
Is the universe one thing, or many things?
With a free trial, you can watch the full debate NOW at iai.tv/video/the-one-and-the-many?utm_source=YouTube&utm_medium=description
A central question in ancient Greek philosophy was the problem of the One and the Many. It is a question that has echoed across Western culture and is still with us today. Should we see the world as a coherent whole or a multitude of separate parts? The puzzle is that we need both the whole and the parts, but an explanation of the relationship between them has proved problematic and perhaps unknowable. In contemporary physics, the parts are the teeming world of particle physics, and these should make up the cosmological world of the universe as a whole and the overall framework of Einsteinian space-time. But as yet we have not been able to combine the two coherently.
Is looking at the universe from the small scale and the large always going to be incompatible? Does it mean a theory of everything is an illusion and the attempt to combine quantum mechanics and Einstein’s general relativity a forlorn project? Or is the parallel with the ancient Greek puzzle accidental and the current challenge one that might be overcome?
#quantumphysics #universe #philosophy #fundamentalunits #theoryofeverything
Sabine Hossenfelder is a theoretical physicist and acclaimed science communicator, known for her sharp critiques of the scientific mainstream. She is also a best-selling author and YouTuber. Ivette Fuentes is a theoretical quantum physicist at the University of Southampton and Emmy Fellow at the University of Oxford. James Ladyman is a philosopher of science at the University of Bristol. He is best known for his book Every Thing Must Go, calling for a metaphysics grounded in physics and complexity science. Hosted by Jack Symes.
00:40 James Ladyman on the different notions of scale
02:39 Sabine Hossenfelder on energy in the universe
05:19 Ivette Fuentes on unifying quantum mechanics and general relativity
09:00 Is the universe "One" or "Many"?
17:15 Particles are not fundamental
The Institute of Art and Ideas features videos and articles from cutting edge thinkers discussing the ideas that are shaping the world, from metaphysics to string theory, technology to democracy, aesthetics to genetics. Subscribe today! iai.tv/subscribe?utm_source=YouTube&utm_medium=description&utm_campaign=the-one-and-the-many
For debates and talks: iai.tv
For articles: iai.tv/articles
For courses: iai.tv/iai-academy/courses
