The Most Misunderstood Concept in Physics

From 1veritasium, 2veritasium, or sciencium.

One of the most important, yet least understood, concepts in all of physics. Head to to start your free 30-day trial, and the first 200 people get 20% off an annual premium subscription.

If you’re looking for a molecular modeling kit, try Snatoms – a kit I invented where the atoms snap together magnetically:

A huge thank you to those who helped us understand different aspects of this complicated topic – Dr. Ashmeet Singh, Supriya Krishnamurthy, Dr. Jos Thijssen, Dr. Bijoy Bera, Dr. Timon Idema, Álvaro Bermejillo Seco and Dr. Misha Titov.

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Harnessing The True Power Of Atoms | Order And Disorder Documentaries, Spark via YouTube –

A better description of entropy, Steve Mould via YouTube –

Dugdale, J. S. (1996). Entropy and its physical meaning. CRC Press. –

Schroeder, D. V. (1999). An introduction to thermal physics. –

Fowler, M. Heat Engines: the Carnot Cycle, University of Virginia. –

Chandler, D.L. (2010). Explained: The Carnot Limit, MIT News –

Entropy, Wikipedia –

Clausius, R. (1867). The mechanical theory of heat. Van Voorst. –

What is entropy? TED-Ed via YouTube –

Thijssen, J. (2018) Lecture Notes Statistical Physics, TU Delft.

Schneider, E. D., & Kay, J. J. (1994). Life as a manifestation of the second law of thermodynamics. Mathematical and computer modelling, 19(6-8), 25-48. –

Lineweaver, C. H., & Egan, C. A. (2008). Life, gravity and the second law of thermodynamics. Physics of Life Reviews, 5(4), 225-242. –

Michaelian, K. (2012). HESS Opinions" Biological catalysis of the hydrological cycle: life’s thermodynamic function". Hydrology and Earth System Sciences, 16(8), 2629-2645. –

England, J. L. (2013). Statistical physics of self-replication. The Journal of chemical physics, 139(12), 09B623_1. –

England, J. L. (2015). Dissipative adaptation in driven self-assembly. Nature nanotechnology, 10(11), 919-923. –

Wolchover, N. (2014). A New Physics Theory of Life, Quantamagazine –

Lineweaver, C. H. (2013). The entropy of the universe and the maximum entropy production principle. In Beyond the Second Law: Entropy Production and Non-equilibrium Systems (pp. 415-427). Berlin, Heidelberg: Springer Berlin Heidelberg. –

Bekenstein, J.D. (1972). Black holes and the second law. Lett. Nuovo Cimento 4, 737–740. –

Carroll, S.M. (2022). The Biggest Ideas in the Universe: Space, Time, and Motion. Penguin Publishing Group. –

Black hole thermodynamics, Wikipedia –

Cosmology and the arrow of time: Sean Carroll at TEDxCaltech, TEDx Talks via YouTube –

Carroll, S. M. (2008). The cosmic origins of time’s arrow. Scientific American, 298(6), 48-57. –

The Passage of Time and the Meaning of Life | Sean Carroll (Talk + Q&A), Long Now Foundation via YouTube –

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Written by Casper Mebius, Derek Muller & Petr Lebedev
Edited by Trenton Oliver & Jamie MacLeod
Animated by Mike Radjabov, Ivy Tello, Fabio Albertelli and Jakub Misiek
Filmed by Derek Muller, Albert Leung & Raquel Nuno
Molecular collisions video by CSIRO’s Data61 via YouTube: Simulation of air
Additional video/photos supplied by Getty Images, Pond5 and by courtesy of NASA, NASA’s Goddard Space Flight Center, NASA Goddard Flight Lab/ CI Lab, NASA/SDO and the AIA, EVE, HMI, and WMAP science teams. As well as the Advanced Visualization Laboratory at the National Center for Supercomputing Applications, B. Robertson, L. Hernquist
Music from Epidemic Sound & Jonny Hyman
Produced by Derek Muller, Petr Lebedev, Emily Zhang, & Casper Mebius