The puzzling physics of sand

Sand, is it a solid or a liquid? ⏳ How come it flows, but we can walk on it? In this last video from The Lutetium Project, we explore the puzzling physics of sand!
↓ More infos and links in the description! ↓

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LINKS:

French version:    • La physique des tas de sable  
Subscribe to the channel:    / thelutetiumproject  
Follow us on Twitter:   / theluproject  
Visit our website: https://www.lutetium.paris/en

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RELATED PUBLICATIONS:

Étienne Guyon, Jean-Yves Delenne, and Farhang Radjai, Built on Sand, The MIT Press (2020),
https://mitpress.mit.edu/books/built-...

Pierre-Gilles de Gennes in The physics of the bag of marbles, on the video library of the CNRS (1997),
http://videotheque.cnrs.fr/doc=264 (the language can be switched to english)

The serie of videos Grains de Bâtisseurs, of the Amàco (2015),
https://vimeo.com/channels/942027/173...

Jacques Duran, Sables émouvants, Belin (2003), in French,
https://www.belin-editeur.com/sables-...

Science étonnante #44, on the chaine ScienceEtonnante of David Louapre (2017), in French,
   • La Science des Châteaux de Sable  

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STRUCTURE OF THE VIDEO:

00:00 Granulars: solids that flow
01:53 Vaulting and stable granular structures
03:11 Force chains
06:00 Dilatancy
07:05 Is sand a liquid, or a solid?

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CREDITS:

Host:
Julie Godefroid

Director:
Hoon Kwon

Writer:
Guillaume Durey

Science supervisor:
Pierre Jop

Animator:
Benjamin Alardin

Sound mixer:
Valentin Zorgnotti

Editor:
Guillaume Durey

Studio, visual identity:
Juliette Nier

Theme music:
Pierre David

Production:
Guillaume Durey, Mathias Kasiulis, Quentin Magdelaine

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ACKNOWLEDGEMENTS:

Evelyne Kolb, PMMH laboratory, for the photoelastic grains,
https://blog.espci.fr/evelyne/home/

Collective Effects in Soft Matter team, Gulliver laboratory, for the high-speed camera https://www.ec2m.espci.fr/home/

Paul Boniface, Espace des Sciences Pierre-Gilles de Gennes,
https://www.groupe-traces.fr/membre/p...

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The Lutetium Project is a PSL students’ initiative conducted as part of IDEX ANR-10-IDEX-0001-02 PSL and funded by:
PSL Research University – https://www.univ-psl.fr
ESPCI Paris – https://www.espci.fr
Espace des sciences Pierre-Gilles de Gennes – https://www.espgg.org
ESPCI Alumni – https://espci.alumni.paris
Fonds ESPCI Paris – https://www.fonds-espci-paris.org/