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...
Subscribe to the channel: / thelutetiumproject
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Visit our website: 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),
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),
videotheque.cnrs.fr/doc=264 (the language can be switched to english)
The serie of videos Grains de Bâtisseurs, of the Amàco (2015),
vimeo.com/channels/942027/173...
Jacques Duran, Sables émouvants, Belin (2003), in French,
www.belin-editeur.com/sables-...
Science étonnante #44, on the chaine ScienceEtonnante of David Louapre (2017), in French,
• La Science des Château...
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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,
blog.espci.fr/evelyne/home/
Collective Effects in Soft Matter team, Gulliver laboratory, for the high-speed camera www.ec2m.espci.fr/home/
Paul Boniface, Espace des Sciences Pierre-Gilles de Gennes,
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 - www.univ-psl.fr
ESPCI Paris - www.espci.fr
Espace des sciences Pierre-Gilles de Gennes - www.espgg.org
ESPCI Alumni - espci.alumni.paris
Fonds ESPCI Paris - www.fonds-espci-paris.org/