From Stone Age to Modern Physics: A story of crack patterns!

The video of Jacques Pelegrin conference is now available!

We have invited at the “Physics laboratory of ENS-Lyon” Jacques Pelegrin (UMR “Prehistory and Technology”, Nanterre), experimentalist and expert in prehistoric lithic technology. Moreover, Mikko Alava (Aalto University, Finland), statistical physicist and expert in fracture mechanics, will also visit our laboratory as Visiting Professor at the University Lyon during April.

Therefore, this is an excellent opportunity to organize a workshop and gather both experimentalists and theoreticians working on the theme of “Pattern formation during the fracture of materials”.

Jacques Pelegrin is particularly interested in the various techniques of obsidian and flint cutting developed during prehistoric times, and specifically in the formation of conchoidal fracture patterns. Empirically, this type of fracture is surprisingly very controllable, however its physical parameters and modelling remain unknown.

The workshop will start by the seminar of Jacques Pelegrin, intended to raise many questions to materials physicists, and fracture experts. We will pursue with short presentations that may attempt to answer some of these questions, but surely will also bring new ones!


Figure: The 5 modes of silex knapping, depending on how the force is applied
[J. Pelegrin, 2012]




Figure: Series of large flint blades from the same block-or nucleus-: experimental reproduction of an operational chain observed in the Middle East (4000 to 1500 BC). The ruler is 20 cm long. [Test and Picture: J. Pelegrin]



Invited Speakers

- Mokhtar Adda-Bedia, LPS, ENS Paris

- Mikko Alava, Aalto University, Finland

- Marie-Julie Dalbe, Physics laboratory, ENS Lyon

- Davy Dalmas, SVI, St Gobain

- Jean-Christophe Géminard, Physics lab, ENS Lyon

- Véronique Lazarus, FAST, Orsay

- Jacques Pelegrin, UMR “Prehistory & Technology”, Nanterre

- Benoît Roman, PMMH, ESPCI

- Nicolas Vandenberghe, IRPHE, Marseille




- Stéphane Santucci, Physics laboratory, ENS Lyon

- Valérie Vidal, Physics laboratory, ENS Lyon


Administrative coordination

- Samantha Barendson, CBP - ENS Lyon

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