He studied at the Kunstakademie Düsseldorf from 1994 to 2000.
He makes sculptures based on space and astrophysics out of ordinary household materials. Between and 2011, Dahlem was a guest professor Berlin University of the Arts (UdK), Nuremberg Academy of Fine Arts, Karlsruhe Academy of Fine Arts and Braunschweig University of Artist Since 2012, he has been a professor for sculpture at the Braunschweig University of Artist
2000 German Handikraft (with John Bock and René Zeh), Auckland Artspace, Auckland, New Zealand 2001 Neue Modelle,Trafo gallery, Budapest 2002 Orgasmodrom, Galleria Giò Marconi, Milan 2003 Coma Sculptor, Friedrich Petzel Gallery, New York 2004 Kommando Pfannenkuchen, Daniel Hug Gallery, Los Angeles Heimweh, Haunch of Venison, London Solaris, University of California, Los Angeles Hammer Museum, Los Angeles Lost in Werner, The Modern Institute, Glasgow 2005 Printemps de Septembre, Festival of Contemporary Images, Toulouse S.N.O.W., Galerie Tucci Russo, Turin Strange Attractor, Gallery Hiromi Yoshii, Tokyo 2006 Extension Turn 2, Eastlink Gallery, Shanghai The Homunculus Saloon, Engholm Engelhorn Galerie, Vienna Busan Biennale, Museum of Modern Art, Busan, South of Korea Berlin goes Zürich, Arndt & Partner, Zurich 2007 Gallery Swap (Galerie Guido West Baudach, Berlin and Hotel, London),Hotel, London The Milky Way, Galerie Guido W. Baudach, Berlin.