Spontaneous movements and linear response of a noisy oscillator F. Jülicher, K. Dierkes, B. Lindner, J. Prost and P. Martin Eur. Phys. J. E, 29 4 (2009) 449-460 Published online: 23 August 2009 DOI: 10.1140/epje/i2009-10487-5