RT Journal Article T1 On the dark energy rest frame and the CMB A1 Beltrán Jiménez, José A1 López Maroto, Antonio AB Dark energy is usually parametrized as a perfect fliud with negative pressure and a certain equation of state. Besides, it is supposed to interact very weakly with the rest of the components of the universe and, as a consequence, there is no reason to expect it to have the same large scale rest frame as matter and radiation. Thus, apart from its equation of state w and its energy density Q.DE one should also consider its velocity as a free parameter to be determined by observations. This velocity defines a cosmological preferred frame, so the universe becomes anisotropic and, therefore, the CMB temperature fluctuations will be affected, modifying mainly the dipole and the quadrupole. PB American Institute of Physics SN 0094-243x YR 2009 FD 2009 LK https://hdl.handle.net/20.500.14352/42673 UL https://hdl.handle.net/20.500.14352/42673 LA eng NO © 2009 American Institute of Physics. Spanish Relativity Conference (31st. 2008. Salamanca, Spain). We would like to thank the organizing committee of the Spanish Relativity Meeting ERE 2008 for their hospitality and exceUent organization. This work has been supported by DGICYT (Spain) project numbers EPA 2004-02602 and EPA 2005-02327, UCMSantander PR34/07-15875, CAM/UCM 910309 and MEC grant BES-2006-12059. NO Ministerio de Educación y Ciencia (MEC) NO Universidad Complutense de Madrid/Banco de Santander NO Comunidad de Madrid/Universidad Complutense de Madrid DS Docta Complutense RD 27 abr 2024