What is the standard interpretation for the anisotropy known as the CMB dipole?

Answer

Kinematic effect of our Solar System moving relative to the CMB rest frame

The CMB dipole represents the most recognized large-scale anisotropy in the Cosmic Microwave Background data, manifesting as a slight warming of the CMB in one direction and cooling in the opposite direction. Despite appearing to be a spatial asymmetry, the standard and accepted cosmological interpretation attributes this dipole entirely to kinematic effects. Specifically, it results from the velocity of our local cosmic neighborhood—including the Solar System and the Milky Way—moving at approximately 370 km/s relative to the reference frame of the CMB, which represents the average rest frame of the universe during the recombination era. This motion causes a Doppler shift in the observed CMB frequencies, distinguishing it from potential, more fundamental spatial anisotropies.

What is the standard interpretation for the anisotropy known as the CMB dipole?

Related Questions

What are the two structural components forming the Cosmological Principle?What property does isotropy imply when applied to all universe observers?Over what scale must averaging occur for the Cosmological Principle to hold?What dynamic solution emerges when CP combines with General Relativity?What analogy visualizes the expansion described by FLRW models?What observation provides the strongest empirical support for the Cosmological Principle?How does lookback time help resolve Olbers' Paradox regarding the dark night sky?What element does the Perfect Cosmological Principle add to the standard CP?Which reported structure tests the assumption of homogeneity due to its large size?What is the standard interpretation for the anisotropy known as the CMB dipole?
universecosmologyprincipleisotropy