Test of the Einstein equivalence principle with spectral distortions in the cosmic microwave background

Abstract

The Einstein Equivalence Principle~(EEP) can be verified by the measurement of the spectral distortions of the Cosmic Microwave Background (CMB). The existence of energy-dependency in the cosmological redshift effect means the EEP violation. Introducing the energy-dependent Friedmann-Robertson-Walker metric motivated by rainbow gravity, we show that the energy-dependent redshift effect causes the CMB spectral distortions. Assuming the simple energy-dependent form of the metric, we evaluate the distortions. From the COBE/FIRAS bound, we find that the deviation degree from the EEP, which is comparable to the difference of the parameterized-post-Newtonian parameter "gamma" in energy, is less than 10^{-9} at the CMB energy scale.

4 pages, 1 figure, title revised, references added, minor changes to match PRD published version

References in corpus (15)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• Tests of general relativity with GW150914
• Effect of Primordial Black Holes on the Cosmic Microwave Background and Cosmological Parameter Estimates
• Probing modifications of General Relativity using current cosmological observations
• Testing Einstein's Equivalence Principle with Fast Radio Bursts
• The Effects of Dark Matter-Baryon Scattering on Redshifted 21 cm Signals
• Breaking of the equivalence principle in the electromagnetic sector and its cosmological signatures
• Rainbow universe
• Constraints on Primordial Black Holes by Distortions of Cosmic Microwave Background
• Limits on Einstein's Equivalence Principle from the first localized Fast Radio Burst FRB 150418
• On Testing the Equivalence Principle with Extragalactic Bursts
• Testing the Running of non-Gaussianity through the CMB mu-distortion and the Halo Bias
• Tests of the Einstein Equivalence Principle using TeV Blazars
• CMB $\mu$ distortion from primordial gravitational waves
• Testing the wavelength dependence of cosmological redshift down to $\Delta z\sim 10^{-6}$

Cited by in corpus (2)

• Redshift and lateshift from homogeneous and isotropic modified dispersion relations
• Tests of General Relativity: A Review