TeVeS/MOND is in harmony with gravitational redshifts in galaxy clusters

TL;DR

This paper demonstrates that MONDian models, specifically TeVeS, can explain galaxy cluster gravitational redshifts as well as general relativity with dark matter, challenging previous claims that ruled out TeVeS.

Contribution

The authors show that MONDian isothermal sphere models are consistent with observed gravitational redshifts, countering prior analyses that favored general relativity.

Findings

MONDian models fit redshift data as well as dark matter models.

Previous analyses used unjustified mass profiles for clusters.

Confusion between TeVeS and MOND functions affected earlier conclusions.

Abstract

Wojtak, Hansen and Hjorth have recently claimed to confirm general relativity and to rule out the tensor-vector-scalar (TeVeS) gravitational theory based on an analysis of the gravitational redshifts of galaxies in 7800 clusters. But their ubiquitous modeling of the sources of cluster gravitational fields with Navarro-Frenk-White mass profiles is neither empirically justified out to the necessary radii in clusters, nor germane in the case of TeVeS. Using MONDian isothermal sphere models consistently constructed within MOND (equivalent to TeVeS models), we can fit the determined redshifts no worse than does general relativity with dark halos. Wojtak, Hansen and Hjorth's work is further marred by confusion between the primitive mu-function of TeVeS and the MOND interpolation function.