What do gas-rich galaxies actually tell us about modified Newtonian dynamics?

Abstract

It has recently been claimed that measurements of the baryonic Tully-Fisher relation (BTFR), a power-law relationship between the observed baryonic masses and outer rotation velocities of galaxies, support the predictions of modified Newtonian dynamics for the slope and scatter in the relation, while challenging the cold dark matter (CDM) paradigm. We investigate these claims, and find that: 1) the scatter in the data used to determine the BTFR is in conflict with observational uncertainties on the data; 2) these data do not make strong distinctions regarding the best-fit BTFR parameters; 3) the literature contains a wide variety of measurements of the BTFR, many of which are discrepant with the recent results; and 4) the claimed CDM "prediction" for the BTFR is a gross oversimplification of the complex galaxy-scale physics involved. We conclude that the BTFR is currently untrustworthy as a test of CDM.

5 pages, 2 figures; minor revisions to match published version

References in corpus (17)

• Modified Gravity and Cosmology
• The Baryonic Tully-Fisher Relation of Gas Rich Galaxies as a Test of LCDM and MOND
• The Universal Rotation Curve of Spiral Galaxies. II The Dark Matter Distribution out to the Virial Radius
• The Baryon Content of Extremely Low Mass Dwarf Galaxies
• Bimetric MOND gravity
• A Novel Test of the Modified Newtonian Dynamics with Gas Rich Galaxies
• The Tensor-Vector-Scalar theory and its cosmology
• A First Attempt to Calibrate the Baryonic Tully-Fisher Relation with Gas Dominated Galaxies
• The globular cluster NGC 2419: a crucible for theories of gravity
• Baryonic Tully-Fisher Relation for Extremely Low Mass Galaxies
• On the baryonic, stellar, and luminous scaling relations of disk galaxies
• The high mass end of the Tully-Fisher relation
• GHASP: an Hα kinematic survey of spiral and irregular galaxies -- IX. The NIR, stellar and baryonic Tully-Fisher relations
• The Radial Tully-Fisher relation for spiral galaxies I
• TeVeS gets caught on caustics
• Polytropic model fits to the globular cluster NGC 2419 in Modified Newtonian Dynamics
• Incompatibility of Rotation Curves with Gravitational Lensing for TeVeS

Cited by in corpus (8)

• Testing General Relativity in Cosmology
• Phantom of RAMSES (POR): A new Milgromian dynamics N-body code
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• An accurate measurement of the baryonic Tully-Fisher relation with heavily gas-dominated ALFALFA galaxies
• Unraveling the interplay between SIDM and baryons in MW halos: defining where baryons dictate heat transfer
• The Tully-Fisher relations for Hickson Compact Group galaxies
• Reconciliation of MOND and Dark Matter theory
• Tully-Fisher Relation of Late-type Galaxies at $0.6\le z\le 2.5$