Exponential potential versus dark matter

Newtonian Limit of String-Dilaton Gravity

“…Eckhardt [8] uses a combination of two exponential terms and gives a detailed explanation of the kinematics of galaxies and galaxy clusters, without dark matter models, using arguments similar to those of Sanders.…”

“…We have not fixed the gauge yet. Using the approximation (7), and the approximated expression of the scalar potential (8), the field equations (3) and (4) become, respectively,…”

Potential–density pairs for axisymmetric galaxies: the influence of scalar fields

“…In the past, different authors have used point solutions, Eq. (6), to solve the missing mass problem encountered in the rotation velocities of spirals and in galaxy cluster dynamics [15,16]. These models were used as an alternative to avoid dark matter.…”

“…There are stringent constraints on the possible λ-α values determined by measurements on local scales [14]. In the past the above solutions have been used to solve the missing mass problem in spirals [15,16] as an alternative to considering a distribution of dark matter. This was done assuming that most of the galactic mass is located in the galactic center, and then considering the center to be a point source.…”

Technique for Modeling the Gravitational Field of a Galactic Disk

“…Motivated by our interest in modeling the effect of an exponential potential (Eckhardt 1993), we have developed a Green's function for any potential that can be represented by a Laurent series. Such a general representation encompasses a Newtonian potential, a linear potential (Mannheim 1993), an exponential potential, a Yukawa potential, and just about any conceivable form for a potential.…”