Anomalous contribution to galactic rotation curves due to stochastic s

In summary, the paper discusses how stochastic processes, particularly the presence of small-scale structures and irregularities in dark matter distribution, can lead to anomalous contributions in galactic rotation curves. These contributions may help explain discrepancies observed between the predicted and measured rotational velocities of galaxies, suggesting that variations in dark matter density can significantly influence galactic dynamics. The findings highlight the importance of considering stochastic effects in cosmological models to better understand galaxy formation and behavior.
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TL;DR Summary
stochastic cosmological constant can explain galactic rotation curves without needing to evoke dark matter
Anomalous contribution to galactic rotation curves due to stochastic spacetime
Jonathan Oppenheim, Andrea Russo
Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics of Galaxies (astro-ph.GA); High Energy Physics - Theory (hep-th)


We consider a proposed alternative to quantum gravity, in which the spacetime metric is treated as classical, even while matter fields remain quantum. Consistency of the theory necessarily requires that the metric evolve stochastically. Here, we show that this stochastic behaviour leads to a modification of general relativity at low accelerations.
In the low acceleration regime, the variance in the acceleration produced by the gravitational field is high in comparison to that produced by the Newtonian potential, and acts as an entropic force, causing a deviation from Einstein's theory of general relativity. We show that in this "diffusion regime", the entropic force acts from a gravitational point of view, as if it were a contribution to the matter distribution.
We compute how this modifies the expectation value of the metric via the path integral formalism, and find that an entropic force driven by a stochastic cosmological constant can explain galactic rotation curves without needing to evoke dark matter. We caution that a greater understanding of this effect is needed before conclusions can be drawn, most likely through numerical simulations, and provide a template for computing the deviation from general relativity which serves as an experimental signature of the Brownian motion of spacetime. arXiv:2402.19459 [pdf, other]

another way to explain MOND in comparison to that produced by Deur self interactions with GR

how plausible ?
 
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Do you have a link to the paper?
 
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