I N-body simulation of high or low-mass dark matter particles

[Ranku]

Do we notice any significant difference in distribution and dynamics of dark matter in galaxies when n-body simulations are done with high or low-mass dark matter particles?

 

[phyzguy]

What do you mean by high or low mass? If you are thinking of resolving the mass of the DM particles this way, you need to know that the resolution of the simulations is nowhere near the level of being able to do this. I think the highest resolution n-body simulations have particle masses on the order of 10^4 to 10^5 Msun.

 

[Ranku]

What do you mean by high or low mass? If you are thinking of resolving the mass of the DM particles this way, you need to know that the resolution of the simulations is nowhere near the level of being able to do this. I think the highest resolution n-body simulations have particle masses on the order of 10^4 to 10^5 Msun.

I didn't know that the mass resolution is that low. Is it a computational limit, and therefore can improve?

 

[phyzguy]

Yes it is a computational limit. But 10^5 Msun is at least 50 orders of magnitude greater than a presumed DM particle, so don't hold you breath. Unless of course DM is primordial black holes...

 

[ohwilleke]

Lovell (2020) employs the EAGLE simulation to compare Warm Dark Matter (i.e. keV scale particles), Cold Dark Matter (i.e. GeV scale particles) and Self-Interacting Dark Matter models. https://arxiv.org/abs/2002.11129v1

The CLUE simulation compares WDM and CDM models in Yepes (2013). https://arxiv.org/abs/1312.0105

A survey of WDM to CDM comparisons by multiple means can be found in de Vega (2011). https://arxiv.org/abs/1109.3187

Axion-like Dark Matter (i.e. ultralight) and Cold Dark Matter models are compared in Marsh (2015) although most not by simulation methods. https://arxiv.org/abs/1510.07633