Recent content by timmdeeg

Perhaps this helps: https://www.astro.ucla.edu/~wright/cosmology_faq.html#MX Are galaxies really moving away from us or is space just expanding? This depends on how you measure things, or your choice of coordinates. In one view, the spatial positions of galaxies are changing, and this causes...

Thanks, to me its hard to see though how 1) and 2) result in a dark matter halo without visible matter.

... around the bulge, yes. From here we start. The Bullet Cluster shows that even after collisions of Galaxies dark matter is still around visible matter. So, how can visible matter, e.g. the bulge of a galaxy, get rid off its halo of dark matter?

The main mass of a galaxy is located in its bulge. In this case separation is hard to imagine, isn't it?

As I understand it, many observations show that dark matter is gravitationally bound to visible matter. Supposed this dark matter halo has existed initially together with visible matter, are there mechanism thinkable wich could separate both types of matter?

Agreed. My comment is related to the title of the Thread, not to Black holes evaporation, which makes things more complicated.

Isn't the core of all these posts that these two spacetimes, the one where something crosses the event horizon in its proper time and the other one, where it doesn't even reach in coordinate time the event horizon in finite time the fact that the principle of simultaneity just can't be applied...

Thank you for your helpful comments, as always.

So quite fruitless. If I remember correctly you stated somewhere here some time ago that only an exact solution of the EFE modelling a Galaxie could clarify this matter. I wonder why proponents of gravitational field self-interaction haven't presented such a solution till now. Too difficult?

Ok, thanks. So one could conclude that the physical content isn't very convincing. Or people don't read it at all because field self-interaction in general is judged as being a negligible effect.

https://arxiv.org/pdf/2503.09804 From the abstract: ... Our derivation uses both EE and the Newtonian approximation of EE in Part I, to describe semi-classically in Part II the advection of DM, created at the level of the universe, into galaxies and clusters thereof. This advection happens...

As an aside here is another attempt to get rid of Dark Matter in Galaxies. "Exact solutions for differentially rotating galaxies in general relativity" / https://arxiv.org/pdf/2406.14157 abstract: "Whether or not abundant collisionless dark matter exists, the new solutions very strongly...

The more it is astonishing that these physicists seem to overlook this factor. Thanks for answering.

https://www.mdpi.com/2571-712X/8/3/65 In short, if the dynamics of spiral galaxies are dependent on galactic morphology in the way predicted by GR-SI, and the morphology of galaxies are correlated with their number of satellite galaxies (and more generally, their environment), then we expect to...

Thanks to both of you for clarifying my question.