In article , Eric Flesch
writes:

On Tue, 11 Apr 2017, Phillip Helbig wrote:
... (Eric Flesch) writes:
gravitational medium would modify or nullify the inverse square law.
How could it not? And that's pretty much all of my point.

... But the kind of dark matter we are talking about has little if
any interaction with baryonic matter.

Um, sorry Phil, but dark matter is supposed to account for (1) spiral
galaxy rotational profiles, and (2) "great attractors". Given the
existence of dark matter (for this argument), it definitely interacts
with baryonic matter.

Sorry: it has little if any interaction with baryonic matter OTHER THAN
GRAVITATIONAL INTERACTION. Thus, the buoyancy analogy doesn't work.

I'm not up with MOND. Is it simple?

Phenomenologically? Yes.

1. I think Phillip Helbig was referring to dark matter having little if
any *non-gravitational* interaction with baryonic matter.

Indeed.