from Hacker News

Controversial new theory of gravity rules out need for dark matter

by Manheim on 3/9/24, 8:01 AM with 5 comments

• by BlueTemplar on 3/9/24, 12:41 PM

  > “In the absence of any direct evidence for dark energy or dark matter it is natural to wonder whether they may be unnecessary scientific constructs like celestial spheres, ether, or the planet Vulcan, all of which were superseded by simpler explanations,” it states. “Gravity has a long history of being a trickster.”

  Indeed (and not only gravity), so the Guardian is going too far here :

  > The proposition, outlined in a new paper, raises the controversial possibility that dark matter, which has never been directly observed, is a mirage that a substantial portion of the physics community has been chasing for several decades.

  This specific theory might be controversial, but the idea that we might eventually find a better explanation than dark matter - is not.

• by MattPalmer1086 on 3/9/24, 12:28 PM

  IANAC (I am not a cosmologist).

  However, what is interesting to me about this is that the MOND-like galactic rotation curves drop out of the theory.

  MOND itself didn't give any reason why gravity might behave differently. It was just a tweak that seemed to fit many observations. This theory seems to say that spacetime is inherently "wobbly", and this creates a difference from the classical picture in low acceleration regimes.

  The paper acknowledges that there is much more indirect evidence for dark matter than just the galactic rotation curves, but it is still an interesting theoretical approach.

• by blinding-streak on 3/9/24, 12:23 PM

  I have only a surface level understanding of dark matter and dark energy, but they both feel very unsatisfying to me. Sort of like a cheat code.

  I hope one of these new theories gains respectability.