Declining Rotation Curves at High Redshift?

I was thinking of doing my own blog about a recent high-profile result published in Nature by Genzel et al. (and on the arXiv here), but then I see that Stacy McGaugh has already done a much more thorough and better-informed job than I would have done, so instead of trying to emulate his effort I’ll just direct you to his piece.

A recent paper in Nature by Genzel et al. reports declining rotation curves for high redshift galaxies. I have been getting a lot of questions about this result, which would be very important if true. So I thought I’d share a few thoughts here. Nature is a highly reputable journal – in most fields of […]

via Declining Rotation Curves at High Redshift? — Triton Station

P.S. Don’t ask me why WordPress can’t render the figures properly.

One Response to “Declining Rotation Curves at High Redshift?”

  1. In the Dark:

    Dark matter fractions decrease with increasing redshift because the resolution of spectroscopy requires redshift wavelength changes < 1 angstrom at Z < 0.001. At high-redshift, the spectroscopic resolution is acceptable. What this means is vanishing dark matter fractions at high-redshift shows dark matter does not exist even at Z << 0.001. Newtonian mechanics governs the Universe!

    But to show this is difficult as spectroscopy would have to be significantly improved. Even if so, any hope of showing this is difficult because galaxy velocities are dependent on redshift in cosmic dust. Perhaps, it is better to argue that the absence of dark matter at high-redshift also proves dark matter is absent at Z < 0.001.

    Also, the dependence of dark matter on the shape of rotation curves is an antiquated notion from the 1970's. See: "Existence of dark matter depends on cosmic dust, not the shape of rotation curves!" at, 2018


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: