B An old spin to our Universe

[.Scott]

TL;DR Summary

An automated survey of galactic spins has identified a preferred spin axis (3.39 sigma).

Lior Shamir reports an apparent preferred galactic spin axis based on his examination of data from the JWST Advanced Deep Extragalactic Survey (JADES). His report is available in an article in Monthly Notices of the Royal Astronomical Society.

The pattern is not subtle (N=263, sigma=3.39) and apparently, our Milky Way galaxy is bucking the trend. According to the abstract:

Analysis of spiral galaxies by their direction of rotation in JADES shows that the number of galaxies in that field that rotate in the opposite direction relative to the Milky Way galaxy is [about] 50 per cent higher than the number of galaxies that rotate in the same direction relative to the Milky Way.

This apparent spin preference had been noticed before. But in this new analysis, spin assessments were done automatically.

Also, I have marked this post as "Basic: High School Level", but that doesn't mean this thread needs to stay that way.

 

[Bandersnatch]

It's good to keep it in perspective - the paper analyses ~260 galaxies, within a fraction of a square degree of the sky, most of them within a 1 z radial range. Extrapolating this to the entire universe having a preferred spin is a bit premature, imho.

 

[.Scott]

It's good to keep it in perspective - the paper analyses ~260 galaxies, within a fraction of a square degree of the sky, most of them within a 1 z radial range. Extrapolating this to the entire universe having a preferred spin is a bit premature, imho.

Certainly it would be good to get more data from more of the celestial sphere.

In a another paper (JWST deep fields, March 2024, Astronomical Society of Australia), Shamir says this:

A proposed experiment that would complement this study is the analysis of the corresponding field imaged by JWST in the opposite hemisphere. In that field a higher number of galaxies that rotate counterclockwise can expected. If an axis formed by the distribution of spiral galaxies exist, it might not be centred at Earth (Shamir, Reference Shamir2022b), and therefore the distribution of spin directions in that field might not be exactly inverse to the distribution shown here. But if a higher number of counterclockwise galaxies is observed in that field, it would provide an indication of a consistent cosmological orientation towards a preferred direction, possibly forming a cosmological-scale axis. The proximity to the Galactic pole as well as to the CMB Cold Spot might also be possible directions for future research. JWST deep field images centred at the Galactic pole and at the CMB Cold Spot might provide additional information about the distribution of spiral galaxies in these parts of the sky to better understand the reasons leading to the anomaly.

He focused on the direction of the Milky Way "North Pole" because more accurate spin measurements can be gather at the poles. And there is no obvious reason to think that the Milky Way is pointing to a any kind of "preferred" direction.

 

[Bandersnatch]

There's no reason for any direction to be preferred, but there is a reason for small sample bias, or for galaxies sampled from the same cluster to have a preferred rotation direction due to conservation of angular momentum of the primordial overdensity. That's my intuition at least, fwiw.

I'm all for collecting pieces of the puzzle, but this paper looks a bit sensationalistic in how they dress up their results.

 

[.Scott]

I'm all for collecting pieces of the puzzle, but this paper looks a bit sensationalistic in how they dress up their results.

There is a tint of sensationalism. But I much appreciate his discussion on methodology and the detailed tracking of it to the results in sections 1 to 3) - which are presented in arrays of photos and tabulated.
By my estimate, section 4 is appropriate - providing a run down of what lead up to this. I appreciate context.
Section 5: OK. Sections 5.1 and 5.2: I suppose every researcher is allowed to plug his thoughts. I deliberately left that stuff out of my comments. But I would welcome discussion on that here.