The Missing Mass Problem

[steve_bank]

Came to mind on a region thread.

From my 70s astronomy class at the tie there was a question of the misting mass of the universe.

Depending on them mass assigned the universe could be oscillatory, steady state, or an expansion followed by a collapse IOW one cycle. Or so9ethng like that.

The term "missing mass" in the context of 1970s astrophysics refers to the discrepancy between the amount of mass astronomers could observe in the universe and the amount of mass they knew must be present based on its gravitational effects.

In the 1970s, astronomers observed that galaxies rotated faster than expected based on the visible matter they contained, leading to the concept of "missing mass". This missing mass, now known as dark matter, is a mysterious form of matter that interacts gravitationally but does not emit or absorb light.

Cosmology's Missing Mass Problems

Brief overview of cosmology's missing mass problems followed by a trip back to the 1920's for a partial solution, capped by the author's variable electric charge hypotheis as a means of explaining cosmological redshift

shadetreephysics.com

Cosmology's Missing Mass Problems

Robert S. Fritzius
Shade Tree Physics
Installed as a web page on 27 Jun 2003. Latest update 10 Apr 2019.
Text additions or changes are in bold.
Parts 1 - 7 have been incorporated into a single file.

This research has made use of NASA's Astrophysics Data System (NADS) Bibliographic Services.
The first Missing Mass Problem
In 1933 Fritz Zwicky was the first to find a need to invoke the idea of missing mass or dark matter. He looked at eight Coma galaxies. By assuming visual equilibrium,* he calculated the mass-to-light ratio and determined that about 90% of the mass necessary to account for the observed ratio was missing and therefore invisible. or "dark." Here, the apparent rapid velocities of the galaxies, with respect to their common center of mass, suggested that much more mass (than could be seen) was required to keep the galaxies from flying out of the cluster. (BVSD) [Link no longer works.]

*Visual equilibrium means that the amount of light (of stars) is proportional to amount of mass (number of stars).

In 1936 Sinclair Smith found similar evidence for the existence of invisible mass in the Virgo cluster. [An outline of the Virgo cluster can be seen in the lower left polar plot of the Star Map in Galactic Perspective]

In 1940 Oort estimated (based on the Mass-to-light ratio of spiral nebulae) that 90% of the mass in the local group of spiral nebulae is "missing." Oort didn't cite Zwicky's 1933 paper (BSVD).

Dark Matter 101: Looking for the Missing Mass - NASA Science

Here’s the deal — here at NASA we share all kinds of amazing images of planets, stars, galaxies, astronauts, other humans, and such, but those photos can only

science.nasa.gov

What is dark matter? We don’t really know. That’s not to say we don’t know anything about it – we can see its effects on ordinary matter. We’ve been getting clues about what it is and what it is not for decades. However, it’s hard to pinpoint its exact nature when it doesn’t emit light our telescopes can see.
The first hint that we might be missing something came in the 1930s when astronomers noticed that the visible matter in some clusters of galaxies wasn’t enough to hold the cluster together. The galaxies were moving so fast that they should have gone zinging out of the cluster before too long (astronomically speaking), leaving no cluster behind.

I am not knowledgeable in astronomy but it shows how scientific thought evolves on a problem. Sometimes generational.

 

[bilby]

Did they check Your Mom?