Free Republic
Browse · Search
General/Chat
Topics · Post Article

Skip to comments.

In rotating galaxies, distribution of normal matter precisely determines gravitational acceleration
Science Daily ^ | September 21, 2016 | Case Western Reserve University

Posted on 09/22/2016 3:59:44 PM PDT by sparklite2

Now a team led by Case Western Reserve University researchers has found a significant new relationship in spiral and irregular galaxies: the acceleration observed in rotation curves tightly correlates with the gravitational acceleration expected from the visible mass only.

"Galaxy rotation curves have traditionally been explained via an ad hoc hypothesis: that galaxies are surrounded by dark matter," said David Merritt, professor of physics and astronomy at the Rochester Institute of Technology, who was not involved in the research. "The relation discovered by McGaugh et al. is a serious, and possibly fatal, challenge to this hypothesis, since it shows that rotation curves are precisely determined by the distribution of the normal matter alone. Nothing in the standard cosmological model predicts this, and it is almost impossible to imagine how that model could be modified to explain it, without discarding the dark matter hypothesis completely."

(Excerpt) Read more at sciencedaily.com ...


TOPICS: Astronomy
KEYWORDS: galaxies; gravity
Navigation: use the links below to view more comments.
first previous 1-2021-33 last
To: slouper

Who cares? People who are invested in the existence of black matter,
astrophysicists, and people who are interested in science.
This is huge.


21 posted on 09/22/2016 5:07:33 PM PDT by sparklite2 (The game overs whether you play it or not.)
[ Post Reply | Private Reply | To 20 | View Replies]

To: sparklite2

Damn, I did it again. Black = dark.


22 posted on 09/22/2016 5:08:36 PM PDT by sparklite2 (The game overs whether you play it or not.)
[ Post Reply | Private Reply | To 21 | View Replies]

To: mjp

black matter lives.


23 posted on 09/22/2016 6:22:37 PM PDT by AndyJackson
[ Post Reply | Private Reply | To 9 | View Replies]

To: sparklite2

Sparklite2, is this really “breaking news”? I ask because, if I recall correctly, these observations were discussed by Timothy Ferris in his book entitled The Whole Shebang, copyright 1997. I am not a scientist, not even an amateur one, but I did enjoy Ferris’ book.


24 posted on 09/22/2016 6:34:39 PM PDT by fortes fortuna juvat (The Democrats are so lacking in class, especially the avant-garde.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: sparklite2

I always considered dark matter analogous to the ancient aether: a convenient construction to explain what could not objectively be explained.


25 posted on 09/22/2016 6:41:30 PM PDT by YogicCowboy ("I am not entirely on anyone's side, because no one is entirely on mine." - JRRT)
[ Post Reply | Private Reply | To 1 | View Replies]

To: fortes fortuna juvat

I didn’t post it in breaking news, but now that you mention it...

And dark matter, I thought, was a working explanation in today’s physics, which is why this upsets the apple cart.


26 posted on 09/22/2016 6:54:13 PM PDT by sparklite2 (The game overs whether you play it or not.)
[ Post Reply | Private Reply | To 24 | View Replies]

To: YogicCowboy

Me, too. It’s cool to see we may have been right to be skeptical all along.


27 posted on 09/22/2016 6:55:29 PM PDT by sparklite2 (The game overs whether you play it or not.)
[ Post Reply | Private Reply | To 25 | View Replies]

To: sparklite2

I wouldn’t celebrate yet (I have no idea why non-experts hate the theory of dark matter).

https://medium.com/starts-with-a-bang/five-reasons-we-think-dark-matter-exists-a122bd606ba8


28 posted on 09/22/2016 7:02:49 PM PDT by Moonman62 (Make America Great Again!)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Moonman62

Great article. Thanks for posting. The article posted by the OP seems to challenge the second of 5 reasons.... interesting development.


29 posted on 09/22/2016 7:22:07 PM PDT by mwilli20 (BO. Making communists proud all over the world.)
[ Post Reply | Private Reply | To 28 | View Replies]

To: MUDDOG

If their calculations are right, then the presence of dark matter is not required to explain the internal motion of galaxies. This says nothing about the way they move wrt each other. It just weakens the argument for dark matter a bit.

But see below the article posted by moonman62. It seems that previously dark matter was well accepted as contributing to galaxy rotation so the jury is still out. This is just one result. It needs to be confirmed.


30 posted on 09/22/2016 7:27:38 PM PDT by mwilli20 (BO. Making communists proud all over the world.)
[ Post Reply | Private Reply | To 16 | View Replies]

To: mwilli20

That’s my take as well. The result enables ordinary matter to explain intragalactic motion, but not intergalactic motion and other big-scale phenomena.

If, as the article indicates, the current dark matter model is intimately tied up with intragalactic motion, that would seem to rule it out for everything else as well.


31 posted on 09/22/2016 7:45:14 PM PDT by MUDDOG
[ Post Reply | Private Reply | To 30 | View Replies]

To: babygene

Think I’ll to turn that into a School House Rock song.


32 posted on 09/22/2016 8:47:29 PM PDT by Eddie01 (Democrats are the Liquidate America Party)
[ Post Reply | Private Reply | To 7 | View Replies]

To: sparklite2

Wow. Really interesting.


33 posted on 09/22/2016 11:24:17 PM PDT by Eurotwit (The next president will either be an offensive, divisive, bigot with a bad haircut or Donald Trump)
[ Post Reply | Private Reply | To 1 | View Replies]


Navigation: use the links below to view more comments.
first previous 1-2021-33 last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
General/Chat
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson