<story><title>The possibilities for dark matter have shrunk</title><url>https://www.sciencenews.org/article/dark-matter-wimps-lz</url></story><parent_chain><item><author>mppm</author><text>By the way, apart from the fact that dark matter predictions have been contradicted by increasingly sensitive experiments over and over and over, there is another inconvenient piece of observational evidence: An analysis of stellar velocities at the edge of the Milky Way, published last year [1] shows that they are &amp;quot;Keplerian&amp;quot;, i.e. following classical behavior without the influence of any purported dark matter. So either the Milky Way is anomalously dark matter deficient (how very convenient :), or maybe the discrepancy that dark matter was invented to explain will simply disappear when more accurate astronomical data including the fainter stars becomes available.&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.scientificamerican.com&amp;#x2F;article&amp;#x2F;the-milky-way-may-be-missing-a-trillion-suns-worth-of-mass&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.scientificamerican.com&amp;#x2F;article&amp;#x2F;the-milky-way-may...&lt;/a&gt;</text></item></parent_chain><comment><author>SideQuark</author><text>That link also claims that the results you&amp;#x27;re listing are not likely to hold up, including comments from an author of the paper used for the article. So if one of the paper;s own authors expects these claims to disappear once more data is gathered, then maybe it&amp;#x27;s too early to claim the end of dark matter.&lt;p&gt;After all, DM has been measured in many different ways. One surprising finding doesn&amp;#x27;t negate hundreds of surprising findings without significantly more evidence.&lt;p&gt;&amp;gt; shows that they are &amp;quot;Keplerian&amp;quot;, i.e. following classical behavior without the influence of any purported dark matter.&lt;p&gt;That is NOT at all what the paper says [1]. if you actually read the paper, and don&amp;#x27;t interject your beliefs and reword it, in every instance they use the phrase &amp;quot;Keplerian decline,&amp;quot; which does not AT ALL mean classical, which would break relativity and be a massive surprise. The phrase &amp;quot;Keplerian decline&amp;quot; means the measured items are less than expected for the previous model. The movement, even with this decline, are far beyond what Kepler&amp;#x27;s laws would imply (and even Kepler&amp;#x27;s laws are demonstrably wrong in our solar system - see the precession of Mercury for example).&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.aanda.org&amp;#x2F;component&amp;#x2F;article?access=doi&amp;amp;doi=10.1051&amp;#x2F;0004-6361&amp;#x2F;202347513&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.aanda.org&amp;#x2F;component&amp;#x2F;article?access=doi&amp;amp;doi=10.10...&lt;/a&gt;</text></comment>
<story><title>The possibilities for dark matter have shrunk</title><url>https://www.sciencenews.org/article/dark-matter-wimps-lz</url></story><parent_chain><item><author>mppm</author><text>By the way, apart from the fact that dark matter predictions have been contradicted by increasingly sensitive experiments over and over and over, there is another inconvenient piece of observational evidence: An analysis of stellar velocities at the edge of the Milky Way, published last year [1] shows that they are &amp;quot;Keplerian&amp;quot;, i.e. following classical behavior without the influence of any purported dark matter. So either the Milky Way is anomalously dark matter deficient (how very convenient :), or maybe the discrepancy that dark matter was invented to explain will simply disappear when more accurate astronomical data including the fainter stars becomes available.&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.scientificamerican.com&amp;#x2F;article&amp;#x2F;the-milky-way-may-be-missing-a-trillion-suns-worth-of-mass&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.scientificamerican.com&amp;#x2F;article&amp;#x2F;the-milky-way-may...&lt;/a&gt;</text></item></parent_chain><comment><author>FactolSarin</author><text>We&amp;#x27;ve also seen instances where visible &amp;quot;clumping&amp;quot; in a galactic disc correspond to differences in the rotation curves, which dark matter can&amp;#x27;t really explain. But this is still a topic of much debate.&lt;p&gt;However, there&amp;#x27;s lots of good evidence for dark matter besides rotation curves of galaxies. For instance, models of galactic formation work a lot better with it than without it (without dark matter, as galaxies coalesce, they get hot and the pressure keeps the gas apart and makes star formation really hard).&lt;p&gt;We also see the Bullet Cluster, where two galaxies collided&amp;#x2F;passed through each other. The gas and dust has been slowed down from collisions, but the dark matter has passed right through. We know this from the gravitational lensing. The lensing happens around the mass of the galaxy, but with the bullet cluster, the lens is off to the side where there is no normal matter, because the dark matter kept going when the regular matter slowed down.&lt;p&gt;In other words, we have some really good evidence for dark matter, but there&amp;#x27;s a few things going on here and there we can&amp;#x27;t explain.</text></comment>