<story><title>An ultra-precise clock shows how to link the quantum world with gravity</title><url>https://www.quantamagazine.org/an-atomic-clock-promises-link-between-quantum-world-and-gravity-20211025/</url></story><parent_chain></parent_chain><comment><author>lisper</author><text>Note that they are not actually measuring the gravitational influence of the atoms themselves.  They are measuring the difference in &lt;i&gt;earth&amp;#x27;s&lt;/i&gt; gravitational field at two locations separated by a millimeter.  That is a stupendous technological achievement, but it is not in and of itself progress towards a theory of quantum gravity.</text></comment>
<story><title>An ultra-precise clock shows how to link the quantum world with gravity</title><url>https://www.quantamagazine.org/an-atomic-clock-promises-link-between-quantum-world-and-gravity-20211025/</url></story><parent_chain></parent_chain><comment><author>ck2</author><text>I thought they already measured this via satellites and time dilation, GPS in particular has to know exactly how much time is lost&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Frame-dragging&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Frame-dragging&lt;/a&gt;&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Time_dilation&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Time_dilation&lt;/a&gt;</text></comment>