Thanks for the clarification. I didn&#x27;t mean to imply that LQG researchers had no interest in proving their framework to be compatible with Yang-Mills theory: that&#x27;s obviously an essential test of any realistic theory of gravity! My intent was to share my impression that they generally weren&#x27;t expecting Yang-Mills to appear &quot;automatically&quot; as a necessary component of the LQG formalism (much less for a specific group structure and matter content to be required by it). That&#x27;s in contrast to string theory, which <i>does</i> seem to fairly inevitably generate not just quantum gravity but also gauge theory by one mechanism or another. (And for a while, many or most string theorists were optimistic that a unique preferred background would turn up within a few years, too.)<p>I guess I&#x27;d say that string theorists I&#x27;ve known just don&#x27;t think about LQG folks much. I&#x27;ve seen skepticism and some level of hostility, too, when there was an LQG talk in the department. But even then it usually came with a baseline level of professional respect. (Maybe I wouldn&#x27;t say that so readily if I&#x27;d ever met Lubos Motl. There are always a <i>few</i> trolls, right?)<p>As you point out, quite a few LQG proponents talk about string theory rather a lot, and some even publish articles in which LQG proponent characters argue circles around straw man string theorist caricatures. (I read this one when it came out, as I recall. It made some good points, but it didn&#x27;t go out of its way to portray the string theorist character as a decent human being, and the tone overall was just so damned <i>smug</i>.)