John Carlos Baez<p>This is the color of infinite hotness. </p><p>This is the color something gets in the limit where its temperature approaches infinity. Of course you’d instantly be fried by gamma rays of arbitrarily high frequency, but this would be its spectrum in the visible range.</p><p>This is also the color of a typical neutron star. They’re so hot they look the same!</p><p>It’s also the color of the very early Universe!</p><p>This was worked out by David Madore, and you can find the details at my blog article, including a discussion of whether this is exactly the right color:</p><p><a href="https://johncarlosbaez.wordpress.com/2022/01/16/the-color-of-infinite-temperature" target="_blank" rel="nofollow noopener noreferrer" translate="no"><span class="invisible">https://</span><span class="ellipsis">johncarlosbaez.wordpress.com/2</span><span class="invisible">022/01/16/the-color-of-infinite-temperature</span></a></p><p>Luckily, the alternative someone suggested is so close I can&#39;t tell the difference.</p><p>For computer screens and cell phones this color is approximately <a href="https://mathstodon.xyz/tags/98b5ff" class="mention hashtag" rel="tag">#<span>98b5ff</span></a>. </p><p>Perhaps we should call it &quot;baby blue&quot; - for the early universe.</p>