Our experience of reality is fairly continuous. We see surfaces everywhere, and underneath those surfaces are solid or fluid volumes. It all seems like pretty connected stuff.<\/p>\n
But this all breaks down when things get either much bigger than us or much smaller than us. In a neat bit of symmetry, “bigger” and “smaller” in this case both mean about a factor of a billion.<\/p>\n
Once you get to the size of a typical star (like our sun), which is about a billion times bigger than we are, the Universe starts to look like a bunch of little specks with a whole lot of empty space between them. This pattern continues up to the largest “things” we know about, galactic superclusters, which are about 224<\/sup> times bigger than we are.<\/p>\n If you look in the other direction, pretty much the same thing happens. Everything seems fairly continuous until you get down to the level of small molecules, which are about a billion times smaller than we are.<\/p>\n Any smaller than that, and everything is little specks inside vast empty spaces, first at the level of atoms within molecules, then nucleii within atoms, and all the way on down to neutrinos, the smallest “things” we can measure, which are about 224<\/sup> times smaller than we are.**<\/sup><\/p>\n So in a sense we are in the middle of a kind of island. When you look at the entire span of scales in the known Universe, it’s mostly dust to dust, with just a little patch of land right in the middle. That little patch is where we are.<\/p>\n ** Strings in string theory can get about 100 billion times smaller than neutrinos, but we have no direct evidence that they exist, let alone any way to measure them.<\/small><\/p>\n","protected":false},"excerpt":{"rendered":" Our experience of reality is fairly continuous. We see surfaces everywhere, and underneath those surfaces are solid or fluid volumes. It all seems like pretty connected stuff. But this all breaks down when things get either much bigger than us or much smaller than us. In a neat bit of symmetry, “bigger” and “smaller” in … Continue reading “From dust to dust”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts\/14334"}],"collection":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=14334"}],"version-history":[{"count":4,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts\/14334\/revisions"}],"predecessor-version":[{"id":14338,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts\/14334\/revisions\/14338"}],"wp:attachment":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14334"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14334"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14334"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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