Every once in a while I imagine myself sitting under a large tree teaching youth about the world around them. Socrates-like. I don’t know why.<\/p>\n
The last little lesson that popped into my head was about motion. I had kicked a small stone, which had skittered along the pavement for a bit, hopped over the curb, and eventually nestled in the leaves of the un-mowed grass.<\/p>\n
And I thought: So, kids, is the stone still moving?<\/p>\n
Of course, there are lots of different ways to answer this question.<\/p>\n
Internal Motion<\/strong><\/p>\n Imagine a mass of little worms on the ground, surrounded and contained by a metal ring. The mass as a whole isn’t moving in relation to the ground, but the worms are squirming and wriggling.<\/p>\n Point at the ring of worms and ask whether it’s moving. A lot of people would say, “yes. And it’s disgusting.”<\/p>\n Of course, the molecules of the rock are moving as well, and within the molecules, the atoms and subatomic particles are all moving like crazy. So there’s plenty of motion going on.<\/p>\n Motion in relation to… just about everything<\/strong><\/p>\n The rock isn’t moving in relation to the earth. It sits there. But we all know that the earth is revolving. And while it revolves, it goes around the sun. And the sun, along with our whole arm of our galaxy, is moving around the center of the galaxy. And the galaxy is moving away from every other galaxy in the universe.<\/p>\n So in fact, the rock is moving in very complicated ways. From an observer on another galaxy, or even on our own sun, it’s whirling and careening in a crazy pattern.<\/p>\n In fact, from any vantage point in the whole universe, other than earth, the stone is practically alive with motion.<\/p>\n In my mind, I make the stone glow very brightly, then I make everything else in the universe fade away so that I only see the stone. No earth or sun or galaxy to get in the way. I position myself somewhere, truly motionless, and watch that glowy thing fly around. Magnificent.<\/p>\n [What is “truly” motionless? Can we say? Motion is always judged as being relative to something else, isn’t it? What if nothing else is there? Or is there an objective “fabric” of the universe that’s always there to move against? That’s for the next lesson under the next tree. We’ll have to wait awhile for that one, since no one really knows the answers.]<\/p>\n","protected":false},"excerpt":{"rendered":" Every once in a while I imagine myself sitting under a large tree teaching youth about the world around them. Socrates-like. I don’t know why. The last little lesson that popped into my head was about motion. I had kicked a small stone, which had skittered along the pavement for a bit, hopped over the […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-432","post","type-post","status-publish","format-standard","hentry","category-science-and-such"],"_links":{"self":[{"href":"https:\/\/weeklyrob.com\/index.php?rest_route=\/wp\/v2\/posts\/432","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/weeklyrob.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/weeklyrob.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/weeklyrob.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/weeklyrob.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=432"}],"version-history":[{"count":0,"href":"https:\/\/weeklyrob.com\/index.php?rest_route=\/wp\/v2\/posts\/432\/revisions"}],"wp:attachment":[{"href":"https:\/\/weeklyrob.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=432"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/weeklyrob.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=432"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/weeklyrob.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=432"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}