1/15/11  Impossiblasaurs

      Paleontologists tell us about towering beasts that once roamed the Earth, dinosaurs. Natural history museums prominently display the skeletal remains of the great creatures assembled like Tinker-toy sculptures. Hollywood has dramatically portrayed the ferocious monsters in numerous blockbusters. There's only one problem, by our current understanding of biology and physics dinosaurs are impossible.

      Muscle strength is proportional to size. A muscle two times the diameter of another will be four times as strong. But weight increases even more, a muscle twice the diameter will weigh eight times as much. This relationship limits the size of any animal. Calculations indicate the heaviest elephants of today approach this strength to weight limit.

      The largest dinosaurs were many times as big as an elephant. An animal that size wouldn't even have the muscle strength to stand, let alone walk around. Yet large numbers of unearthed dinosaurs bones show they must have existed. The numerous footprints they left behind showed they walked around on land. On top of that there were elephant-size dinosaurs that flew. Imagine the lift needed for that. What gives?

      One can imagine two possibilities. Dinosaurs had super strong muscles, or dinosaurs were super lightweight. My guess as to the biological plausibility of super strong muscles would be just that, a guess. Still, one wonders how different such muscles would be, how much energy can you get out of a calorie and how many calories super strong muscles burn.

      The other possible answer, super lightweight dinosaurs, suggests a simpler solution, Earth's gravity was less in the past. Consider this, an elephant on the lower gravity moon would be just as strong but very much lighter. It could grow much bigger before reaching the strength to weight limit. In other words, grow as big as a dinosaur. And be light enough to fly, too.

      Physicists say gravity is a constant. But have they proven it? They certainly know what gravity does, but not what exactly it is, how it works. So how do they know it is unchanging?

      In any event, something must account for dinosaurs which couldn't exist today by our current understanding. Ponder one more thing, what if an increase in gravity is what caused dinosaurs to go extinct?

12/8/11  The Incredible Shrinking Man

      This is purely in the realm of fantasy, but what would it mean if a person shrunk down to an inch tall? In the movie "The Incredible Shrinking Man" we get an idea, only the wrong idea.

      In the film the tiny man wants to get down from a table so he rigs a rope, which is string, and climbs down. Thing is, he could have simply jumped down with no problem. Even though he's really small, the table is still only 30 inches from the floor. The acceleration over a particular distance will be the same regardless of the man's size. If a full-size man can safely jump down from a table, so can a tiny man.

      In fact, a tiny man would be able to jump down more safely than a full-size man. The tiny man has a great deal less mass and so the impact at the same speed will be less. The tiny man is so light and lands with so little force he might be able to jump off the roof safely.

      Here's a personal anecdote to back this up. One day sitting on my back stoop I saw a squirrel fall out of a tree from maybe 20 feet up. It landed with a thump, got up, and ran away back up the tree. A squirrel is so light it doesn't hit with as much impact as a man would falling 20 feet out of a tree. It also helps the squirrel has a higher strength to weight ratio, which is explained next.

      Perhaps you've heard about how incredibly strong an ant is because it can lift 10 times its own weight. That is not so incredible, its a matter of its being small. Muscles grow heavier with size at a higher rate than they grow stronger with size. Meaning the bigger and stronger an animal gets the less it can lift relative to its weight.

      The reverse is also true, the smaller it gets the more it can lift relative to its weight. The ant is not incredibly strong, its incredibly small and thus its strength to weight ratio is high. As it would be for any tiny creature, including a tiny man. A full-size man might weigh 200 pounds and it would be an effort to lift his own weight above his head. The tiny man might weigh a pound, but would have little problem lifting twice his weight above his head. Even so, he's only lifting two pounds.

      The tiny man would also move like a hectic little mouse with very quick steps. When a full-size man takes a step his foot will move about two feet. It takes time to move his foot that distance at a given acceleration. On the other hand the tiny man's step is maybe a half inch. It would take very little time to move his foot that distance at the same acceleration. It's like a long and short pendulum. In one second the long pendulum makes one stroke, the short pendulum two strokes. Yet they both cover the same distance.

      The tiny man could jump up higher relative to his height as well. A house cat can jump several times its height, maybe five or six feet high. A lion would have to jump 15 to 20 feet up to do the same. It can't. It's too big and the distance is too far. It's akin to the pendulums, a matter of acceleration of mass over distance. Distance is not relative, 20 feet is 20 feet no matter how big or small you are.

      The tiny man's voice and hearing would change, too. But I wouldn't worry about that. I wouldn't worry about any of this because it's pretty unlikely to ever happen.