tag:blogger.com,1999:blog-8429570072441023296.post1872914939277605327..comments2023-09-07T06:36:59.520-04:00Comments on The Virtual Philosophy Club: Contradictory Models ContinuedIra Glicksteinhttp://www.blogger.com/profile/10800080810596424897noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-8429570072441023296.post-83359162213163151832010-12-21T10:33:42.978-05:002010-12-21T10:33:42.978-05:00Sorry guys, but I'm uncomfortable with your ap...Sorry guys, but I'm uncomfortable with your approach. I believe quantum theory and its effectiveness. I just think it's used in this case like a sledge hammer to kill a fly. If all it's going to accomplish is to add some randomness to the collision process, I'd just as well put some imperfections on the containing wall. Random errors don't change the basic philosophical problem of decreasing entropy and the boundary between impossibility and improbability. I think that the answer lies in the "principle of equipartition of energy." The conflict between the idea of perfectly reflecting insulating walls and the tendency of energy to spread from macroscopic levels to microscopic levels seems to me to be at the root of the reversibility problem.joelhttps://www.blogger.com/profile/08770806025343971171noreply@blogger.comtag:blogger.com,1999:blog-8429570072441023296.post-83605322704003859672010-12-17T12:24:34.856-05:002010-12-17T12:24:34.856-05:00It's not just chaos. Heisenberg’s Uncertainty ...It's not just chaos. Heisenberg’s Uncertainty Principle is at the foundation of quantum theory. There is no possibility of escaping it without undermining the entire structure of modern physics. Einstein never questioned it. It applies to all objects observable by their position and momentum. Billiard balls are obviously included. <br /><br />Max Born in 1959 showed that after only a dozen classical (deterministic) collisions this inexorable uncertainty of the position and momentum of just the first ball has grown so large that all future trajectories are unpredictable. That is, you can’t be sure it will even hit another single ball. All you can do is give some statistics given a distribution of balls.<br /><br />HowardHoward Patteehttps://www.blogger.com/profile/12181204289094297715noreply@blogger.comtag:blogger.com,1999:blog-8429570072441023296.post-59534056999880349002010-12-16T21:35:54.001-05:002010-12-16T21:35:54.001-05:00Joel - Sorry for posting my "Einstein" t...Joel - Sorry for posting my "Einstein" topic on the same day as your new topic, but I promised the Philo Club here in The Villages that my Powerpoint charts for tomorrow's talk would be up in advance.<br /><br />On your points about reversibility, I look forward to Howard's reply. However, I was thinking similar thoughts about perfectly elastic and non-friction balls and walls and came to the same conclusions as Joel.<br /><br />Say you have a perfectly elastic ball on a friction-free table with perfectly elastic walls. <br /><br />Take a ball and place it anywhere you want and hit it with any force and at any angle you want. Call these the Initial (I) conditions and record them exactly. <br /><br />The ball will bounce from wall to wall to wall to wall forever unless you stop it. <br /><br />So, after a few bounces, measure the exact velocity (speed and angle) and rotation of the ball when it is at any point of its path. Call these the End (E) conditions.<br /><br />OK, stop the ball and place it at that exact location E. Now strike it such that it has the exact opposite velocity and rotation (-E) and, if all is friction-free and elastic, it will retrace its exact path and bounces and, eventually return to location I with the exactly opposite (-I) velocity and rotation. QED!<br /><br />Anticipating Howard's reply, and recalling our extensive and long ago discussions of chaos theory, I believe he will say that (since his world is continuous, unlike mine that is discrete :^) no matter how hard you try, you cannot get the EXACT Initial conditions nor the EXACT End conditions. Even if you could, you cannot strike the ball with the EXACT -E conditions, nor, when it returns to the I location, measure its EXACT -I conditions.<br /><br />Indeed, Howard may say, if you let the ball bounce more than X times (ten or twenty or some number related to your capability of exactitude), chaos theory takes over and its path is almost totally random. In other words, if you try to reproduce I or -E conditions, you will get a very different velocity and location after X bounces.<br /><br />How about that Howard, am I (still) a good student?<br /><br />Ira GlicksteinIra Glicksteinhttps://www.blogger.com/profile/10800080810596424897noreply@blogger.com