tag:blogger.com,1999:blog-34480619.post4507598146853423918..comments2024-03-11T13:47:03.621-05:00Comments on Physics and Physicists: A Prediction Falsified but Ignored?ZapperZhttp://www.blogger.com/profile/15861398273820851809noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-34480619.post-76746013290369945242007-04-30T20:54:00.000-05:002007-04-30T20:54:00.000-05:00Dear ZapperZ,The paper of Arkani-Hamed didn't pred...Dear ZapperZ,<BR/><BR/>The paper of Arkani-Hamed didn't predict a particular number of extra dimensions. It said that -if- the number of extra dimensions is 2 (if I remember the number correctly), then their size would be a fraction of a millimeter. However, he doesn't claim that the number -must- be 2. The possibility of more than 2 extra dimensions (which implies that their size is smaller) hasn't been falsified in the experiments you mention.<BR/><BR/>Another thing to note, is that the theory is a -suggestion- for physics beyond the Standard Model. It can't be derived just from the physics we know. This is just one out of many possibilities. Even Arkani-Hamed himself suggested other completely different alternative scenarios. All these theories are consistent with what we know and satisfy basic mathematical consistency with principles that are believed to be true (e.g., Lorentz invariance, quantum mechanics). Only experiment can tell which of the possibilities (if any) was chosen by Nature. (Alternatively, string theory might be able to tell us the whole story one day.)Anonymousnoreply@blogger.com