Re: Thanks Dale, logically convinced one minute, then...
Posted by Dale on Mar 07, 2002 at 11:05
Re: Thanks Dale, logically convinced one minute, then... (dogrock)Thanks for the clear example, must have taken some effort.
Yes, it takes effort but I think it is worth it. Especially when I can make it clear. :)
To ask if the change is “real” depends on what the word “real” means. It is real in terms that a stationary observer can assume it is occurring and predict results of experiments undertaken with the moving objects and get the right results. But, if you mean by real that the object undergoes a physical change, then no, it isn’t real because the moving object can not detect that it is moving by looking at any of its physical properties.
Everything is relative. For example, we can look at the background radiation of the universe which is a result of the big bang and see it is different in different directions. From this we can deduce that we are moving at a very high speed with respect to the center of the universe. (a href= http://antwrp.gsfc.nasa.gov/apod/ap990627.html> http://antwrp.gsfc.nasa.gov/apod/ap990627.html) Someone at the center of the universe would see us as being heavy, slow, and out of shape. But you don’t see the difference when you rotate a ruler back and forth 90 degrees to a line from you to the center of the universe. So, the question is, are the changes a “real” stationary observer sees in your ruler really real? The stationary observer sees that your radioactive elements spitting out particles that travel farther in a direction tangent to our expansion than in the direction of the expansion but you don't because you can't see your ruler changing. Which is the illusion and which is real?