[austintorn@aol.com]

“… whole new ball game.”

I just happened to be reading about DSR lately.

As you probably know, GLAST, launching in early 2008, has the sensitivity to probe the Planck scale by detecting a change of speed between protons with different energies in a gamma ray burst traveling over billions of years. One-thousandths of a second in arrival time could be noted.

In DSR, the 2nd special is that the Planck length would be universal for all observers, not involving any length contraction (as light speed is universal) and so all would agreed on the length.

DSR II claims that photons that have more energy travel faster, as in the early universe when temperature was very high.

The DSRs preserve but deepen special relativity; however, if special relativity were shown to break down at the quantum gravity scale, then there would be an absolute distinction between motion and rest.

For DSR, there is also the problem that the Planck energy was the bound for any body to have (leading to the ‘soccer ball problem’), but it is proposed, perhaps proved, that a body has a maximum energy that is one Planck energy for each proton it contains.