Einstein's special relativity beyond the speed of light

We propose here two new transformations between inertial frames that apply for relative velocities greater than the speed of light, and that are complementary to the Lorentz transformation, giving rise to the Einstein special theory of relativity that applies to relative velocities less than the speed of light. The new transformations arise from the same mathematical framework as the Lorentz transformation, displaying singular behaviour when the relative velocity approaches the speed of light and generating the same addition law for velocities, but, most importantly, do not involve the need to introduce imaginary masses or complicated physics to provide well-defined expressions. Making use of the dependence on relative velocity of the Lorentz transformation, the paper provides an elementary derivation of the new transformations between inertial frames for relative velocities v in excess of the speed of light c, and further we suggest two possible criteria from which one might infer one set of transformations as physically more likely than the other. If the energy–momentum equations are to be invariant under the new transformations, then the mass and energy are given, respectively, by the formulae and where denotes the limiting momentum for infinite relative velocity. If, however, the requirement of invariance is removed, then we may propose new mass and energy equations, and an example having finite non-zero mass in the limit of infinite relative velocity is given. In this highly controversial topic, our particular purpose is not to enter into the merits of existing theories, but rather to present a succinct and carefully reasoned account of a new aspect of Einstein's theory of special relativity, which properly allows for faster than light motion.

"We are mathematicians, not physicists, so we've approached this problem from a theoretical mathematical perspective," said Dr Cox. "Should it, however, be proven that motion faster than light is possible, then that would be game changing.
"Our paper doesn't try and explain how this could be achieved, just how equations of motion might operate in such regimes."

If, however, the requirement of invariance is removed, then we may propose new mass and energy equations, and an example having finite non-zero mass in the limit of infinite relative velocity is given. In this highly controversial topic, our particular purpose is not to enter into the merits of existing theories, but rather to present a succinct and carefully reasoned account of a new aspect of Einstein's theory of special relativity, which properly allows for faster than light motion.

Here is a recent note that points out what Cox and Hill did wrong:

Andréka, 'A note on "Einstein's special relativity beyond the speed of light" by James M. Hill and Barry J. Cox,' http://arxiv.org/abs/1211.2246

The criticism is essentially the same as in this thread and the physics.SE thread: the idea only works in n+n dimensions, not 3+1.

But Andréka, like Cox and Hill, doesn't seem to realize that this was all settled way back in 1986 by Recami.

Obviously the RSPA doesn't have very high standards or very knowledgeable reviewers if they accept this kind of paper, which is both wrong and wrong for reasons that have been known and published in the literature for 25 years.