Two dimensional modeling of collisionless shocks has been of tremendous importance in understanding the physics of the non-linear evolution , momentum transfer and particle acceleration , but current computer capacities have now reached a point where three dimensional modeling is becoming feasible .
We present the first three dimensional model of a fully developed and relaxed relativistic ion-electron shock , and analyze and compare it to similar 2D models .
Quantitative and qualitative differences are found with respect to the two-dimensional models .
The shock jump conditions are of course different , because of the extra degree of freedom , but in addition it is found that strong parallel electric fields develop at the shock interface , the level of magnetic field energy is lower , and the non-thermal particle distribution is shallower with a powerlaw index of \sim 2.2 .