Two photons are traveling parallel to one another. Can the photons orbit one another perpendicular to the direction of travel? That is can the photons follow a stable long spiral path in flat space-time. The photons have no rest mass but they are not at rest. If they are traveling ( almost ) parallel paths they would be outside each others light cone and therefore no gravitational information can be transferred from one photon to another. Gravity however is directed toward where an object is and experiences no time delay, it also escapes a black hole so it seems to have properties which may escape a light cone.