remove photon-like check

Framework/Geometry/FourVector.h

@@ -63,9 +63,11 @@ namespace corsika::geometry {
       return GetTimeSquared() > fSpaceLike.squaredNorm();
     } //! Norm2 > 0
 
+    /* this is not numerically stable
     bool IsPhotonlike() const {
       return GetTimeSquared() == fSpaceLike.squaredNorm();
     } //! Norm2 == 0
+    */
 
     FourVector& operator+=(const FourVector& b) {
       fTimeLike += b.fTimeLike;

Framework/Geometry/testFourVector.cc

@@ -63,15 +63,15 @@ TEST_CASE("four vectors") {
 
     CHECK(p0.IsSpacelike());
     CHECK(!p0.IsTimelike());
-    CHECK(!p0.IsPhotonlike());
+    //CHECK(!p0.IsPhotonlike());
 
     CHECK(!p1.IsSpacelike());
     CHECK(p1.IsTimelike());
-    CHECK(!p1.IsPhotonlike());
+    //CHECK(!p1.IsPhotonlike());
 
     CHECK(!p2.IsSpacelike());
     CHECK(!p2.IsTimelike());
-    CHECK(p2.IsPhotonlike());
+    //CHECK(p2.IsPhotonlike());
   }
 
   /*