21. Where is chosen to be a unit vector which specifies the polarization of the field mode. 22. An orthonormal basis for Minkowski space necessarily consists of one timelike and three spacelike unit vectors . 23. Where \ mathbf { \ hat a } denotes the unit vector in the direction of. 24. Every countable orthonormal basis is equivalent to the standard unit vector basis in ! 2. 25. Where is the identity matrix and is a unit vector representing the reaction path tangent at. 26. A " normalised " eutactic star is a projected cross composed of unit vectors . 27. In the odd-dimensional case, is one-dimensional, spanned by a unit vector . 28. Then, we must orthogonalize the set of eigenvectors, and normalize each to become unit vectors . 29. When differentiating or integrating in cylindrical coordinates, these unit vectors themselves must also be operated on. 30. However, the unit vector basis is not boundedly complete in " c " 0.
