Equation Icon  ( ) ( ) δĖ™= − (1 + w ) šœƒ − 3Ė™Φ − 3 Ė™a- δp-− wδ for ν = 0 (1.3.17 ) a ¯ρ aĖ™ wĖ™ δpāˆ•¯ρ šœƒĖ™= − --(1 − 3w )šœƒ − ------šœƒ + k2------+ k2Ψ − k2 π for ν = i. (1.3.18 ) a 1 + w 1 + w