7.6. THEORY OF DARK MATTER AND DARK ENERGY 477
we obtain from (7.6.22) that
(7.6.24) 3 α 2 = 24 kπ α 1 +k+ 1.
By the relation (7.6.24) from (7.6.22), we can also derive, in the same fashion as above,
the dark energy formula (7.6.23).
7.6.3 PID gravitational interaction formula
Consider a central gravitational field generated by a ballBr 0 with radiusr 0 and massM. It is
known that the metric of the central field atr>r 0 can be written in the form
(7.6.25) ds^2 =−euc^2 dt^2 +evdr^2 +r^2 (dθ^2 +sin^2 θdφ^2 ),
andu=u(r),v=v(r).
In the exterior ofBr 0 , the energy-momentum is zero, i.e.
Tμ ν= 0 , forr>r 0.Hence, the PID gravitational field equation for the metric (7.6.25) is given by
(7.6.26) Rμ ν−
1
2
gμ νR=−∇μ νφ, r>r 0.whereφ=φ(r)is a scalar function ofr.
By (7.1.25) and (7.1.26), we have
R 00 −
1
2
g 00 R=−1
reu−v[
v′+1
r(ev− 1 )]
,
R 11 −
1
2
g 11 R=−1
r[
u′−1
r(ev− 1 )]
,
R 22 −
1
2
g 22 R=−r^2
2e−v[
u′′+(
1
2
u′+1
r)
(u′−v′)]
,
∇ 00 φ=−1
2
eu−vu′φ′,∇ 11 φ=φ′′−1
2
v′φ′,∇ 22 φ=−re−vφ′.Thus, the fields equations (7.6.26) are as follows(7.6.27)
v′+1
r(ev− 1 ) =−r
2u′φ′,u′−1
r(ev− 1 ) =r(φ′′−1
2
v′φ′),u′′+(
1
2
u′+1
r)
(u′−v′) =−2
rφ′.