Mathematical Principles of Theoretical Physics

(Rick Simeone) #1

4.6. WEAK INTERACTION THEORY 241


Hence, we deduce from (4.6.35) and (4.6.36) that

81


(


ρw
ρn

) 6


g^2 w=

8



2


(


mw
mp

) 2


× 10 −^5 ̄hc.

Then we derive the relation

(4.6.37) g^2 w=

8


81



2


(


mw
mp

) 2


× 10 −^5 ×


(


ρn
ρw

) 6


̄hc.

In a comparison with (4.5.66) and (4.6.37), we find that the strong chargegsand the weak
chargegwhave the same magnitude order. Direct computation shows that

g^2 w
g^2 s

≃ 0. 35 equivalently

gw
gs

≃ 0. 6.


4.6.4 PID mechanism of spontaneous symmetry breaking


In the derivation of equations (4.6.7) and (4.6.8) we have used the PID mechanism of sponta-
neous symmetry breaking. In this subsection we shall discuss the intermediate vector bosons
W±,Zand their dual scalar bosonsH±,H^0 , called the Higgs particles by using the PID mech-
anism of spontaneous symmetry breaking.
We know that the interaction field equations are oriented toward two directions: i) to
derive interaction forces, and ii) to describe the field particles and derive the particle transition
probability. The PID-PRI weak interaction field equations describing field particles are given
by (4.4.42)-(4.4.45). Here, for convenience, we write them again as follows:


∂νWν μa −

gw
̄hc

εbcagα βWα μbWβc−gwJμa= (∂μ−

1


4


(mHc
̄h

) 2


xμ+

gw
̄hc

(4.6.38) γbWμb)φa,

−∂μ∂μφa+

(m
Hc
h ̄

) 2


φa−
gw
̄hc

(4.6.39) γb∂μ(Wμbφa)

=


gw
̄hc

εbcagα β∂μ(Wα μbWβc)+gw∂μJaμ−

1


4


(


mHc
h ̄

)^2 xμ∂μφa,

wheremHis the Higgs particle mass, andWμa( 1 ≤a≤ 3 )describe the intermediate vector
bosons as follows

(4.6.40)


W±: Wμ^1 ±iWμ^2 ,
Z: Wμ^3 ,

andφadescribe the dual Higgs bosons as

(4.6.41)


H±: φ^1 ±iφ^2 ,
H^0 : φ^3.

By (4.4.46), equations (4.6.38)-(4.6.39) need to be supplemented with three gauge fixing
equations. According to physical requirement, we take these equations as

(4.6.42) ∂μWμa= 0 for 1≤a≤ 3.
Free download pdf