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  variation of the scalar field theory

+ 1 like - 0 dislike
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I am reading Polchinski's review on AdS/CFT https://arxiv.org/abs/1010.6134.
I have a very simple question, and please help me out. Thanks in advanced.

The question abou formula (3.19)
The scalarbulk effective  action is given by
S0,cl=12LD1dzdDxϕcl(m2)ϕcl+η2ϵ1DdDxϕclϵϕcl


The bdy action is
Sb=ηΔ2ϵDdDxϕ2(ϵ,x)

The variation of the whole action is given by
δ(S0,cl+Sb)=ηϵDdDxδϕcl(ϵϵΔ)ϕcl

My question is why there is no such term dDxϕclϵϵδϕcl in the variation of the action?

asked Jan 24, 2018 in Theoretical Physics by C Thone (110 points) [ revision history ]

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