Effective Theory Construction

I would agree with the charge that the classification scheme set forth in the remainder of this section is arbitrary. On the other hand, my hope was to try to find those points of commonality between the different ideas that have been set forth in the modeling of materials, and this classification reflects my own take on these common features. 

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The reason that the issue of locality assumptions has arisen in the context of effective theory construction is that such locality assumptions are one of the key tools taken up in the attempt to characterize the energetics of heterogeneous systems. It is amusing to note that interest in these systems arises precisely because they are not locally heterogeneous and yet, much of the theoretical machinery used to examine them is based on our understanding of homogeneous systems. The examples set forth above are just a few of the different ways in which locality assumptions have been invoked over the course of this book. 

Of course, the idea of effective theory construction is not a new one at this late stage in the book. Indeed, much of what we have described in this book has surrounded the business of constructing effective theories. Our use of the word effective in this context is not intended to conjure up images of such ideas as especially competent. Rather, we speak of theories which have shed their reductionist cloak and whose aim it is to account for observable nature on the... 

Throughout the course of this book we have flown the flag of degree of freedom reduction and effective theory construction. One of the first places we described such thinking was in section 4.2.2 where we invoked the transcription... 

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