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Taking the LEED? Analyzing spatial variations in market penetration rates of eco-labeled properties
This paper investigates the impact of policies to promote the adoption of LEED-certified buildings across CBSA in the United States. Drawing upon a unique database that combines data from a large number of sources and using a number of regression procedures, the determinants of the proportion LEED-certified space for more than 170 CBSA in the US is modeled. LEED-certified space still accounts for a relatively small proportion of commercial stock in all markets. The average proportion is less than 1%. There is no conclusive evidence of a positive impact of policy intervention on the levels of LEED-certified space. However, after accounting for bias introduced by non-random assignment of policies, we find preliminary evidence of a positive impact of city-level green building incentives. There is a significant positive association between market size and indicators of economic vitality on proportions of LEED-certified space
Integrated education, intergroup relations, and political identities in Northern Ireland
Published as Hayes, BC., McAllister, I. & Dowds, L. (2007). 'Integrated education, intergroup relations, and political identities in Northern Ireland.' Social Problems 54(4) pp. 454-482.© 2007 by Society for the Study of Social Problems, Inc. Copying and permissions notice: Authorization to copy this content beyond fair use (as specified in Sections 107 and 108 of the U. S. Copyright Law) for internal or personal use, or the internal or personal use of specific clients, is granted on behalf of the Society for the Study of Social Problems for libraries and other users, provided that they are registered with and pay the specified fee via Rightslink® on Caliber, http://caliber.ucpress.net/ or directly with the Copyright Clearance Center, http://www.copyright.com.Non peer reviewedPublisher PD
Planckian Axions in String Theory
We argue that super-Planckian diameters of axion fundamental domains can
naturally arise in Calabi-Yau compactifications of string theory. In a theory
with axions , the fundamental domain is a polytope defined by the
periodicities of the axions, via constraints of the form . We compute the diameter of the fundamental domain in terms of
the eigenvalues of the metric on field space, and also,
crucially, the largest eigenvalue of . At large ,
approaches a Wishart matrix, due to universality, and we show that
the diameter is at least , exceeding the naive Pythagorean range by a
factor . This result is robust in the presence of constraints,
while for the diameter is further enhanced by eigenvector delocalization
to . We directly verify our results in explicit Calabi-Yau
compactifications of type IIB string theory. In the classic example with
where parametrically controlled moduli stabilization was
demonstrated by Denef et al. in [1], the largest metric eigenvalue obeys . The random matrix analysis then predicts, and we
exhibit, axion diameters for the precise vacuum parameters found in
[1]. Our results provide a framework for achieving large-field axion inflation
in well-understood flux vacua.Comment: 42 pages, 4 figure
Chaotic inflation with kinetic alignment of axion fields
N-flation is a radiatively stable scenario for chaotic inflation in which the displacements of N≫1 axions with decay constants f1≤…≤fN<MP lead to a super-Planckian effective displacement equal to the Pythagorean sum fPy of the fi. We show that mixing in the axion kinetic term generically leads to the phenomenon of kinetic alignment, allowing for effective displacements as large as N−−√fN≥fPy, even if f1,…,fN−1 are arbitrarily small. At the level of kinematics, the necessary alignment occurs with very high probability, because of eigenvector delocalization. We present conditions under which inflation can take place along an aligned direction. Our construction sharply reduces the challenge of realizing N-flation in string theory
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