In Candidacy for the Degree of Doctor of Philosophy

, Ph.D. Dissertation Sharif University of Technology Afshar, Hamid Reza (Author) ; Arfaei, Hessamaddin (Supervisor) ; Grumiller, Daniel (Supervisor)

Abstract

In this thesis, we show that conformal Chern–Simons gravity in three dimensions has various holographic descriptions. They depend on the boundary conditions on the conformal equivalence class and the Weyl factor. The boundary conditions on the Weyl factor of the metric lead to three physically distinct scenarios: I. trivial Weyl factor, II. non-trivial but fixed Weyl factor and III. free Weyl factor. The metric is not necessarily asymptotically AdS in cases II and III, but nevertheless a dual CFT appears to emerge. We focus on a particular case III where an affine U(1) algebra related to holomorphic Weyl rescalings shifts one of the central charges by 1. The Weyl factor then behaves as a...

Conformal Chern-Simons holography

, Article Physical Review D - Particles, Fields, Gravitation and Cosmology ; Volume 85, Issue 6 , 2012 ; 15507998 (ISSN) Afshar, H ; Cvetkovic, B ; Ertl, S ; Grumiller, D ; Johansson, N ; Sharif University of Technology

2012

Abstract

We discuss a fine-tuning of rather generic 3-dimensional higher-curvature gravity actions that leads to gauge symmetry enhancement at the linearized level via partial masslessness. Requiring this gauge symmetry to be present also nonlinearly reduces such actions to conformal Chern-Simons gravity. We perform a canonical analysis of this theory and construct the gauge generators and associated charges. We provide and classify admissible boundary conditions. The boundary conditions on the conformal equivalence class of the metric render one chirality of the partially massless Weyl gravitons normalizable and the remaining one non-normalizable. There are three choices-trivial, fixed, or free-for...

Holograms of conformal Chern-Simons gravity

, Article Physical Review D - Particles, Fields, Gravitation and Cosmology ; Volume 84, Issue 4 , Jun , 2011 ; 15507998 (ISSN) Afshar, H ; Cvetković, B ; Ertl, S ; Grumiller, D ; Johansson, N ; Sharif University of Technology

2011

Abstract

We show that conformal Chern-Simons gravity in three dimensions has various holographic descriptions. They depend on the boundary conditions on the conformal equivalence class and the Weyl factor, even when the former is restricted to asymptotic anti-de Sitter behavior. For constant or fixed Weyl factor our results agree with a suitable scaling limit of topologically massive gravity results. For varying Weyl factor we find an enhancement of the asymptotic symmetry group, the details of which depend on certain choices. We focus on a particular example where an affine u^(1) algebra related to holomorphic Weyl rescalings shifts one of the central charges by 1. The Weyl factor then behaves as a...

Building energy modeling with OpenStudio : a practical guide for students

, Book Brackney, Larry ; Parker, Andrew ; Macumber, Daniel

Springer International Publishing AG 2018

Self‐assembled, nanowire network electrodes for depleted bulk heterojunction solar cells (Adv. Mater. 12/2013) [electronic resource]

, Article Journal of Advanced Materials ; March 2013, Vol. 25, Issue 12, PP. 1768 Lan, X. (Xinzheng) ; Bai, Jing ; Masala, Silvia ; Thon, Susanna M ; Ren, Yuan ; Kramer, Illan J ; Hoogland, Sjoerd ; Simchi, A. (Abdolreza) ; Koleilat, Ghada I ; Paz‐Soldan, Daniel ; Ning, Zhijun ; Labelle, André J ; Kim, Jin Young ; Jabbour, Ghassan ; Sargent, Edward H ; Sharif University of Technology

Abstract

A solution-processed, bottom-up nanowire network electrode is developed and employed in a bulk heterojunction colloidal quantum dot solar cell. The electrode features a ZnO template which is converted into locally connected, infi ltratable TiO2 nanowires. The new electrode allows the application of a thicker light absorbing fi lm without compromising the charge extraction, as reported by Edward H. Sargent, Ghassan Jabbour, and co-workers on page 1769. The frontispiece shows schematically the electrode shape and the resultant device architecture