6,044 research outputs found
From Dirac semimetals to topological phases in three dimensions: a coupled wire construction
Weyl and Dirac (semi)metals in three dimensions have robust gapless
electronic band structures. Their massless single-body energy spectra are
protected by symmetries such as lattice translation, (screw) rotation and time
reversal. In this manuscript, we discuss many-body interactions in these
systems. We focus on strong interactions that preserve symmetries and are
outside the single-body mean-field regime. By mapping a Dirac (semi)metal to a
model based on a three dimensional array of coupled Dirac wires, we show (1)
the Dirac (semi)metal can acquire a many-body excitation energy gap without
breaking the relevant symmetries, and (2) interaction can enable an anomalous
Weyl (semi)metallic phase that is otherwise forbidden by symmetries in the
single-body setting and can only be present holographically on the boundary of
a four dimensional weak topological insulator. Both of these topological states
support fractional gapped (gapless) bulk (resp. boundary) quasiparticle
excitations.Comment: 29 pages, 19 figures. This version has an expanded 'Summary of
Results' and 'Conclusion and Discussion' section to make it more accessible
to a broader audienc
On the autonomy of the aesthetic: Witkin I versus Witkin II
On this occasion we celebrate and deliberate the publication twenty years ago of
Robert Witkin’s “The Aesthetic Imperative of a Rational-Technical Machinery.” It is
a striking and richly textured essay. Witkin weaves together ambitious abstract
thinking, which takes off from the tradition of critical social theory, with a finegrained sensibility closely attuned to the aesthetic dimension of everyday and
organizational life
Performative Revolution in Egypt
This book is available as open access through the Bloomsbury Open Access programme and is available on www.bloomsburycollections.com. Jeffrey C. Alexander examines what was new about Egypt's Spring revolution. Why was it so compelling to watch, and what made it so effective and does it have implications for democratic movements internationally. Using international news reports and translations of the social media pages that brought Egyptians flocking onto Tahrir Square, Alexander uncovers the narrative of a revolution that was scripted by its organizers, as both a moral statement and a media and digital statement. He sees it as a theatrical performance, designed to reveal to the key protagonists what a civil, egalitarian society might look like, by showing it in microcosm on the Square. Ultimately, he argues, it was the sight of the protestor's behaviour that swayed the army, and brought about regime change. From the author of the widely acclaimed 2010 book: The Performance of Politics: Obama's Victory and the Democratic Struggle for Power, this powerful intervention into the debate on the Arab Spring is a must-read for those curious about how social media are fundamentally changing global politics
Telecommunications 2000 Strategy, HR Practices & Performance
This report constitutes the first benchmarking survey of business and human resource practices among a nationally representative sample of workplaces in the broadly defined telecommunications industry that includes wireline, wireless, cable, and internet providers. It grows out of a multi-year study of organizational change in the industry, and is based on extensive field study, site visits, interviews, and surveys conducted by research teams at Cornell and Rutgers Universities. Managers at 577 establishments across the country gave generously of their time during a lengthy telephone survey. The study was made possible through a generous grant by the Alfred P. Sloan Foundation.
While this report is based on data collected among workplaces in the U.S., it has implications for the restructuring of the global telecommunications industry. In other research, we have found that the United States has been at the forefront of market deregulation and technology change, but many other countries have followed a similar path and look to the United States as a model for organizational restructuring (Katz 1997). Thus, at least some of the patterns we find here are likely to occur in other countries undergoing similar patterns of deregulation
Telecommunications 2004: Business Strategy, HR Practices, and Performance
This national benchmarking report of the U.S. telecommunications services industry traces the tumultuous changes in management and workforce practices and performance in the sector over the last 5 years. This is a follow-up report to our 1998 study. At that time, when the industry was booming, we conducted a national survey of establishments in the industry. In 2003, we returned to do a second national survey of the industry, this time in a sector that was recovering from one of the worst recessions in its history
Trauma cultural, moralidad y solidaridad La construcción social del Holocausto y otros asesinatos en masa1
ResumenUn trauma cultural se produce cuando los miembros de una colectividad sienten que han sido sometidos a un acontecimiento horrendo que deja marcas indelebles sobre su conciencia colectiva, marcando sus memorias para siempre y cambiando su identidad futura de manera fundamental e irrevocable. Si bien este concepto científico sugiere relaciones empírico/causales entre sucesos, estructuras, percepciones y acciones previamente no relacionadas entre sí, también ilumina, de nueva cuenta, un dominio significativo de responsabilidad moral y acción política. Mediante la elaboración de traumas culturales, los grupos sociales, las sociedades nacionales, y a veces incluso civilizaciones enteras, no solo identifican cognitivamente la existencia y las fuentes del sufrimiento humano, sino que también pueden asumir cierta responsabilidad moral por ello. En la medida en que los grupos identifican las causas del trauma y asumen esa responsabilidad moral, los miembros de las colectividades definen sus relaciones solidarias para que les permitan, e incluso obliguen, a compartir el sufrimiento de los demás. ¿Es el sufrimiento de los otros también el nuestro? Al pensar que así podría ser, las sociedades amplían el círculo del “nosotros” y crean la posibilidad de que la reparación de las sociedades evite que el trauma vuelva a suceder. Empíricamente, este artículo considera la elaboración del trauma en el caso del Holocausto –el asesinato en masa de los judíos por los nazis así como su lugar fundacional en la elaboración del trauma y su resignificación–, y refiere a las experiencias de los afroamericanos, los indígenas, las víctimas coloniales del imperialismo Occidental y japonés, la Masacre Nanking y las víctimas de los regímenes comunistas de la Unión Soviética y de la china maoísta.AbstractA cultural trauma is produced when the members of a community feel they have gone through a dreadful event that has left indelible scars on their collective consciousness, branding forever their memories and changing their future identity in an essential and irrevocable way. Although this scientific concept suggests there are empiric/causal links among occurrences, structures, perceptions, and actions that were not previously connected, it also illuminates anew a significant domain of moral responsibility and political action. By elaborating cultural traumas, social groups, national societies and sometimes even entire civilizations may not only cognitively identify the existence and sources of human suffering, but also take certain moral responsibility for it. As groups identify the roots of trauma and assume a moral responsibility, the members of communities establish supportive relationships that may allow them –and even force them– to partake of the suffering of the others. Is the others’ suffering also our suffering? Insofar as it is deemed plausible, societies broaden the circle of the “us” and will endeavor to prevent the trauma from happening again by means of their healing process. This article considers empirically the working-through of a trauma in the case of the Holocaust –the massive extermination of Jews by the Nazis and its foundational status in the elaboration and re/signifying of the trauma–, and discusses the experiences of the Afro-Americans, the indigenous peoples, the colonial victims of Western and Japanese imperialism, the Nanking Massacre, and the victims of communist regimes of the Soviet Union and the Maoist China
Topological phase states of the SU(3) QCD
We consider the topologically nontrivial phase states and the corresponding
topological defects in the SU(3) d-dimensional quantum chromodynamics (QCD).
The homotopy groups for topological classes of such defects are calculated
explicitly. We have shown that the three nontrivial groups are pi_3 SU(3)=Z,
pi_5 SU(3)=Z, and pi_6 SU(3)=Z_6 if 3 < d < 6. The latter result means that we
are dealing exactly with six topologically different phase states. The
topological invariants for d=3,5,6 are described in detail.Comment: LATEX2e, 5 page
Performative Revolution in Egypt
This book is available as open access through the Bloomsbury Open Access programme and is available on www.bloomsburycollections.com. Jeffrey C. Alexander examines what was new about Egypt's Spring revolution. Why was it so compelling to watch, and what made it so effective and does it have implications for democratic movements internationally. Using international news reports and translations of the social media pages that brought Egyptians flocking onto Tahrir Square, Alexander uncovers the narrative of a revolution that was scripted by its organizers, as both a moral statement and a media and digital statement. He sees it as a theatrical performance, designed to reveal to the key protagonists what a civil, egalitarian society might look like, by showing it in microcosm on the Square. Ultimately, he argues, it was the sight of the protestor's behaviour that swayed the army, and brought about regime change. From the author of the widely acclaimed 2010 book: The Performance of Politics: Obama's Victory and the Democratic Struggle for Power, this powerful intervention into the debate on the Arab Spring is a must-read for those curious about how social media are fundamentally changing global politics
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