51 research outputs found
Hestenes' Tetrad and Spin Connections
Defining a spin connection is necessary for formulating Dirac's bispinor
equation in a curved space-time. Hestenes has shown that a bispinor field is
equivalent to an orthonormal tetrad of vector fields together with a complex
scalar field. In this paper, we show that using Hestenes' tetrad for the spin
connection in a Riemannian space-time leads to a Yang-Mills formulation of the
Dirac Lagrangian in which the bispinor field is mapped to a set of Yang-Mills
gauge potentials and a complex scalar field. This result was previously proved
for a Minkowski space-time using Fierz identities. As an application we derive
several different non-Riemannian spin connections found in the literature
directly from an arbitrary linear connection acting on Hestenes' tetrad and
scalar fields. We also derive spin connections for which Dirac's bispinor
equation is form invariant. Previous work has not considered form invariance of
the Dirac equation as a criterion for defining a general spin connection
How Politics Shape Views Toward Fact-Checking: Evidence from Six European Countries
This is the author accepted manuscript. The final version is available from SAGE Publications via the DOI in this recordFact-checking has spread internationally, in part to confront the rise of digital disinformation
campaigns. American studies suggests ideological asymmetry in attitudes towards factchecking,
as well as greater acceptance of the practice among those more interested in and
knowledgeable about politics. We examine attitudes toward fact-checking across 6 European
counties to put these findings in a broader context (N = 6,067). We find greater familiarity with
and acceptance of fact-checking in Northern Europe (Sweden, Germany) than elsewhere (Italy,
Spain, France, Poland). We further find two dimensions of political antipathy: a left-right dimension
and an “anti-elite” dimension (including dissatisfaction with democracy and negative
feelings toward the E.U.), the latter of which more consistently predicts negative feelings toward
fact-checkers in the countries examined. Our findings demonstrate that despite general
acceptance of the movement, significant political divides remain. Those less likely to trust factcheckers
could be more vulnerable to disinformation targeting these divides, leading to a spiral
of cynicism.European Commissio
Non-uniqueness of the Dirac theory in a curved spacetime
We summarize a recent work on the subject title. The Dirac equation in a
curved spacetime depends on a field of coefficients (essentially the Dirac
matrices), for which a continuum of different choices are possible. We study
the conditions under which a change of the coefficient fields leads to an
equivalent Hamiltonian operator H, or to an equivalent energy operator E. In
this paper, we focus on the standard version of the gravitational Dirac
equation, but the non-uniqueness applies also to our alternative versions. We
find that the changes which lead to an equivalent operator H, or respectively
to an equivalent operator E, are determined by initial data, or respectively
have to make some point-dependent antihermitian matrix vanish. Thus, the vast
majority of the possible coefficient changes lead neither to an equivalent
operator H, nor to an equivalent operator E, whence a lack of uniqueness. We
show that even the Dirac energy spectrum is not unique.Comment: 13 pages (standard 12pt article format). Text of a talk given at the
1st Mediterranean Conference on Classical and Quantum Gravity, Kolymbari
(Greece), Sept. 14-18, 200
COVIDiSTRESS diverse dataset on psychological and behavioural outcomes one year into the COVID-19 pandemic
During the onset of the COVID-19 pandemic, the COVIDiSTRESS Consortium launched an open-access global survey to understand and improve individuals’ experiences related to the crisis. A year later, we extended this line of research by launching a new survey to address the dynamic landscape of the pandemic. This survey was released with the goal of addressing diversity, equity, and inclusion by working with over 150 researchers across the globe who collected data in 48 languages and dialects across 137 countries. The resulting cleaned dataset described here includes 15,740 of over 20,000 responses. The dataset allows cross-cultural study of psychological wellbeing and behaviours a year into the pandemic. It includes measures of stress, resilience, vaccine attitudes, trust in government and scientists, compliance, and information acquisition and misperceptions regarding COVID-19. Open-access raw and cleaned datasets with computed scores are available. Just as our initial COVIDiSTRESS dataset has facilitated government policy decisions regarding health crises, this dataset can be used by researchers and policy makers to inform research, decisions, and policy. © 2022, The Author(s).U.S. Department of Education, ED: P031S190304; Texas A and M International University, TAMIU; National Research University Higher School of Economics, ВШЭThe COVIDiSTRESS Consortium would like to acknowledge the contributions of friends and collaborators in translating and sharing the COVIDiSTRESS survey, as well as the study participants. Data analysis was supported by Texas A&M International University (TAMIU) Research Grant, TAMIU Act on Ideas, and the TAMIU Advancing Research and Curriculum Initiative (TAMIU ARC) awarded by the US Department of Education Developing Hispanic-Serving Institutions Program (Award # P031S190304). Data collection by Dmitrii Dubrov was supported within the framework of the Basic Research Program at HSE University, RF
Public perceptions and misperceptions of political authority in the European Union
This is the author accepted manuscript.How do citizens understand political authority within multi-level systems? We use original survey data from six European Union member states to assess the roles of political identity and interest in shaping citizen attitudes towards political authority in the European Union. We find that citizens with a greater interest in politics are more likely to express views on the authority of the European Union. These individuals are less likely to be uninformed. Interest does not necessarily mean that individuals hold correct perceptions. A substantive amount of voters are misinformed about the power of Brussels. We find that citizens with an exclusively national identity are more likely to hold misperceptions than those who think of themselves as both members of their nation and as Europeans.European Union Horizon 202
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