2,017 research outputs found
Literature, planning and infrastructure: Investigating the southern city through postcolonial texts
This article explores the ways in which postcolonial literary and other cultural texts navigate, decode and in some cases re-imagine the infrastructures that organize urban life, particularly in the postcolonial cities of Johannesburg, London and Delhi. Readings of Ivan VladislaviÄ, Mark Gevisser Brian Chikwava, Selma Dabbagh, Rana Dasgupta and Manju Kapur consider the constantly shifting relationship between urban planning, the organization of public space, and various other forms of human intervention, and suggest that the ways in which urban spaces are mapped in creative practice can explore, negotiate and at times disrupt and reconstruct that relationship
The 21st century propulsion
The prediction of future space travel in the next millennium starts by examining the past and extrapolating into the far future. Goals for the 21st century include expanded space travel and establishment of permanent manned outposts, and representation of Lunar and Mars outposts as the most immediate future in space. Nuclear stage design/program considerations; launch considerations for manned Mars missions; and far future propulsion schemes are outlined
Competing mechanisms of chiral symmetry breaking in a generalized Gross-Neveu model
Chiral symmetry of the 2-dimensional chiral Gross-Neveu model is broken
explicitly by a bare mass term as well as a splitting of scalar and
pseudo-scalar coupling constants. The vacuum and light hadrons - mesons and
baryons which become massless in the chiral limit - are explored analytically
in leading order of the derivative expansion by means of a double sine-Gordon
equation. Depending on the parameters, this model features new phenomena as
compared to previously investigated 4-fermion models: spontaneous breaking of
parity, a non-trivial chiral vacuum angle, twisted kink-like baryons whose
baryon number reflects the vacuum angle, crystals with alternating baryons, and
appearance of a false vacuum.Comment: 8 pages, 7 figures; v2: typos correcte
Is dark matter an extra-dimensional effect?
We investigate the possibility that the observed behavior of test particles
outside galaxies, which is usually explained by assuming the presence of dark
matter, is the result of the dynamical evolution of particles in higher
dimensional space-times. Hence, dark matter may be a direct consequence of the
presence of an extra force, generated by the presence of extra-dimensions,
which modifies the dynamic law of motion, but does not change the intrinsic
properties of the particles, like, for example, the mass (inertia). We discuss
in some detail several possible particular forms for the extra force, and the
acceleration law of the particles is derived. Therefore, the constancy of the
galactic rotation curves may be considered as an empirical evidence for the
existence of the extra dimensions.Comment: 11 pages, no figures, accepted for publication in MPLA; references
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Very special relativity as relativity of dark matter: the Elko connection
In the very special relativity (VSR) proposal by Cohen and Glashow, it was
pointed out that invariance under HOM(2) is both necessary and sufficient to
explain the null result of the Michelson-Morely experiment. It is the quantum
field theoretic demand of locality, or the requirement of P, T, CP, or CT
invariance, that makes invariance under the Lorentz group a necessity.
Originally it was conjectured that VSR operates at the Planck scale; we propose
that the natural arena for VSR is at energies similar to the standard model,
but in the dark sector. To this end we provide an ab initio spinor
representation invariant under the SIM(2) avatar of VSR and construct a mass
dimension one fermionic quantum field of spin one half. This field turns out to
be a very close sibling of Elko and it exhibits the same striking property of
intrinsic darkness with respect to the standard model fields. In the new
construct, the tension between Elko and Lorentz symmetries is fully resolved.
We thus entertain the possibility that the symmetries underlying the standard
model matter and gauge fields are those of Lorentz, while the event space
underlying the dark matter and the dark gauge fields supports the algebraic
structure underlying VSR.Comment: 19 pages. Section 5 is new. Published version (modulo a footnote, and
a corrected typo
Recommended from our members
Introduction: The City Always Wins
This book brings the insights of social geographers and cultural historians into a critical dialogue with literary narratives of urban culture and theories of literary cultural production
Recommended from our members
Planned Violence: Post/Colonial Urban Infrastructure, Literature, and Culture
In this Introduction, the collectionās editors offer critical readings of Omar Robert Hamiltonās debut novel, The City Always Wins (2017), alongside a number of other literary texts, to open up and explicate the bookās orienting concept of āPlanned Violenceā. It situates the book in recent interdisciplinary work on infrastructures as both physical and aesthetic objects, and in commentaries on the relationship between the spatial layouts of post/colonial cities and the different kinds of violence to which they give rise. Throughout it further emphasizes the resistant quality of literary and cultural production as a way to diagnose and counter the planned violence of urban infrastructures in the post/colonial city, which is one of the collectionās overarching efforts. It concludes with a summary overview of the bookās three sections, highlighting the relationships between the chapters and creative interludes that follow
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