9,731 research outputs found
The Utopian
The paper was concerned with the future of the social housing complex in Poplar, East London called Robin Hood Gardens designed, conceived and built in the late 60's by Alison and Peter Smithson. The project and publication centred on the possible future for the building through a series of articles and conceptual visions created by us as the authors
Two-dimensional conformal field theory and the butterfly effect
We study chaotic dynamics in two-dimensional conformal field theory through
out-of-time order thermal correlators of the form .
We reproduce bulk calculations similar to those of [1], by studying the large
Virasoro identity block. The contribution of this block to the above
correlation function begins to decrease exponentially after a delay of , where is the scrambling
time , and are the energy scales of the
operators.Comment: v1: 14 pages plus appendices, 2 figures. v2: references updated and
minor changes to the text. v3: minor error corrected in Appendix B, but the
conclusion is unchange
Lieb-Robinson and the butterfly effect
As experiments are increasingly able to probe the quantum dynamics of systems
with many degrees of freedom, it is interesting to probe fundamental bounds on
the dynamics of quantum information. We elaborate on the relationship between
one such bound---the Lieb-Robinson bound---and the butterfly effect in
strongly-coupled quantum systems. The butterfly effect implies the ballistic
growth of local operators in time, which can be quantified with the "butterfly"
velocity . Similarly, the Lieb-Robinson velocity places a state
independent ballistic upper bound on the size of time evolved operators in
non-relativistic lattice models. Here, we argue that is a state-dependent
effective Lieb-Robinson velocity. We study the butterfly velocity in a wide
variety of quantum field theories using holography and compare with free
particle computations to understand the role of strong coupling. We find that,
depending on the way length and time scale, acquires a temperature
dependence and decreases towards the IR. We also comment on experimental
prospects and on the relationship between the butterfly velocity and signaling.Comment: 5+5 pages, 0 figures. v2: updated references and additional
clarification
A national survey of in-service staff activities and projects in business education.
Thesis (M.Ed.)--Boston Universit
Development of Cranberry Girdler, \u3ci\u3eChrysoteuchia Topiaria\u3c/i\u3e (Lepidoptera: Pyraliadae) in Relation to Temperature
The development of Chrysoteuchia topiaria was studied in controlled-temperature chambers. Estimates of the threshold temperatures for the egg, larval, and prepupal-pupal stages were 9.4,6.8, and 9.8°C, respectively. An overall threshold temperature for egg to adult development was estimated to be 8.8°C. Degree-day summations above thresholds averaged 107, 484, and 388 for the egg, larval, and prepupal-pupal stages, respectively
The goldstone and goldstino of supersymmetric inflation
We construct the minimal effective field theory (EFT) of supersymmetric
inflation, whose field content is a real scalar, the goldstone for
time-translation breaking, and a Weyl fermion, the goldstino for supersymmetry
(SUSY) breaking. The inflating background can be viewed as a single
SUSY-breaking sector, and the degrees of freedom can be efficiently
parameterized using constrained superfields. Our EFT is comprised of a chiral
superfield X_NL containing the goldstino and satisfying X_NL^2 = 0, and a real
superfield B_NL containing both the goldstino and the goldstone, satisfying
X_NL B_NL = B_NL^3 = 0. We match results from our EFT formalism to existing
results for SUSY broken by a fluid background, showing that the goldstino
propagates with subluminal velocities. The same effect can also be derived from
the unitary gauge gravitino action after embedding our EFT in supergravity. If
the gravitino mass is comparable to the Hubble scale during inflation, we
identify a new parameter in the EFT related to a time-dependent phase of the
gravitino mass parameter. We briefly comment on the leading contributions of
goldstino loops to inflationary observables.Comment: 32 pages, 2 figures. v3: clarifications and references added. Matches
JHEP version. v2: typos fixed, footnote and references adde
Localized shocks
We study products of precursors of spatially local operators,
, where .
Using chaotic spin-chain numerics and gauge/gravity duality, we show that a
single precursor fills a spatial region that grows linearly in . In a
lattice system, products of such operators can be represented using tensor
networks. In gauge/gravity duality, they are related to Einstein-Rosen bridges
supported by localized shock waves. We find a geometrical correspondence
between these two descriptions, generalizing earlier work in the spatially
homogeneous case.Comment: 23 pages plus appendices, 12 figures. v2: minor error in Appendix B
corrected. v3: figure added to the introduction comparing the butterfly
effect cone with the standard light con
Hawking-Page transition in holographic massive gravity
We study the Hawking-Page transition in a holographic model of field theories
with momentum dissipation. We find that the deconfinement temperature strictly
decreases as momentum dissipation is increased. For sufficiently strong
momentum dissipation, the critical temperature goes to zero, indicating a
zero-temperature deconfinement transition in the dual field theory.Comment: 17 pages, 1 figure, uncomment \newcommand*{\ShowCalculations}{} in
the tex file for additional details. Journal version (PRD). Presentation
clarified, reference added, and line spacing and title update
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