5,489 research outputs found
The Guppy Effect as Interference
People use conjunctions and disjunctions of concepts in ways that violate the
rules of classical logic, such as the law of compositionality. Specifically,
they overextend conjunctions of concepts, a phenomenon referred to as the Guppy
Effect. We build on previous efforts to develop a quantum model that explains
the Guppy Effect in terms of interference. Using a well-studied data set with
16 exemplars that exhibit the Guppy Effect, we developed a 17-dimensional
complex Hilbert space H that models the data and demonstrates the relationship
between overextension and interference. We view the interference effect as, not
a logical fallacy on the conjunction, but a signal that out of the two
constituent concepts, a new concept has emerged.Comment: 10 page
Can we observe fuzzballs or firewalls?
In the fuzzball paradigm the information paradox is resolved because the
black hole is replaced by an object with no horizon. One may therefore ask if
observations can distinguish a traditional hole from a fuzzball. We find: (a)
It is very difficult to reflect quanta off the surface of a fuzzball, mainly
because geodesics starting near the horizon radius cannot escape to infinity
unless their starting direction is very close to radial. (b) If infalling
particles interact with the emerging radiation before they are engulfed by the
horizon, then we say that we have a `firewall behavior'. We consider several
types of interactions, but find no evidence for firewall behavior in any theory
that obeys causality. (c) Photons with wavelengths {\it larger} than the black
hole radius can be scattered off the emerging radiation, but a very small
fraction of the backscattered photons will be able to escape back to infinity.Comment: 52 pages, 4 figure
Experimental Evidence for Quantum Structure in Cognition
We proof a theorem that shows that a collection of experimental data of
membership weights of items with respect to a pair of concepts and its
conjunction cannot be modeled within a classical measure theoretic weight
structure in case the experimental data contain the effect called
overextension. Since the effect of overextension, analogue to the well-known
guppy effect for concept combinations, is abundant in all experiments testing
weights of items with respect to pairs of concepts and their conjunctions, our
theorem constitutes a no-go theorem for classical measure structure for common
data of membership weights of items with respect to concepts and their
combinations. We put forward a simple geometric criterion that reveals the non
classicality of the membership weight structure and use experimentally measured
membership weights estimated by subjects in experiments to illustrate our
geometrical criterion. The violation of the classical weight structure is
similar to the violation of the well-known Bell inequalities studied in quantum
mechanics, and hence suggests that the quantum formalism and hence the modeling
by quantum membership weights can accomplish what classical membership weights
cannot do.Comment: 12 pages, 3 figure
Meaning-focused and Quantum-inspired Information Retrieval
In recent years, quantum-based methods have promisingly integrated the
traditional procedures in information retrieval (IR) and natural language
processing (NLP). Inspired by our research on the identification and
application of quantum structures in cognition, more specifically our work on
the representation of concepts and their combinations, we put forward a
'quantum meaning based' framework for structured query retrieval in text
corpora and standardized testing corpora. This scheme for IR rests on
considering as basic notions, (i) 'entities of meaning', e.g., concepts and
their combinations and (ii) traces of such entities of meaning, which is how
documents are considered in this approach. The meaning content of these
'entities of meaning' is reconstructed by solving an 'inverse problem' in the
quantum formalism, consisting of reconstructing the full states of the entities
of meaning from their collapsed states identified as traces in relevant
documents. The advantages with respect to traditional approaches, such as
Latent Semantic Analysis (LSA), are discussed by means of concrete examples.Comment: 11 page
Full action of two deformation operators in the D1D5 CFT
We are interested in thermalization in the D1D5 CFT, since this process is
expected to be dual to black hole formation. We expect that the lowest order
process where thermalization occurs will be at second order in the perturbation
that moves us away from the orbifold point. The operator governing the
deformation off of the orbifold point consists of a twist operator combined
with a supercharge operator acting on this twist. In a previous paper we
computed the action of two twist operators on an arbitrary state of the CFT. In
the present work we compute the action of the supercharges on these twist
operators, thereby obtaining the full action of two deformation operators on an
arbitrary state of the CFT. We show that the full amplitude can be related to
the amplitude with just the twists through an action of the supercharge
operators on the initial and final states. The essential part of this
computation consists of moving the contours from the twist operators to the
initial and final states; to do this one must first map the amplitude to a
covering space where the twists are removed, and then map back to the original
space on which the CFT is defined.Comment: 48 pages, 2 figure
Lifting of D1-D5-P states
We consider states of the D1-D5 CFT where only the left-moving sector is
excited. As we deform away from the orbifold point, some of these states will
remain BPS while others can `lift'. We compute this lifting for a particular
family of D1-D5-P states, at second order in the deformation off the orbifold
point. We note that the maximally twisted sector of the CFT is special: the
covering surface appearing in the correlator can only be genus one while for
other sectors there is always a genus zero contribution. We use the results to
argue that fuzzball configurations should be studied for the full class
including both extremal and near-extremal states; many extremal configurations
may be best seen as special limits of near extremal configurations.Comment: 51 pages, 6 figure
Modeling Concept Combinations in a Quantum-theoretic Framework
We present modeling for conceptual combinations which uses the mathematical
formalism of quantum theory. Our model faithfully describes a large amount of
experimental data collected by different scholars on concept conjunctions and
disjunctions. Furthermore, our approach sheds a new light on long standing
drawbacks connected with vagueness, or fuzziness, of concepts, and puts forward
a completely novel possible solution to the 'combination problem' in concept
theory. Additionally, we introduce an explanation for the occurrence of quantum
structures in the mechanisms and dynamics of concepts and, more generally, in
cognitive and decision processes, according to which human thought is a well
structured superposition of a 'logical thought' and a 'conceptual thought', and
the latter usually prevails over the former, at variance with some widespread
beliefsComment: 5 pages. arXiv admin note: substantial text overlap with
arXiv:1311.605
Chandra observations of the HII complex G5.89-0.39 and TeV gamma-ray source HESSJ1800-240B
We present the results of our investigation, using a Chandra X-ray
observation, into the stellar population of the massive star formation region
G5.89-0.39, and its potential connection to the coincident TeV gamma-ray source
HESSJ1800-240B. G5.89-0.39 comprises two separate HII regions G5.89-0.39A and
G5.89-0.39B (an ultra-compact HII region). We identified 159 individual X-ray
point sources in our observation using the source detection algorithm
\texttt{wavdetect}. 35 X-ray sources are associated with the HII complex
G5.89-0.39. The 35 X-ray sources represent an average unabsorbed luminosity
(0.3-10\,keV) of \,erg/s, typical of B7-B5 type stars. The
potential ionising source of G5.89-0.39B known as Feldt's star is possibly
identified in our observation with an unabsorbed X-ray luminosity suggestive of
a B7-B5 star. The stacked energy spectra of these sources is well-fitted with a
single thermal plasma APEC model with kT5\,keV, and column density
N\,cm (A). The residual
(source-subtracted) X-ray emission towards G5.89-0.39A and B is about 30\% and
25\% larger than their respective stacked source luminosities. Assuming this
residual emission is from unresolved stellar sources, the total
B-type-equivalent stellar content in G5.89-0.39A and B would be 75 stars,
consistent with an earlier estimate of the total stellar mass of hot stars in
G5.89-0.39. We have also looked at the variability of the 35 X-ray sources in
G5.89-0.39. Ten of these sources are flagged as being variable. Further studies
are needed to determine the exact causes of the variability, however the
variability could point towards pre-main sequence stars. Such a stellar
population could provide sufficient kinetic energy to account for a part of the
GeV to TeV gamma-ray emission in the source HESSJ1800-240B.Comment: 34 pages, 9 figure
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