3,965 research outputs found

### Quantum Structures: An Attempt to Explain the Origin of their Appearance in Nature

We explain the quantum structure as due to the presence of two effects, (a) a
real change of state of the entity under influence of the measurement and, (b)
a lack of knowledge about a deeper deterministic reality of the measurement
process. We present a quantum machine, where we can illustrate in a simple way
how the quantum structure arises as a consequence of the two mentioned effects.
We introduce a parameter epsilon that measures the size of the lack of
knowledge on the measurement process, and by varying this parameter, we
describe a continuous evolution from a quantum structure (maximal lack of
knowledge) to a classical structure (zero lack of knowledge). We show that for
intermediate values of epsilon we find a new type of structure, that is neither
quantum nor classical. We apply the model that we have introduced to situations
of lack of knowledge about the measurement process appearing in other regions
of reality. More specifically we investigate the quantum-like structures that
appear in the situation of psychological decision processes, where the subject
is influenced during the testing, and forms some of his opinions during the
testing process. Our conclusion is that in the light of this explanation, the
quantum probabilities are epistemic and not ontological, which means that
quantum mechanics is compatible with a determinism of the whole.Comment: 22 pages, 8 figure

### Interpreting Quantum Particles as Conceptual Entities

We elaborate an interpretation of quantum physics founded on the hypothesis
that quantum particles are conceptual entities playing the role of
communication vehicles between material entities composed of ordinary matter
which function as memory structures for these quantum particles. We show in
which way this new interpretation gives rise to a natural explanation for the
quantum effects of interference and entanglement by analyzing how interference
and entanglement emerge for the case of human concepts. We put forward a scheme
to derive a metric based on similarity as a predecessor for the structure of
'space, time, momentum, energy' and 'quantum particles interacting with
ordinary matter' underlying standard quantum physics, within the new
interpretation, and making use of aspects of traditional quantum axiomatics.
More specifically, we analyze how the effect of non-locality arises as a
consequence of the confrontation of such an emerging metric type of structure
and the remaining presence of the basic conceptual structure on the fundamental
level, with the potential of being revealed in specific situations.Comment: 19 pages, 1 figur

### Using simple elastic bands to explain quantum mechanics: a conceptual review of two of Aert's machine-models

From the beginning of his research, the Belgian physicist Diederik Aerts has
shown great creativity in inventing a number of concrete machine-models that
have played an important role in the development of general mathematical and
conceptual formalisms for the description of the physical reality. These models
can also be used to demystify much of the strangeness in the behavior of
quantum entities, by allowing to have a peek at what's going on - in structural
terms - behind the "quantum scenes," during a measurement. In this author's
view, the importance of these machine-models, and of the approaches they have
originated, have been so far seriously underappreciated by the physics
community, despite their success in clarifying many challenges of quantum
physics. To fill this gap, and encourage a greater number of researchers to
take cognizance of the important work of so-called Geneva-Brussels school, we
describe and analyze in this paper two of Aerts' historical machine-models,
whose operations are based on simple breakable elastic bands. The first one,
called the spin quantum-machine, is able to replicate the quantum probabilities
associated with the spin measurement of a spin-1/2 entity. The second one,
called the \emph{connected vessels of water model} (of which we shall present
here an alternative version based on elastics) is able to violate Bell's
inequality, as coincidence measurements on entangled states can do.Comment: 15 pages, 5 figure

### Ephemeral properties and the illusion of microscopic particles

Founding our analysis on the Geneva-Brussels approach to quantum mechanics,
we use conventional macroscopic objects as guiding examples to clarify the
content of two important results of the beginning of twentieth century:
Einstein-Podolsky-Rosen's reality criterion and Heisenberg's uncertainty
principle. We then use them in combination to show that our widespread belief
in the existence of microscopic particles is only the result of a cognitive
illusion, as microscopic particles are not particles, but are instead the
ephemeral spatial and local manifestations of non-spatial and non-local
entities

### 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

### Quantum Machine and SR Approach: a Unified Model

The Geneva-Brussels approach to quantum mechanics (QM) and the semantic
realism (SR) nonstandard interpretation of QM exhibit some common features and
some deep conceptual differences. We discuss in this paper two elementary
models provided in the two approaches as intuitive supports to general
reasonings and as a proof of consistency of general assumptions, and show that
Aerts' quantum machine can be embodied into a macroscopic version of the
microscopic SR model, overcoming the seeming incompatibility between the two
models. This result provides some hints for the construction of a unified
perspective in which the two approaches can be properly placed.Comment: 21 pages, 5 figures. Introduction and Conclusions improved, minor
corrections in several sections. Accepted for publication in Foundations of
Physic

### 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

### Estimating stellar oscillation-related parameters and their uncertainties with the moment method

The moment method is a well known mode identification technique in
asteroseismology (where `mode' is to be understood in an astronomical rather
than in a statistical sense), which uses a time series of the first 3 moments
of a spectral line to estimate the discrete oscillation mode parameters l and
m. The method, contrary to many other mode identification techniques, also
provides estimates of other important continuous parameters such as the
inclination angle alpha, and the rotational velocity v_e. We developed a
statistical formalism for the moment method based on so-called generalized
estimating equations (GEE). This formalism allows the estimation of the
uncertainty of the continuous parameters taking into account that the different
moments of a line profile are correlated and that the uncertainty of the
observed moments also depends on the model parameters. Furthermore, we set up a
procedure to take into account the mode uncertainty, i.e., the fact that often
several modes (l,m) can adequately describe the data. We also introduce a new
lack of fit function which works at least as well as a previous discriminant
function, and which in addition allows us to identify the sign of the azimuthal
order m. We applied our method to the star HD181558, using several numerical
methods, from which we learned that numerically solving the estimating
equations is an intensive task. We report on the numerical results, from which
we gain insight in the statistical uncertainties of the physical parameters
involved in the moment method.Comment: The electronic online version from the publisher can be found at
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1467-9876.2005.00487.

### Multiperiodicity in the large-amplitude rapidly-rotating $\beta$Ceph ei star HD 203664

We perform a seismic study of the young massive $\beta$Cephei star HD 203664
with the goal to constrain its interior structure. Our study is based on a time
series of 328 new Geneva 7-colour photometric data of the star spread over
496.8 days. The data confirm the frequency of the dominant mode of the star
which we refine to $f_1=6.02885$c d$^{-1}$. The mode has a large amplitude of
37 mmag in V and is unambiguously identified as a dipole mode ($\ell=2$) from
its amplitude ratios and non-adiabatic computations. Besides $f_1$, we discover
two additional new frequencies in the star with amplitudes above $4\sigma$:
$f_2=6.82902$c d$^{-1}$ and $f_3=4.81543$c d$^{-1}$ or one of their daily
aliases. The amplitudes of these two modes are only between 3 and 4 mmag which
explains why they were not detected before. Their amplitude ratios are too
uncertain for mode identification. We show that the observed oscillation
spectrum of HD 203664 is compatible with standard stellar models but that we
have insufficient information for asteroseismic inferences. Among the
large-amplitude $\beta$Cephei stars, HD 203664 stands out as the only one
rotating at a significant fraction of its critical rotation velocity ($\sim
40%$).Comment: 7 pages, 5 figures, accepted for publication in A&A (Astronomy &
Astrophysics

### Estimating Stellar Parameters from Spectra using a Hierarchical Bayesian Approach

A method is developed for fitting theoretically predicted astronomical
spectra to an observed spectrum. Using a hierarchical Bayesian principle, the
method takes both systematic and statistical measurement errors into account,
which has not been done before in the astronomical literature. The goal is to
estimate fundamental stellar parameters and their associated uncertainties. The
non-availability of a convenient deterministic relation between stellar
parameters and the observed spectrum, combined with the computational
complexities this entails, necessitate the curtailment of the continuous
Bayesian model to a reduced model based on a grid of synthetic spectra. A
criterion for model selection based on the so-called predictive squared error
loss function is proposed, together with a measure for the goodness-of-fit
between observed and synthetic spectra. The proposed method is applied to the
infrared 2.38--2.60 \mic ISO-SWS data (Infrared Space Observatory - Short
Wavelength Spectrometer) of the star $\alpha$ Bootis, yielding estimates for
the stellar parameters: effective temperature \Teff = 4230 $\pm$ 83 K, gravity
$\log$ g = 1.50 $\pm$ 0.15 dex, and metallicity [Fe/H] = $-0.30 \pm 0.21$ dex.Comment: 15 pages, 8 figures, 5 tables. Accepted for publication in MNRA

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