The current competition regime that characterizes international science is often presented as a quest for excellence. It diversely affects research in Latin America and research in the Organization ...for Economic Co-operation and Development (OECD) countries. This article asks how this competition regime may orient the direction of research in Latin America, and to whose advantage. It is argued that, by relating excellence to quality differently, a research policy that seeks to improve the level of science in Latin America while preserving the possibility of solving problems relevant to the region can be designed. Competition, it is also argued, certainly has its place in science, but not as a general management tool, especially if the goal is to improve overall quality of science in Latin America. Scientific competition is largely managed through journals and their reputation. Therefore, designing a science policy for Latin America (and for any ‘peripheral’ region of the world) requires paying special attention to the mechanisms underpinning the production, circulation and consumption of scientific journals. So-called ‘international’ or ‘core’ journals are of particular interest as local, national, or even regional journals must struggle to find their place in this peculiar publishing eco-system.
This paper provides elements in support of the random zero-point radiation field (zpf) as an essential ontological ingredient needed to explain distinctive properties of quantum-mechanical systems. ...We show that when an otherwise classical particle is connected to the zpf, a drastic, qualitative change in the dynamics takes place, leading eventually to the quantum dynamics. In particular, we demonstrate that in parallel with the evolution of the canonical variables of the particle into quantum operators satisfying the basic commutator x^,p^=iℏ, also the field canonical variables are transformed, giving rise to the corresponding creation and annihilation operators a^†,a^, satisfying a^,a^†=1. This allows for an explanation of quantum features such as quantum fluctuations, stationary states and transitions, and establishes a natural contact with (nonrelativistic) quantum electrodynamics.
The electron spin correlation is shown to be expressible in terms of a bona fide probability distribution function with an associated geometric representation. With this aim, an analysis is presented ...of the probabilistic features of the spin correlation within the quantum formalism, which helps clarify the concepts of contextuality and measurement dependence. The dependence of the spin correlation on
probabilities allows for a clear separation between system state and measurement context; the latter determines how the probability space should be partitioned in calculating the correlation. A probability distribution function ρ(ϕ) is then proposed, which reproduces the quantum correlation for a pair of single-particle spin projections and is amenable to a simple geometric representation that gives meaning to the variable ϕ. The same procedure is shown to be applicable to the bipartite system in the singlet spin state. This endows the spin correlation with a clear probabilistic meaning and leaves the door open for a possible physical picture of the electron spin, as discussed at the end of the paper.
Spin is a fundamental and distinctive property of the electron, having far-reaching implications. Yet its purely formal treatment often blurs the physical content and meaning of the spin operator and ...associated observables. In this work we propose to advance in disclosing the meaning behind the formalism, by first recalling some basic facts about the one-particle spin operator. Consistently informed by and in line with the quantum formalism, we then proceed to analyse in detail the spin projection operator correlation function
C
Q
(
a
,
b
)
=
σ
^
·
a
σ
^
·
b
for the bipartite singlet state, and show it to be amenable to an unequivocal probabilistic reading. In particular, the calculation of
C
Q
(
a
,
b
)
entails a partitioning of the probability space, which is dependent on the directions
(
a
,
b
)
.
The derivation of the CHSH- or other Bell-type inequalities, on the other hand, does not consider such partitioning. This observation puts into question the applicability of Bell-type inequalities to the bipartite singlet spin state.
We revisit the nonrelativistic problem of a bound, charged particle subject to the random zero-point radiation field (
zpf
), with the purpose of revealing the mechanism that takes it from the ...initially classical description to the final quantum-mechanical one. The combined effect of the
zpf
and the radiation reaction force results, after a characteristic time lapse, in the loss of the initial conditions and the concomitant irreversible transition of the dynamics to a stationary regime controlled by the field. In this regime, the canonical variables
x
,
p
become expressed in terms of the dipolar response functions to a set of field modes. A proper ordering of the response coefficients leads to the matrix representation of quantum mechanics, as was proposed in the early days of the theory, and to the basic commutator
x
^
,
p
^
=
i
ħ
. Further, the connection with the corresponding Fokker–Planck equation valid in the Markov approximation, allows one to obtain the (nonrelativistic) radiative corrections of
qed
. These results reaffirm the essentially electrodynamic and stochastic nature of the quantum phenomenon, as proposed by stochastic electrodynamics.
A global survey of researchers was conducted to gather perceptions on the prevalence and impact of predatory academic journals and conferences. The survey was open and inclusive in nature, with 1872 ...researchers, from a wide array of geographic regions, disciplines and academic career stages, voluntarily participating. Both quantitative and qualitative data were collected and analysed. The survey revealed that over 80% (1537 of 1859) of respondents perceive predatory practices are already a serious problem or on the rise in their country of work, and risk infiltrating and undermining the research enterprise if left unchallenged. At least 24% (445 of 1872) of respondents admitted they had already published in a predatory journal, participated in a predatory conference, or did not know if they had. Over 87% of respondents who had published (174 of 199) or participated (60 of 64) indicated that a lack of awareness of predatory practices was the main reason. Those in lower‐middle and upper‐middle‐income countries were more likely to indicate they had engaged in these activities than those in high‐income ones, with some disciplines appearing to engage more than others. Individual impact was mixed: some indicated no impact while others noted a range of negative and detrimental feelings.
We offer a possible physical explanation for the origin of the electron spin and the related antisymmetry of the wave function for a two-electron system, in the framework of nonrelativistic quantum ...mechanics as provided by linear stochastic electrodynamics. A consideration of the separate coupling of the electron to circularly polarized modes of the random electromagnetic vacuum field, allows to disclose the spin angular momentum and the associated magnetic moment with a
g
-factor 2, and to establish the connection with the usual operator formalism. The spin operator turns out to be the generator of internal rotations, in the corresponding coordinate representation. In a bipartite system, the distinction between exchange of particle coordinates (which include the internal rotation angle) and exchange of states becomes crucial. Following the analysis of the respective symmetry properties, the electrons are shown to couple in antiphase to the same vacuum field modes. This finding, encoded in the antisymmetry of the wave function, provides a physical rationale for the Pauli principle. The extension of our results to a multipartite system is briefly discussed.
The connection is established between two theories that have developed independently with the aim to describe quantum mechanics as a stochastic process, namely stochastic quantum mechanics (sqm) and ...stochastic electrodynamics (sed). Important commonalities and complementarities between the two theories are identified, notwithstanding their dissimilar origins and approaches. Further, the dynamical equation of sqm is completed with the radiation terms that are an integral element in sed. The central problem of the transition to the quantum dynamics is addressed, pointing to the key role of diffusion in the emergence of quantization.
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