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Modern language models and vector-symbolic architectures show that vector-based models are capable of handling the compositional, structured, and symbolic properties required for human concepts. Vectors are also able to handle key phenomena from the psychology, including computation of features and similarities, reasoning about relations and analogies, and representation of theories. Language models show how vector representation of word semantics and sentences can interface between concepts and language, as seen in definitional theories of concepts or ad hoc concepts. The idea of Church encoding, from logic, allows us to understand how meaning can arise in vector-based or symbolic systems. By combining these recent computational results with classic findings in psychology, vector-based models provide a compelling account of human conceptual representation. For decades, cognitive scientists have debated what kind of representation might characterize human concepts. Whatever the format of the representation, it must allow for the computation of varied properties, including similarities, features, categories, definitions, and relations. It must also support the development of theories, ad hoc categories, and knowledge of procedures. Here, we discuss why vector-based representations provide a compelling account that can meet all these needs while being plausibly encoded into neural architectures. This view has become especially promising with recent advances in both large language models and vector symbolic architectures. These innovations show how vectors can handle many properties traditionally thought to be out of reach for neural models, including compositionality, definitions, structures, and symbolic computational processes. [ABSTRACT FROM AUTHOR]

We investigate a phenomenological equation of state for the gluon plasma, which differs from the ideal gluon gas equation of state in three aspects: (a) it is assumed that gluons with low momentum are subject to confining interactions and do not contribute to the energy spectrum of free gluons; (b) only gluons with high momentum are considered as an ideal gas with perturbative corrections of order O(α); (c) a non-perturbative vacuum pressure is included. We show that feature (a) allows for a reasonable perturbative treatment of the interaction between gluons with high momentum. The equation of state reproduces lattice data for the thermodynamical functions of the SU(3) pure gauge theory above the deconfinement transition temperature T. This result suggests that a possible way to describe the gluon plasma is in terms of perturbatively interacting gluons and non-perturbative 'glueball' states. [ABSTRACT FROM AUTHOR]

Recent data of the HADES Collaboration in Au+Au central collisions at s NN = 2.4 GeV indicate large proton number fluctuations inside one unit of rapidity around midrapidity. This can be a signature of critical phenomena due to the strong attractive interactions between baryons. We study an alternative hypothesis that these large fluctuations are caused by the event-by-event fluctuations of the number of bare protons, and no interactions between these protons are assumed. The proton number fluctuations in five symmetric rapidity intervals Δ y inside the region Δ Y = 1 are calculated using the binomial acceptance procedure. This procedure assumes the independent (uncorrelated) emission of protons, and it appears to be in agreement with the HADES data. To check this simple picture we suggest to calculate the correlation between proton multiplicities in non-overlapping rapidity intervals Δ y 1 and Δ y 2 placed inside Δ Y = 1. [ABSTRACT FROM AUTHOR]

Despite increased awareness of the lack of gender equity in academia and a growing number of initiatives to address issues of diversity, change is slow, and inequalities remain. A major source of inequity is gender bias, which has a substantial negative impact on the careers, work-life balance, and mental health of underrepresented groups in science. Here, we argue that gender bias is not a single problem but manifests as a collection of distinct issues that impact researchers' lives. We disentangle these facets and propose concrete solutions that can be adopted by individuals, academic institutions, and society. Despite increased awareness of the lack of gender equity in academia, change is slow, and inequalities remain. We disentangle the different aspects of gender bias impacting woman researchers throughout their lives. We expose the different issues and discuss potential solutions that can be adopted by individuals, academic institutions, and society. [ABSTRACT FROM AUTHOR]

We investigate the development of the directed, v 1 , and elliptic flow, v 2 , in heavy ion collisions in mid-central Au+Au reactions at E lab = 1.23 A GeV. We demonstrate that the elliptic flow of hot and dense matter is initially positive (v 2 > 0) due to the early pressure gradient. This positive v 2 transfers its momentum to the spectators, which leads to the creation of the directed flow v 1. In turn, the spectator shadowing of the in-plane expansion leads to a preferred decoupling of hadrons in the out-of-plane direction and results in a negative v 2 for the observable final state hadrons. We propose a measurement of v 1 − v 2 flow correlations and of the elliptic flow of dileptons as methods to pin down this evolution pattern. The elliptic flow of the dileptons allows then to determine the early-state EoS more precisely, because it avoids the strong modifications of the momentum distribution due to shadowing seen in the protons. This opens the unique opportunity for the HADES and CBM collaborations to measure the Equation-of-State directly at 2-3 times nuclear saturation density. [ABSTRACT FROM AUTHOR]

The nuclear liquid-gas transition at normal nuclear densities, n≈n0=0.16fm-3, and small temperatures, T≈20MeV, has a large influence on analytic properties of the QCD grand-canonical thermodynamic potential. A classical van der Waals equation is used to determine qualitatively these unexpected features due to dense cold matter. The existence of the nuclear matter critical point results in thermodynamic branch points, which are located at complex chemical potential values, for T>Tc≃20MeV, and exhibit a moderate model dependence up to rather large temperatures T≲100MeV. The behavior at higher temperatures is studied using the van der Waals hadron resonance gas (vdW-HRG) model. The baryon-baryon interactions have a decisive influence on the QCD thermodynamics close to μB=0. In particular, nuclear matter singularities limit the radius of convergence rμB/T of the Taylor expansion in μB/T, with rμB/T≈2-3 values at T≈140-170MeV obtained in the vdW-HRG model. [ABSTRACT FROM AUTHOR]