We test Kang’s (2024) central-body statistical-mechanics disk model against SPARC 3.6 μm profiles using the ordinary-differential-equation system defined by that paper’s Equation (28). Photometric errors enter every fit through a heteroscedastic likelihood, and every radial M/L curve is fitted independently. Of 136 galaxies, 135 retain usable profiles and 122 strongly favor a broken exponential over a single exponential. In the primary ODE28 variant, ODE28 is strongly preferred for 66 objects, inconclusive for 20, and disfavored for 34 of 120 finite fits. In 35 cases its likelihood is lower, confirming that BIC combines fit and complexity. Physical vetting leaves 18 usable cases and seven usable with caution; 41 statistical preferences are diagnostic-only because of non-positive or boundary-sensitive parameters, inactive central terms, or implausible scale relations. NGC3877 is the most stable Type II benchmark, while NGC5985 remains supported with caution. The fixed-M/L sensitivity tests retain strong support for 36 of the 66 constant-M/L preferences in all seven curves and for 57 in at least four; 14 of the other 56 profiles gain strong support for at least one curve. The results support Kang’s model as a restricted, falsifiable hypothesis for regular disk mass profiles, not as a universal replacement for broken exponentials.
We consider a quintessence scalar field with a class of hyperbolic potential. This potential effectively introduces matter-like components into the cosmological fluid, contributing to the dark sector of the universe. For the observational analysis, we employ the PantheonPlus and Union3.0 catalogues, Cosmic Chronometers, and Baryon Acoustic Oscillations from the DESI DR2 collaboration. We test the hypothesis that quintessence can unify the dark sector. Our results reveal that, although the quintessence field provides a minor contribution to the matter component, the data do not show any support for the unification scenario.
Based on the two postulates of the invariance of both the laws of physics and light speed in inertial frames, Einstein revolutionised the prevalent conceptions of space and time in the Special Theory of Relativity, which is not however without difficulties, due to gaping holes in its philosophical foundations. The first postulate is an unjustified and clumsily drafted extension of Galilean Relativity, while the second postulate, if interpreted as meaning that the speed of light will not be altered by a moving frame, does not lead to Lorentz transformations, but just reveals that a light ray is not transported by a moving frame. Reference frames involving light propagation do not exhibit the equivalence inherent in inertial frames, and hence could be classified as seemingly-inertial, being some category of non-inertial frames. Either equivalence, including simultaneity in both moving and stationary frames, is a defining characteristic of inertial frames, or else if inertial frames allow inequivalence, then they are not indistinguishable, which is a contradiction. All along, the definitions of “frames of reference,” “inertial frames,” and “simultaneity” and the “legal” drafting of the two postulates play a crucial role in the development and consistency of the Theory, almost as much as the thought experiments and the mathematics.
In 2016, the Planetário do Porto – Ciência Viva Center (PP-CCV) launched a new approach to its in-service teacher training plan (TTP). This plan was structured around five key elements: (i) its relevance for teacher career progression, being free of charge and open to educators of all school subjects; (ii) an inquiry-based learning design, grounded in the most updated scientific knowledge and methods; (iii) a direct alignment with the school curriculum; (iv) the use Astronomy as a vehicle for interdisciplinary learning across several school subjects; and (v) a commitment to democratizing science leveraging the school system’s multiplier effect. In this article, we present the different stages in the development of the TTP, which include institutional partnership with NASE (Network for Astronomy School Education) and EAAE (European Association for Astronomy Education). The program enrolled 3,208 teachers from all the Portuguese districts as well as from the Community of Portuguese Speaking Countries (CPLP). The PP-CCV’s TTP, practical and replicable, proved to be an effective channel for bringing cutting-edge scientific knowledge and practices to educational contexts – especially in communities with historically low engagement with science, not by choice, but due to systemic barriers in access to scientific education.
Investigations of interstellar microscopic phenomena often are in need of a simple, standardized, yet flexible approach for macrophysical evolution of evolving molecular cloud cores. With the help of a 1D model, we provide analytical functions – polynomial equations – tracking gas and dust temperature, density, and column density in seven spherical collapsing prestellar cores in the mass range from 0.5 to 30 M⊙{{\rm{M}}}_{\odot }. Seven geometrical points were sampled along the radius of each core. The resulting data represent physical conditions in parcels in the early presolar nebula and other protostellar collapsing cores. The data are adapted as testbed for models focusing on chemistry or other complex processes.
