Jeans Research Articles

Can cold dark matter paradigm explain the central-surface-densities relation?

Recently, a very strong correlation between the central surface density of stars and dynamical mass in 135 disk galaxies has been obtained. It has been shown that this central-surface-densities relation agrees very well with Modified Newtonian Dynamics (MOND). In this article, we show that if we assume the baryons have an isothermal distribution and dark matter exists, then it is possible to derive by means of the Jeans equation an analytic central-surface-densities relation connecting dark matter and baryons that agrees with the observed relation. We find that the observed central-surface-densities relation can also be accommodated in the context of dark matter provided the latter is described by an isothermal profile. Therefore, the observed relation is consistent with not only MOND.

The Effect of Radiation on the Jeans Instability of a Viscous Quantum Plasma with Finite Electrical Resistivity

The effect of the radiative heat-loss function on the Jeans instability of a quantum plasma, in the presence of finite electrical resistivity and viscosity, is investigated. A general dispersion relation is derived from the linearized perturbation equations using normal mode analysis and discussed for the longitudinal and transverse direction of wave propagation. On the basis of the Routh-Hurwitz criterion, the dynamic stability of the system is discussed. The condition for the Jeans instability of a quantum plasma is discussed in the different cases of our interest. It is found that, owing to the inclusion of a radiative heat-loss function and thermal conductivity, the Jeans criterion of gravitational instability changes into a radiative instability criteria. For the transverse mode, in the case of a resistive medium the expression of the Jeans instability is independent of the magnetic field, while for a perfectly conducting medium the magnetic field gives a stabilizing effect. From the curves it is apparent that the viscosity, temperature dependent heat-loss function, and magnetic field stabilize the system, while the electrical resistivity has a destabilizing effect.

A Study on Jeans Fashion Styling - Focused on the Women's Fashion since the 2000s -

The jeans fashion has important meaning as the symbol of sociocultural phenomenon related with modern fashion. It became the symbol of natural fashion beauty representing freedom and equality and sometimes the sensual style. This study defined the meaning, element, and importance of fashion styling by analyzing preliminary studies and analyzed the aesthetic characteristics of the jeans fashion. The purpose of this study is to drive four styling patterns of the jeans fashion based on such theoretical studies and empirical researches about jeans fashion and plan and direct jeans fashion styling for each style. The results also provides the basis for acknowledging that the idea of 'directing and creating a style' according to a person's intent beyond the one-dimensional idea of simply 'wearing' clothes is the true fashion styling and will set an important footing in the fashion field with the ideas that fit the 21st century.

From Confederate Overalls to Designer Jeans

L'A. propose une comparaison de la variation lexicale dans le Linguistic Atlas of the Gulf States (dont le travail de terrain a ete realise depuis le milieu des annees 70 jusqu'au debut des annees 80) et dans le Linguistic Atlas of the Middle and South Atlantic States (dont le travail de terrain a ete realise dans les annees 30 et 40). Les resultats de cette etude indiquent que la distinction entre le vocabulaire rural et le vocabulaire urbain n'est pas un phenomene nouveau et qu'il etait deja manifeste dans les annees 30-40. En outre, cette etude permet de souligner le fait que le vocabulaire populaire du sud est en train de disparaitre pour etre remplace par un modele plus national

Sir James Hopwood Jeans

Sir James Hopwood Jeans

Sir James H. Jeans

Sir James H. Jeans

“The House that Jeans Built”

“The House that Jeans Built”

LVII. Note on Mr. Jeans' letter in Phil. Mag. for December

LVII. <i>Note on Mr. Jeans' letter in Phil. Mag. for December</i>

LXV. Mr. J. H. Jeans' theory of gases

LXV. <i>Mr. J. H. Jeans' theory of gases</i>

James Wm. Jeans, Esq., of Grantham, Lincolnshire

James Wm. Jeans, Esq., of Grantham, Lincolnshire