94,687 research outputs found
Experimental Signatures of Fermiophobic Higgs bosons
The most general Two Higgs Doublet Model potential without explicit CP
violation depends on 10 real independent parameters. Excluding spontaneous CP
violation results in two 7 parameter models. Although both models give rise to
5 scalar particles and 2 mixing angles, the resulting phenomenology of the
scalar sectors is different. If flavour changing neutral currents at tree level
are to be avoided, one has, in both cases, four alternative ways of introducing
the fermion couplings. In one of these models the mixing angle of the CP even
sector can be chosen in such a way that the fermion couplings to the lightest
scalar Higgs boson vanishes. At the same time it is possible to suppress the
fermion couplings to the charged and pseudo-scalar Higgs bosons by
appropriately choosing the mixing angle of the CP odd sector. We investigate
the phenomenology of both models in the fermiophobic limit and present the
different branching ratios for the decays of the scalar particles. We use the
present experimental results from the LEP collider to constrain the models.Comment: 23 pages, 18 figures included, newer experimental data include
Mott-insulator phases of non-locally coupled 1D dipolar Bose gases
We analyze the Mott-insulator phases of dipolar bosonic gases placed in
neighboring but unconnected 1D traps. Whereas for short-range interactions the
1D systems are independent, the non-local dipole-dipole interaction induces a
direct Mott-insulator to pair-superfluid transition which significantly
modifies the boundaries of the lowest Mott-insulator phases. The lowest
boundary of the lowest Mott regions becomes progressively constant as a
function of the hopping rate, eventually inverting its slope, leading to a
re-entrant configuration which is retained in 2D. We discuss the consequences
of this effect on the spatial Mott-insulator plateaux in experiments with
additional harmonic confinement, showing that anti-intuitively the plateaux may
become wider for increasing hopping. Our results are also applicable to
non-dipolar boson-boson mixtures.Comment: 4 pages, 4 eps figures; minor changes, reference adde
At the heart of the matter: household debt in contemporary banking and the international crisis
Demand, Production, and the Determinants of Distribution: A Caveat on "Wage-Led Growth"
The incomes of workers and capitalists pertain to different moments of accumulation. Wages are shares of capital outlays sustaining production; profits are shares of commodity sales. If aggregate demand and the scale of productive undertakings are shaped with a measure of mutual autonomy, the class distribution of income and the measure of economic activity are jointly determined by the same processes. In those settings “wage-led growth” has neither analytical nor policy purchase as associations between wage shares and levels of output (or growth) are confounded consequences of distinct effects on each measure of broader developments in the economy. A more appropriate dichotomy is that between “investment-led” and “consumption-led” growth, with the former resulting in comparatively higher wage shares. After advancing and illustrating these points, this paper motivates its approach to class income flows and the role of demand--which draw on the Circuit of Capital--in relation to the equivalent Kaleckian approaches sustaining arguments for “wage-led growth”
Phonon instability in two-dimensional dipolar Bose-Einstein Condensates
The partially attractive character of the dipole-dipole interaction leads to
phonon instability in dipolar condensates, which is followed by collapse in
three-dimensional geometries. We show that the nature of this instability is
fundamentally different in two-dimensional condensates, due to the
dipole-induced stabilization of two-dimensional bright solitons. As a
consequence, a transient gas of attractive solitons is formed, and collapse may
be avoided. In the presence of an harmonic confinement, the instability leads
to transient pattern formation followed by the creation of stable
two-dimensional solitons. This dynamics should be observable in on-going
experiments, allowing for the creation of stable two-dimensional solitons for
the first time ever in quantum gases.Comment: 4 pages, 4 figure
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