2,065 research outputs found
Failure of the local-global principle for isotropy of quadratic forms over rational function fields
We prove the failure of the local-global principle, with respect to all
discrete valuations, for isotropy of quadratic forms over a rational function
field of transcendence degree at least 2 over the complex numbers. Our
construction involves the generalized Kummer varieties considered by Borcea and
Cynk--Hulek.Comment: 7 pages, comments welcome
Helicity Conservation via the Noether Theorem
The conservation of helicity in ideal barotropic fluids is discussed from a
group theoretical point of view. A new symmetry group is introduced i.e. the
alpha group of translations. It is proven via the Noether theorem that this
group generates helicity conservation.Comment: 7 pages of te
The transcendental lattice of the sextic Fermat surface
We prove that the integral polarized Hodge structure on the transcendental
lattice of a sextic Fermat surface is decomposable. This disproves a conjecture
of Kulikov related to a Hodge theoretic approach to proving the irrationality
of the very general cubic fourfold.Comment: 15 pages; v2: minor changes, streamlined the argument in Section
Diffusional Relaxation in Random Sequential Deposition
The effect of diffusional relaxation on the random sequential deposition
process is studied in the limit of fast deposition. Expression for the coverage
as a function of time are analytically derived for both the short-time and
long-time regimes. These results are tested and compared with numerical
simulations.Comment: 9 pages + 2 figure
Insight into resolution enhancement in generalized two-dimensional correlation spectroscopy
Generalized two-dimensional correlation spectroscopy (2D-COS) can be used to enhance spectral resolution in order to help differentiate highly overlapped spectral bands. Despite the numerous extensive 2D-COS investigations, the origin of the 2D spectral resolution enhancement mechanism(s) is not completely understood. In the work here, we studied the 2D-COS of simulated spectra in order to develop new insights into the dependence of 2D-COS spectral features on the overlapping band separations, their intensities and bandwidths, and their band intensity change rates. We found that the features in the 2D-COS maps that are derived from overlapping bands were determined by the spectral normalized half-intensities and the total intensity changes of the correlated bands. We identified the conditions required to resolve overlapping bands. In particular, 2D-COS peak resolution requires that the normalized half-intensities of a correlating band have amplitudes between the maxima and minima of the normalized half-intensities of the overlapping bands. © 2013 Society for Applied Spectroscopy
The 1-soliton in the SO(3) gauged Skyrme model with mass term
The solitons of the SO(3) gauged Skyrme model with no pion-mass potential
were studied in Refs. {nl,jmp}. Here, the effects of the inclusion of this
potential are studied. In contrast with the (ungauged) Skyrme model, where the
effect of this potential on the solitons is marginal, here it turns out to be
decisive, resulting in very different dependence of the energy as a function of
the Skyrme coupling constant.Comment: new title, typos corrected, LaTeX, 8 pages, 4 figure
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