1,110 research outputs found
Monopole Condensation and Dimensional Transmutation in SU(2) QCD
We resolve the controversy on the stability of the monopole condensation in
the one-loop effective action of SU(2) QCD by calculating the imaginary part of
the effective action with two different methods at one-loop order. Our result
confirms that the effective action for the magnetic background has no imaginary
part but the one for the electric background has a negative imaginary part.
This assures that the monopole condensation is indeed stable, but the electric
background becomes unstable due to the pair-annihilation of gluons.Comment: 13 pages, 2 figure
Stable Monopole-Antimonopole String Background in SU(2) QCD
Motivated by the instability of the Savvidy-Nielsen-Olesen vacuum we make a
systematic search for a stable magnetic background in pure SU(2) QCD. It is
shown that a pair of axially symmetric monopole and antimonopole strings is
stable, provided that the distance between the two strings is less than a
critical value. The existence of a stable monopole-antimonopole string
background strongly supports that a magnetic condensation of
monopole-antimonopole pairs can generate a dynamical symmetry breaking, and
thus the magnetic confinement of color in QCD.Comment: 7 page
Quasi-Periodic Releases of Streamer Blobs and Velocity Variability of the Slow Solar Wind near the Sun
We search for persistent and quasi-periodic release events of streamer blobs
during 2007 with the Large Angle Spectrometric Coronagraph on the \textit{Solar
and Heliospheric Observatory} and assess the velocity of the slow solar wind
along the plasma sheet above the corresponding streamer by measuring the
dynamic parameters of blobs. We find 10 quasi-periodic release events of
streamer blobs lasting for three to four days. In each day of these events, we
observe three-five blobs. The results are in line with previous studies using
data observed near the last solar minimum. Using the measured blob velocity as
a proxy for that of the mean flow, we suggest that the velocity of the
background slow solar wind near the Sun can vary significantly within a few
hours. This provides an observational manifestation of the large velocity
variability of the slow solar wind near the Sun.Comment: 14 pages, 5 figures, accepted by Soalr Physic
Phospho-regulation of the Shugoshin - Condensin interaction at the centromere in budding yeast.
Correct bioriented attachment of sister chromatids to the mitotic spindle is essential for chromosome segregation. In budding yeast, the conserved protein shugoshin (Sgo1) contributes to biorientation by recruiting the protein phosphatase PP2A-Rts1 and the condensin complex to centromeres. Using peptide prints, we identified a Serine-Rich Motif (SRM) of Sgo1 that mediates the interaction with condensin and is essential for centromeric condensin recruitment and the establishment of biorientation. We show that the interaction is regulated via phosphorylation within the SRM and we determined the phospho-sites using mass spectrometry. Analysis of the phosphomimic and phosphoresistant mutants revealed that SRM phosphorylation disrupts the shugoshin-condensin interaction. We present evidence that Mps1, a central kinase in the spindle assembly checkpoint, directly phosphorylates Sgo1 within the SRM to regulate the interaction with condensin and thereby condensin localization to centromeres. Our findings identify novel mechanisms that control shugoshin activity at the centromere in budding yeast
Quantum Yang-Mills gravity in flat space-time and effective curved space-time for motions of classical objects
Yang-Mills gravity with translational gauge group T(4) in flat space-time
implies a simple self-coupling of gravitons and a truly conserved
energy-momentum tensor. Its consistency with experiments crucially depends on
an interesting property that an `effective Riemannian metric tensor' emerges in
and only in the geometric-optics limit of the photon and particle wave
equations. We obtain Feynman rules for a coupled graviton-fermion system,
including a general graviton propagator with two gauge parameters and the
interaction of ghost particles. The equation of motion of macroscopic objects,
as an N-body system, is demonstrated as the geometric-optics limit of the
fermion wave equation. We discuss a relativistic Hamilton-Jacobi equation with
an `effective Riemann metric tensor' for the classical particles.Comment: 20 pages, to be published in "The European Physical Journal -
Plus"(2011). The final publication is available at http://www.epj.or
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