1,460 research outputs found
An Empirical Evaluation of The Relationship of Market Value Added with Internal Company Characteristics
The window dressing of jinanc/al statements creates problems for
investment decision making. This necessitates the use of other measures
that capture the fundamental economic reality of the organization. This
paper seeks to examine the relationship between market value added and
the internal performance characteristics and how this affects share
prices.
The paper using OLS regression technique shows that Market Value
Added is highly correlated with Economic Value Added than other
internal company characteristics. The import of this is that, for
management to increase market value added it must concentrate on
increasing its Economic Value Adde
CP violation in unpolarized e^+ e^- to charginos at one loop level
We study CP violation in e^+ e^- to \tilde\chi_i^+\tilde\chi_j^- in the
framework of the MSSM. Though the cross section of this process is CP-even at
the tree level even for polarized electron-positron beams, we show that it
contains a CP-odd part at the one loop order and there are CP-odd observables
that can in principle be measured even using unpolarized electron-positron
beams. The relevant diagram calculations are briefly discussed and the results
of selected (box) diagram computations are shown.Comment: similar to Phys. Rev. D version, but corrected figs. 4, 5, 6 (factor
four
Multi-lepton Signatures of a Hidden Sector in Rare B Decays
We explore the sensitivity of flavour changing b -> s transitions to a
(sub-)GeV hidden sector with generic couplings to the Standard Model through
the Higgs, vector and axion portals. The underlying two-body decays of B
mesons, B -> X_s S and B0 -> SS, where S denotes a generic new GeV-scale
particle, may significantly enhance the yield of monochromatic lepton pairs in
the final state via prompt decays of S to a dilepton pair. Existing
measurements of the charged lepton spectrum in neutral-current semileptonic B
decays provide bounds on the parameters of the light sector that are
significantly more stringent than the requirements of naturalness. New search
modes, such as B -> X_s + n(l+l-) and B0 -> n(l+l-) with n > 1 can provide
additional sensitivity to scenarios in which both the Higgs and vector portals
are active, and are accessible to (super-)B factories and hadron colliders.Comment: 12 pages, 2 figures; v2: reference added, minor correction
Constraints on the variability of quark masses from nuclear binding
Based on recent work on nuclear binding, we update and extend the anthropic
constraints on the light quark masses, with results that are more tightly
constrained than previously obtained. We find that heavy nuclei would fall
apart (because the attractive nuclear central potential becomes too weak) if
the sum of the light quark masses m_u+m_d would exceed their physical values by
64% (at 95% confidence level). We summarize the anthropic constraints that
follow from requiring the existence both of heavy atoms and of hydrogen. With
the additional assumption that the quark Yukawa couplings do not vary, these
constraints provide a remarkably tight anthropic window for the Higgs vacuum
expectation value: 0.39 < v/v_physical < 1.64.Comment: 21 pages, 7 figure
Lepton Polarization in the Decays and
The effective Hamiltonian for the decay predicts a
characteristic polarization for the final state lepton, which can serve as an
important test of the underlying theory. The lepton polarization has, in
addition to a longitudinal component , two orthogonal components and
, lying in and perpendicular to the decay plane which are proportional to
, and therefore significant for the channel. The normal
polarization component is a -odd effect connected with the
nonhermiticity of the effective Hamiltonian, arising mainly from
intermediate states. We calculate all three polarization components for the
decay as a function of the lepton pair mass, and find
average values = -0.63, = 0.03. By comparison,
the $\mu^-$ polarization is = -0.77, .Comment: 17 pages, LaTeX, 5 eps figures, uses epsf.sty and cite.st
Models of Electroweak Interactions in Non-Commutative Geometry: A Comparison
Alain Connes' construction of the standard model is based on a generalized
Dirac-Yukawa operator and the K-cycle (\HD ,D), with \HD a fermionic
Hilbert space. If this construction is reformulated at the level of the
differential algebra then a direct comparison with the alternative approach by
the Marseille-Mainz group becomes possible. We do this for the case of the toy
model based on the structure group and for the of electroweak interactions. Connes' results are recovered without the
somewhat disturbing -factors in the fermion mass terms and Yukawa
couplings. We discuss both constructions in the same framework and, in
particular, pinpoint the origin of the difference in the Higgs potential
obtained by them.Comment: 9p, MZ-TH/93-2
`c' is the speed of light, isn't it?
Theories proposing a varying speed of light have recently been widely
promoted under the claim that they offer an alternative way of solving the
standard cosmological problems. Recent observational hints that the fine
structure constant may have varied during over cosmological scales also has
given impetus to these models. In theoretical physics the speed of light, ,
is hidden in almost all equations but with different facets that we try to
distinguish. Together with a reminder on scalar-tensor theories of gravity,
this sheds some light on these proposed varying speed of light theories.Comment: 14 pages, Late
Neutrino statistics and big bang nucleosynthesis
Neutrinos may possibly violate the spin-statistics theorem, and hence obey
Bose statistics or mixed statistics despite having spin half. We find the
generalized equilibrium distribution function of neutrinos which depends on a
single fermi-bose parameter, \kappa, and interpolates continuously between the
bosonic and fermionic distributions when \kappa changes from -1 to +1. We
consider modification of the Big Bang Nucleosynthesis (BBN) in the presence of
bosonic or partly bosonic neutrinos. For pure bosonic neutrinos the abundances
change (in comparison with the usual Fermi-Dirac case) by -3.2% for 4He (which
is equivalent to a decrease of the effective number of neutrinos by \Delta
N_\nu = - 0.6), +2.6% for 2H and -7% for 7Li. These changes provide a better
fit to the BBN data. Future BBN studies will be able to constrain the
fermi-bose parameter to \kappa > 0.5, if no deviation from fermionic nature of
neutrinos is found. We also evaluate the sensitivity of future CMB and LSS
observations to the fermi-bose parameter.Comment: 11 pages, 3 figures, matches version in JCAP, discussion and
references extended slightl
't Hooft tensor for generic gauge group
We study monopoles in gauge theories with generic gauge group. Magnetic
charges are in one-to-one correspondence with the second homotopy classes at
spatial infinity (), which are therefore identified by the 't Hooft
tensor. We determine the 't Hooft tensor in the general case. These issues are
relevant to the understanding of Color Confinement.Comment: 5 pages. Contribution to the Conference QCD08, Montpellier 7-12 July
2008 To appear in the proceeding
Final-State-Interaction Simulation of T-Violation in the Top-Quark Semileptonic Decay
The standard electroweak final-state interaction induces a false T-odd
correlation in the top-quark semileptonic decay. The correlation parameter is
calculated in the standard model and found to be considerably larger than those
that could be produced by genuine T-violation effects in a large class of
theoretical models.Comment: 14 pages, 1 diagram (not included
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