56,876 research outputs found
Generalized Log-Normal Chain-Ladder
We propose an asymptotic theory for distribution forecasting from the log
normal chain-ladder model. The theory overcomes the difficulty of convoluting
log normal variables and takes estimation error into account. The results
differ from that of the over-dispersed Poisson model and from the chain-ladder
based bootstrap. We embed the log normal chain-ladder model in a class of
infinitely divisible distributions called the generalized log normal
chain-ladder model. The asymptotic theory uses small asymptotics where
the dimension of the reserving triangle is kept fixed while the standard
deviation is assumed to decrease. The resulting asymptotic forecast
distributions follow t distributions. The theory is supported by simulations
and an empirical application
Explaining Phenomenologically Observed Space-time Flatness Requires New Fundamental Scale Physics
The phenomenologically observed flatness - or near flatness - of spacetime
cannot be understood as emerging from continuum Planck (or sub-Planck) scales
using known physics. Using dimensional arguments it is demonstrated that any
immaginable action will lead to Christoffel symbols that are chaotic. We put
forward new physics in the form of fundamental fields that spontaneously break
translational invariance. Using these new fields as coordinates we define the
metric in such a way that the Riemann tensor vanishes identically as a Bianchi
identity. Hence the new fundamental fields define a flat space. General
relativity with curvature is recovered as an effective theory at larger scales
at which crystal defects in the form of disclinations come into play as the
sources of curvature.Comment: This article were already in 2011 published as Proceedings of the
14th Bled Conference on "What Comes Beyond the Standard Models" organized by
Norma Manko Borstnik, Dragan Lukman, Maxim Khlopov, and H.B. Nielse
Products of Random Matrices
We derive analytic expressions for infinite products of random 2x2 matrices.
The determinant of the target matrix is log-normally distributed, whereas the
remainder is a surprisingly complicated function of a parameter characterizing
the norm of the matrix and a parameter characterizing its skewness. The
distribution may have importance as an uncommitted prior in statistical image
analysis.Comment: 9 pages, 1 figur
Fermion and Higgs Masses and the AGUT Model
We present two rather differently based predictions for the quark and lepton
spectrum: One provides a rather successful fit to the mass suppressions---the
well known fermion mass hierarchy---interpreted as due to most mass terms
needing to violate approximately conserved quantum numbers corresponding to the
AGUT group . This is actually, under certain conditions,
the maximal group transforming the known 45 Weyl components of the quark and
leptons into each other. From the fit to the fermion spectrum, we get a picture
of the series of Higgs fields causing the breakdown (presumably at the Planck
scale) of this AGUT to the Standard Model and, thus, providing the small masses
of all quarks and leptons except for the top quark. We separately predict the
top quark mass to be GeV and the Higgs mass to be GeV,
from the assumption that there be two degenerate minima in the effective
potential for the Weinberg Salam Higgs field with the second one at the Planck
field strength.Comment: 6 page LaTeX file plus 1 postscript figure and aipproc style file,
uses epsfig.sty; to appear in the Proceedings of Beyond the Standard Model V,
Balholm, Norway, 29 April - 4 May 199
Tunguska Dark Matter Ball
It is suggested that the Tunguska event in June 1908 cm-large was due to a
cm-large ball of a condensate of bound states of 6 top and 6 anti-top quarks
containing highly compressed ordinary matter. Such balls are supposed to make
up the dark matter as we earlier proposed. The expected rate of impact of this
kind of dark matter ball with the earth seems to crudely match a time scale of
200 years between the impacts. The main explosion of the Tunguska event is
explained in our picture as material coming out from deep within the earth,
where it has been heated and compressed by the ball penetrating to a depth of
several thousand km. Thus the effect has some similarity with volcanic activity
as suggested by Kundt. We discuss the possible identification of kimberlite
pipes with earlier Tunguska-like events. A discussion of how the dark matter
balls may have formed in the early universe is also given.Comment: In second version some typos and smaller miscalculations were change
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