810 research outputs found
A simple solution to color confinement
We show that color confinement is a direct result of the nonabelian, i.e.
nonlinear, nature of the color interaction in quantum chromodynamics. This
makes it in general impossible to describe the color field as a collection of
elementary quanta (gluons). A quark cannot be an elementary quanta of the quark
field, as the color field of which it is the source is itself a source hence
making isolated (noninteracting) quarks impossible. In geometrical language,
the impossibility of quarks and gluons as physical particles arises due to the
fact that the color Yang-Mills space does not have a constant trivial
curvature.Comment: 6 pages, LaTe
Nonlinear gauge interactions - A solution to the "measurement problem" in quantum mechanics?
We propose that the mechanism responsible for the ``collapse of the wave
function" (or "decoherence" in its broadest meaning) in quantum mechanics is
the nonlinearities already present in the theory via nonabelian gauge
interactions. Unlike all other models of spontaneous collapse, our proposal is,
to the best of our knowledge, the only one which does not introduce any new
elements into the theory. Indeed, unless the gauge interaction nonlinearities
are not used for exactly this purpose, one must then explain why the violation
of the superposition principle which they introduce does not destroy quantum
mechanics. A possible experimental test of the model would be to compare the
coherence lengths for, e.g., electrons and photons in a double-slit experiment.
The electrons should have a finite coherence length, while photons should have
a much longer (in principle infinite) coherence length.Comment: 7 pages, LaTe
Newtonian Quantum Gravity
A Newtonian approach to quantum gravity is studied. At least for weak
gravitational fields it should be a valid approximation. Such an approach could
be used to point out problems and prospects inherent in a more exact theory of
quantum gravity, yet to be discovered. Newtonian quantum gravity, e.g., shows
promise for prohibiting black holes altogether (which would eliminate
singularities and also solve the black hole information paradox), breaks the
equivalence principle of general relativity, and supports non-local
interactions (quantum entanglement). Its predictions should also be testable at
length scales well above the "Planck scale", by high-precision experiments
feasible even with existing technology. As an illustration of the theory, it
turns out that the solar system, superficially, perfectly well can be described
as a quantum gravitational system, provided that the quantum number has its
maximum value, . This results exactly in Kepler's third law. If also the
quantum number has its maximum value () the probability density has
a very narrow torus-like form, centered around the classical planetary orbits.
However, as the probability density is independent of the azimuthal angle
there is, from quantum gravity arguments, no reason for planets to be
located in any unique place along the orbit (or even \textit{in} an orbit for
). This is, in essence, a reflection of the "measurement problem"
inherent in all quantum descriptions
"Quantum machine" to solve quantum "measurement problem"?
Recently a study of the first superposed mechanical quantum object
("machine") visible to the naked eye was published. However, as we show, it
turns out that if the object would actually be observed, i.e. would interact
with an optical photon, the quantum behavior should vanish. This, the actual
observation, has long been suspected in many interpretations of quantum
mechanics to be what makes the transition quantum classical, but
so far it has not been available for direct experimental study in a mechanical
system. We show how any interaction, even a purely quantum one, of sufficient
strength can constitute a physical "measurement" - essentially the emergence of
an effectively classical object - active observation thus being a sufficient
but not necessary criterion. So it seems we have in this case of the "quantum
machine" a unique possibility to study, and possibly solve, the long-standing
"measurement problem" of quantum mechanics.Comment: 4 page
Aspects of nonrelativistic quantum gravity
A nonrelativistic approach to quantum gravity is studied. At least for weak
gravitational fields it should be a valid approximation. Such an approach can
be used to point out problems and prospects inherent in a more exact theory of
quantum gravity, yet to be discovered. Nonrelativistic quantum gravity, e.g.,
shows promise for prohibiting black holes altogether (which would eliminate
singularities and also solve the black hole information paradox), gives
gravitational radiation even in the spherically symmetric case, and supports
non-locality (quantum entanglement). Its predictions should also be testable at
length scales well above the "Planck scale", by high-precision experiments
feasible with existing technology.Comment: Accepted for publicatio
Nonlinear gauge interactions: a possible solution to the "measurement problem" in quantum mechanics
Two fundamental, and unsolved problems in physics are: i) the resolution of
the "measurement problem" in quantum mechanics ii) the quantization of strongly
nonlinear (nonabelian) gauge theories. The aim of this paper is to suggest that
these two problems might be linked, and that a mutual, simultaneous solution to
both might exist. We propose that the mechanism responsible for the "collapse
of the wave function" in quantum mechanics is the nonlinearities already
present in the theory via nonabelian gauge interactions. Unlike all other
models of spontaneous collapse, our proposal is, to the best of our knowledge,
the only one which does not introduce any new elements into the theory. A
possible experimental test of the model would be to compare the coherence
lengths - here defined as the distance over which quantum mechanical
superposition is still valid - for, \textit{e.g}, electrons and photons in a
double-slit experiment. The electrons should have a finite coherence length,
while photons should have a much longer coherence length (in principle
infinite, if gravity - a very weak effect indeed unless we approach the Planck
scale - is ignored).Comment: 11 pages, Accepted for publicatio
The "proton spin crisis" - a quantum query
The "proton spin crisis" was introduced in the late 1980s, when the
EMC-experiment revealed that little or nothing of a proton's spin seemed to be
carried by its quarks. The main objective of this paper is to point out that it
is wrong to assume that the proton spin, measured by completely different
experimental setups, should be the same in all circumstances.Comment: 5 page
Luminosities of High-Redshift Objects in an Accelerating Universe
The results from the Supernova Cosmology Project indicate a relation between
cosmic distance and redshift that corresponds to an accelerating Universe, and,
as a consequence, the presence of an energy component with negative pressure.
This necessitates a re-evaluation of such astrophysical luminosities that have
been derived through conventional redshift analyses of, e.g., gamma-ray bursts
and quasars. We have calculated corrected luminosity distances within two
scenarios; the standard one with a non-zero cosmological constant, and the more
recently proposed ``quintessence'', with a slowly evolving energy-density
component. We find luminosity corrections from +30 to -40 per cent for
redshifts with . This finding implicates that the SCP data do not, by
themselves, require a revision of the current, rather qualitative modeling of
gamma-ray bursts and quasar properties.Comment: RevTeX, 4 pages, 2 postscript figures, submitted to PR
A hierarchy of cosmic compact objects - without black holes
We make the case for the existence of a, hitherto unknown and unobserved,
hierarchy of ever more compact cosmic objects in the universe. This hypothesis
is based on i) the assumption of "elementary" particle sub-constituents on
several levels below the presently known, inspired by Glashow's "blooming
desert", ii) the existence of nearly scale-invariant density fluctuations in
the early universe, e.g. as predicted by inflationary models, iii) our own
previous theoretical work showing that a class of objects considerably more
compact than previously thought possible in astrophysics can exist. We also
give several independent arguments strongly pointing towards the non-existence
of black holes. Some brief suggestions on observational signals due to the
hierarchy, both in collected astronomical data and in possible future
observations, concludes the paper
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