3,533 research outputs found
Nitrogen Trichloride with Benzalacetophenone
Nitrogen trichloride and benzalacetophenone in carbon tetrachloride solution between 20° and -15 ° react to form free nitrogen, ammonium chloride, benzalacetophenone dichloride, and a C-chloro-N -dichloroamino ketone. This compound can be reduced to the C-chloroamino ketone by means of concentrated hydrochloric acid. The hydrochloride and the benzoyl derivative of this compound were isolated and analyzed
Heavy Quark Potential from Gauge/Gravity Duality: A Large D Analysis
The heavy-quark potential is calculated in the framework of gauge/gravity
duality using the large-D approximation, where D is the number of dimensions
transverse to the flux tube connecting a quark and an antiquark in a flat
D+2-dimensional spacetime. We find that in the large-D limit the leading
correction to the ground-state energy, as given by an effective Nambu-Goto
string, arises not from the heavy modes but from the behavior of the massless
modes in the vicinity of the quark and the antiquark. We estimate this
correction and find that it should be visible in the near-future lattice QCD
calculations of the heavy-quark potential.Comment: 22 pages, 5 Figures. v2: references added, typos corrected and, Sec.
4 rewritten with an expanded non-perturbative discussion of the corrections
to the Arvis potential arising from the massless modes near the boundary of
the qcd strin
Chabauty-Coleman experiments for genus 3 hyperelliptic curves
We describe a computation of rational points on genus 3 hyperelliptic curves
defined over whose Jacobians have Mordell-Weil rank 1. Using
the method of Chabauty and Coleman, we present and implement an algorithm in
Sage to compute the zero locus of two Coleman integrals and analyze the finite
set of points cut out by the vanishing of these integrals. We run the algorithm
on approximately 17,000 curves from a forthcoming database of genus 3
hyperelliptic curves and discuss some interesting examples where the zero set
includes global points not found in .Comment: 18 page
Probing the Planck Scale with Neutrino Oscillations
Quantum gravity "foam", among its various generic Lorentz non-invariant
effects, would cause neutrino mixing. It is shown here that, if the foam is
manifested as a nonrenormalizable effect at scale M, the oscillation length
generically decreases with energy as (E/M)^(-2). Neutrino observatories and
long-baseline experiments should have therefore already observed foam-induced
oscillations, even if M is as high as the Planck energy scale. The null
results, which can be further strengthened by better analysis of current data
and future experiments, can be taken as experimental evidence that Lorentz
invariance is fully preserved at the Planck scale, as is the case in critical
string theory.Comment: 11 pages, 2 figures. Final version published in PRD. 1 figure,
references, clarifications and explanations added. Results unchange
Significant Conditions on the Two-electron Reduced Density Matrix from the Constructive Solution of N-representability
We recently presented a constructive solution to the N-representability
problem of the two-electron reduced density matrix (2-RDM)---a systematic
approach to constructing complete conditions to ensure that the 2-RDM
represents a realistic N-electron quantum system [D. A. Mazziotti, Phys. Rev.
Lett. 108, 263002 (2012)]. In this paper we provide additional details and
derive further N-representability conditions on the 2-RDM that follow from the
constructive solution. The resulting conditions can be classified into a
hierarchy of constraints, known as the (2,q)-positivity conditions where the q
indicates their derivation from the nonnegativity of q-body operators. In
addition to the known T1 and T2 conditions, we derive a new class of
(2,3)-positivity conditions. We also derive 3 classes of (2,4)-positivity
conditions, 6 classes of (2,5)-positivity conditions, and 24 classes of
(2,6)-positivity conditions. The constraints obtained can be divided into two
general types: (i) lifting conditions, that is conditions which arise from
lifting lower (2,q)-positivity conditions to higher (2,q+1)-positivity
conditions and (ii) pure conditions, that is conditions which cannot be derived
from a simple lifting of the lower conditions. All of the lifting conditions
and the pure (2,q)-positivity conditions for q>3 require tensor decompositions
of the coefficients in the model Hamiltonians. Subsets of the new
N-representability conditions can be employed with the previously known
conditions to achieve polynomially scaling calculations of ground-state
energies and 2-RDMs of many-electron quantum systems even in the presence of
strong electron correlation
A deep Large Binocular Telescope view of the Canes Venatici I dwarf galaxy
We present the first deep color-magnitude diagram of the Canes Venatici I
(CVnI) dwarf galaxy from observations with the wide field Large Binocular
Camera on the Large Binocular Telescope. Reaching down to the main-sequence
turnoff of the oldest stars, it reveals a dichotomy in the stellar populations
of CVnI: it harbors an old (> 10 Gyr), metal-poor ([Fe/H] ~ -2.0) and spatially
extended population along with a much younger (~ 1.4-2.0 Gyr), 0.5 dex more
metal-rich, and spatially more concentrated population. These young stars are
also offset by 64_{-20}^{+40} pc to the East of the galaxy center. The data
suggest that this young population, which represent ~ 3-5 % of the stellar mass
of the galaxy within its half-light radius, should be identified with the
kinematically cold stellar component found by Ibata et al. (2006). CVnI
therefore follows the behavior of the other remote MW dwarf spheroidals which
all contain intermediate age and/or young populations: a complex star formation
history is possible in extremely low-mass galaxies.Comment: 4 pages, 3 figures, accepted for publication in ApJL. Minor changes,
conclusions unchange
The Exact Critical Bubble Free Energy and the Effectiveness of Effective Potential Approximations
To calculate the temperature at which a first-order cosmological phase
transition occurs, one must calculate , the free energy of a critical
bubble configuration. is often approximated by the classical energy
plus an integral over the bubble of the effective potential; one must choose a
method for calculating the effective potential when . We test different
effective potential approximations at one loop. The agreement is best if one
pulls a factor of into the decay rate prefactor [where ], and takes the real part of the effective potential in the region
. We perform a similar analysis on the 1-dimensional kink.Comment: 11 pages plus 3 figures in jyTeX; CALT-68-188
On touching random surfaces, two-dimensional quantum gravity and non-critical string theory
A set of physical operators which are responsible for touching interactions
in the framework of c<1 unitary conformal matter coupled to 2D quantum gravity
is found. As a special case the non-critical bosonic strings are considered.
Some analogies with four dimensional quantum gravity are also discussed, e.g.
creation-annihilation operators for baby universes, Coleman mechanism for the
cosmological constant.Comment: 22 pages, Latex2e, 3 figure
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