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Corpus-Based Transcription as an Approach to the Compositional Control of Timbre
Timbre space is a cognitive model useful to address the problem of structuring timbre in electronic music. The recent concept of corpus-based concatenative sound synthesis is proposed as an approach to timbral control in both real- and deferred-time applications. Using CataRT and related tools in the FTM and Gabor libraries for Max/MSP we describe a technique for real-time analysis of a live signal to pilot corpus-based synthesis, along with examples of compositional realizations in works for instruments, electronics, and sound installation. To extend this technique to computer-assisted composition for acoustic instruments, we develop tools using the Sound Description Interchange Format (SDIF) to export sonic descriptors to OpenMusic where they may be further manipulated and transcribed into an instrumental score. This presents a flexible technique for the compositional organization of noise-based instrumental sounds
Potential contributions of noncontact atomic force microscopy for the future Casimir force measurements
Surface electric noise, i.e., the non-uniform distribution of charges and
potentials on a surface, poses a great experimental challenge in modern
precision force measurements. Such a challenge is encountered in a number of
different experimental circumstances. The scientists employing atomic force
microscopy (AFM) have long focused their efforts to understand the
surface-related noise issues via variants of AFM techniques, such as Kelvin
probe force microscopy or electric force microscopy. Recently, the physicists
investigating quantum vacuum fluctuation phenomena between two closely-spaced
objects have also begun to collect experimental evidence indicating a presence
of surface effects neglected in their previous analyses. It now appears that
the two seemingly disparate science communities are encountering effects rooted
in the same surface phenomena. In this report, we suggest specific experimental
tasks to be performed in the near future that are crucial not only for
fostering needed collaborations between the two communities, but also for
providing valuable data on the surface effects in order to draw the most
realistic conclusion about the actual contribution of the Casimir force (or van
der Waals force) between a pair of real materials.Comment: The paper appeared in the Proceedings to the 12th International
Conference on Noncontact Atomic Force Microscopy (NC-AFM 2009) and Casimir
2009 Satellite Worksho
Formation of small-scale structure in SUSY CDM
The lightest supersymmetric particle, most likely the lightest neutralino, is
one of the most prominent particle candidates for cold dark matter (CDM). We
show that the primordial spectrum of density fluctuations in neutralino CDM has
a sharp cut-off, induced by two different damping mechanisms. During the
kinetic decoupling of neutralinos, non-equilibrium processes constitute
viscosity effects, which damp or even absorb density perturbations in CDM.
After the last scattering of neutralinos, free streaming induces neutralino
flows from overdense to underdense regions of space. Both damping mechanisms
together define a minimal mass scale for perturbations in neutralino CDM,
before the inhomogeneities enter the nonlinear epoch of structure formation. We
find that the very first gravitationally bound neutralino clouds ought to have
masses above 10^{-6} solar masses, which is six orders of magnitude above the
mass of possible axion miniclusters.Comment: 7 pages, 3 figures, to appear in proceedings of "IDM 2002, 4th
International Workshop on the Identification of Dark Matter
Scale dependence of cosmological backreaction
Due to the non-commutation of spatial averaging and temporal evolution,
inhomogeneities and anisotropies (cosmic structures) influence the evolution of
the averaged Universe via the cosmological backreaction mechanism. We study the
backreaction effect as a function of averaging scale in a perturbative approach
up to higher orders. We calculate the hierarchy of the critical scales, at
which 10% effects show up from averaging at different orders. The dominant
contribution comes from the averaged spatial curvature, observable up to scales
of 200 Mpc. The cosmic variance of the local Hubble rate is 10% (5%) for
spherical regions of radius 40 (60) Mpc. We compare our result to the one from
Newtonian cosmology and Hubble Space Telescope Key Project data.Comment: 6 pages, 2 figures; v3: substantial modifications, new figure
Effects of weak self-interactions in a relativistic plasma on cosmological perturbations
The exact solutions for linear cosmological perturbations which have been
obtained for collisionless relativistic matter within thermal field theory are
extended to a self-interacting case. The two-loop contributions of scalar
theory to the thermal graviton self-energy are evaluated, which
give the corrections in the perturbation equations. The changes
are found to be perturbative on scales comparable to or larger than the Hubble
horizon, but the determination of the large-time damping behavior of subhorizon
perturbations requires a resummation of thermally induced masses.Comment: 11 pages, REVTEX, 4 postscript figures included by epsf.sty -
expanded version (more details on the resummation of thermal masses which is
required for the late-time damping behaviour
Solomon Islands national situation analysis
The CGIAR Research Program on Aquatic Agricultural Systems (CRP AAS) was approved by the CGIAR Fund Council in July, 2011. Solomon Islands, one of five countries targeted by the program, began its rollout with a five month planning phase between August and December of 2011. Subsequent steps of the Program rollout include scoping, diagnosis and design. This report is the first to be produced during the scoping phase in Solomon Islands; it addresses the national setting and provides basic information on the context within which the AAS Program will operate. The macro level subjects of analysis provide initial baselines of national level indicators, policy context, power relationships and other factors relevant to the Program
Hyperuniformity with no fine tuning in sheared sedimenting suspensions
Particle suspensions, present in many natural and industrial settings,
typically contain aggregates or other microstructures that can complicate
macroscopic flow behaviors and damage processing equipment. Recent work found
that applying uniform periodic shear near a critical transition can reduce
fluctuations in the particle concentration across all length scales, leading to
a hyperuniform state. However, this strategy for homogenization requires fine
tuning of the strain amplitude. Here we show that in a model of sedimenting
particles under periodic shear, there is a well-defined regime at low
sedimentation speed where hyperuniform scaling automatically occurs. Our
simulations and theoretical arguments show that the homogenization extends up
to a finite lengthscale that diverges as the sedimentation speed approaches
zero.Comment: 11 pages, 6 figure
Occam's razor meets WMAP
Using a variety of quantitative implementations of Occam's razor we examine
the low quadrupole, the ``axis of evil'' effect and other detections recently
made appealing to the excellent WMAP data. We find that some razors {\it fully}
demolish the much lauded claims for departures from scale-invariance. They all
reduce to pathetic levels the evidence for a low quadrupole (or any other low
cut-off), both in the first and third year WMAP releases. The ``axis of
evil'' effect is the only anomaly examined here that survives the humiliations
of Occam's razor, and even then in the category of ``strong'' rather than
``decisive'' evidence. Statistical considerations aside, differences between
the various renditions of the datasets remain worrying
Direct certification of a class of quantum simulations
One of the main challenges in the field of quantum simulation and computation
is to identify ways to certify the correct functioning of a device when a
classical efficient simulation is not available. Important cases are situations
in which one cannot classically calculate local expectation values of state
preparations efficiently. In this work, we develop weak-membership formulations
of the certification of ground state preparations. We provide a non-interactive
protocol for certifying ground states of frustration-free Hamiltonians based on
simple energy measurements of local Hamiltonian terms. This certification
protocol can be applied to classically intractable analog quantum simulations:
For example, using Feynman-Kitaev Hamiltonians, one can encode universal
quantum computation in such ground states. Moreover, our certification protocol
is applicable to ground states encodings of IQP circuits demonstration of
quantum supremacy. These can be certified efficiently when the error is
polynomially bounded.Comment: 10 pages, corrected a small error in Eqs. (2) and (5
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