293 research outputs found
A perception and manipulation system for collecting rock samples
An important part of a planetary exploration mission is to collect and analyze surface samples. As part of the Carnegie Mellon University Ambler Project, researchers are investigating techniques for collecting samples using a robot arm and a range sensor. The aim of this work is to make the sample collection operation fully autonomous. Described here are the components of the experimental system, including a perception module that extracts objects of interest from range images and produces models of their shapes, and a manipulation module that enables the system to pick up the objects identified by the perception module. The system was tested on a small testbed using natural terrain
Instanton Calculus in R-R 3-form Background and Deformed N=2 Super Yang-Mills Theory
We study the ADHM construction of instantons in N=2 supersymmetric Yang-Mills
theory deformed in constant Ramond-Ramond (R-R) 3-form field strength
background in type IIB superstrings. We compare the deformed instanton
effective action with the effective action of fractional D3/D(-1) branes at the
orbifold singularity of C^2/Z_2 in the same R-R background. We find discrepancy
between them at the second order in deformation parameters, which comes from
the coupling of the translational zero modes of the D(-1)-branes to the R-R
background. We improve the deformed action by adding a term with space-time
dependent gauge coupling. Although the space-time action differs from the
action in the omega-background, both actions lead to the same instanton
equations of motion at the lowest order in gauge coupling.Comment: 27 pages, version to appear in JHE
Deformation of Super Yang-Mills Theories in R-R 3-form Background
We study deformation of N=2 and N=4 super Yang-Mills theories, which are
obtained as the low-energy effective theories on the (fractional) D3-branes in
the presence of constant Ramond-Ramond 3-form background. We calculate the
Lagrangian at the second order in the deformation parameter from open string
disk amplitudes. In N=4 case we find that all supersymmetries are broken for
generic deformation parameter but part of supersymmetries are unbroken for
special case. We also find that classical vacua admit fuzzy sphere
configuration. In N=2 case we determine the deformed supersymmetries. We
rewrite the deformed Lagrangians in terms of N=1 superspace, where the
deformation is interpreted as that of coupling constants.Comment: v2: reference added, v3: published version in JHE
Comments on gluon 6-point scattering amplitudes in N=4 SYM at strong coupling
We use the AdS/CFT prescription of Alday and Maldacena \cite{am} to analyze
gluon 6-point scattering amplitudes at strong coupling in SYM. By
cutting and gluing we obtain AdS 6-point amplitudes that contain extra boundary
conditions and come close to matching the field theory results. We interpret
them as parts of the field theory amplitudes, containing only certain diagrams.
We also analyze the collinear limits of 6- and 5-point amplitudes and discuss
the results.Comment: 35 pages, 7 figures, latex, references adde
N=2 Supersymmetric U(1) Gauge Theory in Noncommutative Harmonic Superspace
We study N=2 supersymmetric U(1) gauge theory in the noncommutative harmonic
superspace with nonanticommutative fermionic coordinates. We examine the gauge
transformation which preserves the Wess-Zumino gauge by harmonic expansions of
component fields. The gauge transformation is shown to depend on the
deformation parameters and the anti-holomorphic scalar field. We compute the
action explicitly up to the third order in component fields and discuss the
field redefinitions so that the component fields transform canonically.Comment: 42 pages, LaTeX, v2: references added, v3: minor correction
RNA-seq analysis of the gonadal transcriptome during Alligator mississippiensis temperature-dependent sex determination and differentiation
Annotation of development-dependent dimorphic genes in gonad during Day 0â12. Annotation of development-dependent significantly up- and down- regulated DEGs at FDRâ<â0.01 in gonadal regions incubated under MPT and FPT conditions during Day 0 to Day 12. Ordered by decreasing fold change. (XLSX 196 kb
BPS Monopole Equation in Omega-background
We study deformed supersymmetries in N=2 super Yang-Mills theory in the
Omega-backgrounds characterized by two complex parameters . When one of the -parameters vanishes, the theory has
extended supersymmetries. We compute the central charge of the algebra and
obtain the deformed BPS monopole equation. We examine supersymmetries preserved
by the equation.Comment: 14 pages, typos corrected, published version in JHE
Non(anti)commutative N=(1,1/2) Supersymmetric U(1) Gauge Theory
We study a reduction of deformation parameters in non(anti)commutative N=2
harmonic superspace to those in non(anti)commutative N=1 superspace. By this
reduction we obtain the exact gauge and supersymmetry transformations in the
Wess-Zumino gauge of non(anti)commutative N=2 supersymmetric U(1) gauge theory
defined in the deformed harmonic superspace. We also find that the action with
the first order correction in the deformation parameter reduces to the one in
the N=1 superspace by some field redefinition. We construct deformed N=(1,1/2)
supersymmetry in N=2 supersymmetric U(1) gauge theory in non(anti)commutative
N=1 superspace.Comment: 30 pages, LaTeX, V2: a reference adde
N=2 Instanton Effective Action in Omega-background and D3/D(-1)-brane System in R-R Background
We study the relation between the ADHM construction of instantons in the
Omega-background and the fractional D3/D(-1)-branes at the orbifold singularity
of C \times C^2/Z_2 in Ramond-Ramond (R-R) 3-form field strength background. We
calculate disk amplitudes of open strings connecting the D3/D(-1)-branes in
certain R-R background to obtain the D(-1)-brane effective action deformed by
the R-R background. We show that the deformed D(-1)-brane effective action
agrees with the instanton effective action in the Omega-background.Comment: 35 pages, no figures, references adde
Thermodynamic Bethe Ansatz Equations for Minimal Surfaces in AdS_3
We study classical open string solutions with a null polygonal boundary in
AdS_3 in relation to gluon scattering amplitudes in N=4 super Yang-Mills at
strong coupling. We derive in full detail the set of integral equations
governing the decagonal and the dodecagonal solutions and identify them with
the thermodynamic Bethe ansatz equations of the homogeneous sine-Gordon models.
By evaluating the free energy in the conformal limit we compute the central
charges, from which we observe general correspondence between the polygonal
solutions in AdS_n and generalized parafermions.Comment: 25 pages, 4 figures, v2: a figure and references added, minor
corrections, v3: references added, minor corrections, to appear in JHE
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