22530691
Yang-Mills origin of gravitational symmetries.
By regarding gravity as the convolution of left and right Yang-Mills theories together with a spectator scalar field in the biadjoint representation, we derive in linearized approximation, the gravitational symmetries of general covariance, p-form gauge invariance, local Lorentz invariance, and local supersymmetry from the flat space Yang-Mills symmetries of local gauge invariance and global super-Poincaré symmetry. As a concrete example, we focus on the new minimal (12+12) off shell version of simple four-dimensional supergravity obtained by tensoring the off shell Yang-Mills multiplets (4+4, N_{L}=1) and (3+0, N_{R}=0).
119108302
Chiral squaring
A bstractWe construct the states and symmetries of N$$ \mathcal{N} $$ = 4 super-Yang-Mills by tensoring two N$$ \mathcal{N} $$ = 1 chiral multiplets and introducing two extra SUSY generators. This allows us to write the maximal N$$ \mathcal{N} $$ = 8 supergravity as four copies of the chiral multiplet. We extend this to higher dimensions and discuss applications to scattering amplitudes.
26765894
Magic square from Yang-Mills squared.
We give a unified description of D=3 super-Yang-Mills theory with N=1, 2, 4, and 8 supersymmeties in terms of the four division algebras: reals (R), complexes (C), quaternions (H) and octonions (O). Tensoring left and right super-Yang-Mills multiplets with N=1, 2, 4, 8 we obtain a magic square RR, CR, CC, HR, HC, HH, OR, OC, OH, OO description of D=3 supergravity with N=2, 3, 4, 5, 6, 8, 9, 10, 12, 16.
53550841
An octonionic formulation of the M-theory algebra
A bstractWe give an octonionic formulation of the N=1$$ \mathcal{N}=1 $$ supersymmetry algebra in D = 11, including all brane charges. We write this interms of a novel outer product, which takes a pair of elements of the division algebra A$$ \mathbb{A} $$ and returns a real linear operator on A$$ \mathbb{A} $$. More generally, with this product comes the power to rewrite any linear operation on ℝn$$ {\mathbb{R}}^n $$ (n =1, 2, 4, 8) in terms of multiplication in the n-dimensional division algebra A$$ \mathbb{A} $$. Finally, we consider the reinterpretation of the D =11 supersymmetry algebra as an octonionic algebra in D =4 and the truncation to division subalgebras.
5513253
A HST/WFC3-IR Morphological Survey of Galaxies at z = 1.5-3.6. II. The Relation between Morphology and Gas-phase Kinematics
We analyze rest-frame optical morphologies and gas-phase kinematics as traced by rest-frame far-UV and optical spectra for a sample of 204 star-forming galaxies in the redshift range z ~ 2-3 drawn from the Keck Baryonic Structure Survey. We find that spectroscopic properties and gas-phase kinematics are closely linked to morphology: compact galaxies with semimajor axis radii r ≾ 2 kpc are substantially more likely than their larger counterparts to exhibit Lyα in emission. Although Lyα emission strength varies widely within galaxies of a given morphological type, all but one of 19 galaxies with Lyα equivalent width W_(Lyα) > 20 A have compact and/or multiple-component morphologies with r ≤ 2.5 kpc. The velocity structure of absorption lines in the galactic continuum spectra also varies as a function of morphology. Galaxies of all morphological types drive similarly strong outflows (as traced by the blue wing of interstellar absorption line features), but the outflows of larger galaxies are less highly ionized and exhibit larger optical depth at the systemic redshift that may correspond to a decreasing efficiency of feedback in evacuating gas from the galaxy. This v ~ 0 km s^(–1) gas is responsible both for shifting the mean absorption line redshift and attenuating W_(Lyα) (via a longer resonant scattering path) in galaxies with larger rest-optical half-light radii. In contrast to galaxies at lower redshifts, there is no evidence for a correlation between outflow velocity and inclination, suggesting that outflows from these puffy and irregular systems may be poorly collimated. Our observations are broadly consistent with theoretical models of inside-out growth of galaxies in the young universe, in which typical z ~ 2-3 star-forming galaxies are predominantly unstable, dispersion-dominated, systems fueled by rapid gas accretion that later form extended rotationally supported disks when stabilized by a sufficiently massive stellar component.
36063309
THE MASS-RADIUS RELATION FOR STAR-FORMING GALAXIES AT z ∼ 1.5-3.0
We present early results from a Hubble Space Telescope WFC3/IR imaging survey of star-forming galaxies in the redshift range 1.5 < z < 3.0. When complete, this survey will consist of 42 orbits of F160W imaging distributed amongst 10 survey fields on the line of sight to bright background QSOs, covering 65 arcmin^2 to a depth of 27.9 AB with a point-spread function FWHM of 0".18. In this contribution, we use a subset of these fields to explore the evolution of the galactic stellar mass-radius relation for a magnitude-limited sample of 102 spectroscopically confirmed star-forming galaxies ((SFR) ~ 30 M_☉ yr^(–1)) with stellar mass M_* ~ 10^(10) M_☉. Although the light profile of these galaxies often has an irregular, multi-component morphology, it is typically possible to describe the brightest component with a Sersic profile of index n ~ 1. The circularized half-light radius r e of the brightest component is on average r_e = 1.66 ± 0.79 kpc (i.e., ~50%-70% the size of local late-type galaxies with similar stellar mass), consistent with recent theoretical models that incorporate strong feedback from star-forming regions. The mean half-light radius increases with stellar mass and, at fixed stellar mass, evolves with cosmic time as ~(1 + z)^(–1.42), suggesting that high-redshift star-forming galaxies may evolve onto the local stellar mass-radius relation by redshift z ~ 1.
119203296
Degeneracy induced scaling of the correlation length for periodic models
Abstract The broken symmetric phase of scalar models exhibits an infrared fixed point which is induced by the degenerate effective potential. The definition of the correlation length in the infrared regime enables us to determine the type of the phase transition in the model. It is shown that the massive sine-Gordon model exhibits a continuous, while the layered sine-Gordon model has an infinite order Kosterlitz–Thouless type phase transition.
11500580
Renormalization-group analysis of layered sine-Gordon type models
Abstract We analyze the phase structure and the renormalization group (RG) flow of the generalized sine-Gordon models with nonvanishing mass terms, using the Wegner–Houghton RG method in the local potential approximation. Particular emphasis is laid upon the layered sine-Gordon (LSG) model, which is the bosonized version of the multi-flavour Schwinger model and approaches the sum of two “normal”, massless sine-Gordon (SG) models in the limit of a vanishing interlayer coupling J . Another model of interest is the massive sine-Gordon (MSG) model. The leading-order approximation to the UV (ultraviolet) RG flow predicts two phases for the LSG as well as for the MSG, just as it would be expected for the SG model, where the two phases are known to be separated by the Coleman fixed point. The presence of finite mass terms (for the LSG and the MSG) leads to corrections to the UV RG flow, which are naturally identified as the “mass corrections”. The leading-order mass corrections are shown to have the following consequences: (i) for the MSG model, only one phase persists, and (ii) for the LSG model, the transition temperature is modified. Within the mass-corrected UV scaling laws, the limit of J → 0 is thus nonuniform with respect to the phase structure of the model. The modified phase structure of general massive sine-Gordon models is connected with the breaking of symmetries in the internal space spanned by the field variables. For the LSG, the second-order subleading mass corrections suggest that there exists a cross-over regime before the IR scaling sets in, and the nonlinear terms show explicitly that higher-order Fourier modes appear in the periodic blocked potential.
119181705
AN HST/WFC3-IR MORPHOLOGICAL SURVEY OF GALAXIES AT z = 1.5-3.6. I. SURVEY DESCRIPTION AND MORPHOLOGICAL PROPERTIES OF STAR-FORMING GALAXIES*
We present the results of a 42-orbit Hubble Space Telescope Wide-Field Camera 3 (HST/WFC3) survey of the rest-frame optical morphologies of star-forming galaxies with spectroscopic redshifts in the range z = 1.5-3.6. The survey consists of 42 orbits of F160W imaging covering ~65 arcmin2 distributed widely across the sky and reaching a depth of 27.9 AB for a 5σ detection within a 0.2 arcsec radius aperture. Focusing on an optically selected sample of 306 star-forming galaxies with stellar masses in the range M_* = 10^9-10^(11) M_☉, we find that typical circularized effective half-light radii range from ~0.7 to 3.0 kpc and describe a stellar mass-radius relation as early as z ~ 3. While these galaxies are best described by an exponential surface brightness profile (Sersic index n ~ 1), their distribution of axis ratios is strongly inconsistent with a population of inclined exponential disks and is better reproduced by triaxial stellar systems with minor/major and intermediate/major axis ratios ~0.3 and 0.7, respectively. While rest-UV and rest-optical morphologies are generally similar for a subset of galaxies with HST/Advanced Camera for Surveys imaging data, differences are more pronounced at higher masses M_* > 3 × 10^(10) M_☉. Finally, we discuss galaxy morphology in the context of efforts to constrain the merger fraction, finding that morphologically identified mergers/non-mergers generally have insignificant differences in terms of physical observables such as stellar mass and star formation rate, although merger-like galaxies selected according to some criteria have statistically smaller effective radii and correspondingly larger Σ_(SFR).