870 research outputs found
Letter from Representative Burdick to Mr. H. J. Goddard Regarding Garrison Dam Pool Level, May 9, 1955
This letter, dated May 9, 1955 from United States Representative Usher Burdick to Mr. H. J. Goddard, publisher of the Dickey County Leader, of Ellendale, North Dakota, thanks Goddard for the professional way the Garrison Dam reservoir poll level issue was handled in the May 5 issue of the Leader.
See also:
Letter from H. J. Goddard to Representative Burdick Regarding Garrison Dam Pool Level, June 9, 1955https://commons.und.edu/burdick-papers/1293/thumbnail.jp
Letter from H. J. Goddard to Representative Burdick Regarding Garrison Dam Pool Level, June 9, 1955
This letter, dated June 9, 1955, from H. J. Goddard, publisher of the Dickey County Leader of Ellendale, North Dakota to United States (US) Representative Usher Burdick thanks Burdick for his recent letter and kind words regarding the Leader\u27s handling of the Garrison Reservoir pool level issue. Goddard notes that credit should go to Goddard\u27s son, Malcolm, a recent journalism graduate from the University of North Dakota. Goddard writes that he believes Burdick is correct about the dam\u27s pool level and adds that he does not approve of asking officials to weigh in on the topic when they do not know enough about it.
See also:
Letter from Representative Burdick to Mr. H. J. Goddard Regarding Garrison Dam Pool Level, May 9, 1955https://commons.und.edu/burdick-papers/1294/thumbnail.jp
On the coset duals of extended higher spin theories
We study the holographic duality between the M x M matrix extension of
Vasiliev higher spin theories on AdS3 and the large N limit of SU(N+M)/SU(N) x
U(1) type cosets. We present a simplified proof for the agreement of the
spectra and clarify the relation between this duality and the version in which
the cosets are replaced by Kazama-Suzuki models of Grassmannian type.Comment: 27 pages, 1 tabl
The Primary Spin-4 Casimir Operators in the Holographic SO(N) Coset Minimal Models
Starting from SO(N) current algebra, we construct two lowest primary higher
spin-4 Casimir operators which are quartic in spin-1 fields. For N is odd, one
of them corresponds to the current in the WB_{\frac{N-1}{2}} minimal model. For
N is even, the other corresponds to the current in the WD_{\frac{N}{2}} minimal
model. These primary higher spin currents, the generators of wedge subalgebra,
are obtained from the operator product expansion of fermionic (or bosonic)
primary spin-N/2 field with itself in each minimal model respectively. We
obtain, indirectly, the three-point functions with two real scalars, in the
large N 't Hooft limit, for all values of the 't Hooft coupling which should be
dual to the three-point functions in the higher spin AdS_3 gravity with matter.Comment: 65 pages; present the main results only and to appear in JHEP where
one can see the Appendi
The Coset Spin-4 Casimir Operator and Its Three-Point Functions with Scalars
We find the GKO coset construction of the dimension 4 Casimir operator that
contains the quartic WZW currents contracted with completely symmetric SU(N)
invariant tensors of ranks 4, 3, and 2. The requirements, that the operator
product expansion with the diagonal current is regular and it should be primary
under the coset Virasoro generator of dimension 2, fix all the coefficients in
spin-4 current, up to two unknown coefficients. The operator product expansion
of coset primary spin-3 field with itself fixes them completely. We compute the
three-point functions with scalars for all values of the 't Hooft coupling in
the large N limit. At fixed 't Hooft coupling, these three-point functions are
dual to that found by Chang and Yin recently in the undeformed AdS_3 bulk
theory (higher spin gravity with matter).Comment: 65 pages; the ambiguity for the two coefficient functions is
clarified and the abstract, the introduction, the subsection 3.4 and the
conclusion are improved and to appear in JHE
Supersymmetric holography on AdS3
The proposed duality between Vasiliev's supersymmetric higher spin theory on
AdS3 and the 't Hooft limit of the 2d superconformal Kazama-Suzuki models is
analysed in detail. In particular, we show that the partition functions of the
two theories agree in the large N limit.Comment: 25 pages, 3 figures, improved fig.
Limits of minimal models and continuous orbifolds
The lambda=0 't Hooft limit of the 2d W_N minimal models is shown to be
equivalent to the singlet sector of a free boson theory, thus paralleling
exactly the structure of the free theory in the Klebanov-Polyakov proposal. In
2d, the singlet sector does not describe a consistent theory by itself since
the corresponding partition function is not modular invariant. However, it can
be interpreted as the untwisted sector of a continuous orbifold, and this point
of view suggests that it can be made consistent by adding in the appropriate
twisted sectors. We show that these twisted sectors account for the `light
states' that were not included in the original 't Hooft limit. We also show
that, for the Virasoro minimal models (N=2), the twisted sector of our orbifold
agrees precisely with the limit theory of Runkel & Watts. In particular, this
implies that our construction satisfies crossing symmetry.Comment: 33 pages; v2: minor improvements and references added, published
versio
Higher spin AdS_3 holography with extended supersymmetry
We propose a holographic duality between a higher spin AdS_3 gravity with
so(p) extended supersymmetry and a large N limit of a 2-dimensional
Grassmannian-like model with a specific critical level k=N and a non-diagonal
modular invariant. As evidence, we show the match of one-loop partition
functions. Moreover, we construct symmetry generators of the coset model for
low spins which are dual to gauge fields in the supergravity. Further, we
discuss a possible relation to superstring theory by noticing an N=3
supersymmetry of critical level model at finite k,N. In particular, we examine
BPS states and marginal deformations. Inspired by the supergravity side, we
also propose and test another large N CFT dual obtained as a Z_2 automorphism
truncation of a similar coset model, but at a non-critical level.Comment: 44 pages, published versio
Large N=4 Holography
The class of 2d minimal model CFTs with higher spin AdS3 duals is extended to
theories with large N=4 superconformal symmetry. We construct a higher spin
theory based on the global D(2,1|alpha) superalgebra, and propose a large N
family of cosets as a dual CFT description. We also indicate how a non-abelian
version of this Vasiliev higher spin theory might give an alternative
description of IIB string theory on an AdS3 x S3 x S3 x S1 background.Comment: 41 pages, LaTe
Molecular evolution: sex accelerates adaptation
An analysis confirms the long-standing theory that sex increases the rate of
adaptive evolution by accelerating the speed at which beneficial mutations sweep
through sexual, as opposed to asexual, populations
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