17,180 research outputs found
Chiral Symmetry and Scalars
The suggestion by Jaffe that if is a light state
then even the fundamental chiral transformation properties of the
becomes {\bf unclear}, has stimulated much interest. Adler pointed out
that in fact the seminal work on chiral symmetry via PCAC consistency, is
really quite consistent with the being predominantly
. This interpretation was actually backed by subsequent work
on effective Lagrangian methods for linear and non linear realizations. More
recent work of Achasov suggests that intermediate four-quark states determine
amplitudes involving other scalars and below 1 GeV,
and the report by Ning Wu that study on meson in continue to support a non with mass
as low as 390 MeV. It is also noted that more recent re-analysis of
scattering by S. Ishida {\em et al.} together with the work of the E791
Collaboration, support the existence of the scalar particle with
comparatively light mass as well.Comment: 4 pages, aipproc style file. Parallel session talk at Hadron
2001-Protvin
Kartul mahe- ja tavaviljeluse süsteemide võrdluskatses aastatel 2008-2012
Kartul on üheks armastatumaiks kultuuriks nii meil kui maalimas. Kartulit on läbi aegade peetud teiseks „leivaks“ ning tänapäeval ei kujutaks meist keegi ette oma toidulauda, kui sealt puuduks toidukartul. Maheviljelus on Eestis aasta-aastalt laienenud on mahekartulikasvatuse pindala siiski iga aastaga vähenenud. Uurimistöö eesmärk oli uurida kuidas erinevad viljelusviisid mõjutavad mugulate saagistruktuuri elemente ning kui suurt mõju avaldab see saagi kvaliteedile
Algebraic dependence of commuting elements in algebras
The aim of this paper to draw attention to several aspects of the algebraic
dependence in algebras. The article starts with discussions of the algebraic
dependence problem in commutative algebras. Then the Burchnall-Chaundy
construction for proving algebraic dependence and obtaining the corresponding
algebraic curves for commuting differential operators in the Heisenberg algebra
is reviewed. Next some old and new results on algebraic dependence of commuting
q-difference operators and elements in q-deformed Heisenberg algebras are
reviewed. The main ideas and essence of two proofs of this are reviewed and
compared. One is the algorithmic dimension growth existence proof. The other is
the recent proof extending the Burchnall-Chaundy approach from differential
operators and the Heisenberg algebra to the q-deformed Heisenberg algebra,
showing that the Burchnall-Chaundy eliminant construction indeed provides
annihilating curves for commuting elements in the q-deformed Heisenberg
algebras for q not a root of unity.Comment: LaTeX, 14 pages, no figure
On the cohomology of Artin groups in local systems and the associated Milnor fiber
Let W be a finite irreducible Coxeter group and let X_W be the classifying
space for G_W, the associated Artin group. If A is a commutative unitary ring,
we consider the two local systems L_q and L_q' over X_W, respectively over the
modules A[q,q^{-1}] and A[[q,q^{-1}]], given by sending each standard generator
of G_W into the automorphism given by the multiplication by q. We show that
H^*(X_W,L_q') = H^{*+1}(X_W,L_q) and we generalize this relation to a
particular class of algebraic complexes. We remark that H^*(X_W,L_q') is equal
to the cohomology with trivial coefficients A of the Milnor fiber of the
discriminant bundle of the associated reflection group.Comment: 9 page
Resume: LI Ning
This resume is composed both in Chinese and English (incomplete translation). (Jerry Wu\u2723).https://digital.kenyon.edu/zhoudocs/1137/thumbnail.jp
Material Limitations on the Detection Limit in Refractometry
We discuss the detection limit for refractometric sensors relying on high-Q
optical cavities and show that the ultimate classical detection limit is given
by min{Dn} > eta with n+i*eta being the complex refractive index of the
material under refractometric investigation. Taking finite Q factors and
filling fractions into account, the detection limit declines. As an example we
discuss the fundamental limits of silicon-based high-Q resonators, such as
photonic crystal resonators, for sensing in a bio-liquid environment, such as a
water buffer. In the transparency window of silicon the detection limit becomes
almost independent on the filling fraction, while in the visible, the detection
limit depends strongly on the filling fraction because silicon absorbs
strongly.Comment: Published in Special Issue "Laser Spectroscopy and Sensing", Edited
by Prof. M.W. Sigris
What Are People Asking About COVID-19? A Question Classification Dataset
We present COVID-Q, a set of 1,690 questions about COVID-19 from 13 sources,
which we annotate into 15 question categories and 207 question clusters. The
most common questions in our dataset asked about transmission, prevention, and
societal effects of COVID, and we found that many questions that appeared in
multiple sources were not answered by any FAQ websites of reputable
organizations such as the CDC and FDA. We post our dataset publicly at
https://github.com/JerryWei03/COVID-Q. For classifying questions into 15
categories, a BERT baseline scored 58.1% accuracy when trained on 20 examples
per category, and for a question clustering task, a BERT + triplet loss
baseline achieved 49.5% accuracy. We hope COVID-Q can help either for direct
use in developing applied systems or as a domain-specific resource for model
evaluation.Comment: Published in Proceedings of the 1st Workshop on NLP for COVID-19 at
ACL 202
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