Results 41 to 50 of about 28,455,638 (326)

Winding Number in String Field Theory

, 2011
Motivated by the similarity between cubic string field theory (CSFT) and the Chern-Simons theory in three dimensions, we study the possibility of interpreting N=(\pi^2/3)\int(U Q_B U^{-1})^3 as a kind of winding number in CSFT taking quantized values. In
E Witten, Hiroyuki Hata, M Murata, M Schnabl, T Erler, T Erler, T Takahashi, Toshiko Kojita, Y Okawa   +8 more
core   +1 more source

The Dependence of Dynamo $\alpha$-Effect on Reynolds Numbers, Magnetic Prandtl Number, and the Statistics of MHD Turbulence [PDF]

, 2001
We generalize the derivation of dynamo coefficient $\alpha$ of Field et al (1999) to include the following two aspects: first, the de-correlation times of velocity field and magnetic field are different; second, the magnetic Prandtl number can be ...
Gruzinov A., Hongsong Chou, Piddington J. H., Piddington J. H., Piddington J. H., Piddington J. H., Piddington J. H., Roberts P. H., Zeldovich Ya. B.   +8 more
core   +2 more sources

A universal first order formula defining the ring of integers in a number field [PDF]

, 2012
We show that the complement of the ring of integers in a number field K is Diophantine. This means the set of ring of integers in K can be written as {t in K | for all x_1, ..., x_N in K, f(t,x_1, ..., x_N) is not 0}.
Jennifer Park
semanticscholar   +1 more source

Zero-Field Skyrmions with a High Topological Number in Itinerant Magnets. [PDF]

Physical Review Letters, 2017
Magnetic Skyrmions are swirling spin textures with topologically protected noncoplanarity. Recently, Skyrmions with the topological number of unity have been extensively studied in both experiment and theory.
Ryo Ozawa, S. Hayami, Y. Motome
semanticscholar   +1 more source

Velocity field in a high prandtl number liquid bridge

MATEC Web of Conferences, 2015
A numerical model is developed to investigate the velocity fields of high prandtl number liquid bridge with surface deformation under microgravity. The Navier-Stokes equations coupled with the energy conservation equation are solved on a staggered grid ...
Yang Shuo, Liang Ruquan, He Jicheng
doaj   +1 more source

Lower bounds on the class number of algebraic function fields defined over any finite field [PDF]

, 2011
We give lower bounds on the number of effective divisors of degree $\leq g-1$ with respect to the number of places of certain degrees of an algebraic function field of genus $g$ defined over a finite field.
Ballet, Stéphane, Rolland, Robert
core   +2 more sources

Enumerating number fields [PDF]

Annals of Mathematics, 2020
We construct small models of number fields and deduce a better bound for the number of number fields of given degree and bounded discriminant.
openaire   +2 more sources

PAC fields over number fields [PDF]

Journal de théorie des nombres de Bordeaux, 2008
We prove that if K is a number field and N is a Galois extension of ℚ which is not algebraically closed, then N is not PAC over K.
openaire   +2 more sources

Computing quadratic subfields of number fields

Journal of Computational Algebra
Given a number field, it is an important question in algorithmic number theory to determine all its subfields. If the search is restricted to abelian subfields, we can try to determine them by using class field theory.
Andreas-Stephan Elsenhans, Jürgen Klüners   +1 more
doaj   +1 more source

Effects of Regional Magnetic Field on Rotating MHD Flow Field of Unity Magnetic Prandtl Number

Journal of Applied Mathematics, 2012
This work numerically studies the flow pattern of a magnetic fluid filled within an annulus whose inner cylinder is moving at a constant rotational speed, while the outer cylinder is stationary but under the influence of a nonuniform external magnetic ...
Sheng Lun Hung, Jik Chang Leong
doaj   +1 more source