منابع مشابه
When bottom-up meets top-down.
Studying the intriguing question of how words or pictures are encoded, processed and stored has been a long-standing problem in cognition. Both the written word frog, and a picture of the animal, can lead to an observer to say /frog/, or otherwise to the association that frogs leap, croak, need water, etc. Two different types of account have been formulated to explain word and picture processin...
متن کاملHeterotic Cosmic Strings
We show that all three conditions for the cosmological relevance of heterotic cosmic strings, the right tension, stability and a production mechanism at the end of inflation, can be met in the strongly coupled M-theory regime. Whereas cosmic strings generated from weakly coupled heterotic strings have the well known problems posed by Witten in 1985, we show that strings arising from M5-branes w...
متن کاملOpen Heterotic Strings
We classify potential cosmic strings according to the topological charge measurable outside the string core. We conjecture that in string theory it is this charge that governs the stability of long strings. This would imply that the SO(32) heterotic string can have endpoints, but not the E8 × E8 heterotic string. We give various arguments in support of this conclusion. 1 Stability of cosmic str...
متن کاملHeterotic Strings with Torsion
In this paper we describe the heterotic dual of the type IIB theory compactified to four dimensions on a toroidal orientifold in the presence of fluxes. The type IIB background is most easily described in terms of an M-theory compactification on a four-fold. The heterotic dual is obtained by performing a series of U -dualities. We argue that these dualities preserve supersymmetry and that the s...
متن کاملHeterotic Vortex Strings
We determine the low-energy N = (0, 2) worldsheet dynamics of vortex strings in a large class of non-Abelian N = 1 supersymmetric gauge theories.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Fortschritte der Physik
سال: 2005
ISSN: 0015-8208,1521-3978
DOI: 10.1002/prop.200410205