Maximum Principles for Null Hypersurfaces and Null Splitting Theorems
, 1999 A maximum principle for C^0 null hypersurfaces is obtained and used to derive a splitting theorem for spacetimes which contain null lines. As a consequence of this null splitting theorem, it is proved that an asymptotically simple vacuum (Ricci flat ...
Galloway, Gregory J.
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Anisotropic Null String Cosmologies [PDF]
, 1998 We study string propagation in an anisotropic, cosmological background. We solve the equations of motion and the constraints by performing a perturbative expansion of the string coordinates in powers of c^2, the world-sheet speed of light.
A. KUIROUKIDIS +9 more
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A Syntactic Analysis of Ergative Case Marking in some Iranian Languages: A minimalist View [PDF]
زبان پژوهی, 2019 Tatic-type languages are among west Iranian languages divided into four main groups: northern Tatic, central Tatic, southern Tatic and Taleshi group (Stilo, 1981, p. 139).
Ifa Shafai, Mohammad Dabirmoghaddam
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Schild's Null Strings in Flat and Curved Backgrounds [PDF]
, 1995 Schild's null (tensionless) strings are discussed in certain flat and curved backgrounds. We find closed, stationary, null strings as natural configurations existing on the horizons of spacetimes which possess such null hypersurfaces.
A. A. Zheltukhin +22 more
core +3 more sources
, 2014 We define and investigate a quantisation of null hypersurfaces in the context of loop quantum gravity on a fixed graph. The main tool we use is the parametrisation of the theory in terms of twistors, which has already proved useful in discussing the ...
Speziale, Simone, Zhang, Mingyi
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Assessment of causal relationships between teaching skills and students’ academic progress with the mediating role of positive and negative emotions and perceived control using the Structural Equation Modeling approach [PDF]
مطالعات روانشناسی تربیتی, 2018 The present study aimed to assess the causal relationships between teaching skills and students’ academic progress with the mediating role of positive and negative emotions and perceived control using the structural equation structural equation modeling ...
mostafa bagherian far +2 more
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Density Dependence of Transport Coefficients from Holographic Hydrodynamics
, 2008 We study the transport coefficients of Quark-Gluon-Plasma in finite temperature and finite baryon density. We use AdS/QCD of charged AdS black hole background with bulk-filling branes identifying the U(1) charge as the baryon number.
Ge, XH +5 more
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The effect of the curriculum integration approach on the academic achievement of fourth grade female students in Khash city [PDF]
مطالعات روانشناسی تربیتی, 2019 The purpose of this study was to investigate the effect of the curriculum integration approach on the academic achievement of fourth grade female students in Khash city. The research method is quasi-experimental.
tahere hashemnejad +2 more
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Sachs' free data in real connection variables [PDF]
, 2017 We discuss the Hamiltonian dynamics of general relativity with real connection variables on a null foliation, and use the Newman-Penrose formalism to shed light on the geometric meaning of the various constraints.
De Paoli, Elena, Speziale, Simone
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Psychosocial Intervention, 2019 Research has highlighted that drop-out from youth sport has emerged to become a global trend with drop-out rates exceeding 30% in some countries. This study aimed to investigate the effect of a change in perceived support on intentions to drop out from ...
David Lavallee +3 more
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