کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1842699 1031480 2006 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Taming the cosmological constant in 2D causal quantum gravity with topology change
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات فیزیک ریاضی
پیش نمایش صفحه اول مقاله
Taming the cosmological constant in 2D causal quantum gravity with topology change
چکیده انگلیسی
As shown in previous work, there is a well-defined nonperturbative gravitational path integral including an explicit sum over topologies in the setting of causal dynamical triangulations in two dimensions. In this paper we derive a complete analytical solution of the quantum continuum dynamics of this model, obtained uniquely by means of a double-scaling limit. We show that the presence of infinitesimal wormholes leads to a decrease in the effective cosmological constant, reminiscent of the suppression mechanism considered by Coleman and others in the four-dimensional Euclidean path integral. Remarkably, in the continuum limit we obtain a finite spacetime density of microscopic wormholes without assuming fundamental discreteness. This shows that one can in principle make sense of a gravitational path integral which includes a sum over topologies, provided suitable causality restrictions are imposed on the path integral histories.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Nuclear Physics B - Volume 751, Issue 3, 11 September 2006, Pages 419-435
نویسندگان
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