首页> 外文学位 >Renormalizable quantum field theories in the large-N limit.
【24h】

Renormalizable quantum field theories in the large-N limit.

机译:大N极限中的可重归一化量子场论。

获取原文
获取原文并翻译 | 示例

摘要

In this thesis, we study two examples of renormalizable quantum field theories in the large-N limit. Chapter one is a general introduction describing physical motivations for studying such theories.; In chapter two, we describe the large-N method in field theory and discuss the pioneering work of 't Hooft in large-N two-dimensional Quantum Chromodynamics (QCD). In chapter three we study a spherically symmetric approximation to four-dimensional QCD ('spherical QCD'). We recast spherical QCD into a bilocal (constrained) theory of hadrons which in the large-N limit is equivalent to large-N spherical QCD for all energy scales. The linear approximation to this theory gives an eigenvalue equation which is the analogue of the well-known 't Hooft's integral equation in two dimensions. This eigenvalue equation is a scale invariant one and therefore leads to divergences in the theory. We give a non-perturbative renormalization prescription to cure this and obtain a beta function which shows that large-N spherical QCD is asymptotically free.; In chapter four, we review the essentials of conformal field theories in two and higher dimensions, particularly in the context of critical phenomena. In chapter five, we study the O(N) non-linear sigma model on three-dimensional curved spaces in the large-N limit and show that there is a non-trivial ultraviolet stable critical point at which it becomes conformally invariant. We study this model at this critical point on examples of spaces of constant curvature and compute the mass gap in the theory, the free energy density (which turns out to be a universal function of the information contained in the geometry of the manifold) and the two-point correlation functions. The results we get give an indication that this model is an example of a three-dimensional analogue of a rational conformal field theory. A conclusion with a brief summary and remarks follows at the end.
机译:在本文中,我们研究了在大N极限下可重整化量子场论的两个例子。第一章是概述,介绍了研究此类理论的物理动机。在第二章中,我们描述了场论中的大N方法,并讨论了t Hooft在大N二维量子色动力学(QCD)中的开拓性工作。在第三章中,我们研究了对四维QCD(“球面QCD”)的球对称近似。我们将球面QCD重铸为强子的双局部(受约束)理论,在所有能量尺度下,在大N极限下等效于大N球QCD。对该理论的线性逼近给出了一个特征值方程,该特征值方程在二维上类似于众所周知的“ t Hooft”积分方程。该特征值方程是尺度不变的,因此导致理论上的分歧。我们给出了一个非扰动的重整化处方来治愈它,并获得一个beta函数,该函数表明大N球面QCD渐近自由。在第四章中,我们回顾了二维和更高维度的共形场理论的本质,特别是在关键现象的背景下。在第五章中,我们研究了在大N极限内的三维弯曲空间上的O(N)非线性sigma模型,并表明存在一个非平凡的紫外线稳定临界点,在该临界点上,它变为保形不变。我们在恒定曲率空间示例的关键点研究此模型,并从理论上计算质量差距,自由能密度(结果证明是歧管几何中包含的信息的通用函数)和两点相关函数。我们得到的结果表明,该模型是一个有理共形场理论的三维模拟示例。最后是一个带有简短总结和评论的结论。

著录项

  • 作者

    Guruswamy, Sathya.;

  • 作者单位

    University of Rochester.;

  • 授予单位 University of Rochester.;
  • 学科 Physics Elementary Particles and High Energy.
  • 学位 Ph.D.
  • 年度 1995
  • 页码 114 p.
  • 总页数 114
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 高能物理学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号