Muutke küpsiste eelistusi

Random Tensors [Kõva köide]

(Researcher, Centre de Physique Théorique, École Polytechnique, CNRS, Université Paris-Saclay, France)
  • Formaat: Hardback, 344 pages, kõrgus x laius x paksus: 247x176x23 mm, kaal: 814 g, 89
  • Ilmumisaeg: 06-Oct-2016
  • Kirjastus: Oxford University Press
  • ISBN-10: 0198787936
  • ISBN-13: 9780198787938
  • Formaat: Hardback, 344 pages, kõrgus x laius x paksus: 247x176x23 mm, kaal: 814 g, 89
  • Ilmumisaeg: 06-Oct-2016
  • Kirjastus: Oxford University Press
  • ISBN-10: 0198787936
  • ISBN-13: 9780198787938
Written by the creator of the modern theory of random tensors, this book is the first self-contained introductory text to this rapidly developing theory. Starting from notions familiar to the average researcher or PhD student in mathematical or theoretical physics, the book presents in detail the theory and its applications to physics.

The recent detections of the Higgs boson at the LHC and gravitational waves at LIGO mark new milestones in Physics confirming long standing predictions of Quantum Field Theory and General Relativity. These two experimental results only reinforce today the need to find an underlying common framework of the two: the elusive theory of Quantum Gravity.

Over the past thirty years, several alternatives have been proposed as theories of Quantum Gravity, chief among them String Theory. While these theories are yet to be tested experimentally, key lessons have already been learned. Whatever the theory of Quantum Gravity may be, it must incorporate random geometry in one form or another. This book introduces a framework for studying random geometries in any dimensions. Building on the resounding success of random matrices as theories of random two dimensional surfaces, random tensors are their natural generalization to theories of random geometry in arbitrary dimension. This book shows that many of the celebrated results in random matrices, most notably 't Hooft's 1/N expansion, can be generalized to higher dimensions. It provides a complete and self-contained derivation of the key results on random tensors.
1 Introduction
1(6)
I Toolbox for random tensors
7(136)
2 Preliminaries
9(18)
2.1 Tensors
9(3)
2.2 Invariants
12(8)
2.2.1 Edge colored graphs
14(3)
2.2.2 Matrices
17(3)
2.3 Connected and disconnected trace invariants
20(2)
2.4 Uniqueness of the decomposition on traceinvariants
22(2)
2.5 Invariant probability measures
24(3)
3 Generalities on edge colored graphs
27(22)
3.1 Faces, bubbles and the D-complex
27(2)
3.2 The dual triangulation
29(4)
3.3 Open graphs and the boundary graph
33(10)
3.3.1 The contraction of edges of color 0
37(4)
3.3.2 The composition of D-colored graphs
41(2)
3.4 Combinatorial maps and D-colored graphs
43(6)
3.4.1 Jackets of colored graphs
44(1)
3.4.2 The degree
45(4)
4 The classification of edge colored graphs
49(40)
4.1 Melonic graphs
49(6)
4.2 The melonic core
55(4)
4.3 Chains
59(4)
4.3.1 Classification of chains
61(2)
4.4 Schemes
63(3)
4.5 Schemes of fixed degree
66(15)
4.5.1 Proof of Proposition 4.1
67(12)
4.5.2 Proof of Proposition 4.2
79(2)
4.6 Exact enumeration
81(8)
4.6.1 Melonic graphs and cores
81(1)
4.6.2 Chains of (D -- 1)-dipoles and schemes
82(4)
4.6.3 The enumeration of rooted colored graph of fixed degree
86(3)
5 Melonic graphs
89(30)
5.1 Quartic melonic graphs
90(2)
5.2 Melonic graphs and colored, rooted, (D + 1)-ary trees
92(2)
5.3 The melonic balls
94(1)
5.4 Random melons and branched polymers
95(24)
5.4.1 The Hausdorff dimension
97(10)
5.4.2 The spectral dimension
107(12)
6 The universality theorem
119(24)
6.1 Random matrices
120(6)
6.1.1 Gaussian distribution of a random matrix
120(3)
6.1.2 Invariant probability measures for random matrices
123(3)
6.2 Gaussian distribution for tensors
126(6)
6.2.1 Uniqueness of the normalization
130(2)
6.3 Trace invariant tensor measures
132(11)
6.3.1 Universality for random tensors
135(4)
6.3.2 Nonuniform scalings
139(4)
II Random tensor models
143(144)
7 A digest of matrix models
145(10)
7.1 Invariant matrix models
145(1)
7.2 The 1/N expansion and the large N limit
146(6)
7.2.1 The Feynman expansion
146(3)
7.2.2 The 1/N expansion
149(1)
7.2.3 The continuum limit
150(2)
7.3 The Schwinger-Dyson equations
152(3)
7.3.1 Graphical interpretation
152(1)
7.3.2 Algebra of constraints
153(2)
8 The perturbative expansion of tensor models
155(20)
8.1 Invariant probability measures revisited
155(1)
8.2 The 1/N expansion of tensor models
156(4)
8.2.1 The expectations of invariants
159(1)
8.3 Proper uniform boundedness
160(3)
8.3.1 Feynman graphs for cumulants
160(2)
8.3.2 Perturbative bounds
162(1)
8.4 The large N limit
163(3)
8.5 The continuum limit
166(2)
8.6 The algebra of constraints
168(7)
8.6.1 A Lie Algebra Indexed by Observables
168(2)
8.6.2 Schwinger-Dyson equations
170(5)
9 The quartic tensor model
175(50)
9.1 The quartic models
175(3)
9.1.1 Feynman graphs
176(2)
9.2 Edge multicolored maps
178(13)
9.2.1 Maps with p and r edges
183(8)
9.3 The intermediate field representation
191(7)
9.3.1 Feynman graphs for the intermediate field
193(2)
9.3.2 The perturbative 1/N expansion
195(1)
9.3.3 Perturbative uniform boundedness
196(2)
9.4 The constructive expansions
198(9)
9.4.1 The loop vertex expansion
198(6)
9.4.2 The mixed expansion
204(3)
9.5 Non perturbative tensor models
207(18)
9.5.1 The melonic models
207(10)
9.5.2 Summary of non perturbative results
217(3)
9.5.3 The generic quartic model
220(5)
10 The double scaling limit
225(38)
10.1 The continuum limit as a phase transition
225(2)
10.2 The melonic phase revisited
227(21)
10.2.1 Translating the intermediate field
230(4)
10.2.2 Feynman rules
234(8)
10.2.3 Translating to the vacuum
242(2)
10.2.4 The 1/N expansion for the fluctuation field
244(2)
10.2.5 The first nontrivial order
246(2)
10.3 Double scaling
248(15)
10.3.1 Enhancement at criticality
248(1)
10.3.2 Maximal number of broken edges
249(1)
10.3.3 Cumulants
250(6)
10.3.4 Critical dimension
256(1)
10.3.5 Explicit computations
257(6)
11 Symmetry breaking
263(16)
11.1 The melonic model with only one interaction
264(3)
11.2 Integrating out the massless modes
267(2)
11.2.1 Block diagonalization
267(1)
11.2.2 Jacobian
267(2)
11.3 The effective theory
269(4)
11.3.1 Feynman graphs
270(3)
11.4 The phases of the model and their geometry
273(6)
11.4.1 The matrix case D = 2
274(1)
11.4.2 The tensor case D ≥ 3
275(4)
12 Conclusions
279(8)
III Appendices
287(32)
A The Weingarten functions revisited
289(6)
A.1 Generating function
290(2)
A.2 Schwinger--Dyson equations
292(3)
B Probability measures
295(12)
B.1 Gaussian measures
296(2)
B.1.1 Feynman graphs
298(1)
B.1.2 Properties of the Gaussian measure
299(2)
B.2 Perturbed Gaussian measures
301(1)
B.2.1 Quadratic perturbation
302(1)
B.2.2 Generic perturbation
303(4)
C Borel summability
307(4)
D The BKAR formula
311(8)
D.1 The forest formula and the connected moments
315(1)
D.2 Hepp sectors
316(3)
Bibliography 319(12)
Index 331
Rzvan Gheorghe Guru studied as an undergraduate at the Physics Department of the University of Bucharest before coming to France in 2002 as an élève of the École Normale Supérieure de Paris, Selection Internationale. He obtained his BA and MA degrees from the ENS and continued with a PhD in Mathematical Physics at the Université Paris 11, graduating in 2008. From 2008 to 2012 he was a postdoctoral researcher and a senior postdoctoral researcher at the Perimeter Institute for Theoretical Physics. In 2012 he joined the Centre National de la Recherche Scientifique as a full-time researcher and obtained his Habilitation a diriger des recherches in 2015.