Approaches to Quantum Gravity

Index 583emergent, 99, 109, 163, 178, 184, 230, 329, 559,566, 571foam, 434, 437foliation, 49, 54, 57, 69, 70, 75–78, 80, 81, 140,155, 195, 244, 253, 279, 332, 345–347, 414,418fractal, 124, 125fuzziness, 205, 434, 437, 439non-commutative, 301, 302, 431, 432, 437, 443,444, 466, 467, 469, 473, 476, 477, 484–487,489, 491, 500, 504, 510, 514, 529, 572, 574quantum, 5, 10, 88, 206, 262, 264, 284relational, 97, 151singularities, 249, 253, 403, 555, 566superpositions of, 5, 99, 104, 129, 148spin foam models, 8–10, 56, 129, 136, 137, 140, 141,147, 153, 156, 248, 254, 255, 265, 267–270,272, 275, 276, 279–288, 290, 300, 306, 308,310, 316, 317, 320–322, 324–326, 328, 329,364, 374, 379, 402, 403, 509, 549, 559, 566,570, 576–579spin foams, 56, 129, 136, 139–141, 147, 255, 265,267, 269, 270, 272, 275, 276, 279–287, 290,300, 306, 316, 317, 322, 329, 379, 403spin networks, 28, 139–141, 255, 259, 260, 263–267,269, 270, 278–282, 284, 285, 290, 293, 313,316, 317, 319, 325, 326, 332, 549, 550,552–554, 561–563, 566, 567, 579standard model, 3, 8, 13, 14, 17, 90, 116, 123, 146,162, 196, 231, 248, 400, 436, 451, 530, 532,534–536, 542, 543, 562, 567string field theory, 211–214, 216–226, 232string theory, 4, 6, 8–10, 15, 17, 22, 99, 129, 137, 150,169, 172–176, 178, 179, 181–184, 187, 188,190, 195, 199, 205, 207, 210–213, 217, 223,224, 226, 229–232, 236, 343, 344, 430, 431,435–437, 439, 528, 538, 572duality, 182, 195landscape, 22, 210, 211, 213, 218, 225, 226, 230non-perturbative, 9, 213, 216, 222perturbative, 9, 14, 211, 212, 215, 221strings, 8, 10, 84, 173, 174, 178, 181, 188, 210–213,215, 217, 220, 221, 223–225, 230, 232, 324supergravity, 171–174, 177, 180–182, 205, 206, 552,553, 572superspace, 64, 310, 311, 323, 327midi-, 47, 63mini-, 47, 63, 80supersymmetry, 170–173, 177, 181–183, 187–189,193, 199, 204–207, 211, 217, 220, 223, 231,232, 248, 435, 538, 539symmetryasymptotic, 64, 178, 193conformal, 15, 173, 181, 183, 362CPT, 40, 434, 437–439, 481, 528diffeomorphism, 24, 178, 236, 245, 293, 295, 389,420, 512emergent, 24, 144, 539, 559, 560gauge, 13, 179, 180, 220, 263, 272, 276, 285, 291,293, 294, 312, 316, 320, 322, 370, 382, 389,530, 552, 558emergent, 178local, 96Lorentz, 153, 256, 270, 400, 402, 428, 433, 436,437, 440, 444, 445, 447, 500, 501, 529, 535,536, 538Poincaré, 158, 171, 304, 428, 433, 434, 436–438,440, 442, 500, 503, 510, 529tensor models, 320, 321timearrow, 198, 199background, 99, 103, 104, 106, 109, 144, 157cosmic, 126discrete, 16, 18, 109discretization, 194in history formalism, 70, 72–74, 78multifingered, 140, 242ordering, 78pre-geometric, 144problem of, 6, 7, 46, 54, 80, 108–110, 148, 191,194, 242, 243, 273, 386, 393, 406in classical GR, 7in quantum gravity, 7, 14translations, 74, 172topological defects, 18topological field theory, 15, 18, 254, 267, 268, 275,286–288, 292, 310, 496, 552, 553, 555, 556,558, 577topological gravity, 15, 324topologychange, 155, 160, 178, 195, 230, 290, 310, 311,318, 323, 332, 343, 345, 374, 400, 417, 418sum over-, 317, 321, 324, 325, 343, 369,417–419topos theory, 85, 87, 88, 91, 95, 97, 150cosmoi, 89twistor theory, 65, 70unification, 123, 427, 548, 549, 561, 562, 567unitarity, 14, 20, 40, 125, 142, 207, 379, 387, 388,391, 419universality, 100, 101, 104, 373, 414, 417Wheeler–deWitt equation, 6Wick rotation, 39, 41, 347, 403Wilson loop, 174, 180, 259, 278, 357,552–554