1 | The first talk on “a loop space representation of quantum general relativity” was given at a conference in India in 1987 [264]. | |

2 | The relative size of the two communities can be estimated from the fact that there were 452 registered participants at the STRINGS 07 conference in Madrid, EU, and 156 at the LOOPS 07 conference in Morelia, Mexico. | |

3 | This situation might change with the data from the LHC, expected soon. | |

4 | For a discussion of this idea, see [256], [276] and [261]. | |

5 | I have heard the following criticism from a well-known high-energy physicist: “Loop gravity is certainly physically wrong because it is not supersymmetric, and because it is in four dimensions”. This is silly. For the moment the world still insists on looking four-dimensional and non-supersymmetric in all experiments. Science is to adapt our ideas to what we find in Nature; it is not to disbelieve Nature because we like our ideas. We must not mistake very interesting hypotheses (such as supersymmetry and higher dimensions) for established truths. | |

6 | Loop quantum gravity is an attempt to solve the last problem in Isham’s lectures [154]. | |

7 | Forty-two, of course, is The Answer… | |

8 | A general approach to this problem, and an idea about its connection with the “problem of time” in quantum gravity, have been developed in [250, 251, 90]. |

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