### Abstract

Introduction Although there is enormous uncertainty about the nature of Quantum Gravity (QG), one thing is quite certain: the commonly used ideas of space and time should break down at or before the Planck length is reached. For example, elementary scattering processes with a Planck-sized center-of-mass energy create large enough quantum fluctuations in the gravitational field that space-time can no longer be treated as a classical continuum. It is then natural to question the exactness of the Lorentz invariance (LI) that is pervasive in all more macroscopic theories. Exact LI requires that an object can be arbitrarily boosted. Since the corresponding Lorentz contractions involve arbitrarily small distances, there is an obvious tension with the expected breakdown of classical space-time at the Planck length. Indeed, quite general arguments are made that lead to violations of LI within the two most popular approaches towards QG: string theory and loop quantum gravity This has given added impetus to the established line of research dedicated to the investigation of ways in which fundamental symmetries, like LI or CPT, could be broken. It was realized that extremely precise tests could be made with a sensitivity appropriate to certain order of magnitude estimates of violations of LI.

Original language | English (US) |
---|---|

Title of host publication | Approaches to Quantum Gravity |

Subtitle of host publication | Toward a New Understanding of Space, Time and Matter |

Publisher | Cambridge University Press |

Pages | 528-547 |

Number of pages | 20 |

Volume | 9780521860451 |

ISBN (Electronic) | 9780511575549 |

ISBN (Print) | 9780521860451 |

DOIs | |

State | Published - Jan 1 2009 |

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### All Science Journal Classification (ASJC) codes

- Physics and Astronomy(all)

### Cite this

*Approaches to Quantum Gravity: Toward a New Understanding of Space, Time and Matter*(Vol. 9780521860451, pp. 528-547). Cambridge University Press. https://doi.org/10.1017/CBO9780511575549.032

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*Approaches to Quantum Gravity: Toward a New Understanding of Space, Time and Matter.*vol. 9780521860451, Cambridge University Press, pp. 528-547. https://doi.org/10.1017/CBO9780511575549.032

**Lorentz invariance violation and its role in Quantum Gravity phenomenology.** / Collins, John C.; Perez, A.; Sudarsky, D.

Research output: Chapter in Book/Report/Conference proceeding › Chapter

TY - CHAP

T1 - Lorentz invariance violation and its role in Quantum Gravity phenomenology

AU - Collins, John C.

AU - Perez, A.

AU - Sudarsky, D.

PY - 2009/1/1

Y1 - 2009/1/1

N2 - Introduction Although there is enormous uncertainty about the nature of Quantum Gravity (QG), one thing is quite certain: the commonly used ideas of space and time should break down at or before the Planck length is reached. For example, elementary scattering processes with a Planck-sized center-of-mass energy create large enough quantum fluctuations in the gravitational field that space-time can no longer be treated as a classical continuum. It is then natural to question the exactness of the Lorentz invariance (LI) that is pervasive in all more macroscopic theories. Exact LI requires that an object can be arbitrarily boosted. Since the corresponding Lorentz contractions involve arbitrarily small distances, there is an obvious tension with the expected breakdown of classical space-time at the Planck length. Indeed, quite general arguments are made that lead to violations of LI within the two most popular approaches towards QG: string theory and loop quantum gravity This has given added impetus to the established line of research dedicated to the investigation of ways in which fundamental symmetries, like LI or CPT, could be broken. It was realized that extremely precise tests could be made with a sensitivity appropriate to certain order of magnitude estimates of violations of LI.

AB - Introduction Although there is enormous uncertainty about the nature of Quantum Gravity (QG), one thing is quite certain: the commonly used ideas of space and time should break down at or before the Planck length is reached. For example, elementary scattering processes with a Planck-sized center-of-mass energy create large enough quantum fluctuations in the gravitational field that space-time can no longer be treated as a classical continuum. It is then natural to question the exactness of the Lorentz invariance (LI) that is pervasive in all more macroscopic theories. Exact LI requires that an object can be arbitrarily boosted. Since the corresponding Lorentz contractions involve arbitrarily small distances, there is an obvious tension with the expected breakdown of classical space-time at the Planck length. Indeed, quite general arguments are made that lead to violations of LI within the two most popular approaches towards QG: string theory and loop quantum gravity This has given added impetus to the established line of research dedicated to the investigation of ways in which fundamental symmetries, like LI or CPT, could be broken. It was realized that extremely precise tests could be made with a sensitivity appropriate to certain order of magnitude estimates of violations of LI.

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UR - http://www.scopus.com/inward/citedby.url?scp=84927081730&partnerID=8YFLogxK

U2 - 10.1017/CBO9780511575549.032

DO - 10.1017/CBO9780511575549.032

M3 - Chapter

SN - 9780521860451

VL - 9780521860451

SP - 528

EP - 547

BT - Approaches to Quantum Gravity

PB - Cambridge University Press

ER -