Lorentz invariance and quantum gravity: an additional fine-tuning problem?

• Autores: Collins, John; Pérez, Alejandro; Sudarsky, Daniel; Urrutia, Luis F.; Vucetich, Héctor
• Año de publicación: 2004
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Física; Physics; Lorentz factor; Hořava–lifshitz gravity; Moving magnet and conductor problem; Velocity-addition formula; Theoretical physics; Quantum mechanics; Cpt symmetry; Vacuum expectation value; Lorentz covariance; Test theories of special relativity
• Institución: Universidad Nacional de La Plata

Trying to combine standard quantum field theories with gravity leads to a breakdown of the usual structure of space time at around the Planck length, 1.6 × 10⁻³⁵ m , with possible violations of Lorentz invariance. Calculations of preferred-frame effects in quantum gravity have further motivated high precision searches for Lorentz violation. Here, we explain that combining known elementary particle interactions with a Planck-scale preferred frame gives rise to Lorentz violation at the percent level, some 20 orders of magnitude higher than earlier estimates, unless the bare parameters of the theory are unnaturally strongly fine tuned. Therefore an important task is not just the improvement of the precision of searches for violations of Lorentz invariance, but also the search for theoretical mechanisms for automatically preserving Lorentz invariance.
Facultad de Ciencias Astronómicas y Geofísicas