# Fundamental decoherence from quantum gravity: a pedagogical review

@article{Gambini2007FundamentalDF, title={Fundamental decoherence from quantum gravity: a pedagogical review}, author={Rodolfo Gambini and Rafael A. Porto and Jorge Pullin}, journal={General Relativity and Gravitation}, year={2007}, volume={39}, pages={1143-1156} }

We present a discussion of the fundamental loss of unitarity that appears in quantum mechanics due to the use of a physical apparatus to measure time. This induces a decoherence effect that is independent of any interaction with the environment and appears in addition to any usual environmental decoherence. The discussion is framed self consistently and aimed to general physicists. We derive the modified Schrödinger equation that arises in quantum mechanics with real clocks and discuss the… Expand

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#### References

SHOWING 1-10 OF 48 REFERENCES

Decoherence, the measurement problem, and interpretations of quantum mechanics

- Physics
- 2005

Environment-induced decoherence and superselection have been a subject of intensive research over the past two decades, yet their implications for the foundational problems of quantum mechanics, most… Expand

Fundamental decoherence in quantum gravity

- Physics
- 2005

A recently introduced discrete formalism allows to solve the problem of time in quantum gravity in a relational manner. Quantum mechanics formulated with a relational time is not exactly unitary and… Expand

Intrinsic decoherence in quantum mechanics.

- Physics, Medicine
- Physical review. A, Atomic, molecular, and optical physics
- 1991

A model for intrinsic decoherence in quantum mechanics is proposed, based on a simple modification of unitary Schrodinger evolution, with testable consequences including anomalous dispersion of a free particle, decay of oscillatory systems, destruction of interference-fringe visibility, and a phase shift of interference fringes. Expand

Possibility of observing energy decoherence due to quantum gravity (7 pages)

- Physics
- 2004

It has recently been proposed that quantum gravity might lead to the decoherence of superpositions in energy, corresponding to a discretization of time at the Planck scale. The proposal seems… Expand

Relativistic Invariance and Quantum Phenomena

- Physics
- 1957

The principal theme of this discourse is the great difference between the relation of special relativity and quantum theory on the one hand, and general relativity and quantum theory on the other.… Expand

Realistic clocks, universal decoherence, and the black hole information paradox.

- Physics, Medicine
- Physical review letters
- 2004

This work estimates the rate of the universal loss of unitarity using optimal realistic clocks and observes that the rate is rapid enough to eliminate the black hole information puzzle: all information is lost through the fundamental decoherence before the black Hole can evaporate. Expand

A relational solution to the problem of time in quantum mechanics and quantum gravity: a fundamental mechanism for quantum decoherence

- Physics
- 2004

The use of a relational time in quantum mechanics is a framework in which one promotes to quantum operators all variables in a system, and later chooses one of the variables to operate like a… Expand

Search for violations of quantum mechanics

- Physics
- 1984

The treatment of quantum effects in gravitational fields indicates that pure states may evolve into mixed states, and Hawking has proposed modifications of the axioms of field theory which… Expand

LIMIT TO SPACE-TIME MEASUREMENT

- Physics
- 1994

Applying simultaneously the principles of quantum mechanics and general relativity we find an intrinsic limitation to quantum measurements of space-time distances. The intrinsic uncertainty of a… Expand

Comment on 'Uncertainty in measurements of distance'

- Physics
- 2002

We have argued that quantum mechanics and general relativity give a lower bound δl l1/3l2/3P on the measurement uncertainty of any distance l much greater than the Planck length lP. Recently Baez and… Expand