Related papers: Nature abhors macroscopic superpositions
Using the relativistic concept of time dilation we show that a superposition of gravitational potentials can lead to nonunitary time evolution. For sufficiently weak gravitational potentials one can still define, for all intents and…
We study the dynamics of classical and quantum systems linearly interacting with a classical environment represented by an infinite set of harmonic oscillators. The environment induces a dynamical localization of the quantum state into a…
It is shown that for "ideal" macroscopic objects there are superselection rules forbidding superpositions of macroscopically distinguishable states of the objects. For real macroscopic bodies the notion of "weak" superselection rules is…
We propose a scheme to create a macroscopic ``Sch\"odinger cat'' state formed by two interacting Bose condensates. In analogy with quantum optics, where the control and engineering of quantum states can be maintained to a large extend, we…
In this paper, we propose a feasible scheme for generating the Schr\"{o}dinger cat states of a macroscopic mechanical resonator in pulsed cavity optomechanics. Starting with cooling the mechanical oscillator to its ground state, a red and a…
We demonstrate a break-down in the macroscopic (classical-like) dynamics of wave-packets in complex microscopic and mesoscopic collisions. This break-down manifests itself in coherent superpositions of the rotating clockwise and…
We consider quantum superposition states in Bose-Einstein condensates. A decoherence rate for the Schr\"odinger cat is calculated and shown to be a significant threat to this macroscopic quantum superposition of BEC's. An experimental…
Physical systems usually exhibit quantum behavior, such as superpositions and entanglement, only when they are sufficiently decoupled from a lossy environment. Paradoxically, a specially engineered interaction with the environment can…
We consider the creation of superpositions of macroscopically distinct states by a completely-positive (CP) operation on a subsystem. We conclude that the subsystem on which the CP operation acts must be macroscopically large if the success…
Many complex systems are representable as macroscopic set of elements which interact by simple rules. The complex macroscopically relevant phenomena are then the result of the generic emergence of a space-time multi-scale dynamics. Critical…
A cat state is a superposition of macroscopically distinct states. In quantum optics one such type of state is a superposition of distinct coherent states. Recently, a protocol has been proposed for preparing large optical cat states from a…
In the first paper of this series, I introduced a non-linear, Hamiltonian, generalization of Schroedinger's theory that blocks formation of macroscopic dispersion ("cats"). But that theory was entirely deterministic, and so the origin of…
The Schr\"odinger-Newton equation is a proposed model to explain the localization of macroscopic particles by suppressing quantum dispersion with the particle's own gravitational attraction. On cosmic scales, however, dark energy also acts…
We study the macroscopic superposition of light coherent states of the type Schrodinger cat states; analizying, in particular, the role of the temperature in the decoherence processes, characteristic of the superposition of macroscopic…
We show relations between superposition of macroscopically distinct states and entanglement. These relations lead to the important conclusion that if a state contains superposition of macroscopically distinct states, the state also contains…
We consider macroscopic, mesoscopic and "S-scopic" quantum superpositions of eigenstates of an observable, and develop some signatures for their existence. We define the extent, or size $S$ of a superposition, with respect to an observable…
The apparent conflict between general relativity and quantum mechanics remains one of the unresolved mysteries of the physical world. According to recent theories, this conflict results in gravity-induced quantum state reduction of…
A model is presented to describe the recently proposed experiment (J. Raimond, M. Brune and S. Haroche Phys. Rev. Lett {\bf 79}, 1964 (1997)) where a mesoscopic superposition of radiation states is prepared in a high-Q cavity which is…
Much of the discussion of decoherence has been in terms of a particle moving in one dimension that is placed in an initial superposition state (a Schr\"{o}dinger "cat" state) corresponding to two widely separated wave packets. Decoherence…
We summarize a recently proposed resolution of the quantum measurement problem. It stems from an insight into entanglement demonstrated in a 1991 experiment involving photon momenta. This experiment shows that, when two superposed quantum…