Parallel Worlds

Paul Brenner

Yuqing Cui, Tianming Zhao, Rong-Xin Miao +2 more

Parallel worlds are imaginative ideas in quantum mechanics and cosmology. The superpositions of parallel worlds are novel states of quantum gravity and have no classical correspondences generally. In this letter, we investigate the superposition or the Schrödinger's cat state of optical parallel worlds, which could be realized in laboratory and may shed some light on the detection of parallel universes in a real world. We propose two realizable experimental schemes, which enable to explore the mysterious `parallel universes' by a Mach-Zehnder interferometer. The first one is based on an atomic ensemble in a superposition state, which is a fat Schrödinger's cat state. The second one is to prepare a photon in a superposition of different paths, where each path lies in an optical parallel universe.

Charles Goodwin

Mohammad H. Ansari, Yuli V. Nazarov

We present a compact and self-contained review of the recently developed Keldysh formalism for multiple parallel worlds. The formalism has been applied to consistent quantum evaluation of the flows of informational quantities, in particular, to the evaluation of Renyi and Shannon entropy flows. We start with the formulation of the standard and extended Keldysh techniques in a single world in a form convenient for our presentation. We explain the use of Keldysh contours encompassing multiple parallel worlds. In the end, we briefly summarize the concrete results obtained with the method.

Mariette DiChristina

Arbaaz Patel

This paper examines if the worlds depicted in anime series with their physics-defying events can exist in parallel worlds. Considering the Copenhagen Interpretation adopts the notion of wavefunction collapse, it is incompatible with the possibility of alternate universes existing. Thus, the Many Worlds Interpretation, which denies the possibility of this collapse and therefore allows other worlds to exist beyond ours, is adopted to argue that worlds parallel to ours with significantly different physical laws are highly unlikely to exist.