An artificial universe is defined that has entirely deterministic laws with exclusively local interactions, and that exhibits the fundamental quantum uncertainty phenomenon: superposed states mutually interfere, but only to the extent that no observation distinguishes among them. Showing how such a universe could be elucidates interpretational issues of actual quantum mechanics. The artificial universe is a much-simplified version of Everett's real-world model (the so-called multiple-worlds formulation). In the artificial world, as in Everett's model, the tradeoff between interference and observation is deducible from the universe formalism. Artificial world examples analogous to the quantum double-slit experiment and the EPR experiment are presented.
An artificial universe is defined that has entirely deterministic laws with exclusively local interactions, and that exhibits the fundamental quantum uncertainty phenomenon: superposed states mutually interfere, but only to the extent that no observation distinguishes among them. Showing how such a universe could be elucidates interpretational issues of actual quantum mechanics. The artificial universe is a much-simplified version of Everett's real-world model (the so-called multiple-worlds formulation). In the artificial world, as in Everett's model, the tradeoff between interference and observation is deducible from the universe formalism. Artificial world examples analogous to the quantum double-slit experiment and the EPR experiment are presented.
A non-relativistic quantum mechanical theory is proposed that describes the universe as a continuum of worlds whose mutual interference gives rise to quantum phenomena. A logical framework is introduced to properly deal with propositions about objects in a multiplicity of worlds. In this logical framework, the continuum of worlds is treated in analogy to the continuum of time points; both “time” and “world” are considered as mutually independent modes of existence. The theory combines elements of Bohmian mechanics and of Everett’s many-worlds interpretation; it has a clear ontology and a set of precisely defined postulates from where the predictions of standard quantum mechanics can be derived. Probability as given by the Born rule emerges as a consequence of insufficient knowledge of observers about which world it is that they live in. The theory describes a continuum of worlds rather than a single world or a discrete set of worlds, so it is similar in spirit to many-worlds interpretations based on Everett’s approach, without being actually reducible to these. In particular, there is no splitting of worlds, which is a typical feature of Everett-type theories. Altogether, the theory explains (1) the subjective occurrence of probabilities, (2) their quantitative value as given by the Born rule, and (3) the apparently random “collapse of the wavefunction” caused by the measurement, while still being an objectively deterministic theory.
As we saw in the previous chapter, the Everett interpretation seems to dispense with probabilities in quantum mechanics. Instead of describing a world for which many things are possible, but only some of those possibilities are actualised, it suggests a world in which all possibilities actually happen . Moreover, this is something of which we can be absolutely certain . Obviously, this does not straightforwardly fit our experience. We do not see multiple possibilities becoming actual. Whenever we measure a superposed particle, we observe only one property or another. Moreover, we have a very useful probabilistic rule to help us to predict what we will see. How can the success of this probabilistic rule be explained, if an Everett world does not involve any uncertainty? There are two main moves that are employed in response to this challenge. The first – what I call Stage A – is to show that there is a relevant sort of uncertainty, even in a universe where we are certain that everything will happen. The second move – Stage B – is to try to vindicate the probability of the Born rule in particular. That is, to show that we should not merely be uncertain about the future, but that we have good reason to attach the particular probabilities dictated by the Born rule to the possible outcomes of a quantum experiment. We will consider these two stages in turn.
We modify the Relative State Interpretation (RSI) of Quantum Mechanics so that it does not imply many worlds and parallel realities. We drop the assumption that probability amplitudes correspond one-to-one with reality: Not all information is contained in amplitudes, and not all amplitudes need be realized. Amplitudes do not "collapse" after a measurement, but evolve continuously, including unrealized ones. After each "event" only one possible outcome is realized. Therefore, if a value is measured, that value is real, all others are not; there is only one reality and one world. Reality content is "quantized" : unity for realized outcomes, zero for all others. It is "conserved": can move along any possible sequence of events, but only one at a time. The modified RSI is is strictly deterministic in the sense that the "global" probability amplitudes of the universe are determined for all times by the laws of physics and the initial conditions. They guide all events. But it is not deterministic in the sense that from the amplitudes one can not predict which outcome actually happens; that represents new information that accumulates as history unfolds. To the extent that information is part of the physical world, the coming into being of the universe is ongoing, even after the Big Bang. All predictions of the two versions agree, except possibly in esoteric, untested cases.
Quantum mechanics provides us most fundamental descriptions of our most early universe, but there is a long-standing debate amongst theoretical physicists about what all these mathematics really mean in real world? The present three-dimensional (3D) universe, we humans experience daily since our birth, is probably just one of an enormous numbers of essentially classical worlds, and all quantum phenomena arise from a universal force of repulsions that prevented many universes (Multiverse) from having identical physical configurations like ours. Probabilities arise only because of our human ignorance as to which in our world an observer occupies a position in space time. This picture is all that is needed to explain bizarre quantum effects such as particles that can tunnel through solid barriers and wave behavior in double-slit experiments or in a warm hole. Our many-interacting-universes approach hinges on our assumption that interactions between deterministically evolving worlds cause all quantum effects. Each world is simply the position of particles in three-dimensional space time, and each would evolve according to Newton’s laws, if there were no inter world interactions. A surprising feature of human approach was that the formulation contains nothing that corresponds to the mysterious quantum wave functions, except in the formal mathematical limit in which the number of worlds becomes infinitely large. Conversely, Newtonian mechanics corresponds to the opposite limit of just one world. Thus, our approach should incorporate both classical and quantum theory. As few as two interacting worlds can result in quantum like effects, such as tunneling through a barrier. Many interacting worlds theory (MIW) explains that rather than standing apart, an infinite number of universes in the early time shared the same space and time as ours. They show that the theory can explain quantum mechanical effects while leaving open the choice of theory to explain the universe at large scales. This is a fascinating new variant of multiverse theory that, in a sense, creates not just a doppelganger of everyone but an infinite number of them all overlaying each other in the same space and time. The fine tuning of parameters required to reproduce our present day universe suggests that our universe may simply be a region within an eternally inflating super-region. Many other regions beyond our observable universe might have existed in earlier times with each such universe governed by a different set of physical parameters and laws. Collision between these regions, if they occurred, should have left signatures of anisotropy in the cosmic microwave background (CMB) but have not been seen yet. We assess different mechanisms for this residual emission and conclude that although there is a 30% probability that noise fluctuations may cause foregrounds to fall within 3σ of the excess, there is less than a 0.5% probability that foregrounds can explain all the excess. A plausible explanation is that the collision of our universe with an alternate universe, whose baryon to photon ratio is a factor of ∼ 4500 larger than ours, could produce enhanced Hydrogen Paschen-series emission at the epoch of recombination. Future spectral mapping and deeper observations at 100 and 217 GHz are needed to mitigate systematics arising from unknown galactic foregrounds and to confirm this unusual hypothesis. After careful analysis of the spectrum of the CMB, Chary et al. found a signal that was about 4500x brighter than it should have been, based on the number of protons and electrons. Scientists believe that this existed in the very early universe. Indeed, this particular signal, an emission line that arose from the formation of atoms during the era of recombination is more consistent with a universe whose ratio of matter particles to photons is about 65x greater than our own. There is a 30% chance that this mysterious signal is just noise, and not really, a signal at all; however, it is also possible that it is real, and exists as a parallel universe. Keywords : Quantum mechanics, multiverse, Newtonian mechanics Cite this Article Pranab Kumar Bhattacharya, et al . Schrodinger Cat's Experiment's Interpretation and Parallel Universe or Multiple Universes. Research and Reviews: Journal of Space Science and Technology. 2016; 5(1): 35–52p.
This chapter introduces quantum mechanics through the experimental discoveries that revealed the limits of classical physics. Beginning with the historical debate over whether light is a wave or a particle, it examines Young’s double-slit experiment and its modern single-particle versions, which demonstrate that quantum objects can exist in superpositions of mutually exclusive states. The chapter explains how interference arises when alternative possibilities are not measured and how interaction with the environment suppresses these effects through decoherence, giving rise to classical behavior at macroscopic scales. A sequence of thought experiments involving interferometers and Stern–Gerlach devices highlights the counterintuitive structure of quantum measurement and the incompatibility of certain physical properties, as captured by the uncertainty principle. The chapter emphasizes that quantum mechanics does not describe particles taking multiple paths simultaneously in a classical sense but rather requires a new framework for probability based on amplitudes and interference. Finally, the discussion connects these foundational ideas to emerging technologies such as quantum computing, showing how superposition and entanglement can be harnessed to perform computations that have no classical analogue.
Among theories of the physical world, quantum mechanics remains a topic of lively discussions on its so-called interpretation. For some it remains an open question to understand how deterministic equations of this theory, as established long ago, may combine with a fundamental uncertainty. We consider the process of spontaneous emission by an atom interacting with infinite number of degrees of freedom of the electromagnetic field. There is uncertainty in the evolution of the photo-emission process which was characterized as Markovian by using the equations of quantum mechanics when the decay of the atom is due to the coupling with the vacuum field. The Markovian property leads us naturally to describe spontaneous emission by using the classical Kolmogorov equation for the probability evolution of a parameter defining the state of the atom. We explain that Everett’s many-worlds interpretation weld together our description, and appears therefore as a consequence of the equations of quantum mechanics, that solves in this case the riddle of deterministic equations describing random events.