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Physics, Metaphysics and Cosmology Collide in New E-Book, Possibilities in Parallel: Seeking the Multiverse

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Possibilities in Parallel: Seeking the Multiverse

Possibilities in Parallel: Seeking the Multiverse

Parallel universes are a staple of science fiction, and it’s no wonder. They allow us to explore the question, “What if?” in a way that lets us step completely outside of the world we know, rather than question how that world might have turned out differently. For cosmologists, the question isn’t “What if the South won the Civil War?” but “What if the constants that make up the fundamental building blocks of physics were different?” Physicists argue that any slight change in the laws of physics would mean a disruption of the universe’s evolution, and thus our existence. Take gravity, for example: too strong and stars would burn through their fuel far more quickly. If the universe had expanded too fast, matter would spread out too thin for galaxies to form.

The list of examples goes on—to the point where the laws of physics might seem, dare we say, designed to make our existence possible. Short of a divine or supernatural explanation, one scientific possibility is that our universe isn’t the only one. That’s the idea explored in this e-Book, Possibilities in Parallel: Seeking the Multiverse. In section 1 we explore why scientists think other universes could exist. After that we get a look at the implications. Is it possible to have life in a universe with different physical laws? It would seem so. In “Cracking Open a Window,” Scientific American contributing editor George Musser discusses the possibility that our universe has more than three spatial dimensions—the others just happen to be very small. Other articles, including “The Universe’s Unseen Dimensions,” analyze the idea that our universe is one of many “branes”—three-dimensional structures stretched out over a higher-dimensional space. The concept of a parallel universe also touches time travel, and articles like David Deutsch’s and Michael Lockwood’s “The Quantum Physics of Time Travel” discuss the treatments of quantum theory that allow for it. It’s a triumph of the sciences that the very question of why the universe looks as it does can be asked at all. There are currently several possibilities for a multiverse, if it exists. Time and a lot of scientific spadework will reveal which one is right—and get us closer to answering those metaphysical questions: What if? Why us? Why now?





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  1. 1. M Tucker 4:55 pm 05/21/2013

    Until these physicists can find a way to prove multiple universes exist it will be nothing more than fantasy backed by some very fancy mathematics. I think the NAS ought to have another “Great Debate” like the one they had in 1920. That “controversy concerned the scale and makeup of the universe” and was only decided by actual evidence provided by Edwin Hubble.

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  2. 2. rloldershaw 11:10 pm 05/21/2013

    Speculations that are unable to generate definitive predictions (prior, feasible, quantitative, non-adjustable and unique to the theory being tested) do not meet the standards of science.

    They might be fun ideas to play around with, but they remain solidly in the pseudo-science category until they can at least make definitive predictions.

    When they can actually pass definitive predictions then that would be something for scientific journalists to bring to our attention.

    If you would like to see a powerful and more unified new paradigm (other than the just-so “multiverse”, i.e., the Great Delusional Hope for string theory)that can make definitive predictions and that can PASS definitive predictions, see:

    http://www.academia.edu/2917630/Predictions_of_Discrete_Scale_Relativity

    Then ask why scientific journalists show no interest in this new paradigm, which seems to deliver what they claim to want, and does it without invoking tooth-fairies or ad hoc fixes, unobservable new particles or unobservable extra dimensions.

    Strange days indeed in theoretical physics and scientific journalism!

    Robert L. Oldershaw
    http://www3.amherst.edu/~rloldershaw
    Discrete Scale Relativity/Fractal Cosmology

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  3. 3. david123 6:28 am 05/22/2013

    The multiverse is a hypothesis. It’s the leading hypothesis because nobody has another hypothesis which makes as much sense.

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  4. 4. christinaak 9:09 am 05/24/2013

    A much more reasonable hypothesis is an evolutionary cyclic model and that the current laws of physics have a long evolutionary history. An inherent thermodynamic instability exists in the universe (probably between gravity and an extremely powerful, repulsive force that has a subplanck length range). The universe expands to relieve this instability until it reaches a point in its development which also becomes unstable and causes it to contract. Upon cosmic collapse thermodynamic pressures cause subtle changes, and self organization processes result in the adaptations that produce new laws of physics (“parametric mutagenesis”-producing changes in cosmic parameters). Of course, there is probably very little change from one cosmic cycle to the next (not unlike what occurs with biological evolution). The advantage of this hypothesis over the “multiverse” conjecture is that it does not rely on the existence of outside agents (other universes) to explain the existence of the universe. The “Evolutionary Cyclic Model” hypothesis relies entirely on the existence of inherent properties to explain the complexity of our current universe.

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  5. 5. christinaak 11:57 am 05/24/2013

    Mutagenesis is a biological process concerning how mutations form or develop. In “General Systems Theory” (Ludwig von Bertalanffy) it is recognized that nature tends to make repetitive use of patterns (for example:homologous structure) in a variety of systems. It would not be surprising if a mutation like process is responsible for the eventual development of complexity in cosmic parameters (hence the concept: “Parametric Mutagenesis”). In biological evolution a mutagen that may be responsible for a mutation may be exposure to ultraviolet light (just one example). In cosmic evolution the ‘mutagen’ responsible for parametric mutagenesis may be tiny variations in thermodynamic pressures at the onset of a cosmic expansion phase. Christina A Knight

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  6. 6. jack.123 9:56 pm 05/28/2013

    Until Space-Time is defined all the rest is just speculation.There is almost certainly an unseen underling symmetry that will yield most of the answers that are now being sought.I think that when it is found it will be as beautiful as Einstein’s work.I believe that all the information that is needed is already been found and just needs a very bright person to put it all together.

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  7. 7. zankaon 2:56 pm 05/24/2014

    Philosophy of Time

    The nature of time has had extensive attention in part down through the ages, such as Plato, St. Augustine, Pascal, Leonardo, Newton etc. For example, Newton considered time to flow uniformly, as if it were a separate manifold (1-surface) from the 3-surface of his mechanics described universe.

    ‘Absolute, true, and mathematical time, of itself, and from its own nature, flows equably without relation to anything external…’   Newton’s Principia

    For a manifold, this would give a product space description M3 x M1 , the simplest fiber bundle description. Hence such description would be universal; that is the same common time for throughout the universe. Subsequently, the relativistic model refers to time as the interval between events for finite propagation, wherein clocks are associated with respective observers. However an event such as Big Bang, and concomitant Big Expansion of our 3-manifold (i.e. 3-surface), does not have such a General Relativity Theory description; nor is ‘initial’ 3-expansion (i.e. Hubble expansion) of our 3-volume limited by velocity of light, as in Special Relativity. Hence the possibility of further modeling in regards to how our 3-space and contents evolves.

    Might there be another common time description as to how our 3-volume evolves? Just as Gauss described curvature of a 2-surface intrinsic to such surface, and Riemann described curvature of a 3-surface as intrinsic to such surface, might not one analogously describe time as intrinsic to our changing 3-surface? Could the nonlinear Hubble expansion be utilized as such common time description for our 3-surface and perhaps for a set of such 3-surfaces i.e. 3-volumes, 3-manifolds; that is for misnomer, ‘multiple universes’? ‘Universe’ denotes all inclusiveness, rather than multi-universe which implies a set of such all inclusiveness. Hence better to refer to a set of 3-volumes i.e. 3-manifolds.

    Also non-linearity to Hubble expansion might even be of an always exponential nature, if it is just a specific example of the more general case: all explosiveness declines exponentially. So do all locations of our 3-volume, and for a possible set of 3-volumes, share the same common time i.e. common cosmic time? That is, perceiving the same Big Bang ~13.8 billion years ago; and thus the same ~2.7 degree kelvin temperature of cosmic background radiation for our now i.e. common positive definite modified global instant; a set of such instants mapping to the integers? Thus is there any necessity for inflation models?

    Also for a set of 3-volumes, contained in an array of planes, spherically symmetrical about a modified central force, might one also have a concomitant common cosmic time description intrinsic to System S≡{UT’, …} wherein UT constitutes an array of planes comprised of 3-volumes i.e. UT≡{{VvR}p} ? That is, might one utilize a positive definite thick spherical shell intersecting respective centers of all 3-volumes, denoting such common cosmic time for all patches of a given manifold, and for all 3-manifolds? This might be referred to as Modified Global Simultaneity (MGS) construct. Such set of successive concentric MGSs would also match (i.e. function) to the integers; having positive definite moments, corresponding to {ΔSTm ->0+} set of modified time separations. Also such set of MGSs could be rendered as always exponentially changing i.e. part of an exponential curve. Likewise for changing rate of Hubble expansion, intrinsic to each and all changing 3-volumes.

    Thus in such modeling, would one herein have two concomitant descriptions of an overall common cosmic time; the Hubble Expansion, intrinsic to a changing 3-volume, and MGS, intrinsic to an unending evolving dynamic System?

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