Endless Journey: Infinite Realms

Chapter 550 Intermission: A Discussion about the Multiverse From Earth“s Point of View

(This intermission is all about what people from Earth think about the Multiverse. All words that have been written here are real, so don’t doubt their credibilty.)

The multiverse, also known as a maniverse, megaverse, metaverse, omniverse, or meta-universe, is a hypothetical group of multiple universes.

Together, these universes comprise everything that exists: the entirety of space, time, matter, energy, information, and the physical laws and constants that describe them.

The different universes within the multiverse are called "parallel universes", "other universes", "alternate universes", or "alterverses".

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Multiple universes have been hypothesized in cosmology, physics, astronomy, religion, philosophy, transpersonal psychology, music and all kinds of literature, particularly in science fiction, comic books and fantasy.

In these contexts, parallel universes are also called "alternate universes", "quantum universes", "interpenetrating dimensions", "parallel universes", "parallel dimensions", "parallel worlds", "parallel realities", "quantum realities", "alternate realities", "alternate timelines", "alternate dimensions" and "dimensional planes".

The American philosopher and psychologist William James used the term "multiverse" in 1895, but in a different context. The term was first used in fiction and in its current physics context by Michael Moorcock in his 1963 SF Adventures novella The Sundered Worlds.

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The physics community has debated the various multiverse theories over time. Prominent physicists are divided about whether any other universes exist outside of our own.

Some physicists say the multiverse is not a legitimate topic of scientific inquiry.

Concerns have been raised about whether attempts to exempt the multiverse from experimental verification could erode public confidence in science and ultimately damage the study of fundamental physics.

Some have argued that the multiverse is a philosophical notion rather than a scientific hypothesis because it cannot be empirically falsified.

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In Dublin in 1952, Erwin Schrödinger gave a lecture in which he jocularly warned his audience that what he was about to say might "seem lunatic".

He said that when his equations seemed to describe several different histories, these were "not alternatives, but all really happen simultaneously".

In 2007, Nobel laureate Steven Weinberg suggested that if the multiverse existed, "the hope of finding a rational explanation for the precise values of quark masses and other constants of the standard model that we observe in our Big Bang is doomed, for their values would be an accident of the particular part of the multiverse in which we live."

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Scientists such as Stephen M. Feeney analyzed Wilkinson Microwave Anisotropy Probe data and claimed to find evidence suggesting that our universe collided with other universes in the distant past.

However, a more thorough analysis of data from the WMAP and from the Planck satellite, which has a resolution 3 times higher than WMAP, did not reveal any statistically significant evidence of such a bubble universe collision.

In addition, there was no evidence of any gravitational pull of other universes on ours.

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In his 2003 New York Times opinion piece, "A Brief History of the Multiverse", author and cosmologist Paul Davies offered a variety of arguments that multiverse theories are non-scientific:.

George Ellis, writing in August 2011, provided a criticism of the multiverse, and pointed out that it is not a traditional scientific theory.

He accepts that the multiverse is thought to exist far beyond the cosmological horizon. He emphasized that it is theorized to be so far away that it is unlikely any evidence will ever be found.

Ellis also explained that some theorists do not believe the lack of empirical testability falsifiability is a major concern, but he is opposed to that line of thinking:

Ellis says that scientists have proposed the idea of the multiverse as a way of explaining the nature of existence.

He points out that it ultimately leaves those questions unresolved because it is a metaphysical issue that cannot be resolved by empirical science. He argues that observational testing is at the core of science and should not be abandoned.

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Max Tegmark and Brian Greene have devised classification schemes for the various theoretical types of multiverses and universes that they might comprise.

Level IV: Ultimate ensemble: The ultimate mathematical universe hypothesis is Tegmark’s own hypothesis.

This level considers all universes to be equally real which can be described by different mathematical structures.

Level III: Many-worlds interpretation of quantum mechanics: Hugh Everett III’s many-worlds interpretation (MWI) is one of several mainstream interpretations of quantum mechanics.

In brief, one aspect of quantum mechanics is that certain observations cannot be predicted absolutely. Instead, there is a range of possible observations, each with a different probability.

According to the MWI, each of these possible observations corresponds to a different universe.

Suppose a six-sided die is thrown and that the result of the throw corresponds to a quantum mechanics observable. All six possible ways the die can fall correspond to six different universes.

Level II: Universes with different physical constants: In the eternal inflation theory, which is a variant of the cosmic inflation theory, the multiverse or space as a whole is stretching and will continue doing so forever, but some regions of space stop stretching and form distinct bubbles . Such bubbles are embryonic level I multiverses.

Different bubbles may experience different spontaneous symmetry breaking, which results in different properties, such as different physical constants. Related to the many-worlds idea are Richard Feynman’s multiple histories interpretation and H. Dieter Zeh’s many-minds interpretation.

Level I: An extension of our universe: A prediction of cosmic inflation is the existence of an infinite ergodic universe, which, being infinite, must contain Hubble volumes realizing all initial conditions.

Accordingly, an infinite universe will contain an infinite number of Hubble volumes, all having the same physical laws and physical constants. In regard to configurations such as the distribution of matter, almost all will differ from our Hubble volume.

However, because there are infinitely many, far beyond the cosmological horizon, there will eventually be Hubble volumes with similar, and even identical, configurations. Tegmark estimates that an identical volume to ours should be about 1010115 meters away from us.

This follows directly from the cosmological principle, wherein it is assumed that our Hubble volume is not special or unique.