What is the multiverse theory?
In an attempt to explain our Universe, scientists have devised an idea called the multiverse. The multiverse theory proposes that our Universe is just one of many in an infinite number of multiverses, each having different laws of physics and constants of nature.
But how do we know whether this theory has any basis in reality? Is it possible to prove that the multiverse actually exists? This article explains what the multiverse is, how scientists discovered it, and where we go from here.
In physical cosmology and astronomy, the multiverse is a hypothetical group of multiple universes including the universe in which we live. Hypothetical universes beyond were formed by splitting from other universes.
The multiverse is not only composed of parallel universes that are similar to each other, but also includes empty space that exists between them. In physics and mathematics, alternative models for spacetime are investigated and require different spatial dimensions (for example, rotating spheres instead of a flat plane) or may include additional dimensions such as a compacted extra dimension called brane.
The term "multiverse" was coined in 1895 by American philosopher William James to indicate the confusing moral meaning of natural phenomena that have no other possible universes.
Are we living in a multiverse?
Are we living in a multiverse? Is there more than one universe? That’s what multiverse is all about. The multiverse is a hypothetical group of multiple universes that together comprise everything that exists: the entirety of space, time, matter, energy and phenomena.
In other words – it includes our universe, but also theoretically infinite other universes outside of our own existence. It is still very much a theory (albeit an intriguing one) and scientists have yet to discover any concrete evidence to support its possibility.
The multiverse is an idea born from the many versions of cosmology, quantum mechanics and philosophy which claim actual physical existence of various potential configurations and histories of the known observable universe. Many of the best scientific models for the creation of our universe depend on the existence of multiverses. This idea was not imposed upon society by imaginative science fiction writers; it arose from other premises, such as string theory and quantum mechanics. But if there are alternative universes that whirr undetected to the right of us - cosmologists call it the Multiverse - there are good reasons to consider it.
Based on research by cosmologist Alexander Vilenkin of Tufts University, who studied space and time, the entire space stopped inflating after the Big Bang and filled up into our own universe instead. We imagine the universe as a bubble, and it sits in a network of bubbles or universes in space.
How do parallel universes exist?
Scientists have theorized that an infinite number of alternative universes may exist alongside our own. The idea is not entirely without scientific precedent. One famous theory goes back to Einstein’s general theory of relativity, which includes a theory of everything, called string theory.
The broad strokes of string theory suggest that we live in a multiverse, where different universes are defined by what physics is like on their particular terms. Scientists believe that there may be as many as 10^500 universes.
This theory is called The Multiverse. Each universe has slightly different laws of physics, and some do not have intelligent life at all. In these different universes, anything that can happen does happen — somewhere.
Therefore, we should not be surprised if aliens exist elsewhere in our universe; it seems virtually impossible for life to arise on Earth given a few of our environmental conditions (e.g., our distance from other stars and high-energy radiation levels). Given how small our part of space is in relation to what else is out there — with so many potential Earths or habitable planets available — it would only make sense that alien life exists somewhere out there, too.
An Oxford University team has found evidence of a collision between our universe and another bubble universe in its early stages. The study’s main author, Professor Roger Penrose, says that it is not an alternative to an expanding universe but rather an extension of our ordinary notion of space-time.
In other words, it’s not a new theory as such but rather a prediction made by existing theories, which were corroborated using data from cosmic microwave background radiation. While that may sound like hot air (pun intended), there are strong reasons to believe Penrose might be right – notably because he was right about black holes before Stephen Hawking.
Is there any proof that we live in a multiverse?
A multiverse is a hypothetical group of multiple universes (and their potential variations) that together comprise everything that exists: in essence, it is the cosmological theory of everything. A typical multiverse consists of pocket universes called alternate worlds, or parallel universes.
These are based on theories such as quantum mechanics and string theory, which suggest that there are other worlds with different laws than our own universe. So far, there is no empirical evidence to support theories like quantum parallelism, although there have been proposals for experiments to test them—with inconclusive results so far.
Further limitations on the number of possible universes could arise by extending the analysis of the final boundary conditions of the multiverse. The main problem, according to Hossenfelder, is that multiverse theories are underdetermined and do not contain enough information to make such a calculation.
The theory of cosmic inflation supports the idea and states that thousands of universes from the same primordial vacuum have formed after the Big Bang and that the universe as we know it is observable to us. With singularity, it is possible that a new set of physical laws and different versions of those we know from different universes exist.
In cosmology, physics, astronomy, religion, philosophy, transpersonal psychology, music and all kinds of literature, especially science fiction, comics and fantasy there have been suspects of several universes. Max Tegmark's taxonomy of the universe summarizes the various theories of multiple universes. The hypothetical group of these universes is the multiverse, also called parallel universes, other universes, alternative universes, or many worlds.
Parallel universes (also called alternative universes, quantum universes, reached dimensions, parallel universes, parallel dimensions, parallel worlds, parallel realities, quantum realities, alternative realities or alternative realities) are alternative timelines, alternative dimensions or dimensional levels in some contexts.
In science fiction and science fiction, there is a concept that suggests that there are other universes beyond our own, and that the choices we make in life take place in alternative realities. This concept is called parallel universes and is a facet of the astronomical theory of the multiverse. Prominent physicists have split into other universes that exist alongside our own.
Multiverse theory shows that our universe, with hundreds of billions of galaxies and almost countless numbers of stars, spans tens of billions of light years, and may not be the only one. This theory states that the universe in which we live may not be the only universe in existence. The idea of the multiverse appears in many versions, mainly in cosmology, quantum mechanics, and philosophy, and often asserts the actual physical existence of several potential configurations or history of the known observable universe.
The multiverse is the idea that our universe and everything it contains is only a small part of a larger structure. This image of vast universes, much larger than the meager portion that we see constantly being created in this exponentially expanding space, is the essence of the Multiverse. If you have an inflationary universe governed by quantum physics, a multiverse is inevitable.
Advances in physics in the past 30 years have led some physicists and cosmologists to come to an amazing conclusion that the universe we live in is only one of many universes, perhaps infinitely many. If we look for evidence that exists outside of our visible universe and leaves no trace in it, it turns out that the idea of a multiverse is fundamentally unverifiable.
This may indicate that there is a more difficult-to-explore universe beyond the parts of the universe that we have access to, but it does not prove this, nor does it provide evidence for the existence of the multiverse. Joseph Polchinski of the University of California, Santa Barbara and Andrew Linde of Stanford University are theoretical physicists who invented the current inflation model and how it led to the island universe. They believe that the evidence is encoded in our space.
Since the concept of inflation has both a good theoretical background and support for observations, and since the process of creating new universes through inflation is based on fairly well-studied physics, this model of the multiverse has taken on much more importance than previous ideas.
This concept is called "parallel universe" and is an aspect of multiverse astronomy theory. This concept may sound a bit crazy, but when you start to think about its meaning, it becomes even stranger.
If the multiverse theory is correct, then there is a universe where everything is exactly the same as this universe, but you are reading this article, wearing a clown costume, and drinking a cup of maple syrup. From science fiction to science, there is a concept that suggests that there may be a universe different from ours, where all the choices you make in this life are unfolded in alternate realities.
Does The Multiverse Really Exist?
Science is a system based on observation and experimentation, and it is unclear if we will ever be able to observe another universe or determine if other universes actually exist. However, the theories of cosmology, quantum physics and the philosophy of science itself have some problems that could be solved if our mass were not everything, well, everything.
If mathematics is just a system we use to understand the universe, then there may be other mathematical structures in different universes. Many scientists believe that this theory of mathematical universality is accurate, and it indicates that there is likely to exist a universe independent of human experience. However, if mathematics is a basic reality, then every universe will also be determined by it.
However, if we are talking about quantum physics, the universe can refer to all fields and their particles and their cumulative influence on each other. What is interesting about this theory is that other universes may have completely different physical laws than ours, since they are not related to each other.
Or perhaps more universes could follow quantum mechanical theory (how subatomic particles behave) as part of a "baby universe" theory. In quantum theory, there may be other ways for more universes to arise. In his 1957 doctoral dissertation, American physicist Hugh Everett suggested that all possible options are real to each other, representing real realities - separate universes, if you will - just like everyone else knows.
What sets the universe apart in this multi-world interpretation is how each wave relates to a particular dimension of other waves, a phenomenon we call entanglement. In the so-called “many-worlds” quantum theory interpretation, which began in the 1950s and has recently sparked renewed interest, the universe essentially splits in two when a so-called quantum event occurs.
Likewise, all Level II bubble universes with different physical constants can in fact be discovered as "worlds" created by the "splitting" of spontaneous symmetry breaking in the Level III multiverse.
Moving from our universe to a Level I multiverse removes the need to specify initial conditions, an upgrade to Level II removes the need to specify physical constants, and a Level IV multiverse removes the need to specify ... One common feature across all four levels of the multiverse is that the simplest and perhaps most elegant theory includes parallel universes by default.
For example, an Everett-type multiverse may include different worlds, and each world is an eternally expanding multiverse, or eternal expansion may in principle produce several circular multiverses or from the creation of a sub-universe.
If there are a large number of (possibly infinite) universes, each of which may have different physical laws (or different fundamental physical constants), then some of them (though few) will have a combination of fundamental laws and parameters suitable for development.
Matter, astronomical structure, basic diversity, stars and planets, they can exist long enough for the emergence and development of life. In fact, there may be countless universes with their own laws of physics, their own collections of stars and galaxies (if stars and galaxies can exist in these universes), and they may even have their own intelligent civilizations.