Multiverse | Are there other universes?

Everything you can see, and everything you could possibly see, right now, assuming your eyes could detect all types of radiations around you -- is what we refer to as the Universe but what we really mean by that is the observable universe. That is the part of the whole universe that we’ve so far been able to see, in visible light, the farthest we can see comes from the cosmic microwave background, 13.8 billion years ago when the universe was opaque like thick fog. Cosmologists typically assume that our observable universe is just the nearby part of a greater entity known as "the universe" where the same physics applies. However there's solid physics supporting the idea that the universe we know and love could be one of many. 

in this article will talk about three distinct and largely unrelated proposed physical models for the multiverse, none of which has been tested or confirmed by experiment.

Model One : Holographic Multiverse

The holographic multiverse idea spirals from the holographic principle, which suggests that there exists a physically equivalent universe on the edge of our universe which is virtually identical in every sense. Think about it like the relationship of a three-dimensional object and its two-dimensional shadow. From the holographic principle it shows how the “shadow” has enough information of its universe that it is able to mirror its contents with precision.

Model Two : Brane Multiverse

String theorists proposed the idea that perhaps what we think of as our universe is actually just a three-dimensional surface embedded within a larger multiverse of many more three (or more) dimensional universes that stack right on top of each other in a higher dimensional space suggesting objects in our universe would not be able to interact with them because of our limitations to only three dimensions. 

Model Three : Quantum Multiverse

Many worlds, also known as parallel universes is one of the most out of this world interpretations of Quantum Mechanics and is commonly used in science fiction. The basic idea is that every possible alternate timeline for the universe is real, and they all happen in an ever-larger ever-branching way. Many people are fascinated by the term parallel universes, maybe it’s the appeal that alternative possible realities would exist and their lives turn out differently.

Bonus Model : Stimulated Multiverse 

The simulation hypothesis or simulation theory proposes that all of reality, including the earth and the universe, is in fact an artificial simulation, most likely a computer simulation.

Some versions rely on the development of a simulated reality, a proposed technology that would seem realistic enough to convince its inhabitants the simulation was real. The hypothesis has been a central plot device of many science fiction stories and films.

There is currently no experimental evidence to support any parallel universe hypothesis, but that’s not to say we couldn’t test these multiverse hypotheses. Fro example the many-worlds interpretation might be tested fairly soon, since experimentalists are becoming increasingly able to manipulate and control ever-larger quantum mechanical systems in their labs, systems that approach the line between quantum realm and our everyday experience.