Do we live in a multiverse?

 the multiverse science fiction  or science fact though the jury's still  out on this one there are some very  compelling arguments supporting the case  both for  and against the fact that our universe  is not unique  and that there very well may be others  in existence welcome to   today we're finding out how truly small  we are as we discover  the multiverse we've all seen this idea  played out in shows like star trek and  doctor who  plots revolving around the notion that  alternate realities exist  places where choices you didn't make in  this life are played out  similar to a road that forks into a  right and left-handed side path  there is actually a bit of evidence out  there leaning towards the possibility  that there is indeed a multiverse  as well as a host of theories aiming to  explain the why  and the how the argument 4  it's widely accepted that 13.7 billion  years ago there was a singularity of  near  infinite potential that was caused to  violently expand and inflate  forming three-dimensional space this is  known as the big bang  and we still don't know what the  stimulus was for this sudden phenomenon  after an initial period of inflation the  energy began to cool  as this rapid expansion slowed down  creating light photons  eventually small particles began to form  and clumped together to form the matter  that planets  stars and whole galaxies are made of  today  the universe is estimated to be 93  billion light years in diameter  growing larger every minute the big  issue is that we're limited to what we  can observe in this  universe there's no way to take a peek  outside of our bubble of existence and  check what's out there  many of the best scientific models  explaining the creation of our universe  actually depend on the existence of a  multiverse to work  they come in many different flavors  depending on who you ask  another universe could be exactly the  same as our own  following the same rules or it could be  based on an entirely new set of physical  laws  then again it could follow the same laws  of physics but have started in a  different way  or by another stimulus or perhaps the  same fundamental laws of physics with  bylaws supporting other types of matter  and energy not present in our universe  the proof we're looking for could be in  the hot and cold spots found in the  cosmic microwave background or cmb  the afterglow of the big bang these  discrepancies could be proof  of colliding universes gravitational  waves might provide  evidence that the cosmic inflation  period after the big bang  put curls and ripples into the cmb  confused yet infinite universes  the prominent model of space-time  accepted by science is similar to that  of a bed sheet  it continues on forever punctuated by  the gravitational forces of black holes  similar to a bowling ball making a  depression in said bed sheet  if space-time is infinite that at some  point it must start repeating itself  there is only so much matter in the  universe and a finite number of ways it  can be arranged  if it were possible to travel far enough  would you eventually stumble across  another version of you  or infinite versions these doppelgangers  could be only slightly different to  yourself  for example wearing a blue shirt to your  red or vastly different  leading to completely different life and  career paths  the observable universe extends only as  far as light has had the chance to  travel since the big bang  13.7 billion light years  the area beyond our sphere of vision  could in theory be an  entirely separate universe from what we  can observe  space isn't positively or negatively  curved  and if it is in fact curved then its  diameter is hundreds of  thousands of times wider than what we  can see in short there is a whole lot  more out there  than we think bubble universes  multiple universes could also arise from  eternal inflation  following the big bang the universe was  blown up much like a party balloon  some pockets of space may stop inflating  while others continue to expand  creating isolated bubble universes  our universe's inflation has stopped  allowing for the formation of galaxies  and celestial bodies  we may exist as a small bubble in a sea  of  infinite and ever inflating space time  other pockets may have stopped their  rapid inflation forming  other isolated bubble universes the laws  of physics in these other  planes may be entirely different to ours  in terms of how energy relates to matter  how gravitational forces work and even  how subatomic particles interact with  the quantum realm  parallel universes this is what most  people think of when they hear the word  multiverse  this idea is actually a facet of string  theory that each universe is a membrane  that hovers just out of reach of the  other membrane universes or brain worlds  extends in three dimensions with time  being the fourth  these other brain worlds may be floating  in higher dimensional space  outside of our capabilities to detect  them think  individual layers sitting on top of each  other in a bag of sliced bread  a cosmic loaf if you will there's more  the layers may not be perfectly parallel  and at times may smash into each other  causing big bangs that  reset the universe over and over again  in a cycle with no beginning and no end  daughter universes universes could  follow the theory of quantum mechanics  and how subatomic particles behave  for example a universe may be born  dependent on every possible outcome from  a decision you make  one for every choice kind of like that  movie sliding doors  quantum mechanics are a set of  parameters based on probability  not definite outcomes as a result  mathematics within this theory point to  the fact that all  outcomes relative to a situation occur  resulting in separate or daughter  universes born out of the initial or  parent universe  mathematical universes this one will  really bake your noodle  mathematics forms the basis of our  understanding of physics and the  space-time continuum  but there is a big but is math just a  way to describe the universe a tool for  quantifying matter and the forces acting  upon it  or could it be reality unto itself  a place where our observations are  nothing more than imperfect perceptions  of the mathematical universe's true  nature if this were the case  then would other universes exist under  other mathematical structures that  cannot logically  exist in our universe in a way infinite  universes based on an  infinite set of different mathematical  equations  that influence how the universe behaves  around them  the argument against theories hinting at  the existence of the multiverse are just  that  theories they cannot be proven and are  models made up  in an attempt to explain the unknown  why do fundamental constants have the  values they do  why are the laws of physics this certain  way string theory is a framework that  seeks to explain how constants and laws  relate to each other  but also how other laws and other  constants have related to each other as  well  essentially if we are part of a gigantic  infinite multiverse  then there are no limits to the  combination of physics that could exist  in  different regions of space time that may  sound awesome but there is one inherent  flaw in the logic  it's all speculation there's no way to  test out string theory and no particular  reason why it's safe to presume that  inflating  space-time beyond our field of vision  would have different laws of physics to  our own universe  it may all just be the same in one  never-ending universe  the multiverse isn't a specific  scientific theory all on its own it's  more of a concept a theoretical  possibility borne out of some theories  that seek to explain why the laws of  physics are the way they are  and how the universe started that's  given that space-time actually has a  beginning  and an end and isn't an infinite  continuous thing  each theory that hints at the existence  of a multiverse has a different idea of  what that multiverse would be like  and how things are in each other  alternate universe  ask a different supporter of each theory  and you'll get a different answer as to  what the multiverse actually is  when conclusions are drawn about  fundamental constants in the laws of  physics without evidence or a way to  test a hypothesis  it's no longer science it's just  speculation and fantasy  the verdict this leaves the multiverse  in a tricky spot  there's likely no way science will ever  be able to gather enough  evidence to either rule out or confirm  its existence  more to the point theoretical physics is  just that  theoretical and unable to be proven  in saying that it was only 500 odd years  ago that copernicus proposed the  heliocentric theory  prior to that it was thought that the  earth was the center of the solar system  over time things change new ideas arise  and astronomical theory changes and  adjust to accommodate accepted theory  in 100 years any one of these five  multiverse theories may become the norm  the way we explain the metaphysical  world around us