Some parts of the universe are simply not observable.
Images of cosmic microwave background which encompasses the oldest light in the universe,
can only be observed until it reaches a barrier. That doesn’t prevent studies into
what might lie beyond. And that great beyond on the other side of the edge of the universe,
is really starting to look like a “multi-verse”. In this video, we’ll study the reports, and review
the evidence that mostly indicates the existence of the “multi-verse”.
“Our understanding of reality is not complete, by far. Reality exists independently of us.” It
sounds eerie. It sounds foreboding. And yet, it might actually be true.
These were the words of Stanford University physicist Andrei Linde, one of the architects
of cosmic inflationary theory which justifies the existence of the multiverse.
It’s understood that if those various parallel universes actually do exist, those universes
are separated from ours, unreachable, and so far undetectable by any direct measurement. And that
makes some experts question whether the search for a multiverse can ever truly be scientific.
But in the science fiction realm, humanity’s ideas about alternate realities are ancient
and futuristic. In 1848 Edgar Allan Poe composed a poem in which he fancied the existence of
“a limitless succession of Universes.” Moviegoers broke the box office with Spiderman: No Way Home,
Dr. Strange in the Multiverse of Madness, and the indie darling
Everything Everywhere All at Once. Aside from the mega movie studios providing excellent CGI to
create comic book favorites on the silver screen, our home video game units have also been bombarded
with themes revolving around the multiverse. Science fiction stories are full of creative
interactions between alternate realities. These days, the DC universe can collide with the Mortal
Kombat Universe, while the Marvel universe merges with the Capcom universe. It might
be our imagination in art, but art is a copy of reality! Depending on which cosmologist you ask,
the concept of a multiverse is more than pure fantasy or a handy storytelling device.
Fiction aside, the multiverse concept really took off when modern scientific theories attempting
to explain the properties of our universe predicted the existence of other universes
where events take place outside our reality. Let’s now break down the different theories
about a possible multiverse—including other universes with their own laws of physics—and
determine whether many versions of you could exist out there.
First things first, let’s be clear on our terminology. What is a multiverse?
The multiverse is a term that scientists use to designate the knowledge that beyond
the detectable universe, other universes certainly may exist additionally. Multiverses
are predicted by several scientific theories that describe different possible scenarios—from
regions of space in different dimensions or planes than our universe, to separate bubble universes
that are constantly popping into existence. The main point is that all of these theories
suggest the space and time we can observe is not the only reality. Humans once thought that Earth
was the center of the universe. Now we’re just discovering super massive black holes in the heart
of our galaxy. It would be conceited and even foolish to believe that our universe is the only
one that exists, given all of the discoveries made about space throughout the eras of time.
But don’t take it on faith. Science is not faith-based.
Science journalist Tom Siegfried, whose book The Number of the Heavens investigates how conceptions
of the multiverse have evolved over millennia, explains: “We cannot explain all the features of
our universe if there’s only one of them. Why are the fundamental constants of nature what they are?
Why is there enough time in our universe to make stars and planets?
Why do stars shine the way they do, with just the right amount of energy?
All of those things are questions we don’t have answers for in our physical theories.”
So, let’s get to these super suspenseful popular multiverse theories.
Inflationary Cosmology is perhaps the most scientifically accepted idea expounding that
in the minuscule moments after the big bang, the universe rapidly and exponentially expanded.
Cosmic inflation is a faster-than-light expansion of not only our universe,
but several others as well. Even more stunning is the fact that
the theory predicts that inflation could happen over and over again, perhaps infinitely. This
in turn could create a constellation of bubble universes. Not all of those bubbles will have the
same properties as our own—they might be spaces where physics behave differently. Some of them
might be similar to our universe, but they all exist beyond the realm we can directly observe.
Stanford University physicist Andrei Linde believes that: “This theory at first looked
like a piece of science fiction, although a very imaginative one. But it explained
so many interesting features of our world that people started taking it seriously.”
The next startling type of multiverse is called the many-worlds interpretation of
quantum mechanics, which is the theory that mathematically describes how matter behaves.
Proposed by physicist Hugh Everett in 1957, the many-worlds interpretation calculates the presence
of diverging timelines, or alternate realities in which our choices play out differently. And
of course, one slight change in decision-making can erect wildly different aftereffects.
Physicist James Kakalios of the University of Minnesota has written about the physics (or
not) of superheroes, and he was quoted saying, “Hugh Everett says, Look, there’s actually an
infinite number of parallel Earths, and when you do an experiment and you get the probabilities,
basically all that proves is that you live on the Earth where that was the
outcome of that experiment. But on other Earths, there’s a different outcome.”
According to this interpretation, versions of you could be off living the many different
possible lives you could have led if you’d made different decisions. However, the only reality
that’s perceptible to you is the one you inhabit. An action-packed blockbuster was released in 2001
depicting this scenario with the addition that humans were able to travel to several multiverses.
If one would eliminate his multiple-selves in the multiverse, their power would be shared among the
survivors until becoming the one and only. “The One” stars legendary martial artist Jet Li and his
then pupil Jason Statham. Aside from its intense action and fight choreography, it’s concept of the
multiverse makes it a must watch sci-fi flick about the multiverse. While watching, remember
that it’s possibly not all science fiction. So, if it’s not all superficial fiction for
entertainment, where do all of those other Earths exist?
Well, according to theoretical physicists, they’re all overlapping in dimensions we can’t access.
Over at the Massachusetts Institute of Technology, Max Tegmark refers to this type of multiverse
as a Level III multiverse, where multiple scenarios are playing out in branching realities.
Linde put it this way, “In the many-worlds interpretation, you still have an atomic bomb, you
just don’t know exactly when it’s going to go off. And maybe in some of those realities, it won’t.”
Multiple universes predicted by some theories of cosmic inflation are what Tegmark calls a Level
II multiverse, where fundamental physics can be different across the different universes.
In an inflationary multiverse, experts believe that “you do not even know if,
in some parts of the universe, atomic bombs are even possible in principle.”
But let’s get to the cold hard-core truth. Is there
any direct evidence suggesting multiverses exist? Well, even though certain features of the universe
seem to require the existence of a multiverse, nothing has been directly observed that suggests
it actually exist. So far, the evidence supporting the idea of a multiverse is purely theoretical,
and in some cases, philosophical. It remains one of those mysteries like dark matter and
anti-matter. Mathematically, it is accurate, yet tangible experiments are impossible, to date.
While some experts contend that it may be a grand cosmic coincidence that the big bang
forged a perfectly balanced universe that is just right for our existence, other scientists think
it is more probable that any number of physical universes exist, and that we simply inhabit the
one that has the right characteristics for our survival. Consider us Earthlings extremely lucky.
But it should be reiterated that an inestimable number of alternate little pocket universes,
or bubble universes, some of which have different physics or different fundamental constants,
is an idea that is so compelling because it helps address certain philosophical issues.
But since evidence of an alternate universe can’t be tested, so far, scientists argue about whether
the multiverse is even an empirically testable theory, at all. The definition of a multiverse is
independent from our own universe and impossible to access. But, hope remains as scientists have
not given up, and many of them figure that perhaps we just haven’t come up with the right test.
Siegfried believes, “The universe is not constrained by what some blobs of protoplasm
on a tiny little planet can figure out, or test.” Siegfried was quoted saying, “We can say, this is
not testable, therefore it can’t be real—but that just means we don’t know how to test it.
And maybe someday we’ll figure out how to test it, and maybe we won’t.
But the universe can do whatever it wants.” Are you a believer in the multiverse? What
bits of theory do you find more compelling to the existence of the multiverse or the lack of it?
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