Multiverse Theory Explained: Relativity, String Theory, Inflation

Introduction
Hello everyone,
Today, we are very happy to present to you a fascinating and mysterious topic:
the multiverse theory.
Since a long time, humans have been asking questions about the origin of the
universe. For many years, people believed there is only one universe. But with
new scientific discoveries, this idea is being questioned. Some scientists now
think that there might be many universes, each with its own physical laws.
In our presentation, we will explain this theory in three main parts:
1. First, we will talk about the research that led to this idea.
2. Then, we will explain string theory, which supports the idea of multiple
universes.
3. Finally, we will talk about the theory of cosmic inflation, another
important concept to understand the multiverse.
1. How the multiverse idea started: relativity and the expanding
universe
Let’s start with Albert Einstein’s theory of relativity, published in 1915. This
theory changed the way we understand space, time, and gravity. It tells us that
space is not empty — it can stretch and bend. This idea helps scientists
describe the big structure of the universe.
In 1929, a scientist named Edwin Hubble discovered that galaxies are moving
away from us. This means the universe is expanding. Everything is getting
farther and farther apart. This idea supports the theory of the Big Bang, the
moment when the universe began.
At first, scientists thought this expansion would slow down over time. But in
1998, new observations showed something surprising: the expansion is not
slowing down — it’s going faster and faster. This is called accelerated
expansion.
To explain this, scientists introduced the idea of dark energy. Dark energy is a
mysterious force that pushes the universe to expand more and more. It makes
up about 70% of the universe, but we still don’t know exactly what it is.
2. String theory and the multiverse
One important theory that supports the idea of the multiverse is string theory.

String theory says that the smallest parts of the universe are not particles, but
tiny strings. These strings vibrate in different ways, and this creates all the
particles and forces in the universe.
But for string theory to work, the universe must have more than three
dimensions of space — it needs 10 or 11 dimensions. We can’t see the extra
dimensions because they are very small and hidden.
According to string theory, there are many possible ways the universe could
be built. Each way creates a different universe with different laws of physics.
That’s why string theory suggests the existence of a multiverse — a huge
number of possible universes.
3. Cosmic inflation and the multiverse
Another idea that supports the multiverse is cosmic inflation.
Cosmic inflation is a theory about how the universe expanded just after the Big
Bang. It says that the universe grew very, very fast in a tiny fraction of a second.
During this fast expansion, some regions of space stopped growing, while
others continued. This means that different “bubbles” of space were created
— each one could become its own universe. Together, all these “bubble
universes” form a multiverse.
Each bubble might have different rules, different particles, or even different
dimensions.
Conclusion
To sum up, the multiverse theory is not just science fiction. It is based on real
physics and ideas from string theory and cosmic inflation. Scientists are still
exploring this theory, and even if we can’t prove it yet, it helps us ask deep
questions about reality, space, and our place in the universe.