A Story of the Universe

Follow me through space and time.

Image of the Mountains of Creation from the NASA’s Spitzer Space Telescope
The Mountains of Creation. Image from the NASA’s Spitzer Space Telescope (NASA/JPL-Caltech/Harvard-Smithsonian).

The known is finite, the unknown is infinite; intellectually we stand on an islet in the midst of an illimitable ocean of inexplicability. Our business in every generation is to reclaim a little more land — Carl Sagan, Cosmos.

What’s the Big Bang Theory?

When you retrace the course of time, the universe is contracting. It becomes hotter and denser, up to a moment where everything was contained in a single point. A time zero is associated to this point. It’s called the Big Bang.

Illustration of the motion of distance galaxies which leads to the Big Bang theory.
The Big Bang theory originates from the observation that distant galaxies move away faster as their distance from us increases.

Where Do We Start?

However, after the Planck wall, the theories of space-time and elementary particles make powerful predictions, endorsed by experimental data decades after decades.

Illustration of the Big Bang theory around the Planck wall, including the coupling between the four forces of Nature.
Illustration of the Big Bang theory around the Planck wall, including the coupling between the four forces of Nature.
Physics beyond the Planck wall is speculation for the moment. After, gravity and the three other forces decoupled.

Inflation

When the Universe is 10⁻³² second, the distances in the baby universe have expanded by a factor at least 10²⁶! It’s like if you take an atom and you blow inside until it’s diameter is 100 times larger than the solar system.

Illustration of the Inflation in the early Universe, including the reheating stage where elementary particles are created.
Illustration of the Inflation in the early Universe, including the reheating stage where elementary particles are created.
During Inflation, most of the initial inhomogeneities are erased. The strong force decouples and elementary particles are created when Inflation stops.

Let There Be Matter

Let There Be Light

The light escapes in all directions in a magnificent snapshot of the infant universe. It screams « Freedom » in every nook and cranny of the Universe.

Illustration of the Big Bang theory until the Cosmic Microwave Background, including the four forces’ coupling.
Illustration of the Big Bang theory until the Cosmic Microwave Background, including the four forces’ coupling.
The initial content of the Universe was created in three minutes, but it took 380’000 more years for nuclei to form. After this moment, the light was free to move, and we can observe it today in what we call the CMB.

The Bright Era of Galaxies

Gravity is the creator and destroyer of worlds.

A new generation of stars rises from the ashes of their ancestors.

Illustration of the Big Bang theory from time 0 to the present day.
Illustration of the Big Bang theory from time 0 to the present day.
With our telescopes, we can go back in time up to the CMB. Our ingenuity and a bit of mathematics allowed us to retrace the course of time until the Planck wall and we are already pushing further.

To Go Further

I’m thrilled to share my knowledge, ideas and findings with you. Oh, and I also hold a Ph. D. in Physics.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store