Long story of the life of a droplet, from the Big Bang. Part 1: Water in the Universe.
Attention please, we would like to inform you that we had no choice but to make monstrous short cuts sometimes. We urge you to dig the subject.
The water molecule consists of an atom of oxygen for two atoms of hydrogen. Nevertheless, at the beginning, there was nothing, no molecules, no atoms, nothing. Before understand whence the water on Earth appeared, we need to understand where it came from in the Universe.
I – The Universe, a nutshell that grew a lot
This story began about 13.7 billion years ago. The expansion of our universe has just begun: it is the Big Bang. Everything was then nothing but energy and the universe was rather small at that time. The forces that govern our world (gravitational force, electromagnetic force, weak and strong interaction forces) do not yet exist. Our universe is, in fact, ruled by a superforce named ‘Supergravity’. Chemical elements we know today do not exist neither. This period without any differentiation of the forces and no chemicals is known as ‘primordial universe’.
In this primordial universe, the temperature is so high that this environment is only a “soup” of matter. The Universe then consists of only elementary particles: photons, neutrinos, quarks, leptons (including electrons) and their associated antiparticles. Think of those particles as bricks in a Lego box. If the Universe was a Lego box, those elementary particles would be the smallest that has been discovered.
1) Appearance of the elemental forces
About 10-43s after the Big Bang (a fraction of a fraction of seconds), the gravity force separates from the Supergravity. The result is an electronuclear force that includes weak and strong nuclear forces along with the electromagnetic force. At 10-35s, the strong nuclear force stands out from the electronuclear force and leaves aside the electroweak interaction. At 10-11s, the weak nuclear interaction finallly individualizes from the electromagnetic interaction. The four elementary interactions that governs our world are born: gravitational interaction, strong and weak nuclear interactions, electromagnetic interaction.
For a power negative integer (ex: 10-3; 10-4), you simply divide: 10-3 = 1 / (10 x 10 x 10) = 0,001.
Now you can imagine that 10-43 s is a really short amount of time.
2) Role of the different forces
You may wonder: why do we broach this topic of the different forces? Each in its way plays a specific and vital role. The electromagnetic force acts on electrically charged particles: differently charged particles (e.g. one positive, one negative; i.e. for instance one proton and one electron) attract each other; conversely (e.g. one positive with another positive particles, for instance two protons) they repel. The nucleus of atoms contains protons (they all carry a positive charge) and nucleons that carry no charges. Because of the positive charge of protons and the electromagnetic force, the protons should repel each other and the nucleus should blast. The strong nuclear force is responsible for the stability of nuclei and acts against the repulsion of protons. The weak nuclear interaction is responsible for phenomena like some radioactive decays or nuclear fusion (that both acts in the formation of chemical elements). Last but not least, gravity is responsible for the attraction between heavy objects (e.g. planets and meteorites).
For you to learn – The take home message
THM – Le côté obscure / The dark side of the force
For your own interest, you should look at the awesome videos of the SciShow. They explain what are the elementary forces very well (see below).
- Histoire du Big Bang: La Saga du Big Bang.
- Siegel, E. 2013. Science Blogs: What is the Big Bang all about?
- Siegel, E. 2016. Science Blogs: What Is The Strongest Force In The Universe? (Synopsis)
- Weinberg, S. 1993. The first 3 minutes. – Flamingo.
- Featured image By Lucianomendez (Own work) [<a href=”http://creativecommons.org/licenses/by-sa/3.0″>CC BY-SA 3.0</a> or <a href=”http://www.gnu.org/copyleft/fdl.html”>GFDL</a>], <a href=”https://commons.wikimedia.org/wiki/File%3AUpsilonAndromedae_D_moons.jpg”>via Wikimedia Commons</a>