Forces

There are four fundamental forces of nature:

* Strong nuclear force
* Electromagnetic force
* Weak nuclear force
* Gravity, which does not play a role in the Elementary Craft mod.

In the ElementaryCraft mod the player will encounter the following game mechanics related to the fundamental forces.

The electromagnetic force: particles that have a charge, such as electrons and positrons, will repel or attract one another.

The weak force: particles can undergo the nuclear decay process, which will transform certain particles into others.

The strong force: the strong force acts as the glue for the hadrons such as the proton and neutron, and the players will always need to add gluons (force carriers of the strong force) when crafting these particles.

# Dive deeper into the Physics: forces

There are four fundamental forces in the universe: the electromagnetic force, the strong force, the weak force and the gravitational force. The latter one, the gravitational force, is different from the others. We will not encounter the gravitational force in the following.

We saw earlier in the section about quantum fields, that there are two kinds of particles, namely matter particles and messenger particles. You can consider matter particles as the actual building blocks of matter. Whereas, the messenger particles ensure that the forces are transferred between the particles.

A particle experiences a certain force when that particle is able to exchange the corresponding messenger particles. For example, an electron experiences the electromagnetic force because the electron is able to exchange (capture and emit) photons.

There are different forces:

* the electromagnetic force transmitted by photons
* the strong nuclear force that has the gluons as messenger particles
* the weak nuclear force transmitted by the weak gauge bosons (Z, W+, W-). In Elementary Craft, only the W boson is considered, and no distinction is made between W+ and W-.
* (gravity is disregarded because it is described by the curvature of spacetime)

That a particle is able to exchange certain messenger particles is indicated by its charge.

* The electrical charge of a particle indicates whether the particle can exchange photons (and is therefore subject to the electromagnetic force)
* The color charge indicates whether a particle can exchange gluons (and is therefore subject to the strong nuclear force)
* The weak isospin (just call it the weak charge) indicates whether a particle can exchange weak gauge bosons (and is therefore subject to the weak nuclear force)

The charge of some matter particles is shown in the figure. A charged particle thus spontaneously creates messenger particles. For example, an electron will spontaneously extract photons from the photon quantum field and emit them.

Some messenger particles also carry a charge themselves. The weak gauge bosons W+ and W- have an electrical charge (when they occur in an interaction, they must obey conservation of charge), the gluons themselves are also colored. That is, the gluons emitted by quarks can also emit gluons themselves, which is why the strong nuclear force is so strong, because the "glue" itself makes "more glue."

In case of interactions, the charges must always be retained.