Gravity

Gravity is one of the four Great Forces that split from the Superforce during Genesis. It is carried by gravitons.

Gravity acts as an attractive force between all objects with mass. It is generated by the interaction of matter with the Higgs Field. This generates it's carrier, the graviton, which in itself is effectively a minute distortion of spacetime.

Gravity is many orders of magnitude weaker than any of the other Great Forces, but it has an immensely powerful effect on the Universe due to it's powerful effects on large scale objects such as galaxies, stars and planets.

Function
Gravity is carried by gravitons, force carrier particles with no mass, no electrical charge and a particle spin of 2. Due to gravitons' zero mass, Gravity travels at light speed and has an infinite range (although it gets weaker further from it's source).

Gravitons are produced by all objects with mass. Any particle with mass continually interacts with the Higgs bosons of the Higgs Field, and each interaction releases a graviton. Objects with no mass do not interact with the Higgs Field field, and so do not release gravitons, and have no Gravity.

Scale
Gravity is by far the weakest of the four Great Forces in terms of the relative power of it's carrier, the graviton being over 100 octillion (1029) times weaker than the W and Z bosons.

Due to this, individual gravitons have effects so minute that the force has virtually no effect on the subatomic level, even though every subatomic particle with mass (including other force carriers like the W and Z bosons) generates gravitons when it comes into contact with a Higgs boson.

Even on macroscopic objects, Gravity's attractive force has virtually no effect. Gravity only begins to have an effect with objects of cosmological size. Objects larger than about 1 trillion metric tonnes (the weight of a small asteroid) are generally considered the threshold where Gravity starts to be noticeable, generating enough to draw other objects towards them.

Objects with masses in excess of a 1 quintillion (1018) metric tonnes have sufficient gravity to crush them into a round shape. These objects are dwarf planets and planets. Larger planets have sufficient gravity to draw in great quantities of gas and create atmospheres. Gas giants form when objects have 15 to 20 Earth masses, and objects with 30,000 Earth masses can initiate nuclear fusion in their interiors and become stars. Stars with 20 solar masses (6 million Earth masses) have such enormous gravity that they are capable of creating black holes at the end of their lifetimes.

Black holes
"Main article: Black hole"

Black holes are objects with such an immense gravitational field that nothing, not even light, can escape. Due to this, black holes have the appearance of black orbs, the black region being the point beyond which light cannot escape. The space next to a black hole appears distorted, this is due to the immense gravity bending rays of light.

Despite their appearance as sizable orbs of darkness, black holes are in fact elementary particles with enormous mass, the black orb surrounding them simply being their immensely strong gravity preventing light from escaping.

Black holes are some of the most stable objects in the Universe. They are almost impossible to destroy, their immense gravity allowing them to absorb all energy they encounter. Black holes decay via hawking radiation, the smallest taking over 1068years to decay. Black holes gravitational effects are the most extreme in the Universe. Black holes could collide, generating gravitational waves, concentrated streams of gravitons, some of the most powerful phenomena in the Universe.

Dark matter
Dark matter is a unique substance that, despite it's name, has little in common with matter. It is a substance with no physical presence and no mass (at least in the conventional sense), as it does not interact normally with the momenton field as matter does. However, dark matter does generate gravity, and is also weakly affected by it.

Dark matter is drawn towards massive concentrations of mass and gravity, especially supermassive black holes, objects that often form the centers of galaxies. Dark matter is not consumed by black holes, however, but remains surrounding them.

The excess gravity generated by dark matter surrounding supermassive black holes is an important factor in the holding together of galaxies, allowing them to grow to enormous sizes that a a supermassive black hole alone could not keep in orbit.

Antigravity
Antigravity, or negative gravity is possible if antigravitons (gravitons with a negative "gravitational charge") are produced. Such particles produce a distortion of spacetime in the same way that regular gravitons do, but in the opposite direction. Antigravitons can only be produced if negative matter interacted with the momenton field.

In practice, antigravity is not used in technology, since negative matter is immensely difficult to procure and antigravitational effects can be created using tractism.