Higher dimensions are dimensions higher then the normal 3 dimensions: Width,Length,and depth.
These dimensions are usually hidden from the 3 Dimensional world,however there are universes that exist in 4,5,and even higher dimensions.
Higher dimensions can be manipulated with using advanced technology(and other special unorthodox methods),and can even be used to preform grand feats. Such as time travel or even bending the laws of physics.
Known Dimensions(Space Time)
The 4th dimension only appears in the 3 Dimensional world in the form of time. However, it's true form can be utilized to be used as energy. Mostly used in time machines and time travel, this type of energy is highly dangerous. A volatile form of this energy is time residue, the literal remnants of a timeline branching into another through time travel, hence its name. It usually appears in the form of a blue glowing liquid. It is highly toxic to three dimensional beings and if used as a weapon can literally wipe things from existence.
One of the only known 4 dimensional forms used to do such a thing,is a substance known as "Tesseract". Tesseract is essentially a 4 dimensional cube. The only known uses of Tesseract was the Nightmare Irken's portal technology,and some of Invader Vex's technology and weaponry. It can also be used as ammunition,due to it's destructive capabilities. When Tesseract comes in contact with a third dimensional object at a high velocity,it will literally rip apart the fabric of that object.
Also,a variation of the Tesseract,in the form of energy was used in the flash runner. This energy allows it to change mass in the third dimension, creating warps through the fabric of space and into "Subspace" which is essentially a place where no laws of physics apply. The flash runner in specific then uses an advanced engine to boost far faster than it should be able to.
The 4th Dimension can also be used to alter or travel through time,although this has higher risks than most other methods. Using the 4th dimension for time manipulation can also be unstable.
The 5th Dimension is mostly unknown,but it is theorized to be capable of altering gravitational forces.
6th Dimensions and higher
6th dimensions and anything higher is largely responsible for "magic" and other "supernatural" oddities(Such as ghosts,demons,etc). This is because of these dimensions leaking into the 3 Dimensional world. This causes the creation of objects capable of distorting the laws of physics,and even defying known mathematical laws and logic itself. It is incredibly difficult to understand how these dimensions work,due to them being almost incomprehensible to 3 Dimensional beings. Also,they are almost impossible to fully study with modern science,even with the most highly advanced irken technology.
Due to these dimensions being completely unknown and practically incomprehensible,they are usually believed to simply not exist. Otherwise,most do not care enough about it to study it. Also,legends and conspiracy theories associating these dimensions with paranormal phenomenon,has reduced the study of these dimensions to not be taken seriously. Along with the rising religious worship of higher dimensions and cult groups. Most who study these dimensions are seen as pseudo-scientists or "horribly insane". Otherwise,they are seen as idiots.
Known universes with 6 dimensions or higher
- Vohhedrion Dimension ((assumed)15 dimensional)
- Time Dimension(Manipulation of 4th and 5th dimension)
- Fast Food Realms
- Fury Dimension
- Gensokyo(Manipulation of 6 dimensions and higher)
These dimensions are completely unknown to the Irken Empire and most other civilizations.
Contact with the 3D world
Due to the damage of an unknown multiversal disaster nearly (assumed)60 Centillion years ago,higher dimensions have leaked into the 3 Dimensional multiverse. This has caused higher dimensions to mix with the 3D world,distorting physics in certain areas of the multiverse. It has also led to the creation of unnatural objects in the multiverse,including entire universes that seem to break the laws of physics entirely or just dont make sense at all.
It has even lead to the creation of lifeforms with the incredible ability to defy physics,and even life after death.
Some of these creations even push the limits of physical laws to the point of ridiculousness,almost indistinguishable from "magic". It has even lead to the creation of god like beings.
These leaking dimensions are almost entirely responsible for the existence of paranormal phenomenon,super natural beings,"magic",and possible life after death.
However,strangely most of this "magical" phenomenon seemed to mostly be on Earth for unknown reasons. That is until rift activity skyrocketed 5 Irken years ago. Increased rift activity led to these unnatural dimensional objects to enter the Z-14 universe more easily and quickly.
It is said that higher dimensions is responsible for ghosts,demons,and other paranormal phenomenon,but most people see these theories as sheer nonsense. Higher dimensions also seems to the basis for legends of Dusq,as they describe him as an all powerful,evil being that exists in (unconfirmed)all 777 dimensions. It is said that only a choosen one can defeat him with a 6 dimensional golden sword made of pure "goodyiness".
There are also conspiracy theories of secret irken military bases,where experiments are being preformed on 4 dimensional creatures and 6 dimensional hypercubes. These theories are usually incredibly debunked however.
There are also many cults that been formed that worship 4 dimensional shapes and "666 dimensional powerful rainbow beings". Along with many secret socities formed.
There is also legend that somewhere,in the subterranean tunnels of planet dirt,lies a cavern home to a 4 dimensional cube-esque creature known as "The Tesserrisk". It is described as a black,cube shaped creature that constantly slightly changes it's form. In most witness accounts it is described to have yellow,glowing,crystal like arms. It also seems to have 4 glowing red dots for eyes,and makes loud distorted gibberish. It is usually known to be highly agressive,but has only (supposedly) killed one man.
Searches have been made to find the creature,but most have ended in failure. It is widely reguarded as a myth.
There are also legends of ancient irken leaders coming in contact with higher dimensional beings. These legends range from 0100 A.D. to 2345 B.C.(Irken Time). It is even theorized that higher dimensional beings helped the irkens through evolution in the distant past.