Cosmosphere

A Cosmosphere (コスモスフィア)is the Soulspace of a Reyvateil, which is always stored inside a SH Server. Strictly speaking, it is the agglomeration of Static H-Waves that give form to the very soul of the Reyvateil, which is at its core composed of sounds, and it generally is recorded in the SH_RAM part of the SH Server, which is a device made of Parameno. Given the H-Wave absorption properties of said material, that makes it perfect to record, store and preserve the minds of the Reyvateils.

It must be mentioned that the Cosmospheres also receive the name of "Logic of the Reyvateils", and it bases its formation on the Spiritual Standard Frequency that is unique to each individual Reyvateil. If a Reyvateil has a similar Spiritual Standard Frequency to other, they both will become able to empathize more easily and will turn into great friends.

A Cosmosphere generally contains manifestations of a Reyvateil's feelings, memories, fears, traumas, and in the deeper levels, it is also possible to see her true personality, which generally not even the Reyvateil herself knows about. By Diving into a Cosmosphere and triggering events on it, it is possible for Reyvateils to craft Song Magic far more easily than if they tried crafting them in the real world. However, it must be noted that the Reyvateil herself never remembers what happens after a Dive unless she is capable of manipulating her Cosmosphere, as she is in a state akin to that of dreaming when a Dive takes place.

The Cosmospheres are protected by beings created out of fond memories or items to the Reyvateil called Mind Guardians, which have the duty of making sure that no Diver tries to bring harm to the mind of their master, as well as making sure that only those which the Reyvateil trusts enough come into her mind and also giving assistance to the Diver during their trip through the Cosmosphere. The exception to this are the IPDs, as due to Infel Phira's specifications, they lack Mind Guardians.

All Cosmospheres have as standard two locations called the Stonehenge and the Tower of Life, both of which are the interfaces that connect the Reyvateil to the Tower: the Stonehenge is an I/O Port, while the Tower of Life serves as the point of connection between them and the SH Server. The Stonehenge is always the point in which the Diver will appear upon entering the Cosmosphere, while the Tower of Life is invisible at first and only appears as a field of energy, but is the final destination of the Cosmosphere due to completion of the ninth and final level taking place at it. However, the Tower of Life isn't visible in Sol Cluster Reyvateils due to the Dive Machines in that region being configured to render them invisible to the Divers.

Etimology
The word Cosmosphere comes from the union of the words "Cosmo" (microcosm) and "Sphere" (space), so it is a pormentau meaning "Space of the Microcosm", referring to how it is the place where the microcosm formed by the mind of a Reyvateil is deployed.

Formation
All Pureblood Reyvateils have a Cosmosphere from they time are born, but it isn't yet structured in a shape that anyone could define as a world: it is instead a massive chaotic sea of energy and feelings, which would endanger the lives of both the Reyvateils and Divers if such a Dive was attempted. For this reason, Diving isn't allowed until the Reyvateil is of 13 years of age or older, as it is that point that the Cosmosphere finally takes the form of a proper structured world.

On the other hand, Halfblood Reyvateils don't have Cosmospheres until the point they awaken: at that point, the SH Server's LEM accesses the H-Wave band located in their brains and begins copying their memories, feelings and personality into the SH Server, making the Cosmosphere a mirror of everything the Reyvateil has in her brain. This process takes up to ten days to complete, during which the Reyvateil will be in coma with a high fever. Additionally, the SH Server and the brain of the Reyvtail undergo constant synchronization to ensure that the contents of one are exact copies of the other, therefore preventing any sudden memory losses or inconsistencies in personality. However, this also applies for negative events: any damage the Reyvateil's mind receives will also be copied by both parts, having the final consequence that if the SH Server is destroyed or reformatted, the Reyvateil will receive severe damage to her mind and could even end up dying from the shock.

Location
As mentioned previously, the Cosmospheres of the Pureblood Reyvateils exist solely in the SH Server while the ones of the Halfbloods exist in their brains and have a mirror of them in the SH Server. However, strictly speaking, the Cosmospheres are actually compartments of the Cosmosphere of a bodiless Reyvateil called β-6D. β-6D's Cosmosphere is partitioned in order to allow the SH Server to host the Cosmosphere of all the other Reyvateils, therefore making them into alternate personalities or imaginary friends of β-6D that were given a physical body.

This means that all the Reyvateils are connected at a subconcious level, as their common unconscious; known by the formal name of Shared Consciousness Fields, which is located beyond the Boundary Gate and deeper than the highest Cosmosphere stratum (Level 9), is the conscious mind of β-6D. However, this poses a danger if the Reyvateils at large are stressed out and anxious: if this happens, these feelings will spread throughout β-6D and cause all other Reyvateils to feel anxiety and animosity even if their current situation is a relaxed setting,

Structure
The Cosmosphere is formally formed by nine layers that go from around the 20000 Hz band to around the 1100000 Hz band. There are higher frequency bands that deal with the H-Waves beyond them, but as they belong to the Hymn Code and Shared Consciousness Fields parts of their minds, they don't correspond to their individual Cosmospheres.

As for the nine layers, they generally can be classified under the following categories:

Imaginary World
Also called a world of delusions. Explained in a simple way, it could be said that this world is tabletop RPG game world in which the Cosmosphere's owner acts as the Game Master. Generally, only Pureblood β-Type Reyvateils and Third Generations that have trained themselves hard enough to manipulate the contents of their Cosmospheres can create imaginary worlds, as this is a feat that requires abilities akin to that of lucid dreaming. This section of the Cosmosphere generally never represents any of the true aspects of the Reyvateil herself due to being a false world, and since her conscious self is still in relative control of this area, she can also conceal anything she doesn't want the Diver to see.

Memory World
The place where memories of the past can be seen, particularly sad and traumatic ones. This is the usual Cosmosphere seen in Halfblood Reyvateils given their lack to manipulate their own minds, so the Diver will generaly be cast into a storm of memories and feelings the instant they step into the Cosmosphere. This area also receives the name of Memory Field and is usually located at either the third or fourth strata, and as the name says, it usually bears vivid recollections of particularly painful or traumatic memories, which the Reyvateil herself might hide consciously, but they still continue causing strain on her mind due to being unable to cope or heal them by herself. Usually, the best method for the Reyvateil to grow spiritually is that the Diver faces alongside her the cause of these scars and helps her to come to terms with it.

True Self World
While these are worlds that the conscious self of the Reyvateil can't see or reach, due to being located in the deeper strata (from Lv. 5 onwards), these actually depict what the Reyvateil truly wants to do and how she wants to be. It could be also said that this place is the one that manifests the ego of the Reyvateil the most, unfettered by morality, duties and such other matters of the real world. Due to this, the Reyvateil usually appears here as an amoral dictator bent on realizing her deepest wishes without anyone else having any say on the matter.

Normally, the Reyvateil's conscious self is unaware of any of these wishes, but there are occasions in which the wishes of her conscious self are in direct contradiction with those of the selves found in the True Self Worlds, or the actions she commits in this type of Cosmosphere could end up causing irreparable damage to her conscious self and mind if they came to pass. Such happenings are known as Paradox Loops, and are usually extremely dangerous, as if they aren't resolved or handled correctly, it could lead to the destruction of the current Cosmosphere stratum and could even cause the complete collapse of her mind. This is why Diving in such levels is so risky.

Boundary Gate
An enormous gate located in the Tower of Life area of the Cosmosphere, which is present in the Cosmospheres of all Reyvateils. The Tower of Life is the representation of their connection with the SH Server, making it an umbilical cord of sorts between them and the Tower, and it is also the point that connects their Cosmospheres with the Binary Field, allowing the flow of feelings and energy between them, which is what makes Song Magic possible.

Given the enormous amounts of energy that flow into the Reyvateils from the SH Server into their Cosmospheres, there needs to be a barrier that protects their mind from the harmful effects of said energy, that makes it possible for their individual ego to form, and that also protects their privacy, so no other Reyvateils, not even the Tower Administrator, can have access to their minds. Given this, neither the Reyvateil herself or the Diver can ever enter the Boundary Gate, and thus it always is kept closed.

The Boundary Gate can be destroyed in order to gain access to the Binary Field of the SH Server to which they are connected, but doing so is only possible in immature Reyvateils. And in the first place, it is desirable to try to find other way to enter the Binary Field if the need ever arises, as destroying the Boundary Gate is almost always a death sentence for the Reyvateil whose Gate was reduced to rubble if there isn't a way to restore the SH_RAM back to a previous state.

Internal Memory Bus of the Tower
An area very far away from the memories and feelings of the conscious of the Reyvateil, and which can never be reached by any part of their minds due to being the Shared Consciousness Fields that all Reyvateils connected to the same SH Server share. It could be said that this β-6D's mind itself, as the place where the minds of the Reyvateils are gathered and that serves as the source of their powers.

Purpose
Divers usually come to the Cosmosphere of a Reyvateil in order to help craft Song Magic as well as trying to improve their relationship with her. Given that during this time the H-Waves forming the mind of the Reyvateil and the Diver are in direct contact, the Diver can easily give more influence to the Reyvateil's mind and cause undulations in her H-Waves, moving her. Whenever the Reyvateil is moved enough, the emotions this caused to sprout in her heart will usually bring a new Song Magic into existence. Additionally, if the Diver manages to cause a powerful enough positive impact in her mind, both will grow spiritually and will become able to proceed into a deeper stratum, this act being known under the name of Paradigm Shift.

False Cosmospheres and Exceptions
It must be noted that neither Shurelia or Tyria possess Cosmospheres. Shurelia was created before it was possible to understand the workings of the human mind and the concept of the Cosmospheres was created, in addition to her using the static memory system known as the HD-Cellophane, so she doesn't have a Cosmosphere due to this. Tyria was created several years after the Cosmospheres were invented and several Reyvateils were produced with them, but due to security reasons, it was decided to give her an HD-Cellophane instead of the D-Cellophane used by Reyvateils at the time, so she lacks a Cosmosphere too. Because of this, Diving into them only sends the Diver to an isolated area of the Binary Field of their corresponding Towers, into which they can deploy virtual reality games. However, even if they behave like Cosmospheres, they are no more than areas of the Binary Field modified to act like this, and receive the name of Mock Cosmospheres.

In the case of Frelia, she does have a proper Cosmosphere due to being the first Reyvateil created with a D-Cellophane, model that was later on copied by the Pureblood β-types. However, given that current Dive Machines are unable to access her SH Server and thus, it is impossible to Dive into her Cosmosphere at the moment, the Divers instead hed redirected to her isolated area of the Binary Field, as it happens with the other Origins.