In the year 3918 AD, Dr. Max Payne, later hailed as the "Father of Dimensional Space Theory" but known in his time as a "madman," validated the theoretical framework of "Dimensional Parallelism" and proposed the existence of "Parallel Spaces." However, his ideas were largely dismissed by the majority at the time.
It wasn't until 55 years later, in 3973 AD, through the relentless efforts of Dr. Payne's successors, that the first parallel space was discovered. This breakthrough gradually led humanity to recognize the feasibility of "Dimensional Space Theory" and the boundless potential for spatial expansion.
By the bicentennial of Dr. Payne's proposal, after countless expeditions, humanity had identified six alternate-dimensional spaces with life forms. In keeping with humanity's anthropocentric tradition, the space where humans resided was named the "First Space," while the other six were sequentially designated as the Second Space, Third Space, Fourth Space, and so forth, in order of discovery.
### **The Second Space**
Strictly speaking, the Second Space is not a complete space. When first discovered by the Sigrynama Space Research Institute, it was thought to be a spatial fault between dimensions rather than an actual dimension. The reason was its planar nature—unlike the First Space, which comprises stars, planets, satellites, and vast galaxies, the Second Space exists as a flat expanse without vertical dimensions. Though its "vertical" expanse spans billions of kilometers, this is negligible compared to the immeasurable depths of the First Space.
What ultimately classified it as a separate dimension was its striking similarity to Earth's environment. The Second Space features boundless plains, stretching infinitely, with mountains, rivers, and dynamic weather patterns. However, its sky is adorned not by a sun, moon, or stars but by radiant energy halos that shimmer like rainbows and crystalline diamonds, casting light over the land.
The most astonishing discovery was the existence of life forms, many resembling Earth's flora and fauna. Due to the unique conditions of this dimension, its organisms exhibit extraordinary abilities. Some are so powerful that they can resist advanced human weaponry. Three years after its discovery, exploration teams identified large settlements of intelligent lifeforms in the southeastern region, 1.67 billion kilometers from the entry point. Sixteen such settlements were found, covering a total area of over 60 billion square kilometers, with a combined population of roughly 400 million across various species.
For religious believers, the Second Space resembled the mythical heavens, and it became colloquially known as the "Celestial Realm."
In 3998 AD, the **"Second Dimensional Space Protection Act"**, commonly referred to as the **"Celestial Law"**, was passed by the Dimensional Management Bureau. This law strictly prohibited disturbing the native inhabitants of the Celestial Realm or revealing humanity's extraterrestrial origins.
### **The Third Space**
The Third Space remains the most enigmatic and incomprehensible to humanity, as it lacks the concept of "time." Scientific research has confirmed the existence of life, but these lifeforms exist in forms beyond human understanding. Due to the disparity in the nature of existence between the Third Space's entities and human life, meaningful communication remains impossible.
This unique characteristic earned it the moniker **"Chaos Dimension"**, and it remains the least understood of all discovered dimensions.
### **The Fourth Space**
The Fourth Space brought humanity its most painful lessons. Structurally similar to the First Space, its lifeforms, however, are entirely distinct. Within its star system, there are 88 planets, nearly all teeming with robust and astonishingly powerful life.
The organisms in this space possess extraordinary individual capabilities. Some exceptional creatures can traverse the cosmos unaided, moving freely between planets. Despite their strength, these lifeforms have not established complex social systems, remaining in tribal states.
Upon humanity's initial exploration, aggressive species launched violent attacks, resulting in the total annihilation of the expedition team. The invaders soon breached the First Space through the dimensional entry point, and humanity paid a heavy price to repel them. Without the subsequent discovery of the Fifth Space, humanity might have faced extinction due to repeated invasions.
The Fourth Space has since been known as the **"Demonic Realm"**, with substantial military forces stationed at its entry point to defend against its hostile inhabitants.
### **The Fifth Space**
Though humanity has identified countless dimensional spaces, only those with evident signs of life have been closely studied. The Fifth Space is an exception.
This dimension shows no signs of life but contains remnants of an advanced civilization. Studies suggest that this civilization once spanned dozens of star systems, achieving remarkable technological advancements before succumbing to decline, war, or an unknown catastrophe.
Research indicates this civilization's technological development predates humanity's by over a billion years. The discovery of the Fifth Space allowed humanity to adopt ancient technologies, significantly enhancing its own capabilities. These advancements played a crucial role in defeating repeated invasions from the Demonic Realm and ushered in a new era of rapid progress.
Known colloquially as the **"Future Realm"** or **"Phantom Dimension"**, the Fifth Space has become a symbol of hope and technological inspiration.
### **The Sixth and Seventh Spaces**
The Sixth and Seventh Spaces were discovered simultaneously. In fact, the Seventh Space was identified through an interface within the Sixth Space.
The Sixth Space is home to lifeforms with development levels akin to humanity's prehistoric era. However, the Seventh Space harbors a civilization slightly more advanced than humanity's and has long established contact with the Sixth Space. While the Seventh Space civilization has influenced the Sixth, it has maintained a policy of limited interference.
To date, humanity has yet to venture into the Seventh Space.