[ Summary copied from warriorwatchman on the /r/fnaftheories Discord ]

The theory posits there's essentially an intangible network that connects various events through emotions and memories, it's a subspace of the real world, but it's not like some distinct separate layer that coincides with the real world, it's a subspace that's created from the real world 

The memory of real events infects the objects surrounding them, most notably technology, which are able to conduct these memories and output things from them, which just basically means animatronics get haunted, but also things are left with an imprint of the memory, such as the ballpit, or arcade machines, which are the minigames.(for clarification, he's saying the agony of events infect arcades and cause the minigames we see, making them actually a real thing in universe)

This network is a result of the minds and memories of those connected to Freddy's, which all builds off each other. This network would first be established by BV through his intense memories and as a result would basically flow down the network into everything. Many strands build off of what he initialized, and as a result he travels throughout all these newly created subtunnels, making his spirit essentially the embodiment of this subspace, which is the explanation for 4s future references and BVs connections to HD and such, those future references are just meant to establish the channels he travels down to influence the real world through this subspace created by his psyche. 

This notably means that while the real world affects the subspace, the opposite is also true, the subspace affects the real world. The subspace isn't actually a separate realm, it's a realm embedded into the real world, the two are intertwined.
This results in these "agony manifestations", such as the shadows, or the phantoms, or Mike's nightmares, or Jeremy's nightmares(the fnaf 2 dreams), or UCN as a whole. They're mixes of these two worlds, manifestations formed from the two worlds interacting and reverberating amongst each other. This is also how Mike can die in his nightmares, him dying there reverberates to his real body because the two worlds are interlinked.

The conclusion here is that these two worlds are merging, technology is being used to conduct the subspace and incorporate into our world, and the way it's done is through VR and AR spaces. 

But also that there is one epicenter for all of this collision, one spot where all the channels within the subspace and the events of the real world converge, the mimic.