A spatial anomaly or spacetime anomaly is a region of spacetime where the geometry of space becomes obviously non-Euclidean, and gravitational effects cannot be treated as a force between, or acceleration produced by, massive objects. The term is not a technical one and as such lacks a rigorous definition, but many starfleets' scientific departments define a spatial anomaly as being a region where gravitational effects exist that cannot be described using the formalism of gravitoelectromagnetism, either qualitatively, or quantitatively with some higher-order corrections. They may sometimes, but do not always, exclude hyperspatial anomalies that are restricted to hyperspace.
Colloquially, gravitational lensing and gravitational waves may even be referred to as "anomalies", although these are in fact ubiquitous phenomena. While spatial anomalies typically involve temporal disturbances, they are not to be confused with temporal anomalies, which are timeline discontinuities and intersections, although temporal anomalies are often classified as a category of spatial anomaly.
Types of anomaly Edit
Dark matter Edit
One of the key features of gravitation is that every change in geometry can be traced back to a source, and depends purely on the source's energy, momentum, and stress (in gravitoelectromagnetism, the effect of stress is negligible, while Newtonian gravity also ignores the effect of momentum). This leads to a set of spatial anomalies which involve gravitational effects (potentially including other anomalies such as topology changes) that seem to lack an appropriate source. The undetected source is known as "dark matter", and while many varieties exist, most of it is caused by hypermatter, while some localised occurancies are the result of Essence. Besides its gravitational impact, hypermatter can become viscous and form hyperspace fog, which inhibits the movement of spaceships and the propagation of signals in hyperspace, hence it is of particular interest to starfleets.
Thick clouds of hyperspace fog can lead to "subspace storms", where hypermatter leaks into realspace and forms high-energy plasma along with a foam of microscopic wormholes. These wormholes further heat the plasma as they collapse, allowing the subspace storm to be self-sustaining until either the hypermatter or plasma is no longer sufficiently dense to continue the process. Hyperspace fog can be triggered into forming a storm by the presence of an active hyperdrive, and the ionising radiation emitted by storms is particularly dangerous when they manifest inside starships.
Black holes Edit
Even in the simplest nonrelativistic description of gravitation, Newtonian gravity, "dark stars" exist where the gravitational pull is so great that even light cannot escape. A key part of this is the concept that a certain amount of kinetic energy is required for an object to escape a celestial body's gravity, and if all of this energy were put into the object at once, it would have a particular speed known as the "escape velocity". For a dark star, this escape velocity is greather than or equal to the speed of light. However, it would still be possible to leave the dark star by continuous acceleration, in the same way that spacecraft can leave planetary orbit without reaching the planet's escape velocity.
The same is not true for their real-world equivalents, black holes. For these, the dark star's escape velocity corresponds to the existence of an event horizon, in which the arrow of time itself is bent so much that time and space effectively swap places, such that travel into the future is identical to movement towards the centre of mass. Escape really does require the ability to travel faster than light, or more generally backwards in time. This feature marks the black hole, an otherwise simple (albeit extreme) gravitating object, as a naturally-occuring spatial anomaly. Extremely high-amplitude gravitational waves, known as thunderbolts, also possess event horizons.
Topology changes Edit
A more drastic departure from gravitoelectromagnetism is where not only the geometry but also the topology of spacetime is altered, connecting otherwise seperate parts of spacetime together. This is a very large group of phenomena, and many different schemes of subdividing it exist.
By far the most relevant topology changes to a spacefaring society are wormholes, warp bubbles, and other hyperspatial structures that allow for faster-than-light and interuniversal travel; non-orientable wormholes provide access to hyperspace. These are somewhat like the gravitationally-repulsive counterpart to a black hole in terms of how they alter the arrow of time. Although far less common, similar structures also allow for travel backwards and forwards in time, to pocket universes, and to other Planes of Existence. Uncontrolled topology of this type can be highly risky, both as a result of leading to dangerous locations and due to the possibility of destructive collapse.
Some topological defects in scalar fields also impact the topology of space via gravity, particularly cosmic strings. The total interior angle around a cosmic string is, unlike that of a Euclidean circle, less than 360 degrees. Despite this, these strings are no more harmful than any other celestial object unless collided with, although they can emit gravitational radiation and decay (especially if they form loops).
Escher space occurs where the space is twisted smoothly back on itself into the shape of an impossible objects. This is a common occurance in hyperspace due to the quantum-chaotic folding of the realspace brane, but can also be achieved in realspace either as a result of subspace storms or with sufficient stabilisation mechanisms. Large Escher spaces pose a risk in military situations, as ranged weapons will tend to veer off course and may lead to friendly fire, while smaller Escher spaces pose a signficant risk of injury due to intense spatial warping.
Metric bubbles Edit
Metric bubbles (not to be confused with warp bubbles, which are far simpler structures) are a class of hyperspatial technologies that, like wormholes, utilise gravitationally-repulsive matter; they function as gravitational Faraday cages to prevent gravitational influences outside of the bubble from affecting the inside, and vice versa. While all metric bubbles are artificial, they do not always need a power source and so can become stable fixtures of the environment.
Time dilation fields are regions of space where a high density of dark matter is used to induce gravitational time dilation, while a metric bubble surrounds it to ensure that this high density does not result in intense gravitational fields outside. The total time dilation is due to the difference in mass density between the inside and the outside of the bubble, while density gradients can induce gravitational forces within the bubble itself.
Metric shields are a special type of metric bubble that function as impenetrable barriers to the worldlines of all particles. Most of these are purely defensive in nature, but nightshade traps are potentially deadly devices which can be deployed like a mine and - superficially similar to an event horizon - allow objects to enter but prevent them from escaping.
Hyperspace unfolding Edit
In many ways, the whole of hyperspace can be thought of as a single universe-spanning spatial anomaly, but due to its near-omnipresence it is never classified as such. Instead, normal hyperspace is commonly treated as the default four-dimensional background space on which all of the universe's fields and forces live, which means that it is disruptions of this background that are considered to be anomalous.
The most severe disruption of this kind is when the microscopic folds of a region on the realspace brane are flattened out, thereby ensuring that there is no hyperspatial shortcut possible between points within this region, or (if the region fully encloses part of the universe) between the two sides of the region. It can also be used to prevent access to hypermatter; it is known to have been achieved for this purpose by Apalos using hypermatter explosions to create a spherical unfolded region. These unfoldings are unstable; the strength of the shock wave decreases with distance until it fails to induce further unfolding, at which point hyperspace refolds inwards from the outside at the speed of light. It is suspected that similar techniques are also the key to non-Chronoscopic time travel.
On a larger scale, Ultraterrestrial technology is able to produce unfoldings for long-term denial of access to a region except via specific wormholes. These most famously take the form of galactic barriers, such as found in the Cyrandia Cluster, which are shaped as hollow shells with radii hundreds of times greater than their thickness (itself on the order of kiloparsecs) and are stable over billions of years.
More immediately destructive than a complete unfolding of hyperspace is a refolding following a partial unfolding, which leads to "subspace compression", whereby hypermatter is forced out of hyperspace in artificial subspace storms. This can be achieved either by using modified faster-than-light drives or by sending thunderbolts through hyperspace. This is not to be confused with controlled refolding of the realspace brane, which is used to create pocket universes with different low-energy physics (coupling constants or particle content), although this can also be weaponised. For example, the Delpha Coalition of Planets sometimes utilises "warp vacua", in which a warp bubble encases a target and then the couplings in its interior are changed; a common tactic is to reduce the strength of electric charge so as to cause chemical bonds to break apart, turning solid matter into plasma.
- This page was created after Wormulon commented that the SporeWiki fiction universe lacked diversity in spatial anomalies, and Ghelæ responded that a definition of "spatial anomaly" was itself lacking. Nearly seven weeks later, Ghelæ remembered the conversation and started the page.