Differing Reality Physics and Portability

After being forced to think about how this all works by Rebecca (whose intellectual honesty I admire even as I mourn for the good old days of sweeping the whole issue under the carpet), I have come to the insight that although treating each reality solely in its own terms has an appealing philosophical purity, it's not actually feasible when travel between them is an everyday event.

I still claim that the in-character situation is massively complex, since there exists no merely four-dimensional intelligence which the Architects cannot befuddle, but to a zeroth approximation the natural laws of a reality can be described as ratings on four axes: Matter, Energy, Biology, and Spirit.

The MEBS Scale

The four axes of the MEBS scale describe how complicated, sophisticated, powerful, or just plain cool of effects are possible with those realms in a particular reality. Although this is roughly correlated with technological (or magical, if you think they're different) advance, MEBS is explicitly not a "tech level" scale: it describes what can be accomplished, not what the natives of that reality or anyone else might have actually accomplished to date. It is perfectly normal to find a civilization that has developed quantum computing (and therefor must be in a reality with at least Energy 6) while still having no idea that contragravity (Energy 3) is even possible.

Each axis runs from 0 to 10, encompassing the scale of what's been seen in Nexus and its suburbs; ratings below what's labelled 0 probably make it impossible for the reality to be interesting enough to connect to Nexus, while ratings above MEBS 10 are either just vanishingly rare or else potential competition for the Architects.


The Matter rating of a reality describes how much useful variation there can be in properties of materials. At low levels, these materials are not very interesting, and are generally found; at higher levels, they can have tremendously exotic properties, and are usually made rather than found in nature.

0Dirt, rocks.
1Leather, bone, wood, sharp rocks, fire
2Raw metals, primitive dyes, pottery, batteries
3Alloys, glass, black powder
4High explosives, aluminum, epoxy, superconductors
5Armor ceramic, liquid crystals, electro*active material
6Vat-based nanotech, polka-dot paint, structural pseudodiamond, room temperature superconductors
7Bonded superdense armor, free-range nanotech
8Freeze-dried isotopes, utility fog
9Industrial neutronium, strange matter
10Quasimatter, negative matter


The Energy scale measures what kinds of energy are available to inhabitants of the reality and how sophisticatedly those energies can be manipulated. This is usually done with clever arrangements of matter, so the two scales are often correlated, but need not be exactly the same and can sometimes be wildly different.

(Note that energy storage is rated on the Matter scale, since it is just magnitude of energy rather than sophistication of use, but obviously a battery is of no use below Energy 2 or 3.)

Simple mechanical and thermal principles (levers, wedges, hot-air balloons, springs) work in all known realities except a few where they are overridden by the effects of overwhelming Spirit (which tends to happen at the level of devices rather than principles); presumably a reality where they did not would be unable to meaningfully participate in Nexus.

0Mechanical and heat only
2Compasses, piezoelectricity
3Electric motors/generators, radio, contragravity
4Transistors, computers, primitive lasers
5Efficient lasers, photonics, artificial gravity
6Quantum computing, fourier optics, reactionless drives
7Free-standing holograms, spy beams, inertia cancellation
8Hyperspace travel, temporal stasis
9Lightspeed teleportation, artificial singularities, hyperwave communication
10Computation bombs, stargates, pocket dimensions


Like Matter and Energy, the Biology scale describes how exciting of effects are possible; unlike them, in some ways it goes as the inverse of complexity: realities with a low Biology rating often have life so complex that no useful changes can be made, while realities with a high Biology rating tend to have more robust, simple, versatile organisms.

Needless to say, many of the devices or techniques given as examples also require appropriate levels of Energy, Matter, or both; the Biology rating determines if it will work once you've built it.

0Giant amoebas, poisons, minimal sapience
1Multicellular life, antibiotics, selective breeding, human-level sapience
2Vertebrates, uppers/downers, superhuman sapience
3Post-vertebrates or enhanced vertebrates, organ transplants, designed drugs
4Hyper-post-vertebrates or massively enhanced vertebrates, simple genetic engineering, artificial organs, regen therapy
5Limited or slow shapeshifters, gene therapy/transform virii, genomes from scratch, brain transplants
6Fast complete shapeshifters, monstrous transformation drugs, brain-computer interfaces
7Self-grafting limbs, novel artificial life forms, braintaping, true defeat of aging
8Life arising in all environments
9Resurrection from tissue samples, drastic bodily transformation
10Any matter can be alive, arbitrary restructing of organisms, nigh-immortality


Different realities call it mana, quintessence, ur-matter, divine providence, dark matter, materia celesti, spontaneous quantum correlation, or any number of other things, and ascribe it (rightly or wrongly) to an equal range of sources or causes, but it seems that in the eyes of the Architects, it's all the same. The thing generically called spirit fairly uniformly has an affinity for complexity or sapience, but how much actual effect it can have on minds or anything else depends on the Spirit rating of the reality.

The Spirit rating doesn't indicate how efficient spirit is at affecting the material world; using more doesn't normally get you the effects of a higher level. Rather, it describes what sort of effects are possible, or on what level spirit affects matter and energy. At 0, spirit may accumulate around sophonts, but doesn't have any significant effect; at low levels, spirit only interacts with sapient minds; at higher levels, it can produce gross physical effects. At the top of the scale, matter and energy, though seemingly arranged in the normal sorts of patterns to form people, landscapes, and so forth, dances to the tune of spirit: prophecies *will* come true, third sons always rescue the beautiful dragon from the ravening princess, and the sun really is a giant beetle riding a taxicab across the sky.

A note on terminology: Although many belief systems conflate 'soul' in the sense of emotion with 'soul' in the sense of ego continuity independent of physical existence, the stable patterns described below are only souls in the second sense; most sophonts do not lose their capacity for emotion upon entering a zone with a Spirit rating below X (although some native to a high-Spirit zone might suffer that or other psychological effects).

0Spirit is unconnected to anything else
1Spirit affects only minds (telepathy, mental illusions)
2Spirit can form stable duplicates of mental patterns (immortal souls, psychic imprints)
3Spirit can sense but not affect matter/energy (clairvoyance, possibility-based precognition, other sensory powers)
4Spirit can affect chance, produce nonthermodynamic effects (luck-based magic, energy drawn from ambient heat)
5Spirit capable of nonlocal effects (transportation or rearrangement of mass/energy)
6Spirit can create matter and energy at existing MEB rating (fireball, conjured objects or beings)
7Spirit can substitute for matter or energy, effectively increasing MEB (shapeshifters, regeneration, magical materials or forces)
8Spirit as important as energy/matter (world of fairy-tale/mythic logic)
9Spirit capable of acausal effects (time travel, true prophecy, FTL travel)
10Spirit dominates (omnipotent omniscient divinity, dreamworlds)

Interreality Travel

All Nexans know that some interfaces translate anyone and anything passing through them into a form more thematically suited to the reality on the other side. What isn't as widely realized is that *all* interfaces do this in a more or less noticeable way. They have to; you can't just move something that exists according to one set of physical laws to a place where different (possibly *much* different) laws apply and expect to have anything except undifferentiated mass-energy at the destination. In general, all interfaces into a zone follow the same transformation rules, so the transformation can be thought of as belonging to the zone rather than to any interface; the exceptions are rare enough to enumerate.

Each reality has its own MEBS rating for its own physical laws (typically pretty high in Matter, Energy, and Biology; Spirit is often low but varies more), which may or may not be higher than the natives can fully exploit, but also has a MEBS rating for what can be imported. The import restrictions are usually about the level that the locals have actually achieved, perhaps with an extra caveat to more closely match their development ("Energy 6 but no lasers", "Matter 2 but with gunpowder"), but may be lower, in which case visitors are at significant disadvantage, or higher, which leads to the natives being conquered a lot. Obviously the importation restrictions cannot be meaningfully higher than the native rating of the reality: if there's no such thing as hyperspace, there's nothing for the interface to translate a hyperdrive into, even if it's willing.

Widgets that can't function under the import limits might be transformed into the nearest local equivalent (eg, handgun to crossbow); more often they just become inert objects, puddles, clouds, or whatever of equivalent mass and similar mechanical properties. Partially-limited widgets keep any functions that pass the import limits: a gun taken to someplace where gunpowder doesn't work still has all its moving parts and can loaded and unloaded and dry-fired and such; it just won't go off.

A widget so transformed retains its original nature, encoded in some unknown way, so that no matter how many realities it's taken through as an inert lump, and no matter how grotesquely it exceeds the import limits of those realities, if it's taken home or someplace else where its full glory can be displayed, it returns to its original form.

Living creatures are transformed to meet the limit of the Biology rating, which may suppress abilities gained through biological engineering like a supersoldier's Regeneration. However, if the transformation would make the creature not alive, or if no reasonable transformation is possible (as with a vertebrate entering a Biology 0 reality), the creature instead becomes inert, like a nonfunctional widget.

Most interfaces will not transform a creature to withstand adverse environmental conditions (atmosphere, temperature, gravity) in the destination reality; if the traveller can't survive, or her life support gear is trashed by the interface, tough luck.

Cyborgs or otherwise artificially augmented people whose augmentation won't cross an interface and who would die because of it are transformed back to some "natural" state, which usually negates the special abilities but lets them function otherwise. If the augmentation is required to keep the traveller's natural condition from killing her, that's just too bad.

Spirit-based devices, like other widgets, are usually made inert by interfaces that don't support them. Continuing spirit effects attached to some object or person are likewise negated, as though they were functions of a spirit-based device whose other functions might or might not be affected. The ability to produce spirit-based effects is usually suppressed by entering a reality of insufficient Spirit rating, but in some cases such effects might still be possible with more effort or side effects or some such (eg, a Spirit 7 telekinesis power used in a Spirit 5 reality might still work, but since spirit cannot produce energy from nothing at level 5, the energy would have to come from the telekinetic's person, or some source in the environment). A spirit effect produced at range from a reality that works will generally not cross an interface of lower Spirit rating, even if the effect could be generated in the reality where the target is.

Spirit-based creatures which have no physical body are usually transformed into small inert objects in realities they can't enter; spirit-based creatures which animate physical bodies are treated much like spirit-based devices, except they may continue to function in some cases with the same restrictions and consequences as new spirit effects.

Variable Portability

Nexus being what it is, there is a significant demand for items or powers that are more portable than what everyone else has, and entrepreneurs willing to claim to fill that demand. For those who value repeat business, there are two main routes to portability.

First, widgets can be designed and built using the facilities available in a reality of high MEBS rating but to function at a much lower rating: clever design can get you pretty far even with low-grade materials, even if it won't be as sleek and wonderful as with great materials. The same principle applies to spirit-based devices: the results of a high Spirit rating effect can often be achieved with effects of a lower rating plus cleverness and time. This generally lets a widget function at a rating 1 less than it would normally require, but not as well as if it were designed normally. It also is usually clunkier, has less capacity, is more fragile, or is otherwise lacking.

Second, devices can be designed with redundant systems, so that instead of falling over dead when entering a zone of lower rating, they degrade somewhat gracefully. The redundant systems take up more space and require more maintenance, of course, but it can be worth it to have both portability and good performance where available.

These options can be combined, of course, which gets you the benefits and disadvantages of both, and plenty of extra cost as well.

Innate powers are not as flexible, unfortunately. Particularly versatile powers can compensate by using lower-rating methods to achieve somewhat better effects, but fixed powers either work, work with side effects, or don't work, and there's not a huge amount that can be done about that.

There are also instances of decreased portability: some particular technologies or powers or whatever are so dependent on the specifics of their home reality that they can't function in other realities of the same rating. Usually they can function at some higher rating, though, so count as that many levels higher for portabilities purposes.

This file was last modified at 1646 on 01May01 by trip@idiom.com.