Difference between revisions of "Category:Observerspace"
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The Observerspace approach is a literal approach to theoretical physics. It can be considered as a deliberately simplistic and naiive approach that strips away layers of interpretation to deal, as far as possible, with raw data.
Value of observerspace arguments
Observerspace logic is useful when we have an existing entrenched theory, and need some method of reexamining a problem fresh in terms of fundamental physics, while leaving behind our taught preconceptions and belief systems that can colour our judgement and prevent us from seeing fundamental relationships that we "know" are wrong, even when they correspond to objective physical reality.
Observerspace arguments can short-circuit our education and professional training, and our social and psychological conditioning.
Observerspace arguments can be used as a fact-based questioning exercise that is most useful when existing sophisticated approaches have met a dead end, and are similar to the standard scene in detective television seres where, stumped by an unsolvable crime, the team gather around a whiteboard and start listing the actual unarguble facts of a case. In theoretical physics, observerspace arguments say, "Let's forget about what we think we know about what is really happening here, and instead focus on:"
- what did our detectors actually register?
- what did our sensors actually report?
- what would a dumb "stills" camera actually record in this situation?
- what would a film camera show us?
- If we were "ignorant" and didn't know any better, how else might we (mistakenly) interpret this raw data?
Observerspace arguments often seem hopelessly wrong ... and this is a major part of their importance - they let us look at alternative interpretations that would normally seem so wrong-headed that they'd be considered eligible for immediate rejection without examination.
Observerspace as as a test for consistency
We can also attempt to apply the concept of observerspace as a principle, as the idea that reality must not only //be// consistent, it must be //seen// to be consistent ... because what we see (and record using our hardware) is, in a sense the real physics of a situation. The laws of how one atom reacts to forces associated with another, are at least partly the laws of how one atom sees and feels the presence of the other. Local causality is arguably local apparent causality - if a body reacts physically to what is //sees// to be an event, then for that body, the event is real.
Limitations of observerspace logic
Observerspace logic works when all the data concerning the physics being watched is available to the observer. The concept starts to break down in cases where information is not reaching the watcher, such as when we have observational gravitational or cosmological horizons. In these cases, the observer is reduced to the equivalent of trying to create a complete and deterministic model of what is happening in a card game, when not all the cards can be seen - the observer is forced to fall back on interpretation and statistical descriptions, and create structures where not all of the critical data can be verified.
While observerspace logic can be powerful as a tool for bypassing existing belief systems and isolating new principles and laws, the consistent operation of those laws in a new resulting theory often requires us to revert to interpretation, and to the projection of new belief systems onto the (incomplete) available data.
Observerspace and logical positivism
Observerspace and Einstein's general theory
Einstein's general theory has a mix of observerspace and non-observerspace logic. An advanced general theory would tend to use observerspace arguments to point out that cosmological horizons and gravitational horizons look like each other, and therefore by default should be treated similarly - since cosmological horizons unavoidably fluctuate and radiate, gravitational horizons should be expected to do the same. When we then found that an SR-based GR didn't show this equivalence, we might then ask whether this meant that founding GR on SR was a bad idea.
Observerspace arguments for the apparent, photographable lengths of approaching and receding objects lead to arguments for the existence of gravitoelectromagnetic effects between relatively-moving bodies, additional equivalence principles, and a different form of general theory based on an acoustic metric.
Where Einstein's general theory does apply observerspace logic is in its adoption of Mach's principle (downgraded in GR1960), in Einstein's recognition that a free-falling observer doesn't feel the existence of a background gravitational gradient*[ignoring tidal forces], making the existence of a gravitational field in a region fully observer-dependent, and in its use of strict observerspace causality for describing trans-horizon physics.
Under GR1960, visible effect is not allowed to precede visible effect. Although if we hover near a black hole, the deduced time at which an infalling body crosses the hole's r=2M surface may only be a few hours or minutes into our future, the time at which is is seen to reach the surface lies arbitrarily or infinitely far into our future (we never see it actually reach the surface). events generated by the object inside r=2M are then assigned to our more than infinitely distant' future, in other words, they effectively do not exist in our universe. If visible effect is not allowed to precede visible cause, then by definition no signals generated within r=2M can influence the external physics (in the absence of time travel). Even if the infallen object attempts to create a gravitational disturbance that changes the position of the nearest section of effective horizon, under GR1960, this disturbance is not allowed to make the effective horizon fluctuate.
Although admirable, this strict adherence to distant observerspace causality is not actually a feature of our universe, since it doesn't apply in the cosmological horizon case - for cosmological horizons, an object behind the horizon can theoretically create a disturbance that result sin the effective horizon fluctuating and revealing events that wouldn't otherwise be expected to be visible (perhaps even including the event that caused the fluctuation).
With a cosmological horizon, and with acoustic horizons in general, "the man behind the curtain" is allowed to make their presence indirectly visible by modifying the curtain shape, and perhaps even lifting a corner of the curtain to reveal a foot or their entire body.
In summary, an acoustic general theory applies observerspace more thoroughly than GR1960, generating an acoustic metric) ... except in the case of horizon causality, where GR1960 applies strict observerspace logic, and an acoustic general theory predicts that strictly ordered apparent causality breaks down.
"literalist", "instrumentationalist" or "experiential" interpretation of physical phenomenology, where what appears to be happening is taken as physical reality ("what you see is what is there", "logical positivism").
"Observer space" can also refer to a coordinate system designed to describe reality as it might be seen for a particular observer or class of observer, (e.g.: optical coordinates). The The approach attempts to model the universe using only physical observables, with more emphasis on describing the immediate phenomena reported by "instrumentation" and less on deriving deeper underlying causes - reality as it is seen to be, rather than how it is deduced to be.
Pure vs. interpreted data
Although this sort of literalist approach can sometimes seem perverse, the way that an object is "seen" by an observer relates to the way that it is "seen" by the other bodies with which it interacts. The physics of the object's interactions is therefore (in a sense) the physics of "what it looks like", and of how the other objects with which it interacts are "seen" by it in turn. In this sense, "optical illusions" can be considered to be a legitimate part of physical reality, and visual artefacts can play a legitimate role in determining the behaviour of real physical laws, such as the laws concerning electromagnetic and gravitational fields.
The advantage of the observerspace approach is that it sometimes allows "visible" physics behaviour to be modeled directly without requiring a deeper underlying paradigm - this can let research programmes continue even when physics is "stalled" by shortcoming in existing interpretationalist paradigms, that cannot cope with some new aspect of physics theory.
The disadvantage of the observerspace approach is that sometimes invoking deeper principles allows behaviour to be described more efficiently, "surface physics" can sometimes be more complex and more difficult to understand, and does not always obviously seem to be obeying basic laws over small scales (such as conventional causality, or strict conservation laws). If a distant star moves behind a high-gravity object and is seen to split into a number of separate objects due to the gravitational lensing of its image, then although we should in theory be able to construct a description in which it really does break apart and reform in a strange way involving observer dependent reality and retrograde causality, it is simpler to say that the underlying behaviour is fixed ("the star does not split"), and to explain the apparent behaviour by the effect of gravity on light.
Observerspace and Mach's Principle
Observerspace and special relativity
Observerspace and the Membrane paradigm
Observerspace and gravity Observerspace
Pages in category "Observerspace"
The following 5 pages are in this category, out of 5 total.