From my understanding, the universe we see is from light arriving minutes to billions of years later than the actual state of whatever object one is looking at. So are there any techniques that allow different imaging than a traditional photograph to be viewed of the universe or are any such techniques being developed currently to allow a more real-time approach?
Interesting question. Since nearby objects are nearly “real time” let’s consider only distant galaxies. Furthermore let’s consider galaxies that are on the Hubble flow - that is, they are receding from us according to Hubble’s law. Such distant galaxies are not only receding from us but exist in real time (“now”) along a hypersurface. The light we view is from when the universe was younger (that is, nearer the big bang in time). So essentially we are viewing the past of these galaxies coming to us at the speed of light. Where are these galaxies “now” - in real time? They exist on a hypersurface that is causally disconnected from us by the number of light years away they are “now”. Not only that, they are receding from us at a rate proportional to there distance- thus they will continue to get farther and farther away (even if the expansion of the universe is not “accelerating”).
Unless the laws of special relativity are somehow bypassed, this is the accepted view of our view of the universe. Is there any possibility of real-time causal contact? This would require instantaneous action at a distance (nonlocality). This would require transport of information at faster than the speed of light. Einstein rejected such possibility (and all evidence agrees). Einstein also developed what is known as the EPR paradox. This is a quantum mechanical thought experiment which seems to defy the classical principle of locality. As you may know, such quantum “entanglement” has actually been observed in the laboratory, defying Einstein’s own expectations. This does not mean communication is passed faster then the speed of light, but it does mean there are always new surprises that can possibly guide us to new understandings locality and the speed of light.
Finally, I’ll conjecture, that the possibilities of discovering higher spacial dimensions may lead to accessing nonlocal phenomena on the macroscopic scale. A hyperdimension could lead to other ways to navigate the universe. This is highly speculative but I would have an open mind about these things. Otherwise, the laws of relativity will only allow us to view the distant past of distant galaxies - forever nonlocal, not in real time.
I agree fully with Paul. Our current knowledge about space and time does not allow us to see distant Universe as it it is just now. This makes also so difficult to communicate with any other cosmic intelligence if it exists far away and a liftime of such an intelligence is limited (our first signs of high level technology have reached only a very small amount of neighboring stars in our Galaxy). Of course one could speculate about different tricks to overcome such a limitation ( a la Star Gate) but only on a very shaky ground.
In the simplest of terms, aren't we properly viewing all light, near and far, in 'real time' - as photons arrive in our detectors? Beyond that, all information about the emitting objects' properties, the emission date/universe age, propagation distance, etc., derived and inferred from very detailed analyses of the characteristics of detected photons? In this sense, there is no more 'realistic' or timely view of the universe available.
I think that assembling a 'contemporaneous' view the objects in the local group, for example, would be very interesting, but would require the compilation a continuous observational history database for all selected objects of a duration that includes the propagation distance to the most distant object.
On the other hand, observations of distant, large scale structures such as galaxy clusters do offer an approximately contemporaneous view of all constituent objects, relative to the Earth...
It is possible to develop such techniques to allow a more real-time approach, especially if you consider recent advances in scientific visualization. Consider for instance, the development of a graphical interface which models the solar system in future and past times, this can be done very accurately. Your 'view' of the solar system will be based on past information, and depending on the exactness of your understanding of the physical processes involved may even involve macroscopic features (e.g. evolution of landscape features, oceans, climate). With more computing power, advanced modelling etc. your 'resolution' can be increased. This line of thought can of course be extended to the local galaxy and further. So, even though you cannot physically move in time at this stage, you can visually via models and computer visualization start to move backwards and forwards. It is being done everyday with weather predictions etc. at local and limited scale. Of course there will be a limit to the realness of this peek into the near real-timeness of the universe, but I am sure you can see the possibilities!
Ludwig,
"It is being done everyday with weather predictions etc. at local and limited scale."
The issue is that collection of historical data with daily observational frequencies is quite feasible. However, historical collection of observational data that varies over cosmological frequency scales is highly problematic. In a universe that varies over scales of billions of years, collection of precise observational data is quite limited. While we make observations 10 billion year old light emissions from ancient (distant galaxies), we cannot reasonably accumulate such observations over durations of even millions of years - due primarily to limitations in the duration of unman life, technological societies and even mechanical devices.
The only possibility for simulating such long duration observational data would be in the accumulation of model prediction results - which can neither be verified not validated over similar durations. I can only hope that you can comprehend the limitations of such methods!
James, modelling and graphical visualization will of course be limited, and as you rightly mention, validation will be difficult due to the time periods involved. It is however an interesting way to explore the history and future of the universe. As example, using space geodetic techniques, one can already model, and test, the predicted position of satellites in the gravity field of Earth, both back in time and into the future, to a fairly high level of accuracy. This of course already involves many facets of science as the orbits are affected by spacetime curvature, changing mass distributions on Earth, effects of the planets, Moon and Sun etc. Similarly, one can model ocean levels etc. It is already difficult and complicated at a local level, so at larger scales it will be very difficult with huge complexity. I am currently writing software to model the solar system as part of a lunar laser ranging data analysis package, and the distance to the Moon must be accurate at the cm level when all modelling and data has been incorporated. At this scale it is already quite complex, but can be checked by comparison with historical events and measurements. Of course only for a relatively small period compared to the history of the solar system. So, looking back and forward in time is 'possible' within limits of what we know accurately enough, software and computational limits etc. It is the only way of doing this at the moment however.
Ludwig,
Thanks for reminding me - variations that may occur of periods of days to years are certainly feasible and quite worthwhile, especially if measurements can be performed at more useful frequencies I was involved for years in tracking and analyzing the performance delivered by overnight package delivery services. Improving service delivery by tracking and evaluating historical factors that affect measurable performance if quite feasible and productive.
The issues involved with the original question occur of measurement intervals of many years, for example, even if useful proxy data can be substituted for actual measurements...
Quantum theory is a non-local theory; this opens the possiblitity that a future quantum gravity theory may disclose to us some non-local global aspects of the universe that could change simultaneously throughout the universe.
Quantum theory is a non-local theory; this opens the possiblitity that a future quantum gravity theory may disclose to us some non-local global aspects of the universe that could change simultaneously throughout the universe.
Louis,
Haven't conditions indicating non-local action been so far limited to the states of quantum particles? Is there any reason to expect that non-locality could apply to macro-scale objects?
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