The Universe As Hologram 532
Several readers sent in news of theoretical work bolstering the proposition that the universe may be a hologram. The story begins at the German experiment GEO600, a laser inteferometer looking for gravity waves. For years, researchers there have been locating and eliminating sources of interference and noise from the experiment (they have not yet seen a gravity wave). For months they have been puzzling over a source of noise they could not explain. Then Craig Hogan, a Fermilab physicist, approached them with a possible answer: that GEO600 may have stumbled upon a fundamental limit where space-time stops behaving like a smooth continuum and instead dissolves into "grains." The "holographic principle" suggests that the universe at small scales would be "blurry," its smallest features far larger than Planck scale, and possibly accessible to current technology such as the GEO600. The holographic principle, if borne out, could help distinguish among competing theories of quantum gravity, but "We think it's at least a year too early to get excited," the lead GEO600 scientist said.
Flatland! (Score:5, Informative)
Re:Plato (Score:3, Informative)
Physics is a subset of philosophy.
No, it's really not.
If you can't tie them together, you've missed something.
What you're missing is the fundamental difference between philosophy and science (including physics.) Philosophy starts with axioms. Science starts with observations. From there on out, the logical reasoning processes of philosophers and scientists are very similar, but the fact that axioms are not subject to modification based on observation makes the results of the fields entirely different.
Re:Okay... (Score:5, Informative)
You might be right, but your explanation is not what I understood from the article (but translating dense physics-speak isn't my forte either;-)). What I understood from it is that they've still not been able to measure gravity waves, so we still don't know if gravity behaves like a particle or not. What they're saying, is that space and time might be grainy, and even more grainy than was previously thought and possibly even so grainy that it renders our current attempt of measuring gravity waves futile.
So it's not about gravity being discrete, it's about space and time being discrete, which shows up as a jitter-like noise in the gravity-wave measuring experiment.
Re:Flatland! (Score:1, Informative)
And now: the amazing Karma-Whoring AC presents:
Edwin A. Abbot's _Flatland_ [librivox.org] in audiobook form, thanks to the nice volunteers at Librivox.org.
Re:Black holes (Score:2, Informative)
Book: The Holographic Universe - Michael Talbot (Score:2, Informative)
MUST READ!
Amazon Link Here [amazon.com]
Re:Plato (Score:5, Informative)
Science as we know it today was pretty much invented by Sir Francis Bacon, a philosopher. It unifies large swaths of epistemology and ontology, thereby rendering much of the field of philosophy entirely obsolete. That the vast majority of so-called philosophers haven't figured this out after 400+ years is one of my largest peeves with academia because, as a direct result of their masturbatory inertia, philosophy has been pushed into an intellectual corner.
So I don't blame you for not understanding that all science is properly a subset of philosophy. Most philosophy professors I've met don't really understand that either. :(
Re:Anti-science (Score:4, Informative)
> Does this sound to anyone a little like the argument for intelligent design?
No.
Take a look at one of the earlier papers on the holographic hypothesis here [arxiv.org]. It comes about, not because some physicist has simply thought "what happens if the universe is a giant hologram". It's implicit, in an incredibly surprising and beautiful way, in general relativity, a well tested physical model.
Hints can also been seen in a bunch of other independent physical results like the Bekenstein bound [wikipedia.org] which point towards the 'granularity' of the 2D surface.
Nobody's copping out. People aren't even making up that much new stuff. They're working out the details of what's already contained within existing (and in some cases, well tested) physical theories.
It's probably worth remembering that for every press release made by a physics department there are probably years of work and thought by multiple physicists.
Re:finite-resolution != hologram (Score:1, Informative)
It's not 'The universe may have a finite resolution' (quantum theory has said that for around 100 years now), but that the resolution is so large. Quantum theory predicts a resolution several orders of magnitude smaller.
What they are saying is that the unexpectedly large resolution is because this universe is a 'hologram' of sorts, and that the edge that the hologram is on has the resolution predicted by quantum theory. Therefore our universe (which is larger than it's holographic source) has a resolution that is larger, because there can't be more data in our universe than is on the holographic source.
Scientific American said about it in 2003 (Score:3, Informative)
I remember reading about the same proposition in a Scientific American article about 3 years ago (I used to read my national edition and there is a lag). However, they were basing the proposition on the analysis of the thermodynamical properties of black holes. Apparently the maximum entropy of a system is determined by the surface area of a sphere that encloses it. Above this limit the matter collapses into a black hole, which has an entropy proportional to its surface area.
http://www.sciam.com/article.cfm?id=information-in-the-hologr-2003-08 [sciam.com]
Re:This reminds me of a book... (Score:3, Informative)
And John G. Cramer has an article here [washington.edu] (and in the December issue of Analog, if anyone has that and hasn't read it yet). This is a very cool theory, indeed, and I'm glad to see it getting more mainstream attention.
Re:Flatland! (Score:4, Informative)
Or download:
http://www.gutenberg.org/etext/97
Re:Alrighty then (Score:4, Informative)
You don't need glasses to view a hologram. Unlike a stereoscopic film with two almost identical pictures, a transmission hologram (we learned about it in an undergrad physics class in college) is a single image that looks like nothing but an interference pattern, which is exactly what it is. When laser light is passed through a lens so that it is not a straight narrow beam, but gets wider as it gets more distant, the image appears in true 3-D on the film. If you move to the side you can see around objects in the picture.
To make one of these, you need two lasers and a large photographic film. One laser is shined on the subject and the other at the film, and it records the interference between the two lasers.
Of course, if you're nearsighted you'll need glasses to see it clearly. Or maybe contact lenses. If you have serious stabismus (crossed eyes) or are blind in one eye or for some other medical reason can't see stereoscopically, 3-D movies are no different than normal 2-D movies, but holograms are still in 3-D.
There are excellent holograms at the museum of magic and witchcraft in San Fransisco (if it's still there; I visited in the early 70s). There are also holograms at Disney World, most notably in the Haunted Mansion. There is a stereoscopic movie using polarized glasses at Epcot.
I saw a New Scientist article on the "universe may be a hologram" last week, but I think some theorists are misunderstanding what they're seeing (or reporters are misunderstanding what the theorists are saying).
Of course, our "reality" may not in fact be real. It may well be a videogame and you paid good money (or what passes for money in the real reality) to play (whoever dies with the most stuff loses), or it may be punishment for some horrible crime you commited in the real universe.
Or Morpheus may simply be looking for Neo. Or Geordi may be enjoying himself and you'll disappear when he says "end program".
Re:Flatland! (Score:2, Informative)
Yawn - this is a 25 year old theory (Score:2, Informative)
Re:Don't panic (Score:3, Informative)
it is interesting to note that the universe is mainly built out of second order laws. This means that in many cases there are a small number of poles or zeros that can control macroscopic behaviour and often analytic solutions exist. This would be how a designer would do it.
Nope. It is just that scientists use simple models like harmonic oscillator for most systems, simply because they are easy to solve. That doesn't mean that the universe is 'built' from second order laws. The rest of your post is also similar misinterpretations of QM, optics etc
Re:Plato (Score:4, Informative)
Re:Plato (Score:4, Informative)
How the hell does
Because I'm a thinking being engaged with the world around me, not a navel-gazing mystic.
get modded insightful 3??? It isn't insightful, it's an avoidance of the question being asked. Even if you read into the comment meaning that isn't there, but might reasonably be thought to have been intended, it still isn't insightful. Sheesh.
No, it doesn't. (Score:5, Informative)
No it doesn't. Science intentionally limits itself to that which can be observed and tested in a rational manner. Science does not and cannot say that the Universe is actually like that. Some philosophers say that, most scientists say that, and all athiests say that, but Science itself does not make that assumption.
Re:Okay... (Score:3, Informative)
It's more of a fundamental statement about the nature of horizons of any kind - whether that be the event horizon of a black hole, the horizon around an accelerating observer caused by the Unruh effect [wikipedia.org], or the horizon formed by the limit of the observable Universe. Any horizon implies that the information is constrained by the area of that horizon, and therefore whatever is inside the horizon must be specified by the exact same amount of information, which means things must be fuzzier than just plain quantum theory says.
Two overlapping horizons just makes one bigger horizon. And the holographic principle is talking about any arbitrary horizon at all - pick any volume of spacetime you want, the information inside is contrained by its boundary. There won't be any disagreement over what's going on on/within the boundary, its that the boundary determines how much information there is, not what's inside it.
Re:Plato (Score:3, Informative)
You can test the scientific method with the scientific method.
You sure can. But, it seems a little circular. If you trust the scientific method to tell you whether the scientific method is valid or not, you probably should trust it for physical sciences. I don't see how that really confirms anything.
Easy. Which process yields the most useful results? Rank them accordingly.
That's called pragmatism. Its a school of philosophy. See that? You just used philosophy to determine how you should go about doing science. See, its not so scary.