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.
Plato (Score:3, Insightful)
Was in Plato who suggested that people were only seeing a shadow of reality and it was up to philosophers to see the reality and describe it to the masses? It has been years since I studied philosophy, but I seem to recall something like this. I also seem to recall one of his lesser-known disciples, Aristotle discounting this altogether and starting his own school of thought.
Amazing how things come full circle.
Okay... (Score:5, Insightful)
Translating dense physics-speak is not my forte, but as I'm sure I'll be corrected if I'm wrong -- here goes. Einstein said that gravity is a linear (not discrete) force. What that means is that while it might decrease over distance, the effect never truly becomes zero. I think these guys are saying that it does, in fact, become zero. That is, gravity, contrary to Einstein's relativity equations... is discrete, like a particle, and not all like a wave (that can continue forever). Is that about right?
Re:Dumb question, I know... (Score:3, Insightful)
You could try starting by reading the article, which is mostly about experimental verification of previously untested theories.
Re:Plato (Score:5, Insightful)
> Amazing how things come full circle.
If by a 'full circle' you mean that you are able to identify one of the millions of ideas from the past that has, when interpreted in a certain way, certain superficial similarities with a theory in modern physics, then yes, amazing!
Re:Anti-science (Score:5, Insightful)
"Elements" are called elements because EARLY chemistry believed that all things were made up of a combination of elements in nature (earth, fire, water, etc). Of course over the years this was refined, and then refined again, and then once again refined some more. Atomic theory has come a LONG way from the expectation that all things were made out of the "elements of nature" through these constant refinements and NOT finding what we expected to find.
So... (Score:4, Insightful)
Re:Plato (Score:2, Insightful)
Re:So... (Score:3, Insightful)
Re:Plato (Score:3, Insightful)
Mixing philosophy and physics is actually a good idea.
Philosophy is actually a good study for the mind, it actually helps you to see other options.
If you can Philosophically ask yourself what if everything I know is wrong, then how might the universe behave to match my perceptions, without following what I expect to be true.
Sometimes Science comes up with an answer that fits that available data, which is actually incorrect. Which is normally found by finding new data that the original answer doesn't work. However it is possible there are a lot of things we conceive truth where we haven't found data to disprove yet. If the scientist was a good study in philosophy he may be able to come up with alternate solutions to his idea, which may lead to testing for new data for proof.
Re:Plato (Score:4, Insightful)
Why would they need to? There were "experiments" going on all the time in the ancient world, just as there are in refrigerators all over the planet today. A piece of food would get left somewhere, and when it was found again, it would be covered with mold, maggots and flies. It was obvious.
Re:Plato (Score:5, Insightful)
Re:Plato (Score:5, Insightful)
Re:Plato (Score:5, Insightful)
Philosophy starts with axioms. Science starts with observations.
No, science starts with the acceptance of the scientific method as a way to determine the "truth". It presupposes the accuracy of our senses, the non-arbitrariness of the universe, and even the notion that there is an external universe to study at all.
While many philosophic systems rest on axioms, those axioms are not arbitrary. They are invented, or discovered, because they logically explain the experiences of the philosopher. Philosophers use the scientific method to determine the axioms which underlie their systems. Without philosophy, there would be no way to argue that the scientific method was valid at all.
Re:Plato (Score:4, Insightful)
Physics is a subset of philosophy.
No, it's really not.
Yes, it really is. There's a reason that almost all nonmedical doctorate degrees carry the same title: Doctor of Philosophy. In its highest form, all human knowledge is similar--it requires human thought, and as such is inherently philosophy.
Re:Dumb question, I know... (Score:3, Insightful)
But generally speaking, how confident are we (read: Science) that we are actually describing the way the universe truly works, i.e., that we are not simply playing tremendously sophisticated math games?
It's not a dumb question at all, and it's one that scientists in all fields ask themselves often. IANAP, but my field, bioinformatics, is one that is also often accused of "playing math games" without producing testable hypotheses as well, so I'll take a stab at the answer:
We're as confident as we can be given the knowledge we have, no less and no more, but it will always take time to build up confidence in today's leading-edge research, and a lot of it will inevitably be discarded along the way. The only way to judge good science is, ultimately, how well it lasts. WRT physics, we know that Newtonian physics has stood the test of centuries -- we also know that it's wrong in some very important ways, but it's right enough to describe the everyday world we live in to a high level of precision. Einsteinian physics, a hundred years old at this point, is a better approximation, and it describes many extreme conditions in the universe (high speeds, large masses, and huge distances) quite well. Quantum physics, just a little younger, does a good job at the other extreme. These three paradigms put together (often with some effort) and applied to engineering problems form the basis of pretty much our entire technological world. They're all approximations, but if the approximations are good enough, that doesn't matter.
As for string theory, holographic universe, etc. -- who knows? As again in fifty or a hundred years.
Re:Plato (Score:5, Insightful)
And as for the comments below about the distinction between philosophy and physics, both Descartes and Newton were considered philosophers. Most contemporary philosophy, though, relies heavily on the natural sciences to support or confute philosophical theories. Philosophy of mind works with cognitive science, philosophy of language with various natural sciences, and metaphysics with chemistry, physics, mathematics, etc... I prefer Wittgenstein's definition of philosophy from the Tractatus. He calls philosophy an "activity" that is meant to sharpen and hone the critical thinking necessary in scientific inquiry. There are many cases where philosophical theories have been supported by scientific investigation just as many have been thrown out because certain scientific hypotheses do not support them.
Re:Plato (Score:3, Insightful)
Re:finite-resolution != hologram (Score:5, Insightful)
This, along with Dark Matter, Dark Energy and String theory are typical untestable theories which scientists lately have been using to fill in holes in their own understanding of the nature of the universe. Rather than going back to the drawing board when a model does not work, they use a cop out like this one to fill in the blanks.
Actually, this theory was a predicted consequence of a combination of information theory, relativity and quantum theory before there was any evidence for it. This is not a "model didn't work, so let's invent something to account for it" scenario: this is a "model predicted something and it looks like we might have found it" scenario.
Re:Plato (Score:3, Insightful)
Science starts with the proposition that the Universe is rational and can be observed in a rational and repeatable manner.
This is not so much a "proposition" as it is the baseline, default, common-sense observation based on our own experiences. I pick up the rock, I drop it, the rock falls to the ground. I pick it up and drop it again, and again it falls to the ground. Etc. We learn this from infancy, long before either "science" or "philosophy" enter our heads. Everything else -- all the layers of mysticism which philosophers and theologians have over the millennia attached to our perceptions of reality, and all the hypotheses which scientists have floated over the last few centuries -- falls into the category of "propositions in need of testing, otherwise worthless." But the fundamental difference between science and philosophy is that scientists' propositions can be and are tested, and discarded if found wanting, while philosophers' remain no matter how little use they may be in describing the real world.
Re:Plato (Score:5, Insightful)
Physics is a subset of philosophy.
No, it's really not.
I hate to be so blunt, but you don't know what you are talking about. Until very recently, science was called natural philosophy. All the sciences have their origins in philosophy, and anyone who ignores this does so at their own peril (and shows their ignorance of both science and philosophy).
I say peril because it is easy to take empirical science for granted. Empiricism is an epistemological position that must be defended, and to ignore the fact that science is a branch of philosophy is to forget how fundamental epistemological assumptions are to science.
Knowledge in science doesn't just happen. You don't observe theories or laws, and even observation itself is tricky. To say that science is about observation is to be way too glib about science. Science is much, much more complicated than that, and deserves much more respect and reflection than you give it.
You see, most philosophers understand that. Many scientists don't. Even fewer nonscientists understand it.
I don't say any of this to belittle science; I am a scientist. I say it because science is much more complicated than "observation," and seeing it as a proper branch of philosophy recognizes that.
Re:Plato (Score:3, Insightful)
No, science starts with the acceptance of the scientific method as a way to determine the "truth".
When you say "the scientific method," you're sweeping under the rug a whole collection of methods, all of which have been tested and modified for centuries, many of which have been discarded along the way when something better comes along, and which vary greatly from field to field. IOW, there is no "scientific method" -- there is a collection of methods generally agreed upon by scientists as the result of long experience.
It presupposes the accuracy of our senses, the non-arbitrariness of the universe, and even the notion that there is an external universe to study at all.
As I replied to another poster in the thread [slashdot.org], this is the default assumption based on our experiences from infancy, and there is no reason to assume otherwise. Mystics love trying to poke holes in our perceptions of reality, but they do so without offering any evidence for their claims.
While many philosophic systems rest on axioms, those axioms are not arbitrary. They are invented, or discovered, because they logically explain the experiences of the philosopher.
Ah, but (good) scientific hypotheses logically explain the experiences of everybody, that's the difference. Philosophers' axioms may make sense to them and to people who think like them, but they fail in general applicability.
Philosophers use the scientific method to determine the axioms which underlie their systems.
Please, tell us about the methods of the science done by Aristotle, or Augustine, or Wittgenstein!
Without philosophy, there would be no way to argue that the scientific method was valid at all.
Only if you define "philosophy" so broadly that the word loses any meaning. In the real world, the best argument for science is that it works; it produces useful results. Philosophy has never cured a disease, or built a computer, or shown us anything in the universe beyond what we can see with the naked eye. Science has done all of these things and more, and will continue to do so.
Re:Don't panic (Score:3, Insightful)
For instance, it's not like a particle might have some particular momentum and velocity, but somehow the universe is just being lazy about deciding their values. Rather, the notion of having a definite momentum and definite position is contradictory.
QM is much weirder than you think.
Re:Plato (Score:3, Insightful)
Doctoral degrees carry the title "PhD" as a result of a historical artifact. That's all. "Bachelor" and "Master" are equally artifactual.
If you define all human thought as philosophy, then the word is so broad as to be meaningless. What do you call that field which is practiced by the people we generally call "philosophers?"
Re:Plato (Score:3, Insightful)
That basic assumption of science, as I've explained elsewhere in this thread, is our default view of the world, based on our experiences from the moment we're born. Any other assumption, such as the non-observability or non-causality, is an extraordinary claim which needs to be backed up by some pretty solid evidence -- something which philosophers and other mystics are notoriously unwilling to provide.
Re:Plato (Score:4, Insightful)
While I won't argue with you that science was largely invented by philosophers (and of course I agree entirely that it has rendered large swathes of previously philosophy obsolete) I disagree entirely that this historical curiosity makes it a subset of philosophy. Like many intellectual fields, it's grown far beyond its roots. By way of analogy, modern science is no more a subset of philosophy than modern literature is a subset of epic poetry.
Re:Dumb question, I know... (Score:2, Insightful)
It's sort of the Epicycles problem again. When they assumed the Earth was the center of the universe, they modeled the solar system using circles "orbiting" circles. They kept adding complexity to the epicycle model with offset bars and more layers of circles. It indeed could be made to make accurate predictions about the movement of sky objects. However, it didn't mirror the actual model (Sun at center). Nobody really knew this until the simpler sun-center model was introduced, and everyone found it was a simpler explanation.
Thus, fitting observations and mirroring the actual underlying mechanism may not be the same thing. Mathematical regression is also an example of this: the regression formulas can be made to model almost any continuous curve if you throw enough terms into them. However, that does not mean that the resulting equation in any way matches the mechanism that generated the actual curve. (Epicycle circles-and-bars are a kind of "circular regression" in a rough sense.)
It's difficult to know if a theory such as String Theory is suffering the same problem. Its complexity does suggest this. But, until a simpler model comes along, it's the current king.
Re:Plato (Score:3, Insightful)
Bose-Einstein condensates? Superfluids? Amorphous solids? There's at least a dozen states of matter.
Re:Plato (Score:3, Insightful)
When you say "the scientific method," you're sweeping under the rug a whole collection of methods, all of which have been tested and modified for centuries, many of which have been discarded along the way when something better comes along, and which vary greatly from field to field.
How can the scientific method be tested and modified without some external framework in which to value them? How can you evaluate which method is "better" without some way to rank them? To do this, you need a philosophical underpinning to make that value judgment.
As I replied to another poster in the thread, this is the default assumption based on our experiences from infancy, and there is no reason to assume otherwise.
Just because it is the default assumption, doesn't mean its correct. Should we be limited in all our endeavors, to the basic and oversimplified infantile way of thinking? Are you saying its not even worth thinking about?
Philosophers' axioms may make sense to them and to people who think like them, but they fail in general applicability.
I don't know what it is you think philosophers do, but just randomly creating axioms is not it. Philosophers are constantly comparing the results of their theories against their perceptions, and modifying them if need be. You are grossly oversimplifying the practice of philosophy.
There have always been a subset of philosophers who spend their entire lives counting the angels on the heads of pins; but there is real, important work being done on many issues. The philosophy of science is just one example. You have no way to judge whether your "scientific method" is worth pursuing without philosophy; even a philosophy as basic as your common-sense approach.
Re:Plato (Score:3, Insightful)
Until very recently, science was called natural philosophy.
And now it's not.
All the sciences have their origins in philosophy, and anyone who ignores this does so at their own peril (and shows their ignorance of both science and philosophy).
The historical roots really aren't the point; as I pointed out to another poster in the thread, many intellectual fields have outgrown their roots, and modern science is no more a subset of philosophy than modern literature is a subset of epic poetry.
I'd be rather careful about saying "all the sciences," BTW. Astrology led rather directly to astronomy, and alchemy to chemistry -- and while both of these brands of mysticism certainly had philosophical elements, neither was really "philosophy" in the modern understanding of the word.
Empiricism is an epistemological position that must be defended
The only defense that need be made of empiricism is that it works. Attempts by mystics to undermine this are ceaseless, but doomed. I'm not going to bother retyping my own words; please take a look at some of my posts higher up the thread.
To say that science is about observation is to be way too glib about science. Science is much, much more complicated than that, and deserves much more respect and reflection than you give it.
I never claimed that science is only about observation, any more than I claimed that philosophy is only about axioms; I merely pointed out that these are the places where the respective fields start. And after that, as I acknowledged, the thought processes of scientists and philosophers are often quite similar. But the starting point makes an enormous difference in the outcome.
Believe me, I give science a lot of "respect and reflection" every day. In fact, I probably ought to stop noodling around on /. and get back to work ...
Re:Plato (Score:5, Insightful)
Saying "We basically experience the world as it really exists" amounts to one pretty serious assumption, whether or not you want to call it that.
Re:Plato (Score:5, Insightful)
In science, our assumptions are based on experimentation.
Not true. Several assumptions have to be made before experimentation is possible. The scientifc method itself is an assumption.
Re:Plato (Score:5, Insightful)
Until very recently, science was called natural philosophy.
And now it's not.
You missed the point. I wasn't making the claim that just because it was called "natural philosophy" that means science is philosophy. My point was that you should think about the REASONS why it was called natural philosophy. Who cares what we call it now?
Observation is not the core of any science. Although observation is important, it is not a sufficient condition for science. To understand science, you have to understand how theories are built and defended. We don't OBSERVE the laws of motion. We don't observe natural selection. We don't observe relativity. These are theories to explain observations. How we go from observation to real, meaty scientific knowledge is where the real interesting part is, and that requires philosophy. You can't just take it for granted because it "works" (after all, that would be circular, wouldn't it?)
Re:Anti-science (Score:3, Insightful)
"Elements" are called elements because EARLY chemistry believed that all things were made up of a combination of elements in nature (earth, fire, water, etc).
Their four elements were earth, wind, fire, and water. I believe we simply misunderstand the ancients. The four "elements" weren't elements as we know them (hydrogen, helium, etc) but the four states of matter: solid, gaseous, plasma, and liquid.
Of course, they misunderstood the universe. But of course we do, too, although we misunderstand it less and less as time goes on.
Re:Plato (Score:5, Insightful)
It probably doesn't matter in this forum which definition you use; what matters most on the internet is that the other guy is wrong. (And if you think I'm talking about you, I'm not. It's the other guy who's actually wrong. We are right-on here. Yes sir! Go us. we rock.
Re:Plato (Score:2, Insightful)
Scientific thinking natural in humans. We learn about reality through our interaction with it and we empirically create models consistent with reality. These models are the basis for our exceptional ability to adapt. We use them to predict, plan, and build -- and when they don't work we change them. Eventually they work very well. Pragmatically speaking, our models come into alignment with reality. Philosophy, mathematics, and any other attempts at rational thought all develop from the same basic practical needs to survive in and adapt to a complex and changing environment. Some types of philosophical thinking may not have direct, practical, testable applications but they may help us create higher-level models in which to integrate our counter-productive, vestigial fears.
Re:Don't panic (Score:3, Insightful)
explain please how an entity can design itself. Just because what you typed reads like valid english, doesn't make it a profound truth. In your case, you're just blabbering nonsense.
Re:Plato (Score:3, Insightful)
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.
I suppose maybe because it's an acknowledgment, however unsubtly expressed, that there's a degree of impracticality inherent in the notion of questioning fundamental principles of our existence and universe that doesn't really help the advancement of hard science. For instance, questions such as whether or not the universe actually exists, or whether I'm the only real being in the universe and all of you are illusions or very clever algorithms don't have much practical application when you get right down to it. Science has, arguably, improved our lives in very real and very practical ways. It's a bit harder to make that case for philosophy.
As such, I tend to view the relationship between modern science and philosophy as rather flimsy at best. Or, put another way, I suppose you could say is that science is about finding answers to interesting questions, where philosophy seems mostly delight in coming up with interesting questions and scenarios to which no one can come up with a reasonable answer.
Re:Plato (Score:2, Insightful)
When looking at the subset of philosophy called philosophy of science, it becomes more apparently that science really is still just a subset of philosophy. Philosophy is not just people making random guesses about how they feel the world is, but rather it is about using evidence to try to prove one's point. Science is about gathering the data, and then using that data to draw conclusions is philosophy. Science cannot exist without philosophy.
Re:Plato (Score:3, Insightful)
No, science starts with the acceptance of the scientific method as a way to determine the "truth". It presupposes the accuracy of our senses, the non-arbitrariness of the universe, and even the notion that there is an external universe to study at all.
No it doesn't. The accuracy of our senses is a conclusion we reach after many repeated observations that yield the same result. In fact, science has shown that in many cases our senses aren't accurate.
Further, science would work just as well if the universe were arbitrary. Suppose the entire universe were a simulation in a computer. After all, there's no way to prove it's not. If our universe is a simulation, then it is arbitrary. Whoever wrote it can go in and change any constants or even laws of physics that they want. But wait, science still works. We can still make observations, make predictions based on those observations, make models based on the results of those predictions, and make technology based on those models.
Of course the science we do in a simulated universe won't have anything to do with that actual universe, but it doesn't have to. Science is not about the "truth". It's just a process, and that process can take place without assuming any sort of external reality at all. Even a nihilist can be a scientist.
Re:Don't panic (Score:3, Insightful)
So it's not necessarily that reality is fuzzy and indistinct, more that our knowledge of it is limited.
This is a popular and comforting notion that has long been dis-proved by empirical evidence: the double slit experiment is the classic example that shows that a particle is fuzzy, it's not just our knowledge of it. Heck, this even the point of the cat in a box. Schroedinger didn't say that the cat's state was indeterminable, he said it was in an indeterminate state.