Reality is an illusion, lunchtime doubly so

October 20, 2010 11:33 AM

Fermilab particle astrophysicist Craig Hogan is building a holometer to directly measure if our reality is an illusion - that is, nothing more than a hologram.

From the article: "Black hole physics, in which space and time become compressed, provides a basis for math showing that the third dimension may not exist at all. In this two-dimensional cartoon of a universe, what we perceive as a third dimension would actually be a projection of time intertwined with depth. If this is true, the illusion can only be maintained until equipment becomes sensitive enough to find its limits."

No word if we are just a help-me message stuck in a barrel-shaped robot existing on a higher plane or not.

posted by Old'n'Busted (59 comments total)

Philip K. Dick would have enjoyed this story, had he been real.
posted by Joe Beese at 11:35 AM on October 20, 2010 [16 favorites]

I have enough trouble believing in reality without someone disproving it to me.
posted by toodleydoodley at 11:36 AM on October 20, 2010 [2 favorites]

And the universe would have got away with it if it wasn't for those pesky scientists...
posted by doublehappy at 11:39 AM on October 20, 2010 [4 favorites]

Now he is building the most precise clock of all time

Pratchett predicted and warned us about this in The Thief of Time. There are probably auditors about somewhere disguised to look just like us.

*winds up portable procrastinator*
posted by quin at 11:51 AM on October 20, 2010 [1 favorite]

It wasn't an illusion until the act of observing it as such made it one. Thanks a lot, jerk.
posted by Zed at 11:52 AM on October 20, 2010 [4 favorites]

Someone doesn't understand the holographic theory of the universe at all.
posted by empath at 11:53 AM on October 20, 2010 [1 favorite]

Physics n00b question: Isn't the universe effectively pixelated at Plank length anyway?
posted by Aizkolari at 11:55 AM on October 20, 2010 [1 favorite]

Someone doesn't understand the holographic theory of the universe at all.

Me? Is it me?
posted by nzero at 11:56 AM on October 20, 2010 [6 favorites]

The phrase "reality is an illusion" is a bit misleading here.

What the experimenters hope to test is whether the holographic principle is true.

The holographic principle is the idea that any spherical region of space can contain no more information than could be encoded on its surface area.

If a particular spherical volume of space could only take on 1000 different states, doubling the radius of the sphere would only increase it to 4000 different states, not 8,000 as the increase in volume would suggest.

In essence, you only need two dimensions to model our universe, not the three we perceive.

(Perhaps someone more expert in this field will correct any misinformation I present)
posted by justkevin at 11:58 AM on October 20, 2010 [7 favorites]

Oh great, a scientist peering beyond the very walls of reality itself. There's no way this can go badly.
posted by The otter lady at 11:58 AM on October 20, 2010 [6 favorites]

Maya, concept first conceived two or three millenia ago

Interesting that they're trying to prove it (or not) ...
posted by The Lady is a designer at 11:59 AM on October 20, 2010

Hi, horrible science writing!

No one thinks that "reality is an illusion". The underlying idea here, as phrased in Hogan's paper, is that: "A holographic quantum geometry of spacetime has two spatial dimensions instead of three, and the apparent third dimension emerges, by a hologram-like encoding, along a null projection of a 2D sheet." It's a mathematical description of quantum gravity, which is a largely unsolved area of physics.

The claimed innovation here is that if such geometric descriptions of spacetime on the quantum level are valid, there would be measurable fluctuations in the position of events. That's what they're trying to measure at Fermilab, apparently.
posted by mr_roboto at 12:01 PM on October 20, 2010 [4 favorites]

My brain hurts.
posted by PenDevil at 12:01 PM on October 20, 2010 [1 favorite]

Physics n00b question: Isn't the universe effectively pixelated at Plank length anyway?

Yeah. If you look at the paper, you can see how the entire idea is built up from the concept of the Planck scale. The innovation here is a method to observe it, which is based on the holographic principle.
posted by mr_roboto at 12:04 PM on October 20, 2010

Maya, concept first conceived two or three millenia ago

Interesting that they're trying to prove it (or not) ...

They're really not.

Thanks, horrible science writing!
posted by mr_roboto at 12:05 PM on October 20, 2010 [2 favorites]

Yes, the universe is effectively pixelated (or digitized) at the plank length anyway - but that would be true whether the universe is a holographic projection of a two dimensional surface, or is an Einsteinian four dimensional space-time universe as we presently think.

In any event, there are lots of illusions in our universe. We perceive solid matter as being a continuous material, when closer examination shows that it is mostly empty space, the apparent solidity of which is the result of force fields emanating from sub-atomic particles. And although the sun appears to rise and set, we know that actually it is the Earth which rotates, although we do not feel its rotation. And so forth. If the universe turns out to be holographic, that is just one more illusion (although a very dramatic one) on the list. In other words, reality is not an illision, no matter how many illusions it contains. Reality remains real. Strange, but real.
posted by grizzled at 12:05 PM on October 20, 2010 [2 favorites]

If this is such a great and important experiment, why is the "lab" set up in a hallway?
posted by rocket88 at 12:06 PM on October 20, 2010

Somewhere, in the dark, in a locked box, in the corner of a long forgotten laboratory, a cat shrugs and mutters to himself "Figures."
posted by Jofus at 12:06 PM on October 20, 2010 [1 favorite]

The average "plank length" is usually on the order of a few meters.
posted by Wolfdog at 12:08 PM on October 20, 2010 [4 favorites]

That is, Planck. Excuse the typo.
posted by grizzled at 12:08 PM on October 20, 2010

Somewhere else, in the dark, in a locked box, in the corner of a long forgotten laboratory, a cat shrugs and does not mutter to himself "Figures."
posted by lalochezia at 12:08 PM on October 20, 2010 [8 favorites]

A tree falls...
posted by The Lady is a designer at 12:11 PM on October 20, 2010

The infinite singularity goes quack.
posted by Theta States at 12:13 PM on October 20, 2010

justkevin, grizzled: but at what criteria are you using to say "this is an illusion, and this is reality", when you cannot tell which is which? 3d space is an illusion - or a projection, if you well - of 2d space, caused by... something. We accept it as reality - but why? Because we operate within it so nicely?
Now, what I am very interested in is if (when!) they figure out what causes this, and are able to shift the "frequency" of... something... that causes 2nd space to present a 3d reality, and if so, are were able to cross over into it? (and yes, that is the same as people saying the 4d space is a projection of 3d and so on and so forth).
posted by Old'n'Busted at 12:13 PM on October 20, 2010

but at what criteria are you using to say "this is an illusion, and this is reality", when you cannot tell which is which?

Look, this is really a subject more for metaphysical philosophy than for science itself. Science has models, and it has observations, and its goal is to match the models to the observations, preferably in a predictive fashion. Anything beyond that--including comments on the "nature of reality"--is metaphysics, not physics.

Frankly, I don't think there's much that quantum gravity can tell us about the "nature of reality" beyond the observations that models of quantum gravity predict (and those predicted observations are few and far between). As for the observations themselves: yeah, those are reality, I guess. So long as they're reproducible.
posted by mr_roboto at 12:29 PM on October 20, 2010 [2 favorites]

but at what criteria are you using to say "this is an illusion, and this is reality", when you cannot tell which is which?

It's pretty easy when you use PKD's law: "Reality is that which, when you stop believing in it, does not go away"
posted by lumpenprole at 12:30 PM on October 20, 2010 [2 favorites]

Now, what I am very interested in is if (when!) they figure out what causes this, and are able to shift the "frequency" of... something... that causes 2nd space to present a 3d reality, and if so, are were able to cross over into it? (and yes, that is the same as people saying the 4d space is a projection of 3d and so on and so forth).

You need six to make the four cornered cube.
posted by cmoj at 12:34 PM on October 20, 2010

The average "plank length" is usually on the order of a few meters.

That is, Planck. Excuse the typo.

No, no, you were right the first time. I have several planks approximately a few meters long in my driveway right now, in fact.

Now, what's this FPP on about?
posted by davejay at 12:34 PM on October 20, 2010

Okay. But why?
posted by carsonb at 12:38 PM on October 20, 2010

Awesome!

Probably!
posted by Uther Bentrazor at 12:39 PM on October 20, 2010

The mention of the sun's path through the sky is an apt comparison. Just because the motion of the sun is an illusion created by the rotation of the earth, that does not make the sun less real, or its path through the sky less real.
posted by Nothing at 12:50 PM on October 20, 2010 [2 favorites]

Interesting stuff.

I know a guy who works on LIGO. His description of the initial science runs was simple. "We knew the world was an incredibly noisy place. We had no idea how noisy the world was." The big surprise, to them, was how badly EM noise affected them. They knew that mechanical vibration was going to be a nightmare, but the EM noise was, in many ways, worse.

LIGO was built in quiet areas -- the Hanford Reservation in Washington and near Livingston, LA.

Now, Fermilab. Fermilab is built in suburban Chicago. Well, it wasn't when it was built, but it sure is now. IL-5 was just another two lane state route when they built the lab, now, it's I-88. There are a lot of people at Fermilab, and they have cars.

Heck, Fermilab has a herd of bison. They're very good at vibration. But that's not the worst part.

The worst part will be the EM noise, because Fermilab has lots of sources, because Fermilab is chock full of large particle accelerators, including the 2nd most powerful and largest in the world, the Tevatron.

So: There's a great deal of noise at Fermilab, and you really can't get rid of it for a long while -- while the Tev may be shut down soonish, the MI will still be running as part of the various neutrino experiments. You're not getting rid of the cars. You could get rid of the bison, but.

I'm really interested on how they're going to handle the noise isolation.
posted by eriko at 12:55 PM on October 20, 2010 [1 favorite]

One guy who's written insightfully on the whole illusion/reality thing is actually Richard Dawkins. He makes the point that we evolved to perceive "reality" the way it is most convenient for us to perceive it. Thus we can see a hole in a wall to walk through it, but can't see the comparatively vast empty space between atom nuclei in "solid" matter. Somewhat relatedly bats "see" using sonar because that's what works for bats; the analogy is our eyesight, not you going into a cave and banging on a frying pan to listen for echoes. It's hard to conceptualize because we're not wired that way.

So everything's kind of an "illusion" in the sense that we perceive the world around us in a way that's extremely specific to us. What it "really" looks like might not be an answerable or even coherent question.
posted by eugenen at 1:06 PM on October 20, 2010 [1 favorite]

I like to share this video of Professor Raphael Bousso explaining the Holgraphic Gravity theory. It's pretty neat and not too hard to understand and helps demystify away from the new-agey bullshit.
posted by symbioid at 1:15 PM on October 20, 2010 [3 favorites]

eriko: "Interesting stuff.

I know a guy who works on LIGO. His description of the initial science runs was simple. "We knew the world was an incredibly noisy place. We had no idea how noisy the world was." The big surprise, to them, was how badly EM noise affected them. They knew that mechanical vibration was going to be a nightmare, but the EM noise was, in many ways, worse."

I just had a great idea for a federal grant. An outer-space particle accelerator. Away from the earth stuff. Granted then you have to deal with cosmic rays and other such things. Also... Republicans and their ilk blocking funds.
posted by symbioid at 1:23 PM on October 20, 2010

It should be noted that when you get sucked in to the next dimension, make sure you don't step ANYWHERE near the slimes. And when the giant black cat thing appears, run back and jump on the vine.

But chances are, the alternate dimension will just frustratingly kill you.
posted by Theta States at 1:23 PM on October 20, 2010

The good news: he'll discover that our reality is not a hologram.
The bad news: he'll discover ether.
posted by sebastienbailard at 1:46 PM on October 20, 2010 [2 favorites]

"My, that was easy", says man, and goes on to prove that black is white, and gets killed on the next zebra crossing.
posted by kcds at 1:56 PM on October 20, 2010

"So everything's kind of an "illusion" in the sense that we perceive the world around us in a way that's extremely specific to us. What it "really" looks like might not be an answerable or even coherent question."

In other words, Dawkins is good at paraphrasing Kant.
posted by oddman at 2:20 PM on October 20, 2010 [1 favorite]

(Not that Kant was the first person to make this sort of observation.)
posted by oddman at 2:22 PM on October 20, 2010

Wouldn't it just be easier to spin a top and see if it falls down?
posted by spock at 2:24 PM on October 20, 2010

Reality is for people who lack imagination.
posted by spock at 2:24 PM on October 20, 2010

Oddman - (Not that Kant was the first person to make this sort of observation.)
You're probably thinking of Plato's Cave.
posted by Old'n'Busted at 2:25 PM on October 20, 2010

The map is not the territory.

Saying that the universe can be described as something doesn't mean that the universe is only that. There are many ways to model the universe.

Even if the universe can be described as a 3d projection of a 2 dimensional surface, that doesn't mean the universe is 'really' a 2 dimensional surface.

Science creates models, and the models are either accurate or not. But the models are not reality.
posted by empath at 2:30 PM on October 20, 2010

Those comments are gold.
posted by Blazecock Pileon at 3:04 PM on October 20, 2010

Well Plato is a clear precursor, but I was actually thinking of the Pre-Socratics like Heraclitus and Parmenides, Early Moderns like Berkeley and Locke and many others who thought that the perceived world was illusory (or at least misleading in various ways).
posted by oddman at 3:32 PM on October 20, 2010 [1 favorite]

In other words, Dawkins is good at paraphrasing Kant.

(Not that Kant was the first person to make this sort of observation.)

Sure, but he grounds the concept in examples from biology in a way that I thought was useful and particularly pertinent here.
posted by eugenen at 3:33 PM on October 20, 2010 [2 favorites]

I'm really interested on how they're going to handle the noise isolation.

The claim is that the frequencies they're interested in a relatively "quiet".
posted by mr_roboto at 3:50 PM on October 20, 2010

eugenen, it's interesting that you mention that because Locke makes exactly that general claim, i.e. that we have the senses which are best suited to helping us do well in the world.
posted by oddman at 4:03 PM on October 20, 2010

I know that there are 3 dimensions because I can see it at the movies now.
posted by randomkeystrike at 4:33 PM on October 20, 2010 [1 favorite]

BTW, +1 to the OP for the thread title. Words to live by, I always say.
posted by randomkeystrike at 4:34 PM on October 20, 2010

A holographic quantum geometry of spacetime has two spatial dimensions instead of three, and the apparent third dimension emerges, by a hologram-like encoding, along a null projection of a 2D sheet.

That's what she said!
posted by Sebmojo at 5:21 PM on October 20, 2010

OK. Who has the last word on the illusion/reality question: the physicists, the linguists, the semioticians, the dead William Burroughs, or Fellini's hermaphrodites? (NOne of the above?)
posted by kozad at 5:28 PM on October 20, 2010

Well Plato is a clear precursor, but I was actually thinking of the Pre-Socratics like Heraclitus and Parmenides, Early Moderns like Berkeley and Locke and many others who thought that the perceived world was illusory (or at least misleading in various ways).

Ah, so basically, reality is an agreed-upon hallucination? Or, as my brother says, reality is for people who can't handle drugs?
posted by Old'n'Busted at 6:40 PM on October 20, 2010

This isn't the first time I've enjoyed the comments more than the post, but it's definitely top ten.
posted by empatterson at 8:29 PM on October 20, 2010 [1 favorite]

I was talking about Planck length digitization with some audiophiles who didn't believe me... Dumbos.
posted by MNDZ at 10:17 PM on October 20, 2010

What if it turns out the universe is a 3D projection of a 1D surface?
posted by eye of newt at 12:08 AM on October 21, 2010

A holographic quantum geometry of spacetime has two spatial dimensions instead of three, and the apparent third dimension emerges, by a hologram-like encoding, along a null projection of a 2D sheet.

This is further supporting evidence to my theory that Phycists, years ago, discovered that the universe actually runs on magic and ever since that day have spent their time gently mocking the rest of us.
posted by metaBugs at 6:34 AM on October 21, 2010

In reply to the question, What if it turns out the universe is a 3D projection of a 1D surface?
posted by eye of newt, let me mention pedantically that a surface is by definition two dimensional; if the universe were being projected into 3D from a single dimension, that single dimension would be described as a line, not a surface. We have no reason, either theoretical or observational, to hypothesize that the universe is being holographically projected into 3D from a line, rather than from a surface, but even if that were to unexpectedly turn out to be the case, it would not alter our experience of living in a three dimensional universe, it would just mean that the origin of that experience is even stranger than we had imagined. And what if the universe comes from a zero dimensional point? In a sense it may, since the Big Bang theory (the cosmological Big Bang theory, not the TV series) suggests that the universe originated as a singularity which exploded. But even if the universe had a zero dimensional origin, that is strictly in the past.

On the question of exactly how we distinguish between reality and illusion, and whether reality is just an agreed-upon hallucination, there are lots of good comments on this subject already. Reality tends to be a practical concern. When a car is bearing down upon you, but you don't agree that the car is real so you don't get out of the way, you get killed anyway. Reality doesn't care if you agree with it (as Philip K. Dick pointed out). If you were just hallucinating that a car is bearing down upon you, and you decide not to get out of the way (either because you want to die, or because you are aware that you are hallucinating) then the hallucinatory car doesn't kill you. So there is a difference.
posted by grizzled at 7:00 AM on October 21, 2010