Category: universe

What You See Ain’t What You Get

Donald Hoffman’s book The Case Against Reality is nicely summed up by the subtitle: Why evolution hid the truth from our eyes.

That is, he argues that the world that we see (and the one we hear, smell, touch and taste) everyday is a kind of illusion. And not just a minor illusion but a major, systemic one. The kind of illusion you get in The Matrix, except far, far stranger.

In the movie The Matrix, after all, the Machines have built a virtual reality in which to house humanity’s minds while their bodies are used as batteries (yeah, what always sounds lame to me, too). But the virtual reality is basically identical to the reality of humanity’s past.

The world that we experience is much weirder, according to Hoffman, a cognitive psychologist, because it is not a simulation of reality but, rather, a façade that bears little if any resemblance to the underlying reality of our universe.

Fitness Stomps Truth into Extinction

Here’s Hoffman’s argument in a nutshell: we have all been shaped by evolution to reproduce rather than see the truth of things.

That is, we were designed by nature to only sense what we need to sense in order to survive long enough to produce offspring. If nature needs to lie to us to get the job done, that’s just fine by nature.

“Our minds evolved by natural selection to solve problems that were life-and-death matters to our ancestors, not to commune with correctness,” sums up the cognitive scientist Stephen Pinker.

Hoffman takes that basic observation further by producing the Fitness-Beats-Truth Theorem, or FBT. Consider the following fable to understand his theorem better.

Frankie and Terry Wash Up on Evolution Island

Once upon a time, where were a couple of geckos happily sunning themselves on a log on the tropical beach. Suddenly, a huge rogue wave enveloped the beach and floated the poor geckos out to sea. Things looked grim for our heroes, whom we’ll call Fit Frankie and Truthful Terry.

But then the log floated up on what seemed to be an island, an exceedingly weird island where nothing was familiar. In fact, the whole place looked gray and black. I don’t mean that the trees, bugs, bushes and rocks were gray and black. I mean that there were no recognizable land formations at all. Just gray blobs and white blobs.

This freaked out both of our gecko sojourners but, hey, they were alive even if they had slipped into some bizarre gray-and-black pocket universe that we’ll call Evolution Island.

The Elixer of Life

Aside from the colors, though, there was another strange thing about the island: it turns out there was something essential to life hidden amid the gray and black regions. Think of this essence as the “elixir of life.” If the geckos got enough of it, they could live on. If they didn’t get enough–or in fact got too much–they could die. (Note: this is kind of like oxygen is to us: not enough, we suffocate; too much, we get oxygen poisoning and kick the bucket.)

Sounds stressful, right? How were they supposed to know where the elixir was? And how could they know when they were getting too much or not enough of it?

Although they were both in a tough situation, it turns out that one of our gecko heroes had what sounds like an advantage. Truthful Terry saw things as they really were: that is, Terry saw gray when there was less elixir and black where there was more. Lucky Terry.

Fit Frankie, however, didn’t see Evolution Island as it really was. Instead, Frankie’s eyes somehow saw the black and gray shades differently. Frankie literally “saw” fitness (which Hoffman refers to as “fitness points”).

Here’s how it worked: in the places where Frankie could get just the right amount of elixir (that is, not too much, not too little), Frankie saw black. In the other places, Frankie saw gray.

Just to be clear here, what Frankie saw was an illusion. Terry saw the true world, while Frankie saw a kind of fiction.

But here’s the thing: it was a very useful fiction.

Frankie’s Descendants Take Over Evolution Island

In short order, Fit Frankie realized she was felt a lot better hanging out in the black zones and so consistently gravitated toward those parts of Evolution Island. Truthful Terry, on the other hand, saw the true colors of the island but had a harder time thriving, constantly trying to find the right balance between the gray and black zones so as to get just the right amounts of elixir. Terry saw truth while Frankie saw “fitness points.”

Over time, Fit Frankie thrived and had many children (being one of those parthenogenetic species of geckos). Truthful Terry, however, figured out how to survive but just barely, being sometimes sick from too much or too little elixir. Although she could see the world as it really was, she had few offspring, and the few that she had just couldn’t compete with the many offspring of Fit Frankie.

So, it turned out that seeing only the truth was actually a curse for Terry, whereas seeing a useful lie was a blessing for Frankie. Frankie’s “fitness vision” beat out Terry’s “truth vision,” and today Frankie’s offspring thrive on Evolution Island whereas Terry’s offspring went extinct many generations ago.

on Winning the Evolutionary Game

This fable, as you might have guessed, was inspired by an evolutionary game created by Hoffman and his colleagues. Game theory, of course, is a branch of applied mathematics that provides tools for analyzing situations in which players make decisions that are interdependent. The goal of game theory is to better understand the outcomes of different interactions among the “players.” (Frankie and Terry were the players in the example above.)

Evolutionary game theory is one application of game theory that is used to model evolving populations in biology. Wikipedia reports, “It defines a framework of contests, strategies, and analytics into which Darwinian competition can be modelled. It originated in 1973 with John Maynard Smith and George R. Price’s formalization of contests, analyzed as strategies, and the mathematical criteria that can be used to predict the results of competing strategies.”

Hoffman and his colleagues created multiple evolutionary games in order to test their Fitness-Beats-Truth Theorem. They also created a separate but complementary mathematical model. Both initiatives produced the same result: life favors fitness over truth. That is, creatures that view the world in terms of “fitness points” inevitably trounce creatures that see the world as it truly is. Useful lies beat plain truth every time.

The moral of the story?

The world we see around us is not based on a true representation of reality but is, rather, a useful lie that allowed our ancestors to stay alive long enough to reproduce. In short, you and I, dear readers, are the offspring who have inherited our own version of Evolution Island. Viva la illusion!

Nature Is a Big Fat Liar, Just Like Your Smartphone

Your computers lie to you. Intentionally. For good reason.

Let’s say you want to write a document on a computer. You almost certainly start with some sort of computer icon. In my laptop, I have that Microsoft Word icon with that big blue W in it. I click that to open the application. On my smartphone, I tend to use Google docs instead, clicking on little white circle with a blue rectangle on it.

In either case, I “click on” the icon and it opens up a bigger rectangular document into which I can type words.

It’s useful, right? Absolutely. But it’s also a kind of fictional overlay. Hoffman explains:

The blue icon does not deliberately misrepresent the true nature of the file. Representing that nature is not its aim. Its job, instead, is to hide that nature–to spare you tiresome details on transistors, voltages, magnetic fields, logic gates, binary codes, and gigabytes of software. If you had to inspect that complexity, and forge your email out of bits and bytes, you might opt instead for snail mail.

Evolution does the same thing for us, posits Hoffman. It provides us with a kind overlay that helps us survive and reproduce. He calls it the interface theory of perception, or ITP.

Interface Theory of Perception

For example, only in recent history have humans discovered the whole spectrum electromagnetic radiation, aka light. It turns out we can see only a tiny portion of the spectrum–about 0.0035%–the range we now call visible light. We evolved to be able to see only the range that best helped us survive, and even then we didn’t see electromagnetic radiation itself.

Instead, we see colors, which probably don’t even exist outside of our human perceptions. Colors are part of nature’s hack for helping us survive. We can see when fruit is ripe, for example, via this color hack. So this interface element was laid over our perceptions to allow us to gain the calories and nutrients we need to thrive and procreate.

Hoffman sums up as follows:

The [Fitness-Beats-Truth] Theorem tells us that winning genes do not code for perceiving truth. [Interface theory of perception] tells us that they code instead for an interface that hides the truth about objective reality and provides us with icons-physical objects with colors, textures, shapes, motions, and smells-that allow us to manipulate that unseen reality in just the ways we need to survive and reproduce. Physical objects in spacetime are simply our icons in our desktop.

How Deep Does the Interface Go?

Nobody knows how deep the interface goes. Hoffman concludes that we don’t need to see much if any of the truth underlying nature in order to thrive. In fact, it’s better if we don’t.

If there is an objective reality, and if my senses were shaped by natural selection, then the FBT Theorem says the chance that my perceptions are veridical–that they preserve some structure of objective reality–is less than my chance to win the lottery. This chance goes to zero as the world and my perceptions grow more complex–even if my perceptual systems are highly plastic and can change quickly as needed.

So, basically he’s saying we truth-seekers are generally screwed. Luckily for us, however, there is a caveat. That is, logic and mathematics are somehow part of our underlying reality. The universe, whatever it truly is, may throw up a phony interface all around us, but logic and mathematics do provide us clues about the underlying truth.

Why? Because even if we see that the apple is red, suggesting to us we should eat it, we still need to be able to know that taking two bites out of it is better than just taking one (or example). We don’t need to be great at mathematics, but we need enough basic logic to survive.

At least that’s his story.

Spacetime Is a Bunch of Hooey

Even so, Hoffman’s view is so radical that he thinks even spacetime is an illusory part of our interface. He loves to say (I’ve listened to a number of podcasts in which he’s interviewed) as well as write that “spacetime is doomed.” What he means is that our conceptual frameworks of space and time as we’ve known them since the age of Einstein have no underlying reality but are just the “interface” we use to negotiate reality.

To support his contention, Hoffman quotes theoretical physicist Nima Arkani-Hamed: “Almost all of us believe that spacetime doesn’t exist, that spacetime is doomed, and has to be replaced by some more primitive building blocks.”

Just to be clear, Hoffman does not deny that there is some “objective” reality that underlies our own, only that we do not have access to it. All we can do is use our reasoning, such as it is, to postulate about what that reality actually looks like.

That Way Lies Madness

When I listen to Hoffman on podcasts, his interviewers almost always express their concern that Hoffman’s argument potentially send us all down the path toward nihilism. That is, if everything we experience is just an illusionary interface, then how can we ever learn the truth of existence? And, if we can’t, then aren’t our lives meaningless?

Hoffman rejects that interpretation, saying that we can use our tools of scientific inquiry, mathematics and reasoning to learn more about “objective” reality, whatever that is. But I’m left wondering whether he’s adopting this stance because he fully believes it or because all his colleagues and the public at large would otherwise reject his theories out of hand.

Is Reason Reasonable?

After all, if spacetime is doomed, then why aren’t logic and reason? Logic is predicated on cause and effect, which are themselves contingent on the flow of time.

I imagine that, in the privacy of his own thoughts, Hoffman worries about this as well. On the other hand, so what if it’s true? Human beings as a whole are unlikely to ever embrace nihilism. We love our patterns and the sense that we know things. And, even without that evidence, we’ve shown ourselves perfectly willing to embrace faith: that is, belief without underlying proofs.

In the end, I worry less about people losing hope in their ability to understand some underlying reality than in their ability to embrace a faith that they then wish to impose on everyone around them. The latter leads to tyranny, intolerant ideology, zealotry and theocracy. For now, at least, those versions of faith seem by far the greater danger to us all.

Featured image is a Necker cube, which creates a kind of optical illusion in which the sides flip when you stare at it a while. From BenFrantzDale - Own work. https://en.wikipedia.org/wiki/Necker_cube

The Universe of Seurat and Rovelli

I was once chastised by security guard at the Art Institute of Chicago for getting too close to A Sunday Afternoon on the Island of La Grande Jatte, the greatest work by the greatest of the pointillist painters, Georges Seurat. I remember blushing with embarrassment as other patrons flicked their attention to me to take in the barbarian careless enough to endanger one of the world’s most beautiful and important works of art.

I also felt an initial rush of outrage that anyone would think I would harm such a treasure. But then I realized that was indeed too close, that my foot was over the line of the designated safe distance to the masterpiece, that I was indeed the Philistine they took me for. But I was a curious Philistine, looking closely to tease out how he was able to pull off his technique.

Pointillism, Atomism and Digitization

The art movement known as pointillism1 is the technique of applying small strokes or dots of paint so that from a distance so they visually blend together. Largely invented by Seurat, I think the technique visually demonstrates atomism, which Rovelli associates with certain Greek philosophers but was probably first described by the Vedic sage Aruni back in the 8th century BCE. Aruni proposed the idea that there were “particles too small to be seen [that] mass together into the substances and objects of experience.” 

Seurat aesthetically anticipated not only the atomic and quantum theories but the digital age in which we find ourselves living today, an age in which so many people spend the majority of their waking hours looking at screens of pixels.2 We are entranced by pointillism all day long.

In a sense, the idea of a pixelated universe is the topic of both Seurat’s work and Rovelli’s as laid out in Reality Is Not What It Seems: The Journey to Quantum Gravity? If you read the last post (or, better yet, the book itself) you should have at least a general notion of quantum gravity.

But what prospects does the theory have? How might it be supported by scientific evidence, and where might it lead us? Let’s discuss.

Vive la Révolution

Quantum physics was a revolution in physics, but what if Rovelli is right and all of spacetime is quantum? Well, then, the revolution is just beginning. Who really knows what knowledge it could bring us? Might quantum gravity help us better understand understand how to harness gravity itself? What new technologies could be created with it? Rovelli doesn’t discuss possible applications, but I can’t think of any major physics discoveries that didn’t also bring earth-shaking new technologies.

Testing Quantum Gravity

So, how can the theory be tested? One idea is to look for evidence of a “Big Bounce” as opposed to a “Big Bang” in the origins of the universe. According to Einstein’s view of the universe, all of spacetime could be squashed ad infinitum, ultimately leading to the Big Bang. But, that’s not what quantum gravity would predict. Rovelli notes that “if we take quantum mechanics into account, the universe cannot be indefinitely squashed.” And if that’s true, then we wouldn’t get a Big Bang but, rather, a gigantic rebound that he refers to as the Big Bounce.

So, how does one test that? Well, one can look at the statistical distribution of the fluctuations of cosmic radiation. That should provide evidence of the Big Bounce. In addition, according to Rovelli, “cosmic gravitational background radiation must also exist–older than the electromagnetic one, because gravitational waves are disturbed less by matter than electromagnetic ones and were able to travel undisturbed even when the universe was too dense to let electromagnetic waves pass.”

There’s also the prediction by the quantum gravity theory that black holes are not ultimately stable because the matter inside them cannot be squeezed into a single point of infinite density. Rather, at some point, the black hole explodes (like a miniature Big Bounce). If we can locate some exploding black holes in the universe, then we have more evidence of quantum gravity.

So, basically, if we find that super dense stuff is bouncing and rebounding in the universe, the quantum gravity folks might be right. If not, well, at least we’ll have evidence the theory is wrong and we can consider the other theories that have been, and surely will be, conjured up by the endlessly creative theoretical physicists.

If the quantum gravity champions do turn out to be right, then one of the side effects will be that the infinity goes away. Or, at least, physicists are a lot less likely to get infinity as the answer when they run certain calculations based on general relativity theory. The universe itself becomes “a wide sea, but a finite one.”

Bit by Bit, Information Becomes Reality

But don’t assume that, just because the universe might be finite, it doesn’t stay weird. In fact, it may start seeming weirder than ever if humanity succeeds in merging quantum mechanics information theory not only with the theory of relativity but with information theory.

First conceived by engineer and mathematician Claude Shannon in the mid-20th century, information theory assumes that information “is the measure of the number of possible alternatives for something.”

It was Shannon who popularized the word “bit” to mean a unit of information. He used it in his seminal 1948 paper “A Mathematical Theory of Communication,” and he attributed the origin to a Bell Labs memo written John W. Tukey, who used bit as an acronym of “binary information digit.”

Rovelli explains, “When I know at roulette that a red number has come up rather than a black, I have one ‘bit’ of information; when I know that a red even number has won, I have two bits of information…”

I won’t belabor this because information theory gets pretty complicated and Rovelli doesn’t go too deeply into it. To get a better but non-technical understanding, I recommend reading The Information: A History, a Theory, a Flood by James Gleick. I read it several years ago and hope to give it a second read over the next several months.

Anyway, it was John Wheeler, the father of quantum gravity, who was “the first to realize that the notion of information was fundamental to the understanding of quantum reality.” He coined the phrase “from it to bit,” meaning that the universe is ultimately made up of information.

Rovelli writes:

Information…is ubiquitous throughout the universe. I believe that in order to understand reality, we have to keep in mind that reality is this network of relations, of reciprocal information, that weaves the world. We slice up the reality surrounding into “objects.” But reality is not made up of discrete objects. It is a variable flux.

Although Rovelli has one more chapter on the scientific method, I think this is the better place to wrap up a post on a blog called The Reticulum. Let’s sum up: Reality is a network of relations among bits of information in a variable flux.3

I don’t know if that’s a true description of our underlying reality. But it does feel familiar: flux and foam, bits and bytes, indeterminacy and statistical spins. Even if quantum gravity doesn’t work out as epistemology, it still captures much of the essence of our baffling, vertiginous and often wondrous modern lives. 

1 The word pixel, by the way, is a portmanteau of "picture element," which is the smallest addressable and controllable element of a picture represented on a digital screen.

2 As visionary as the technique was, the term "pointillism" was actually coined by art critics in the late 1880s to ridicule Seurat and the other members of the art movement. But the artists, as they so often do vis-a-vis critics, got the last laugh. Today, the term is regarded as describing one of the great movements of neo-impressionism.

3 Which makes me think, of course, of Doc Brown's famous "flux capacitor."
Feature image: A Sunday Afternoon on the Island of La Grande Jatte by George Seurat: https://commons.wikimedia.org/wiki/File:A_Sunday_on_La_Grande_Jatte,_Georges_Seurat,_1884.jpg

Now You See Me, Now You Don’t

Out of the Frying Pan

So far, we’ve covered ancient atoms, electromagnetism and the theory of relativity. In Chapter Four of Reality Is Not What It Seems: The Journey to Quantum Gravity, we finally enter the last and strangest realm of known physics: quantum mechanics (aka, quantum physics).

In my last post, I compared trying to some to terms with the implications of Einstein’s model of reality to taking the red pill in The Matrix, leaving behind our comfortable (though false) notions of stable time and space in order to live in the bizarre, uncomfortable and yet often beautiful and exciting realm of spacetime.

Live free, Neo!

But entering the realm of quantum mechanics is something else. Just as you’re coming to terms with spacetime, you’re told that, by the way, spacetime is also a kind of matrix. An even stranger and more mysterious one. A matrix that isn’t populated by Agents trying to keep the truth from you but rather by gaggles of egghead physicists doing their damnedest to explain it to you….between their extended bouts of arcane squabbling.

Want to go back to your comfy pre-relativity matrix? Too late, Neo.

Into the Fire

So, let’s get down to explaining this new realm. Rovelli specifies that our quantum reality has three primary characteristics: granularity, relationality and indeterminism.

Hey, Why Is My Reality All Pixelated?

Let’s start with granularity. The short version is that, for the sake of convenience, a guy name Max Planck assumed that the energy comes in bite-sized (okay, smaller than that, but finite nonetheless) packets when doing his calculations.

Not long after, Einstein said something like, “Hey, you know what, Max? Energy really is made up of packets. What do you know!” (And, so, yes, the original Weird Al is one of the fathers of quantum mechanics and not just relativity).

Einstein claimed that this granularity extended to light, a form of energy. Most of the other physicists said, “No way! James Clerk Maxwell says light is a wave and waves don’t come in convenient bite-sized packets.”

To which Einstein said something like, “I guess it’s both! Beats the hell out of me how that could be true but let’s just go with it and see where it leads.”

And, wow, those breadcrumbs led to some very strange places…

Wait, They Were Just Here a Second Ago!

Next up is relationality, which is a boring name for something utterly bizarre. Rovelli sums it up in just three short sentences: “Electrons don’t always exist. They exist when they interact. They materialize in place when they collide with something else.”

So, you’re asking, how can that possibly be? Aren’t electrons just a part of an atom, like your arms and legs, nose and mouth are part of you? It’s like saying a person’s left arm doesn’t exist unless they happen to bump into somebody else. How does that work? you ask. I haven’t a clue, but electrons are apparently just ghosts that appear during interactions with one another.

Even though it was his personal bread crumb trail, Albert Einstein thought this was all too strange to be true. But there’s this other physicist, Paul Dirac, who didn’t seem to have problems with it. Rovelli writes, “For him the world is not made of things; it’s constituted of an abstract mathematical structure that shows us how things appear, and they how behave when manifesting themselves.”

Speaking of the problems posed by Dirac, Einstein groused, “To maintain an equilibrium along this vertiginous course, between genius and madness, is a daunting enterprise.”

Rovelli indicates that objects (though what really constitutes an object?) can still have characteristics such as mass while they are not interacting with one another, but the object’s “position and velocity, its angular momentum and its electrical potential only acquire reality when it collides–interacts–with another object.”

Okay, can it get any weirder? Glad you asked!

I’ve Determined that I Can’t Determine

Last up is indeterminacy. Einstein hated this part. He famously said, “God does not play dice with the universe.”

What he objected to was the fundamental quantum physics idea that one cannot predict what any given particle is going to do. Rovelli wraps it up like this: “While Newton’s physics allows for the prediction of the future with exactitude, if we have sufficient information about the initial data and if we can make the calculations, quantum mechanics allows us to calculate only the probability of an event. This absence of determinism at a small scale is intrinsic to nature.”

“Intrinsic to nature” — let that one sink in. All you can do is give and get probabilities. It’s all a big dice game, as far anyone can tell.

Or maybe it’s a baseball pitcher with lousy ball control. For some reason, I think of the movie Bull Durham in which the rookie pitcher Nuke can throw hard but doesn’t know where any given pitch is going to go. “Hell if I know where the damn thing’s going…” Nuke’s catcher, Crash, tells a nervous batter. (And, yes, Bull Durham fans, I know it’s a ploy on Crash’s part but, hey, it’s just a metaphor).

Anyway, what Dirac’s equations can do is give you a range of the possibilities and then a calculation of the probabilities within that range (At least, I think that’s right, based on what I can determine. Get it? Determine. Indeterminacy? Ok, never mind).

We Cobbled Her Together But She Sure Does Run Good

Over the years, physicists “cobbled together” (Rovelli’s phrase) what we now call the Standard Model (physicists are crap at naming and marketing, it appears). He sums up:

The Standard Model is completed by the 1970s. There are approximately fifteen fields, whose quanta are the elementary particles (electrons, quarks, muons, neutrinos, Higgs, and little else), plus a few fields similar to the electromagnetic one, which describe electronmagnetic forces and the other forces operating at a nuclear scale, whose quanta are similar to the photons.

The thing is, this junky heap of particles, fields, equations and whatnot turn out to be extremely robust and fast around the corners. Experiments keep confirming it and engineers depend on it to build all our fancy electronic gadgets. In the end, it’s the model that everybody buys.

Now Comes the Hard Part

So, quantum mechanics works like a charm. But so does Einstein’s theory of relativity. The problem is that the two explanations don’t work well together. One works super well in the macro world and one works super well in the micro world, but nobody knows how to marry the two.

So, that’s where Rovelli and others come in. They want to settle these irreconcilable differences by building a house that both theories can comfortably fit in. Heck, they want more than that. They want our two theories spooning each other, finishing one another sentences, lovingly telling us stories of how their many zany antics and impassioned conflicts finally ended in a Harry-and-Sally-type romance that we can all laugh about now.

So, will they or won’t they? Stay tuned. Next week: Falling For Quantum Gravity

Feature image: Clara Ewald's portrait of Paul Dirac: From https://commons.wikimedia.org/wiki/File:Clara_Ewald_-_Paul_Dirac.jpg

Einstein and the Big Squid

Taking the Red Pill of Relativity

Now things get weird. In the first post about Rovelli’s Reality Is Not What It Seems, we focused on atoms. Despite the strange fact that medieval Christians tried to censor the concept of atoms, they do not score very high on my weird-shit-o-meter. I was brought up with them, so they seem as friendly as eating potato chips on a comfortable couch.

In the second post, we got into electromagnetism. But, considering that most of us live enmeshed in cocoons of wire and wifi, it’s hard to see that topic as outlandish, however much our forebears would have been astonished.

But in Rovelli’s third chapter, the topic of this post, we’re forced to choke down a red pill if we want to enter the spacetime reality of Albert Einstein’s mind, thereby exiting The Matrix of our comfortable everyday reality where time and velocity seem as easy to grasp as a digital readout.

You’d think that by now we’d be accustomed to the original Weird Al’s big brain. I mean, we’ve had a century or so to get acclimated to this stuff. But, speaking for myself, I’m still struggling to cope with the idea that the world is not what it seems.

Present But Not Accounted For

Rovelli tries. But, despite the cartoons, his section on the “extended present” is hard to swallow. How and why has the present moment been extended by the Special Theory of Relativity?

I assume it has to do with the speed of light and relative time, but you’ll need to take it on faith within the context of this chapter. Here’s an example:

[O]n the moon, the duration of the extended present is a few seconds, and on Mars a quarter of an hour. This means we can say that on Mars there are events that are yet to happen, but also a quarter-of-an-hour of events during which things occur that are neither in our past nor in our future.

I find this hard to wrap my brain around and wish Rovelli had gone to greater lengths of explain the details. I remember getting a deeper glimpse of time relativity when pondering the ideas in the book Why Does E=mc2 (And Why Should We Care?), but I’ve since lost it (the glimpse, not the book). And now I’m wondering if I’ll need to bear down on that text again in order to grasp Rovelli’s arguments. We’ll see.

Space Is a Monster Mollusk

Okay, let’s put the “extended present” into a box (perhaps along with Schrodinger’s cat) and come back later to see what happened. For now, I want to focus on another statement in Chapter Three:

What if Newton’s space was nothing more than the gravitational field? This extremely simple, beautiful, brilliant idea is the theory of general relativity…. Newton’s space is the gravitational field. Or vice versa, which amounts to saying the same thing: the gravitational field is space….We are not contained within an invisible, rigid scaffolding: we are immersed in a gigantic, flexible mollusk (the metaphor is Einstein’s).

Okay, despite the Cthulhu vibe, I understand this better than the concept of extended present. I get the whole spacetime-curved-by-big-hunks-of-matter idea. I get that everything’s moving and has speeds only relative to everything else and everything is in constant flux. I even kind of (though not really) get the idea that time flows faster at the top of a mountain rather than in a valley.

But spacetime is the same thing as the gravitational field? Was that originally part of the Theory of Relativity? Apparently I’m not the only one confused. I wonder if that’s part of scientific history or just a tenet of the quantum gravity hypothesis, which is the ultimate subject of the book.

A Universe Designed by Escher

The latter sections of Chapter Three are mostly focused on how the universe may be a humongous globe with an extra dimension stuck in there. Einstein conceived a way in which the universe might be finite while still having no discernable boundary. Rovelli uses the metaphor of a globe:

On the surface of the Earth, if I were to keep walking in a straight line, I would not advance ad infinitum: I would eventually get back to the point from which I started. Our universe could be made in the same way. I fly around the universe and eventually end up back on Earth. A three-dimensional space of this kind, finite but without boundary, is called a “3-sphere.”

Although he goes on for another 12 pages or so, for me the above is the essence of the discussion. And, I kind of get it, or at least think I do, because we all understand the metaphor of the globe. Whether I can can truly conceive the shape of the universe like this, however, is another matter. It’s something to work on.

It’s Networks All the Way Down

Boiling it all down, I take away two main insights from this chapter. First is the idea that space as we (or at least I) sometimes think of it doesn’t exist. There are no vast empty spaces in space. It is jam-packed with gravitational and electromagnetic fields light waves, radio waves, gamma rays, microwaves, etc. In fact, maybe space is nothing more nor less than an unthinkably immense gravitational field.

Whatever space is, however, it’s certainly not mostly empty. It is a packed and fluctuating landscape in its own right. Jupiter is a not a planet but a mountain, one that we can climb and look down at the curved and rippling real estate of our solar system, if we’re willing to see beyond the merely visible.

My second insight is that network describes the scene even better than landscape. In my mind’s eye, I see block-and-tackle pulleys everywhere, connecting everything in our solar system (and the greater universe, of course) in a constantly shifting network.

Some mythologies have it that the Earth is supported on the back of a giant World Turtle. But what does the turtle stand on? There’s the old joke that, well, it’s “turtles all the way down” in a kind of infinite regress.

Perhaps it’s less of a joke to say that the universe is a network of networks. What do the networks attach to? Well, other networks via gravitational forces. I guess we could say it’s networks all the way down.

Featured image: Artist's concept of the Interplanetary Transport Network. The green ribbon represents one possible path from among the infinite number possible within the larger bounding tube. Constricted areas represent locations of Lagrange points. Wikimedia Commons

Minding the Universe

I read an article about how a study finds similarities between the human brain and networks of galaxies in the universe. Maybe we should be minding the universe a bit more carefully if it truly is, as the playwright once said, the mind of God.

Camerae Ready

Surprising? I don’t know. It seems as if the universe uses a lot of its same basic structures over and over at different scales, and these structures often have mathematical counterparts. One of the more famous examples is the Fibonacci sequence, in which each number is the sum of the two preceding ones, starting from 0 and 1. That is, 0 + 1 = 1, 1 + 2 = 3, 2 + 3 = 5, 3 + 5 = 8, 5 + 8 = 13, 8 + 13 = 21, etc. So, the actual sequence looks like 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, and on and on.

What’s interesting is that this pattern shows up with some frequency in nature. Perhaps the most robust and convincing example is the spiraling nautilus shell, which is composed of chambered sections called camerae. Each chamber is equal to the size of the two camerae before it, creating a logarithmic spiral.

But there are there other examples as well: tree branches, flower petals, the seeds in sunflowers. It may extend to much larger phenomena as well, such as hurricanes and spiral galaxies.

So, perhaps it should not be surprising to find that brains and the universe are largely defined by their networks (that is neurons and galaxies) made up of nodes connected by filaments. In short, both are kinds of reticula. To read the actual report, go here.

Assuming the authors have a legitimate point, what do we make of the similarities between the universe and the human brain? Are we supposed to consider the idea that the universe is itself a thinking organism of some sort, that we exist in the mind of God?

Panpsychism

That’s too great a logical leap for me to make, but maybe it does lend support to the pseudo-scientific notion that the universe is conscious. In his book Galileo’s Error: Foundations for a New Science of Consciousness, philosopher Philip Goff considers the idea that consciousness is not something special that the brain does but is instead a quality inherent to all matter, a theory known “panpsychism.” To read an interview in which he discusses the notion, go here:

 Goff isn’t alone in wondering about the consciousness of the universe. Astrophysicist Ethan Siegel has discussed it in Forbes, and NBCNews highlights other thinkers in its article “Is the Universe Conscious?”

I don’t know what to think about all this. It feels a bit like the Gaia hypothesis (which is the idea that the interconnected biological systems of the Earth act as one, enormous organism), except extended to “infinity and beyond” (in the immortal words of Buzz Lightyear).

Our Town

Back in my college days, I was in a staging of the play Our Town, in which I played the character George. I don’t remember many of George’s lines but I do remember a scene in he was speaking with his sister Rebecca at the end of Act One:

REBECCA: I never told you about that letter Jane Crofut got from her minister when she was sick. He wrote Jane a letter and on the envelope the address was like this: It said: Jane Crofut; The Crofut Farm; Grover’s Corners; Sutton County; New Hampshire; United States of America.

GEORGE: What’s funny about that?

REBECCA: But listen, it’s not finished: the United States of America; Continent of North America; Western Hemisphere; the Earth; the Solar System; the Universe; the Mind of God–that’s what it said on the envelope.

GEORGE: What do you know!

REBECCA: And the postman brought it just the same.

GEORGE: What do you know!

I doubt Thornton Wilder was the first writer or mystic to envision the universe as the mind of God. But I do wonder what he’d think about the fact that here in the third decade of the 21st century, it has become an idea taken seriously by the likes of philosophers, physicists, and science journalists. What do you know! 

Featured image from https://en.wikipedia.org/wiki/File:NautilusCutawayLogarithmicSpiral.jpg. Nautilus shell cut in half. Photo taken by Chris 73 | Talk 12:40, 5 May 2004 (UTC)