6. Physical Reality: Hitting Rock Bottom?
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“If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it.”
― Albert Einstein
“Those swirls in the cream mixing into the coffee? That’s us. Ephemeral patterns of complexity, riding a wave of increasing entropy from simple beginnings to a simple end. We should enjoy the ride.”
― Sean Carroll, American physicist and philosopher, in "The Big Picture"
As noted in the previous chapter, Physical Reality is one of the axioms that the MSE Framework rests on. It is self-evident to us and fundamental, but we do not know how it emerges from The Great Unknown.
Physics has been immensely successful in explaining a huge part of physical reality. In fact, Physics is the most successful science of all in terms of its reliability, accuracy and scope, and, as a result, we rely on it heavily to build the MSE Framework.
Well-known physicist and philosopher Sean Carroll says in his book “The Big Picture” that Physics has allowed us to completely describe “everyday physical reality”, i.e., the part of physical reality that we interact with on a regular basis.
Note that this fits in nicely with our methodology of Present-Bounded Rationality, where we focus primarily on the here and now, not on distant phenomena occurring either long ago or in the far future, or indeed, in some galaxy, far far away.
Carroll has put together a single equation that captures everything we know about our everyday physical reality, including quantum mechanics, spacetime, gravity, matter, the Higgs particle and all the forces of nature. He calls it the Ultimate Equation of “Everyday” Physics.
We don’t need to go into the details of this equation (there is tons of material available on it elsewhere), but just marvel at our accomplishment as a relatively young species on a small little planet somewhere in the unfashionable part of the universe with the audacity to want to decipher the true nature of reality from our ridiculously narrow perspective!
If we can do that, cracking the code of meaning, purpose and hope should be a walk in the park for us, right?
Ok, to sober us up a little from that bit of chest thumping, let me mention that, in spite of this wonderful equation, there still are some major gaps in our understanding of physical reality.
Here are some of the aspects of physical reality that we are currently unable to explain fully:
Non-everyday physical reality i.e. things like Dark Matter / Dark Energy, very early parts of the Big Bang, how the universe may end, many aspects of Black Holes, etc.
The “fine-tuned universe” problem i.e. why the universal constants that appear in physics have the values they have and why even slight variations in their values would have led to us, or even the whole universe, not existing.
While there are a lot of discernible patterns in physical reality, there is also a lot of nebulosity. A great example is clouds - we are unable to capture them in terms of mathematical equations due to them being fuzzy, ill-defined, constantly changing, and appearing different from different distances.
We experience a lot of complex phenomena that emerge from simpler phenomena, and while we may be able to say a lot about the simpler as well as the complex phenomena, we are unable to derive the latter from the former. This is known as Emergence. An example of this is the phenomena of temperature and pressure emerging from the movement of molecules of a gas.
As noted in the previous chapter, how physical reality and consciousness as well as The Great Unknown interact with each other is unknown.
For now, we will simply make note of the fact that physics, and science in general, has some limits, but we have found ways of making do with what we can do, using our methodology.
In any case, we do not need to know everything to define the MSE Framework. Apart from the basics, like matter and energy, we only need a few other concepts from the entire body of physical sciences. Let us take a look at them below.
(This is a general practice in this book, we will quickly get an overview of each topic, but then talk in greater detail only about the concepts that matter to the MSE Framework.)
As noted earlier, physical reality contains both many discernible patterns as well as a lot of nebulosity.
Patterns include things like the laws of physics that we have discovered. They also include the elementary particles with specific properties, the specific ways they combine to form atoms and then molecules, the forces that act on them, and so on.
Through painstaking work, we have managed to discover many such patterns in physical reality. But we also know that not everything in physical reality is patterned in this manner. There is also a lot of nebulosity.
Nebulosity includes things like clouds, the shapes of various bodies of water, the shapes and structures of sunflowers, the arrangement of hair on bees’ legs, the irregularities in the structure of bee hives themselves and so on.
Even things that appear patterned at the macroscopic level may actually be quite nebulous at the microscopic level.
Nebulosity could be inherent to the physical phenomenon, or it could be a result of our inability to figure out a pattern or inability to compute it because it would be too computationally expensive.
Another interesting and related phenomenon is emergence, where, as described earlier, new patterns emerge from simpler patterns but we are unable to derive one from the other and there is a range of nebulosity in the middle.
For many of the parts of physical reality that are patterned, we have been able to discover incredibly accurate mathematical formulas. And for many of the things that are nebulous, we have developed and continue to develop heuristics, tacit knowledge, practices and technologies that help us deal with them to the extent possible.
Science deals with the patterned aspects of physical reality and, in order to deal with the nebulous aspects, we can add engineering into the mix. As we have noted already both of these are parts of the methodology of Present-Bounded Rationality.
As a result of amazing feats of intellectual ability and effort, human beings have been able to discover that, at the lowest level of physical reality, we have what appear to be a set of quantum fields that permeate all of space.
While we haven't been able to observe the quantum fields themselves, we have managed to figure out how to characterize them, using what is known as a quantum wave function. We have been able to discover an equation known as the Schrödinger Equation, that we can use to determine how a quantum wave function evolves. For example, it allows us to determine the probability distribution of a particle existing at any point at a given point of time.
But the really interesting part about quantum wave functions is that they don't remain as seemingly ephemeral wave functions forever. They can “collapse” and give rise to concrete physical particles that we can observe or measure. These particles make up what we typically call “matter”, though one could extend the definition to include the quantum fields themselves.
If this collapse, known as “quantum wave function collapse” did not occur, we would have only probability distributions and nothing definite would occur anywhere in the universe. But, fortunately for us, such collapses do occur and they lead to definite things occurring in what we call our “classical” reality.
While there are many unknowns about the phenomenon of wave function collapse, what we know for sure is that they are constantly occurring an uncountable number of times all over the universe.
One can interpret this ubiquitous and ever-present phenomenon as the universe appearing to have a “natural tendency” for creating definite or concrete particles from foggy wave functions.
And this tendency isn't limited to just the wave function level either.
Various types of wave function collapses give rise to the creation of a variety of elementary particles. These elementary particles, in turn, come together to form protons, neutrons, electrons, atoms and molecules that form the basis of all physical reality.
At a higher level, clouds condense into droplets of rain. Billions of such drops come together to form puddles, which combine into streams, which combine into rivers and eventually oceans.
Also, all over the universe, huge clouds of hydrogen have been coming together (and are continuing to come together) over long time frames to form stars, or other material coalesces into planets.
Even inside our heads, foggy thoughts often collapse into concrete ones.
What I am trying to get at is that this same universal tendency can be observed in various domains, contexts and levels.
As a result, we can make a general statement that the universe appears to have a natural tendency to create concrete things from nebulous or foggy things.
So, let us go ahead and create a formal statement of this universal tendency, which we will call “Coherence”.
The universe appears to have a natural tendency to create definite or concrete things out of uncertain or foggy things.
(Note that the phenomenon of wave function collapse is also known as “quantum decoherence” in physics, but here we are calling it "coherence". This unfortunate naming contradiction occurs because, from the point of view of the quantum field, the wave function collapse can be seen as "decoherence". But from the classical physics side where we observe it, it can be seen as the quantum fog, in some sense, "cohering" to form concrete elementary particles.)
In addition, it is important to note that evidence of this universal tendency can be observed everywhere and all times, including right here, right now. There is no need to go to the uncertain beginning or end of the universe to make this observation.
Finally, you may have noticed above that I have given a number to this tendency: #1. As you might have guessed, we are going to build a list of such tendencies over the next few chapters and see what we can do with them.
Unfortunately, while the universe does give us this wonderfully beneficial tendency of coherence, it also gives us our most formidable enemy, entropy.
Informally, entropy is considered to be a measure of disorder in a system.
However, this informal definition hides some critical nuances, so it is important to look at a more formal definition.
A more formal definition is that entropy is a measure of the number of different ways you can arrange small-scale entities with certain properties (known as microstates) that give rise to the same large-scale properties (known as macrostates).
For example, the number of ways you can arrange air molecules in a box to get the same volume of air at the same temperature and pressure.
Next, let us observe that, for any such system, there is a much larger number of ways for being disordered than being ordered. As a result, the probability of finding the system in a highly disordered state is much higher than the probability of finding it in a highly ordered state.
This is the same as saying that the probability of finding a system in a high entropy state is much higher than the probability of finding it in a low entropy state.
This purely statistical fact is what gives rise to the Second Law of Thermodynamics which says that entropy can only increase over time. This is simply a result of the fact that phenomena with low probability will be replaced with those with higher probabilities over time.
Luckily for us, the universe began in a very low entropy state and its entropy has steadily been increasing ever since. If the universe had begun in a very high entropy state, nothing much would be happening today.
Unfortunately, what this means is that the universe will continue to get more and more disordered over time, eventually leading to what has been named "the heat death" of the universe, when nothing interesting or meaningful will ever happen.
This idea, combined with our mistaken notion that meaning and purpose can only be discovered "at the end", has been used to imply that any attempt at defining meaning and purpose using science is doomed. Moreover, it is all hopeless in the end.
This idea has insidiously percolated through our thinking, giving rise to claims of science being ultimately nihilistic and unable to address our desire for meaning, purpose and hope.
The fundamental problem here is the assumption that meaning, purpose and hope can only come from something that happens “in the end”, presumably when we meet our "maker".
This is clearly another leftover idea from our belief in religion. This is because, in many religions, there is a “judgment day at the end”, when one finally gets to meet their maker and gets judged for their behavior during their life.
But, as we stated in the description of our Mindful Bounded Rationality methodology, we do not need to speculate on some highly unpredictable “end of time” moment in order to find meaning. Instead, we build everything from what we know for sure, which is the present moment, right here, right now.
So, we have no reason to believe that science is nihilistic. We can find plenty of meaningful things right here, right now, even through the medium of science.
For example, while we do have the worrying universal tendency towards increasing entropy, we also have an ally that helps us fight it. This ally, which can be called a big sister to the universal tendency of Coherence that we saw earlier, is Complexity.
Let us take a look at that next.
Complexity is a measure of how hard it is to describe the set of properties of a system. Simple systems are easier to describe, or require less information to describe, than complex ones.
This is because the complexity of a system depends upon the level of organization or structure within a system. A complex system has many interacting components, and this can lead the system to exhibit emergent behavior or properties that are not apparent from examining the individual components in isolation.
As we saw earlier, physical reality consists of a wide diversity of elementary particles, atoms and molecules displaying a wide variety of properties as well as the variety of forces that they are subject to. They are constantly moving and interacting with each other. Many of these interactions result in them coming together in various ways, giving rise to more complex forms from simpler ones.
This process is ongoing. In stars, simpler atomic nuclei are constantly combining to form larger ones. On planets, simpler molecules are combining to form more complex ones, including really really complex ones such as proteins, RNA and DNA. On a higher level, many single cells are coming together to form organisms, organisms into societies, societies into entire ecosystems and so on.
At each level, it gets harder to describe the structure and set of properties of the system, i.e., the complexity of the system increases.
The vast majority of this happens spontaneously. This tells us that the universe, by itself, appears to have a natural tendency towards creating more complex things and organizing them in increasingly complex patterns.
There is even a deeper and more rigorous explanation for this tendency, particularly when living organisms are involved. We will look at that in the next chapter.
For now, let us formalize this ubiquitous and ever-present tendency by adding it to our list.
The universe appears to have a natural tendency to form more complex structures out of simpler ones.
As you may have noticed, the first two Universal Tendencies, Coherence and Complexity, can be seen to overlap a bit, but each one also captures something unique that is not captured by the other. There may be a way to refactor the list of tendencies so there is no overlap, but for now, this is fine for our purposes.
Also note that I am stopping short of calling these tendencies as “laws”. This keeps the list informal and in keeping with our “satisficing” methodology.
In fact, and rather disappointingly, we do have a well-known "law" for the other universal tendency, Entropy. I am talking about the Law of Entropy of course, and it is considered to be one of the most ironclad laws of reality.
But lately, many scientists have been working on defining a new "law" that formalizes some of these universal tendencies that work in the opposite direction to entropy. I look forward to such efforts leading to a new law that is as powerful as the law of entropy. I have included a Deep Dive into one such effort below.
Note that I am not including Entropy in the list of universal tendencies that we are building. Needless to say, it is one of the most well-known tendencies of the universe, but this tendency goes in the opposite direction of our ultimate objective of defining meaning, purpose and hope in a rigorous manner. The list we are building isn't intended to be a definitive list of all universal tendencies. It is going to contain just the ones that we need for our purposes.
Coming back to Complexity then, let us note that the phenomena of entropy and complexity appear to be engaged in a kind of a cosmic dance, bringing matter together and taking it apart.
This dance turns out to be one of the most meaningful things in the universe as we will soon see.
As a first approximation, let us note that, informally, things that are less chaotic have low entropy and those that are more chaotic have higher entropy. But this is also true of complexity: things that are less chaotic look less complex and those that are more chaotic look more complex.
So, one might be tempted to conclude that entropy and complexity have a linear relationship i.e., as complexity increases, entropy also increases, and vice versa.
This may make sense because more complex systems have a greater number of possible arrangements of their components that are consistent with their macroscopic properties, and thus have a greater number of microstates, which imply a higher level of entropy.
However, it's important to note that complexity and entropy are not the same thing, and that they have a more complicated relationship.
Let us look at an example that illustrates this fact.
Imagine taking a glass of water and placing a drop of ink into it.
Before the ink drop touches the water, the combined system consisting of the water and the ink starts off in a state with relatively low entropy as well as complexity – all the molecules in the ink drop are uniformly distributed inside the ink drop and all the molecules of water in glass are uniformly distributed in the glass. This is because they haven’t started mixing yet.
As the ink starts to disperse throughout the water, the entropy of the system goes up because now there are more ways in which the ink and water molecules could be arranged together than before.
The ink drop transforms into a set of complex and expanding swirls, slowly dispersing through the water.
This means that the complexity of the system also increases. This is because complexity is a measure of how hard it is to describe the set of properties of a system, and a system with complex swirls of ink dispersing through the water would be more difficult to describe than one where they were bounded within their own volumes.
As the ink continues to spread throughout the water, the entropy of the system keeps going up, until the ink is uniformly distributed in the water.
Eventually, the ink and water reach an equilibrium. But this equilibrium is once again simple to describe: It’s just a homogenous mixture of ink in water, which means it is once again less complex.
So, in this case, while the entropy of the ink+water system kept continuously increasing, complexity, which was initially growing, reversed course at some point and decreased, eventually becoming small again.
The following graph shows this relationship.
Not to reveal any spoilers, but this interesting relationship between entropy and complexity turns out to be the largest source of meaning, and even purpose, in the universe!
But, like we have said, we will get there step by step, but ferociously.
Keep this picture of ink mixing into water in mind. We will encounter it again in the next chapter where we talk about one of the most important topics discussed in this book, Life.
Sean Carroll is a well-known physicist, philosopher and podcaster. He has written a book called The Big Picture, which talks about his model of ultimate reality, which he calls Poetic Naturalism.
In short, Poetic Naturalism can be described as follows:
Physical reality is mostly explained by the Standard Model of Physics, except for some areas at the low and high extremes, such as black holes, deep space and the Big Bang. (We already talked about this when we looked at the ultimate equation of physics, and, in fact, the ideas on this were taken from the book mentioned above.)
Beyond physics, different explanations exist for different sections of reality. For example, we have biology with its own laws of evolution, genetics, etc. Above that, we have psychology and then sociology, with their own laws and principles.
How we transition from the lower layers of this hierarchy to higher ones is currently not known. These transitions, known as phase transitions or emergence, cause gaps in our understanding of reality and, as a result, a unifying theory of everything remains elusive.
So, Sean’s proposal is that we should simply say that there are many ways of talking about the natural world and some of those are still very valuable in their respective domains.
For example, the fact that the underlying laws of physics are deterministic and impersonal does not mean that at the human level, we can’t talk about ideas about reasons and goals and purposes and free will.
In other words, while fundamentally this is still Naturalism, there is an element of poetic perspective in it. Hence, he calls it Poetic Naturalism.
As mentioned above, many scientists have noticed that the universe has some natural tendencies that go in the opposite direction to the law of Entropy.
Here is a reference to and an abstract from one such recent effort:
"On the roles of function and selection in evolving systems" by Michael L. Wonga, Carol E. Cleland, Daniel Arend Jr., Stuart Bartlett, H. James Cleaves II, Heather Demarest, Anirudh Prabhu, Jonathan I. Lunineg, and Robert M. Hazen in Proceedings of the National Academy of Sciences, Volume 120, Issue 43, Oct 2023.
"The universe is replete with complex evolving systems, but the existing macroscopic physical laws do not seem to adequately describe these systems. Recognizing that the identification of conceptual equivalencies among disparate phenomena was foundational to developing previous laws of nature, we approach a potential “missing law” by looking for equivalencies among evolving systems. We suggest that all evolving systems—including but not limited to life—are composed of diverse components that can combine into configurational states that are then selected for or against based on function. We then identify the fundamental sources of selection—static persistence, dynamic persistence, and novelty generation—and propose a time-asymmetric law that states that the functional information of a system will increase over time when subjected to selection for function(s)."
