top of page

“One cannot help but be in awe when he contemplates the mysteries of eternity, of life, of the marvelous structure of reality. It is enough if one tries merely to comprehend a little of this mystery every day.”  - Albert Einstein


  • Instagram
  • TikTok
  • Youtube

Guided Investigations

Long Reads

Part 1: What's the Matter

Updated: Jan 28

Physicist Niels Bohr: “If quantum mechanics hasn’t profoundly shocked you, you haven’t understood it yet. Everything we call real is made of things that cannot be regarded as real.”

Let's begin our investigations into the nature of our reality with one simple question: what is matter made out of?

When physicists first started examining atoms, they envisioned them as being made up of smaller and smaller bits of matter, but as they peered into the subatomic world they stumbled upon a completely different reality.

Something mysterious was going on at a subatomic scale, as if atoms were following a different set of rules altogether.

Physicist Richard Feynman: “Working out another system to replace Newton’s laws took a long time because phenomena at the atomic level were quite strange. One had to lose one’s common sense in order to perceive what was happening at the atomic level.”

Up until that point physics described how our everyday experiences were governed by a very precise set of rules, now referred to as Newtonian or classical physics, which still does a great job of describing the world around us. When physicists began to examine light more closely things got weird.

The first-ever image of light behaving both as a particle and a wave from 2015

Before the discovery of the atom, physics described a reality that resembled our everyday experience of light and matter, where they are independent and fundamentally different from one another.

Instead, light was found to be two things at once, a nonphysical wave that could also mimic the particle behavior of matter, and the boundaries between them began to break down.

It all started back in 1900 when German physicist Max Planck discovered that light was behaving in two different ways, being both spread out and condensed. A few years later Albert Einstein expanded on Planck’s work, publishing a paper describing an effect where light can kick out the electrons of matter, arguing that the effect was the result of the particle-like behavior of light.

Einstein: “We have two contradictory pictures of reality; separately neither of them fully explains the phenomena of light, but together they do.”

By the 1920s physicists had discovered that the double nature of light also applied to matter. They found matter to have wave-like qualities, although not like a conventional wave. Matter behaves according to an abstract mathematical model, called a wave function, that describes an array of possible particle behavior.

We perceive the world around us as being mostly fixed and constant, but what goes on under the hood of reality is filled with uncertainty.

Imagine an electronic dart board covered in holes, all the possible places that darts could land. Matter is like an empty dart board until something happens, some kind of interaction, and then wallah, the darts are on the board. What exactly happened to make the darts land in those specific places? Now that's the million dollar question.

Orbital regions where electrons are likely to be found in a hydrogen atom

The particles that make up matter exist only as possibilities until some kind of interaction occurs. Only then does this uncertainty collapse into a specific reality. The chair becomes the chair, the table becomes the table, and the world seems ordinary and understandable.

When we dive in deep enough, reality is just a set of instructions for how things could be built given particular circumstances. In effect, we have zoomed into matter only to find it dissolve right before our eyes.

Our energetic universe

Most of us were taught in school that the nucleus of an atom is a tiny dense ball at the center of the atom, although in actuality the nucleus is an extremely concentrated fluctuating blur of energy, holding itself together with world destruction levels of energy.

Even still, it’s the atom’s electrons that are the strangest and most enigmatic. Electrons are mysterious little shapeshifters, continually orbiting, spinning, tunneling, and doing other curious things that scientists don’t yet understand.

An object feels solid to us because the electrons in atoms dance, not randomly, but in distinct patterns, as with synchronized dances or the movement of a flock of birds. What appears to us as a solid object is just a cloud of subatomic particles moving in special ways relative to one another, which together produce the experience of something solid. Light interacts with these clouds, preventing us from seeing through the object.

Electrons move in complex fluctuating patterns similar to how starlings undulate and move together in large flocks

Particles are not tiny billiard balls darting around the nucleus, but rather areas of excitations within fields of energy that stretch throughout the universe.

As we go about our daily life, all we are ever really experiencing is energy interacting with other energy.

If you think all of this sounds overwhelmingly ephemeral, elementary particles are even more fleeting. Supercomputers have revealed that atoms are filled with previously undetected fields of elementary particles that fluctuate in and out of existence, like ghosts appearing out of nowhere only to disappear again, revealing a mysterious process of continuous creation and annihilation.

Visualizations of Quantum Chromodynamics from the University of Adelaide, Australia

The deeper physicists look, the more elusive the physical world is. We are quite literally living in a reality of philosopher-level abstraction.

Physicist Max Born: “I am now convinced that theoretical physics is actually philosophy.”

“Energy is the ability to do work.”

Textbook descriptions of energy are practical observations of everyday physical interactions that are overwhelmingly specific, while also being vague about what energy actually is.

Physicist Richard Feynman: “It is important to realize that in physics today, we have no knowledge of what energy is.”

Apples fall because of gravity, thermal energy melts ice cubes, our bodies consume food to get chemical energy, our legs use mechanical energy to kick a ball, electrical energy keeps the lights on, and nuclear fusion keeps the sun shining.

At its most basic, energy is the ability to self transform or produce changes outside of oneself. It is a mathematical description of interactions that are either consuming or releasing this ability to do something, and all doing something ever really means is that things are being moved around. Turns out, the universe doesn’t like to sit still.

Albert Einstein: “Nothing happens until something moves.”

The universe’s built-in ability to do something keeps on doing stuff, again and again, just in different forms, a process described famously by the Greek philosopher Heraclitus: “The only constant in life is change.”

While kinetic energy is related to motion, or movement through space, potential energy is related to location, or positions within space. Kinetic energy is the amount of change or movement that can be done, while potential energy is the potential for change or movement to happen, a kind of frozen energy.

Potential energy is baked into matter, as Einstein famously described with E=mc2, also called mass-energy equivalence, because mass and energy are just different manifestations of the same thing.

The energy inherent to matter is so immense that converting the atoms of a single paper clip into pure energy would yield 18 kilotons of TNT, roughly the size of the bomb that destroyed Hiroshima in 1945. It’s as if our low-energy environment here on earth is a kind of freeze frame of high-energy states.

All of this paints a picture of energy as a kind of fundamental process that is frozen inside of mass, with matter being like a photo of the event, rather than the event itself. As it turns out, matter isn’t full of stuff, but rather full of the potential for stuff to happen.

Relatively universal

Physicist Leonard Susskind: “Einstein, in the special theory of relativity, proved that different observers, in different states of motion, see different realities.”

In 1905 Einstein was working as a patent clerk in Bern, Switzerland, pondering the truths of the universe each night after he got home from work, because well, he was Einstein. The streetcar that he took daily ran next to the Zytglogge clock tower, which would one day inspire him to devise a thought experiment that would end up changing physics forever.

At the time scientists were stuck with a seemingly insurmountable paradox. On the one hand, Isaac Newton’s laws of motion insisted that speeds are never absolute, but always measured with respect to something else.

For example, if two cars are traveling side by side at the same speed, the occupants of each car are motionless with respect to one other, while someone standing on the side of the road would just experience a blur of motion.

A few hundred years after Newton, mathematician James Clerk Maxwell came along, and discovered that electricity, magnetism, and light are all different manifestations of the single phenomenon of electromagnetism, devising equations along the way that showed the speed of light to be absolute, always traveling at a constant speed, regardless of who observed it.

How could the speed of light be fixed in a world of relative movement?

If the speed of light was to be truly absolute, then something about our notions of space and time would have to change.

Einstein pondered what would happen if his streetcar raced away from the clock tower at the speed of light. With the speed of light constant, something else would have to happen in order for the relationship between space and time to remain intact. Einstein had a breakthrough, realizing that time itself could change.

Physicist Robbert Dijkgraaf: “Einstein’s deep view was that space and time are basically built up by relationships between things happening.”

While in his streetcar-turn-rocket, his watch would still be ticking, but when he looked back at the tower, the clock would appear to have stopped. The faster he moved through space, the slower he moved through time, a phenomenon he called time dilation.

Time could stretch and contract, varying with extreme movement through space. With this newfound variability, time now deserved its own dimension alongside space, and the concept of space-time was born.

Not only are space and time malleable at the speed of light, an object’s mass can stretch. As an object approaches maximum speed, its mass increases, revealing how energy and mass are interchangeable, an understanding that led Einstein to his famous equation, E=mc2.

By the universe’s standards we are slow as snails, so the variability of mass and energy, and space and time are beyond our typical daily experiences, but relativity has huge implications nonetheless.

Time runs slower on the earth’s surface than it does above the atmosphere, which is why high-precision GPS satellite systems have to take relativistic differences into consideration. Although the differences are measured in nanoseconds, if left unaltered GPS systems would produce errors in global positions within minutes, causing chaos pretty much everywhere in our modern world.

Timely illusions

Albert Einstein: “People like us, who believe in physics, know that the distinction between past, present, and future is only a stubbornly persistent illusion.”

Wrapping our heads around the idea that time could be relative and illusory is challenging.

We can start with right now, this moment, looking at this word. Now we are only experiencing this word right here, then this word. Our mind weaves these present moments together into a sense of time passing, like words strung together to form a sentence.

As with sentences, the past and the future are mental constructions, with the past being constructed from our memories, and the future with our projections of what a present moment could look like.

The only part of time that ever actually happens is the present moment.

And since there is always a present moment happening, the present is just one long forever.

Ultimately what we conceive of as time passing is a measure of movement, for us the earth’s rotation and orbit around the sun, and the moon’s orbit around the earth. As with defining energy or any physical phenomenon, we are talking about the same thing over and over again: movement through space. We even see it in the language we use to describe time, as “flowing” or “flying” or “standing still.”

If our notion of time is based on a particular kind of movement through space, then other types of movements could produce different experiences of time, which is why massless particles moving at the universe’s maximum speed are timeless, with light transcending both space and time.

Physicist Stephen Hawking: “Time travel used to be thought of as just science fiction, but Einstein's general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out.”

We could think of the present moment as the frame of a movie, and our sense of time as the collection of frames into a sequence.

Imagine a film editor connecting frames together into particular sequences, and moving them through space with a film projector. How the frames are connected and how they move produces the experience of time flowing in a particular way. From here it’s easier to imagine how frames could be pieced together so that time and space could jump, similar to a dramatic cut from one scene to the next in a movie.

At its most basic, time is a pattern of movement through space, and it’s in our interpretation of these patterns that we perceive changes in time.

A series of frames of a person sitting alone in a room would feel slower than an action scene, which we experience in our daily life, with less eventful days dragging on, and days where we are actively engaged in a whirlwind of events feeling like a blur of fast moving moments.

Overall the sequence of frames that we experience is most characterized by a very particular pattern of movement: entropy.

If we drop an egg and it breaks, we can’t put the egg back together again. We can affect the future, but not the past, a fundamental asymmetry in how we influence the world around us. The egg’s newfound disordered state is permanently disordered, and the arrow of time marches on.

Physicist Sean M. Carroll: “The fact that you can remember yesterday but not tomorrow is because of entropy. The fact that you're always born young and then you grow older, and not the other way around like Benjamin Button - it's all because of entropy. So I think that entropy is underappreciated as something that has a crucial role in how we go through life.”

Entropy is one of the only measurements in physics that requires a particular direction of time. Physical laws in general have time symmetry, meaning that if the direction of time were flipped, an event would play out the same way.

An example would be the effect of gravity on a ball. A video of a ball being tossed up, slowing to a stop, then falling would be the same whether played forwards or backwards, although everything that we experience after the effect of gravity no longer has time symmetry. As kinetic energy is dissipated and entropy is increased, the ball bounces less and less until it eventually comes to a stop.

Why is entropy different from other physical laws?

One theory is that the arrow of time is a result of our relative proximity to the uniqueness of the Big Bang, a special event that broke the symmetry of time.

We can think of entropy as a movement towards complexity, from the low entropy state of the unbroken egg, with fewer possible forms, to the high entropy state of the broken egg, where there’s an increase in possible arrangements. It’s as if the Big Bang set up the special circumstances needed to have a universe of growing complexity.

Although entropy is fundamental to our universe as a whole and to how we experience the world around us, it is an emergent property of matter, a gradual decline into disorder that we see at a molecular level, and is ultimately a description of molecular motion.

At a subatomic scale there is no distinguishable arrow of time, rather we find identical knowledge of the past and the future, with an array of possible outcomes. While at a human and cosmic scale we see an irreversible growth of entropy, at a subatomic level motion is reversible.

Physicist Stephen Hawking: “Quantum physics tells us that… the (unobserved) past, like the future, is indefinite and exists only as a spectrum of possibilities.”

Despite these fundamental differences in motion, from a cosmic scale all the way down to the subatomic level we see how time (or timelessness) is related to particular kinds of movements through space.

It’s no wonder that our sense of time can be altered by motion or places, from the experience of time slowing down while sitting in traffic to a feeling of déjà vu when we enter a particular place.

If we think about it, our perception of time colors pretty much everything about our life, and is continually changing. We all remember how long a year felt when we were young, when summers seemed to go on forever.

When we were four, one year was a quarter of our life, a huge portion of everything that we had experienced so far, while at 40, one year is merely 1/40th of what we have experienced. Our sense of time speeds up, as each succeeding year is a smaller and smaller percentage of our life, showing us yet again how time is a matter of perspective.

In the novel Einstein’s Dreams, physicist Alan Lightman imagines 30 otherworldly places where time behaves differently, dreamt up by a fictional version of Einstein while he was working on his theory of relativity in 1905:

“Suppose time is a circle, bending back on itself. The world repeats itself, precisely, endlessly. For the most part, people do not know they will live their lives over. Traders do not know that they will make the same bargain again. Politicians do not know they will shout from the same lectern an infinite number of times in the cycle of time. Parents treasure the first laugh from their child as if they will not hear it again.”

Einstein’s Dreams made the strangeness of modern physics more intelligible by imagining the implications of it being any other way:

“A person who cannot imagine the future is a person who cannot contemplate the results of his actions.”

Why do we experience a definite arrow of time?

Why entropy, why a continual increase in complexity? We can look to the world of artificial Intelligence to get some clues.

AI Scientist Yann Lecun: “Prediction is the essence of intelligence.”

Through an understanding of cause and effect, our sense of time is crucial to our ability to learn and acquire wisdom. We use past experiences and foreseen outcomes when we make decisions, a process that has been replicated in the development of machine learning.

Any learning, growing, and evolving is part of a unified process over time. Without a sequence of events, we don’t have the references we need in order to learn. A child’s intelligence grows more complex with each sequence of cause and effect, increasing their understanding of the world around them. Over the course of our lives we are shown millions of examples of cause and effect, allowing us to spot patterns and learn, just as AI is doing now.

As we learn and grow we develop a unique sense of self, with time being at the center of it all. We experience fear when we expect a bad outcome, and elation when we expect a good one. In the middle of these extremes are the complex combinations of emotions unique to each of us, which leads us to larger questions about where our sense of self comes from.

Are we emergent from all of this information processing, or is our sense of self something else entirely?

We’ll fall down that fascinating rabbit hole when we explore the nature of our mind. For now, we have discovered that time is our interpretation of various movements through space, as if each of us has a little film editor in our head putting together the movie of our life, transforming a vast collection of present moments into a unique story.

We don’t see the arrow of time at a subatomic level, so we know there’s something special about the presence of linear cause and effect at our human scale, as well as the larger cosmic time scale.

If we compare the universe today to any earlier point in time, we find that entropy has always been rising and continues to rise, giving us our increasingly complex world.

Dark matters

Physicist Lee Smolin: “General relativity predicts that time ends inside black holes because the gravitational collapse squeezes matter to infinite density.”

Wherever we look in modern physics, questions of gravity are lurking, the mysterious force that keeps us from falling off the planet, the weakest yet most pervasive of all the forces, which as it turns out, isn’t really a force at all.

In 1687 Newton’s universal law of gravitation got us started, giving us a practical understanding of what we experience as gravity.

It states that two masses exert gravity on each other over a distance. The bigger the mass, the more gravity between them. Newton’s laws don’t explain what gravity is exactly, only its effects and how those effects are related to the mass of an object.

This is where we get back to Einstein. In 1915, ten years after developing his first theory of relativity, now called special relativity, Einstein completed a follow up investigation, which is essentially a theory of gravity.

His original theory of relativity had focused on special cases, with movements in a straight line at a constant speed, namely light. For other situations and movements, he needed to account for gravitational pull.

Instead of gravity being an invisible force that attracts objects together, Einstein showed how gravity is a result of the curving or warping of space itself, once again connecting together what had seemed like two separate phenomena: the effect of gravity and the geometry of space.

A moving object will look as if a gravitational force is being exerted on it, although it is simply following the shortest path along the curved fabric of space-time.

The more massive an object, the more the object warps the space around it, and it’s the change in space that produces the effect of gravity.

Physicist Alan Guth: “In the context of general relativity, space almost is a substance. It can bend and twist and stretch, and probably the best way to think about space is to just kind of imagine a big piece of rubber that you can pull and twist and bend.”

Large objects such as earth curve the fabric of space-time around them, resulting in smaller objects being pulled closer. We are pinned to the ground because space, being so distorted by the earth’s mass, pushes us down from above.

As we discovered with light and matter, gravity isn’t just a single phenomenon. It is theorized to exist as a kind of particle force, mediating gravitational interactions at a subatomic level (although gravitons have yet to be detected), while also existing as a wave at a cosmic scale.

Every phenomenon we experience can behave like something else, making attempts to fully distinguish them next to impossible.

Einstein predicted that something special would happen when two very large masses, such as planets or stars, orbit around each other, proposing that these kinds of movements could cause ripples in the fabric of space-time, spreading out like ripples from a rock thrown into a pond. These gravitational waves were theorized to travel at the speed of light, squeezing and stretching anything in their path as they move through space.

In 2015, scientists discovered gravitational waves for the first time, proving Einstein right once again. The waves detected were created when two black holes crashed into one another 1.3 billion years ago, eventually finding their way to us here on earth.

Physicist Subrahmanyan Chandrasekhar: “The black holes of nature are the most perfect macroscopic objects there are in the universe: the only elements in their construction are our concepts of space and time.”

Enter the Kugelblitz. Light is affected by gravity, making it act like it has mass, an effect that allows light to create more gravity, which in turn affects light again, a process that can feed on itself until light (at least theoretically) turns into a black hole called a Kugelblitz, or “ball of light,” that swallows everything in sight and makes time stand still.

What this means is that gravity can create the effect of a mass without a mass ever existing, a massive ball made entirely out of massless things.

Space-time can be curved by energy, momentum, pressure, and stress, not just mass, with matter once again vanishing from the picture.

No wonder we have discovered only 5% of the universe, with 27% estimated to be dark matter (mysterious stuff affecting the shape and interaction of visible matter), and 68% dark energy (what is out there because of how the universe is expanding). The presence of gravity has given us some general clues, but what exactly the universe is made out of remains a mystery.

Physicist Barry Barish: “Everything we know about the universe is studied by using telescopes or other instruments that look at visible light, infrared, ultraviolet or X-ray - different wavelengths of electromagnetic interactions. Only 4 percent of what's in the universe gives off electromagnetic radiation, so we don't have any handle on the rest.”

In 2019 physicist Melvin Vopson proposed a theory that accounts for all the universe’s undetected mass, called mass-energy-information equivalence, arguing that information itself is a fundamental building block of the universe.

Information would be its own state of matter that has mass, meaning your full hard drive would be marginally heavier than an empty one, and the mass of that information could be converted into energy.

Physicist Wolfgang Pauli: “The best that most of us can hope to achieve in physics is simply to misunderstand at a deeper level.”

Not only is a tiny portion of the universe currently perceivable to us, the quantum world remains outside of the realm of our everyday experiences, leading scientists to ponder whether or not the true nature of reality is knowable through our perceptions.

If a tree falls…

Physicist Frijitov Capra: "In atomic physics, we can never speak about nature without, at the same time, speaking about ourselves.”

We come across fundamental questions about our role as observers when we zoom into the behavior of particles, reminiscent of the age-old question of whether or not a tree falling in the forest makes a sound if there’s no one around to hear it.

Superposition, a quantum particle's ability to exist in multiple possible states, defies classical physics, since all of these possibilities exist simultaneously until an observation is made.

This brings us back to our electronic dart board analogy, where the empty board is like the frozen state of particles in superposition. Until there’s some kind of interaction, the dart board remains empty, with all of the possible locations where darts could land open and available. After an interaction occurs, the array of possibilities becomes a material reality, with the darts now in particular places on the board.

Defining an interaction can be tricky, with some physicists arguing that any particle interaction is enough to affect how particle behavior plays out, but what we do know is that how we set up an experiment impacts the outcome, so the act of observation is playing a role.

In the famous double-slit experiment, a laser beam is pointed at a plate with two slits in front of a screen. If the particle detector is focused on the screen, it records the wave nature of light, with photons passing through both slits simultaneously, creating an interference pattern on the screen.

Light behaving like a particle (left) and the wave nature of light (right)

But if the particle detector is focused on the slits, photons are observed as points of light that pass through a single slit. When we get down to a subatomic level what we observe changes depending on how we observe it.

We don’t ever experience the frozen state of superposition, so it’s hard to imagine what an existential ambiguity like this could even look like, which brings us to the fate of Schrödinger's cat.

Schrödinger's cat is a thought experiment that illustrates the paradox of superposition. A hypothetical cat in a box is considered to be simultaneously alive and dead as a result of its fate being linked to a radioactive subatomic event that may or may not occur. Since subatomic particles don’t have the kind of fixed properties that we observe at the scale of the cat, until we open the box to see the cat’s fate, it’s in an existential limbo.

So if no one is around does the falling tree make a sound?

Let’s start with our human scale. If by sound we mean the physical disturbances caused by the falling tree, resulting in audio frequencies traveling through the air, we could comfortably think to ourselves, well yes, of course it makes a sound.

But the human experience of sound, vibrating nerve endings in our ears that send electrical signals to the parts of our brain responsible for the perception of sound, well that is an interpretation of reality that requires a human body.

At a subatomic scale the ambiguity goes a step further, suggesting that the tree itself wouldn't exist without some kind of interaction.

This is where we get back to what constitutes an observer. We could think of our shared reality as one big conference call where observers are always on the line. But that would also imply that if for some reason everyone got off at once, the call would end, effectively ending existence itself.

Since the universe is built out of a constant flow of interactions, we can get some solace that the tree is still around when we aren’t looking, but the larger question of how our perceptions affect the construction of our reality remains.

Astrophysicist Neil deGrasse Tyson: “In modern times, if the sole measure of what’s out there flows from your five senses then a precarious life awaits you.”

Our perceptions can be misleading and result in misguided assumptions about the world around us. Humans once thought the world was flat, only to learn that our everyday experience of walking around a flat place doesn’t reflect the actual shape of the world.

We rely on our senses to give us a full understanding of our surroundings, but what if our perceptions do nothing more than tell us about our perceptions?

Can we expect our senses to be able to tell us anything deeper about reality?

Whether we are simply going about our life or conducting a scientific experiment, we are recounting the world as we experience it with our senses, especially sight and touch, which through history has resulted in a reality described as objects in relationship to other objects, with absolutely no insight into what happens under the hood at a quantum level, or at a cosmic scale.

Scientific discovery since the 16th century has propelled us into the previously unknown with the microscope, the telescope, fMRI machines, and hadron colliders, but in the end we are still humans using our senses to describe the world as we perceive it.

The quantum world is abstract and counterintuitive, with particle behavior that exists outside of our everyday experience of continuous movement and definite locations in space. When we zoom into matter it’s as if our experience of space-time no longer exists at that scale.

Physicist David Bohm: “In relativity, movement is continuous, causally determinate and well defined, while in quantum mechanics it is discontinuous, not causally determinate and not well defined.”

Physicists have a lot of ways of interpreting what is happening with the lack of fixed properties at a quantum level, but no interpretation has been proven or disproven by experiment yet.

Some physicists argue that quantum mechanics is just a mathematical model that makes accurate predictions, and that it doesn’t say anything about the nature of reality, concluding: “Shut up and calculate.”

While others argue that the strangeness of superposition can give us insights into the world around us. Since our reality is built out of a constant flow of interactions (try getting through a day without one), it’s these unique interactions at the quantum level that give rise to the physical world.

In this view quantum uncertainty isn’t just an abstract concept, but is a real part of our everyday world, with everything we experience emerging quite literally from these interactions.

This is where we get back to the falling tree. If something didn’t have any interactions, it wouldn’t exist in any meaningful sense anyway.

Physicist John Wheeler: “To describe what has happened, one has to cross out that old word ‘observer’ and put in its place the new word ‘participator.’ In some strange sense the universe is a participatory universe.”

Subatomic particles exist outside of the limitations of space and time. Space-time also breaks down to the point of irrelevance in situations with extreme gravity, as with black holes, leading some scientists to declare that “space-time is doomed,” and that something else entirely is more fundamental to our reality.

Space-time is doomed

Albert Einstein: “The most important tool of the theoretical physicist is his wastebasket.”

At the turn of the 20th century, classical physics had to be transformed with the discovery of quantum mechanics and the principles of space-time, as physicists realized that there were clues of different realities hidden in plain sight. This same kind of transformation is happening again, 100 years later.

Mathematical Physicist Edward Witten: “I don't think that any physicist would have been clever enough to have invented string theory on purpose… Luckily, it was invented by accident.”

Most of us have heard about string theory, at least in passing, which theorizes that space-time emerges from more primitive building blocks that are without space, time, or gravity.

These building blocks would not be point-like particles, but rather one-dimensional objects called strings, tiny loops of energy that vibrate at specific frequencies, giving rise to various types of particles depending on their specific vibrational patterns. Different particles could be thought of as the same string playing different notes, and it’s in the variety of possible notes that would account for everything that we observe in our universe.

Space-time and the effects of gravity would emerge from theses fundamental interactions, theorized to occur on the far walls of the universe, creating the illusion of space, time, and gravity in its interior, all of it emerging as a kind of timeless hologram.

And this is where we get back to the issue of time. The universe we live in is not like a timeless box, but one that has a moment of creation and is expanding at an accelerating rate.

Physicist Louis de Broglie: “The actual state of our knowledge is always provisional and... there must be, beyond what is actually known, immense new regions to discover.”

Another place to start in unifying the contradictions and complexities of modern physics is by deciphering the uncertainties that underlie quantum mechanics.

Probability densities of hydrogen atom electrons, revealing mysterious underlying geometries

When physicists are calculating the probabilities of particles taking one path over another, they add up all the possible paths in an effort to predict the final state, or future, of a particular particle. Physicists can’t get an exact future, but these complex calculations do a good job of predicting possible outcomes.

A few decades ago scientists stumbled upon a mathematical term that could collapse all of these complex calculations into a single formula, a simple solution lurking in plain sight.

New and unique collaborations started between physicists and mathematicians, who began pursuing hidden mathematical structures that could underpin our physical reality.

Physicist Leonard Susskind: “There is a philosophy that says that if something is unobservable… it is not part of science... By that standard, most of the universe has no scientific reality - it's just a figment of our imaginations.”

All of these explorations are emerging from obscure areas of mathematics that were typically disconnected from the world of physics, with enigmatic names like combinatorics and number theory, which are beginning to show how higher-dimensional mathematical views can describe what’s happening in our lower-dimensional world.

The amplituhedron, a higher-dimensional geometry that could underpin space-time

Particle interactions that physicists would traditionally describe with 30 pages of algebra are instead being represented with deceptively simple geometries, allowing physicists to combine these shapes together into the building blocks of our complex natural world.

Physicist Nima Arkani-Hamed: “nature has very few good ideas — it recycles them in subtle and interesting ways, over and over again — and it's our job to understand how that works.”

None of this is like the geometry we learn in school, where the points represent actual locations in space. Instead these building blocks are the result of a world of ideas, with particles that actually exist being described by nonphysical geometries. It’s as if scientists have discovered the universe's architectural plans, a kind of geometric kit of parts.

All of this delves fully into the bizarre, implying that what exists under the hood of our reality isn’t real stuff, but rather a kind of logical process.

In order to comprehend what is going on we have to leave our common sense behind, and imagine a reality beyond our physical world, one of logic and mind-like processes.

After all, everything we see in the world around us arises from the mind, houses, cars, computers, jobs, marriages, friends, all of it first originated from our thoughts. Without thoughts could we even exist in any meaningful way? All of this points back to the famous "first principle" of philosopher René Descartes: “I think, therefore I am.”

Physicist Erwin Schrödinger: “Consciousness cannot be accounted for in physical terms. For consciousness is absolutely fundamental. It cannot be accounted for in terms of anything else.”