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 ====== 1. Particle Age ======
-SOCRATES: The Brahmaputra originates on the northern slopes of the Himalayas from some glaciers like Chemayungdung and Angsi, which are only 71 km east of Manas Sarovar. Many rivers emerge from these glaciers and merge into one stream to form the Tsangpo River. As difficult as it is to find the source of a river, it is at least 24 times more difficult to find the source of the universe.
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+    <title>Particle Age Table</title>
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+<body>
-Rabi: I understand that you want to focus only on Angsi to make things easier. But simplifying the description of the particle age of the universe will not be so straightforward. This cannot be understood without understanding the standard model of particle physics mathematically.
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-SOCRATES: The ancient Indians said that Brahma is the foundation of the universe, Manas Sarovar is created from the mind of Brahma, and Brahmaputra is the son of Brahma. Since Juno could not understand the mind of Brahma after so many visits to Manas Sarovar, I don't think we can understand the mathematical form of the Standard Model, no matter how much we talk to you.
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-Juno: With that out of the way, everyone, let's go to the supposed source of the Brahmaputra. Sitting on the ice and talking will hopefully reduce Rabi's fire a bit.
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-Socrates: Where is this 'supposed' source?
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-Hermes: [[https://maps.app.goo.gl/UHzmtQVAnjAieTDb7|Latitude 30.348, Longitude 82.045]], meaning 30 degrees north of the equator, and 82 degrees east of the prime meridian passing through Greenwich, England. It should be remembered that the distance from the equator to the north pole above is 90 degrees, and if you go around the whole earth along the equator from the prime meridian and return to Greenwich, a total distance of 360 degrees is covered. So 30 degrees is one-third of ninety degrees, and eighty-two degrees is about one-fourth of 360 degrees.
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-[Everyone flies to the source of the Angsi River while listening to Hermes' useless speech. Sitting on the ice on the banks of Angsi, everyone listens to Rabi about the particle age.]
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-===== - Spacetime from the Big Bang =====
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-SOCRATES: The big bang theory, the standard model of cosmology, says that our universe, meaning all of us, came from an almost infinitely small point. Do you remember the comedy of Borges with two point-dwellers? From a point about fourteen billion years ago, spacetime began to expand, an event called the Big Bang. This expansion is still going on due to the explosive energy of the Big Bang, our universe is still getting bigger day by day. But when I go to tell this to the gods of Olympus, they ask, what was before this big bang or how did this big bang happen? If the gods ask such questions, what will happen to mortals?
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-Rabi: If spacetime was born at the time of the Big Bang, then the question of what was before, or beyond, the Big Bang is meaningless. But the question is, can there really be no spacetime except our spacetime created from the Big Bang? Could it even be that nature is actually a multiverse with many or an infinite number of four-dimensional universes? Is there nothing beyond the four dimensions we are thinking of with three dimensions of space and one dimension of time? Could our four dimensions be born from another world of higher dimensions? We still don't know the answer to these, many mathematical theories have been made as an attempt to know, but which theory or model is correct has not yet been proven through observation. It is very common to use many dimensions in string theory.
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-SOCRATES: I understand that we know what happened after the Big Bang, but the cause or mathematical basis of the Big Bang itself is still unknown. Are mathematical theorems part of the universe, or laws imposed on the universe from outside?
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-Rabi: Good question. The debate started by your student Plato and his student Aristotle is still going on. This figure made by Roger Penrose can explain the matter. Three worlds can be imagined in nature or reality: mathematical, physical, mental. There are countless things in the mathematical world (everything in mathematics), but only a few of them (eg, the fundamental theories of physics) make up, or govern, the entire physical world, shown by the arrow marked '1' in the figure. Similarly, there are countless things in the physical world (from gorillas to galaxies), a few of which (eg, our brains) make up, or control, the entire mental world, shown by '2'. And there are countless things in the mental world (all the thoughts of all beings), only a few of which (some thoughts of theorists) can contain the mathematical world, shown by '3'. Now the question is which world is the first in this cycle, from which world the other two worlds were born or started, or do all three exist together? According to Plato everything starts from the mathematical or formal world, according to Aristotle the physical world first, and according to Bishop Berkeley everything is born from the mental world.
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-SOCRATES: That means Plato thought that all theories would exist even if there were no universe, because theories exist outside the universe in a separate mathematical world.
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-Rabi: Yes. And according to Aristotle, theory is a human-made model to explain various phenomena of the universe. If there is no universe, there will be no theory.
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-SOCRATES: But Aristotle's materialism seems the most correct for our universe.
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-Rabi: That is your own choice. I am a Platonist. One who understands the meaning of the beauty and theory of Math cannot think of anything other than Math as the source.
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-Socrates: Well, then these three worlds together what can be said to be the basic structural elements of reality?
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-Rabi: Definitely STEMIC, meaning space, time, energy, matter, information, and consciousness.
+    <div class="timeline-table">
+        <!-- Row 1 -->
+        <div class="t-row">
+            <div class="t-header" onclick="toggleRow(this)">
+                <div class="col-time">0</div>
+                <div class="col-title">The Big Bang</div>
+                <div class="col-toggle">
+                    <svg viewBox="0 0 24 24"><polyline points="6 9 12 15 18 9"></polyline></svg>
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+            <div class="t-content">
+                <div class="t-content-inner">
+                    The saga of our cosmos began at "time zero" with the Big Bang—a singular, monumental event that marked the simultaneous origin of space, time, energy, and matter (STEM). Emerging from a state of unimaginable and infinite density, the universe was not a traditional explosion of matter bursting out into a pre-existing, empty void. Rather, it was a sudden, violent eruption and rapid expansion of space itself. This "primeval fireball" was so incredibly hot, dense, and energetic that the standard laws of physics we rely on today simply did not yet exist. In this initial instant, the entire observable universe was compressed into an infinitesimally small point, possessing infinite temperature and pressure. This foundational singularity set into motion the relentless expansion and complex evolutionary trajectory of the cosmos, establishing the ultimate starting point for the 14-billion-year history of everything that currently exists.
+                </div>
+            </div>
+        </div>
-Socrates: Where is your math?
+        <!-- Row 2 -->
+        <div class="t-row">
+            <div class="t-header" onclick="toggleRow(this)">
+                <div class="col-time">10<sup>-35</sup> to 10<sup>-32</sup> seconds</div>
+                <div class="col-title">Cosmic Inflation</div>
+                <div class="col-toggle">
+                    <svg viewBox="0 0 24 24"><polyline points="6 9 12 15 18 9"></polyline></svg>
+                </div>
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+            <div class="t-content">
+                <div class="t-content-inner">
+                    Almost instantly following the initial singularity, in the fleeting blink of an eye between 10<sup>-35</sup> and 10<sup>-32</sup> seconds, the infant universe experienced a period of breathtaking, exponential growth known as Cosmic Inflation. During this infinitesimally brief moment, the very fabric of space stretched by a staggering factor of roughly 10<sup>50</sup>, causing the universe to swell from a subatomic scale to macroscopic proportions at speeds far exceeding the speed of light. This rapid, dramatic transformation was absolutely vital for the future structural integrity of the cosmos. By expanding so violently, inflation effectively ironed out and smoothed the extreme early chaos and initial quantum irregularities. It ensured that energy and matter were distributed evenly and uniformly across vast distances, laying the essential, balanced groundwork necessary to eventually allow for a stable, highly organized universe rather than a hopelessly chaotic one.
+                </div>
+            </div>
+        </div>
-Rabi: Everything in math is inside that information.
+        <!-- Row 3 -->
+        <div class="t-row">
+            <div class="t-header" onclick="toggleRow(this)">
+                <div class="col-time">10<sup>-43</sup> to 10<sup>-10</sup> seconds</div>
+                <div class="col-title">Separation of Forces</div>
+                <div class="col-toggle">
+                    <svg viewBox="0 0 24 24"><polyline points="6 9 12 15 18 9"></polyline></svg>
+                </div>
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+            <div class="t-content">
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+                    As the intense, unfathomable heat of the universe's absolute beginning began to gradually fade within the first microscopic fractions of a second, the fundamental rules of nature started to take definitive shape through the Separation of Forces. Initially, under extreme temperatures, all of nature’s energy and interactions were perfectly bound together in a single, unified "superforce." However, as the universe rapidly expanded and the temperature systematically dropped, this primordial unity shattered in a series of phase transitions. The forces began to "freeze out" and act completely independently. Gravity was the first force to break away and separate from the others, establishing the rules of mass and attraction. This was sequentially followed by the decoupling of the strong nuclear force, the weak nuclear force, and finally electromagnetism. This critical separation established the distinct physical interactions and diverse energetic rules that govern the complex behavior of the world around us today.
+                </div>
+            </div>
+        </div>
-SOCRATES: What was the need to separate consciousness? Everything mental is information.
+        <!-- Row 4 -->
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+                <div class="col-time">10<sup>-35</sup> to 1 second</div>
+                <div class="col-title">Particle Creation & Annihilation</div>
+                <div class="col-toggle">
+                    <svg viewBox="0 0 24 24"><polyline points="6 9 12 15 18 9"></polyline></svg>
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+            <div class="t-content">
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+                    During the turbulent first full second of existence, the incredibly hot universe functioned as a colossal, high-energy furnace where pure radiant energy was constantly transforming into physical substance. In this dynamic era of Particle Creation and Annihilation, energy was directly converted into the very first basic building blocks of matter, such as quarks and leptons (including electrons), via a process known as "pair production." As these elementary particles rapidly emerged, matter and its counterpart, antimatter, engaged in a violent, continuous cosmic struggle, colliding and instantaneously destroying one another upon contact to release bursts of energy. Fortunately for the future cosmos, this annihilation was not perfectly symmetrical. A tiny, miraculous imbalance existed, leaving a slight but immensely consequential excess of ordinary matter surviving the conflict. This small, surviving remnant of particles became the foundational raw material eventually used to build every star, planet, galaxy, and living being in existence.
+                </div>
+            </div>
+        </div>
-Rabi: Many cognitive scientists think that consciousness is another type of thing, not information. But that is another debate. We should first focus on just the 'STEM' of STEMIC, meaning space, time, energy and matter.
+        <!-- Row 5 -->
+        <div class="t-row">
+            <div class="t-header" onclick="toggleRow(this)">
+                <div class="col-time">3 minutes to 15 minutes</div>
+                <div class="col-title">Primordial Nucleosynthesis</div>
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+            <div class="t-content">
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+                    By the time the universe was exactly three minutes old, it entered a crucial, transformative phase of "cosmic cooking" scientifically termed Primordial Nucleosynthesis. This vital process was initially held back by a physical "bottleneck," as the environment remained too intensely hot and energetic for simple atoms to bind and hold together without instantly being blasted apart. However, once the ambient temperature successfully dipped below one billion degrees Kelvin, protons and neutrons could finally fuse and remain stable. This brief "Nuclear Epoch" produced the very first atomic nuclei in the universe, primarily forming heavy hydrogen (deuterium), large quantities of stable helium, and trace amounts of lithium. This grand atomic assembly line was extraordinarily brief, lasting only about fifteen minutes before the universe expanded and cooled too much to create anything heavier. It left behind a permanent chemical signature of roughly 75% hydrogen and 25% helium—a primordial ratio that we still observe in the oldest stars today.
+                </div>
+            </div>
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-SOCRATES: These four together can be explained by relativity, but only on a much larger scale. Relativity does not apply at very small atomic or subatomic scales, where energy and matter have to be explained by quantum theory. If a theory can be made combining general relativity with quantum theory, it is possible to explain STEM at all scales together. Many physicists are still trying to make a Theory of Everything (TOE), aren't you one of them?
+        <!-- Row 6 -->
+        <div class="t-row">
+            <div class="t-header" onclick="toggleRow(this)">
+                <div class="col-time">50,000 years</div>
+                <div class="col-title">Matter Domination</div>
+                <div class="col-toggle">
+                    <svg viewBox="0 0 24 24"><polyline points="6 9 12 15 18 9"></polyline></svg>
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+            <div class="t-content">
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+                    Following the initial frenzy of particle creation and rapid nuclear fusion, the cosmos continued to expand in total, featureless darkness for many thousands of years until it reached a profound, pivotal turning point known as Matter Domination. At this critical stage, occurring roughly 50,000 years after the Big Bang, the universe experienced a fundamental "crossover point." Because the expansion of space diluted the energy of radiation much faster than the density of matter, the energy density of physical matter finally exceeded and overpowered that of radiation. This fundamental shift marked the definitive end of the early "Radiation Era" and the beginning of the "Matter Era." It was a defining moment in cosmic history because it allowed the persistent, slow influence of gravity to finally begin pulling matter together. This subtle clumping initiated the formation of the first large-scale structures, creating the vast, invisible dark-matter scaffolding upon which all future galaxies would eventually grow.
+                </div>
+            </div>
+        </div>
-Rabi: I still think some future version of string theory will unify everything. But surely you will not understand that. Rather, we should now see what it means to unify, and what is this 'everything' in TOE?
+        <!-- Row 7 -->
+        <div class="t-row">
+            <div class="t-header" onclick="toggleRow(this)">
+                <div class="col-time">300,000 to 380,000 years</div>
+                <div class="col-title">Recombination & Decoupling</div>
+                <div class="col-toggle">
+                    <svg viewBox="0 0 24 24"><polyline points="6 9 12 15 18 9"></polyline></svg>
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+            <div class="t-content">
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+                    Finally, in a momentous epoch spanning between 300,000 and 380,000 years after the Big Bang, the expanding universe cooled sufficiently for slow-moving electrons to be successfully captured by atomic nuclei, settling into stable orbits. This critical event, scientifically known as Recombination, formed the very first neutral atoms of hydrogen and helium. Previously, the universe had been a dense, opaque plasma where free-roaming electrons continuously scattered light, trapping photons in a thick, electrically charged fog. By sweeping up these free electrons to form neutral atoms, the universe was suddenly neutralized. This allowed photons to completely decouple from matter and travel freely across the vastness of space without interference. For the very first time, the universe became entirely transparent. Today, we can still detect these ancient, newly freed photons as the Cosmic Microwave Background (CMB)—a faint, stretched, fossilized afterglow that serves as the ultimate, direct "baby picture" of our newborn universe.
+                </div>
+            </div>
+        </div>
-SOCRATES: Then tell us what is meant by Everything, and what is meant by unifying.
+    </div>
-===== - Birth of Energy =====
+    <script>
-Rabi: Currently there are four types of energy in our universe. Each energy interacts differently. The interaction of energy is called a force. Then there are also four forces associated with the four energies: strong, electromagnetic, weak, and gravitational forces.
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-SOCRATES: Yes, it appears so in this figure of yours. But why do you start with energy, leaving space, time, matter of STEM?
-Rabi: Because, Socrates, after the Big Bang there was only spacetime and energy in the beginning, matter was then created from energy; It can be explained by Einstein's $E=mc^2$, if $E$ means energy and $m$ means matter, $c$ is the speed of light. We'll get to the matter later. As seen in the figure, four types of energy or force have come into existence independently within the first 1 picosecond of the universe's history. A picosecond is one trillionth of a second.
-SOCRATES: Matter doesn't matter even if we don't understand it now, but how will spacetime be born without telling it to energy?
-Rabi: We cannot explain something called zero time. At Planck time, all our theories fall apart. Planck time is 1 quattuordecillionth of a second (45 zeros before one), that is $10^{-45}$ seconds. Since Planck's time there has been spacetime, and with it only one unified energy and force. It's called the TOE force, because if a theory of everything is ever discovered, that theory can explain this force.
-Rhea: Wait, I don't understand the time and temperature thing in your figure. Accustomed to the cultural age, I have a hard time digesting such a small number. What was the age and temperature of the universe at the time of this tow force?
-Rabi: Remember, all forces are born in the first picosecond. The TOE force existed much earlier, when the universe was less than 10 trdecillionth of a second. If you go to the [[un:number|number]] article you will get a list of names of small and large numbers. Meditating on this list from time to time will allow you to experience such numbers.
-Rhea: From what I see in the list, 1 tredecillion means 42 zeros after one, then 10 tredecillion means 43 zeros after one. Just twelve zeros after one makes one trillion, and here we have to put 43. It is impossible for any human being to feel the terrible shortness of time when one second is divided by such a large number. And I don't even want to try to feel the temperature.
-Rabi: It's cool to sit in this ice and wonder what the temperature of the universe was at that time. Think about it. The source of the Brahmaputra is very cold, the temperature increases as you go towards the estuary (Bay of Bengal). The opposite is true of the universe. The temperature was the highest during the Big Bang, and since then, as the universe has expanded, both its density and temperature have decreased, and are still decreasing.
-Rhea: If we look at this figure and the list of numbers, we can say that when the age of the universe is 10 tredecillionths of a second ($10^{-43}$ seconds), and when the temperature is 100 nonillion Kelvin ($10^{32}$ K), then by breaking the TOE force, two separate forces were born, gravity and GUT force. What does 'GUT' mean?
-Rabi: 'GUT' stands for Grand Unified Theory. Abdus Salam, a scientist exiled from Pakistan for belonging to the Ahmadiyya community, received the Nobel Prize for the discovery of this theory, along with Glashow and Weinberg. This is the closest theory to TOE that has been proven so far. When the age of the universe is 100 decillionths of a second, and the temperature is 1 octillion degrees, two independent forces arise from the gut force: the strong nuclear force and the 'electroweak' force. And finally, at a picosecond age, at a temperature of one quadrillion degrees, the electroweak force breaks down to form the last two independent forces: the electromagnetic force and the weak nuclear force.
-Rhea: On the left side of the name of the four forces, I see the names of some particles, and on the right side some numbers and pictures. What does this mean?
-Rabi: This is a basic introduction to these four forces for the benefit of those who may not understand anything through math. Every force works by exchanging certain particles. The particles of the strong force or interaction are the gluons, the photons for the electromagnetic force, and the $W^+$, $W^-$ and $Z$ bosons for the weak force. No such particle has been found for gravity so far, but just as people decide on a name before having a baby, scientists have decided on the name 'graviton' in the hope of future discoveries. The strong force is the strongest, with a strength of 1, and the rest are compared with this using the numbers on the right side of the figure. The electromagnetic force is 100 times weaker than the strong force, the weak force is 1 million times weaker, and gravity is 1 duodecillion times weaker.
-Rhea: But the most important thing is to understand what the forces really are.
-Rabi: That is shown in the four pictures on the far right. Strong and weak forces act only inside the nucleus of an atom. The strong force binds three quarks together to form a proton. The weak force can convert an up quark of this proton into a down quark by converting the proton into a neutron, thus giving rise to radioactivity. Electromagnetic forces hold atoms together by creating an attraction between electrons and protons. And gravity bends the space around the earth and forces the moon to revolve around it.
-Rhea: But you didn't explain one thing. At one picosecond in the middle of your figure it says 'electroweak symmetry broken', what does that mean?
-Rabi: That is the most important thing. I mentioned the sequence of birth of the four energies or forces, but did not explain why it broke from one into four in this way. The reason is called symmetry breaking in physics. A theory in physics that has symmetry means that the theory applies equally in all space and time. The theory of gravity is as true for the apple tree as it is for the Andromeda galaxy, and is as true today as it was yesterday. There is a more extreme form of this symmetry, where even the identity of the particles becomes symmetric, meaning that there is no theoretical difference between one particle and another. For example, there was no difference between photons and Z bosons before the electroweak theory's symmetry was broken. Similar symmetry-breaking has occurred twice before, although they are yet to be detected in lab experiments.
-Rhea: I see, but don't you think, Socrates, that Rabi's explanation here is too much theoretical, and we can't visualize the whole thing yet?
-SOCRATES: Right.
-===== - Birth of Matter =====
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-===== - Background of Photons =====
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-===== - Light, Color, Telescope =====
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