|“||Earth isn't the Human Realm, it's a part of it. A very small dot in between an indefinite amount of planets. There are thousands and millions and billions of other planets and lifeforms out there waiting to be discovered and explored. I don't know who will do it but it'll definitely not me. I already have my handful of annoyance on Earth alone, thank you very much.||„|
|— Carl Black.|
The Human Realm is one of the first realms to ever exist, lasting for nearly 14 billion years, and as far as most are concerned, the realm should continue to exist for billions of years more.
What was there before the creation of the universe is and perhaps always will be a mystery to both humanity and most angels. All that is known is that before there was light, a terrible war was waged for the domination of the universe between God and the Arcuthas against the Abyssal Gods. God was the ruler of light, good and order, and gathered in itself all that was good, all that was fair and luminous.
The Big Bang
After the War of Creation, God created the singularity, and in that singularity, within a moment or so, exploded. After that moment, all distances throughout the universe began to increase from zero because the it changed over time, affecting distances between all non-bound objects everywhere. For this reason it is said that the Big Bang "happened everywhere".
The very early universe
Distances between objects in space have been increasing at all times since the moment of the Big Bang, and are still increasing (with the exception of gravitationally bound objects such as galaxies and most clusters, once the rate of expansion had greatly slowed). During inflation, the expansion accelerated. After inflation, and for about 9.8 billion years, the expansion was much slower and became slower yet over time (although it never reversed). About 3 billion years later, it began slightly speeding up again.
During this epoch, the temperature and average energies within the universe were so high that everyday subatomic particles could not form, and even the four fundamental forces that shape the universe — gravitation, electromagnetism, the weak nuclear force, and the strong nuclear force — were combined and formed one fundamental force.
Grand unification epoch
As the universe expanded and cooled, it crossed transition temperatures at which forces separated from each other. These phase transitions can be visualized as similar to condensation and freezing phase transitions of ordinary matter. At certain temperatures/energies, water molecules change their behavior and structure, and they will behave completely differently. Like steam turning to water, the fields which define our universe's fundamental forces and particles also completely change their behaviors and structures when the temperature/energy falls below a certain point. This is not apparent in everyday life, because it only happens at far higher temperatures than we usually see in our present universe.
The grand unification epoch began with a phase transitions of this kind, when gravitation separated from the universal combined gauge force. This caused two forces to now exist: gravity, and an electro-strong interaction. The grand unification epoch ended with a second phase transition, as the electro-strong interaction in turn separated, and began to manifest as two separate interactions, called the strong and the electroweak interactions.
The electroweak epoch began 10−36 seconds after the Big Bang, when the temperature of the universe was low enough for the electronuclear force to begin to manifest as two separate interactions, the strong and the electroweak interactions.
Inflationary epoch and the rapid expansion of space
At this point of the very early universe, the metric that defines distance within space suddenly and very rapidly changed in scale, leaving the early universe at least 1078 times its previous volume. Although light and objects within spacetime cannot travel faster than the speed of light, in this case it was the metric governing the size and geometry of spacetime itself that changed in scale.
It was triggered by the separation of the strong and electroweak interactions which ended the grand unification epoch. As the inflation field settled into its lowest energy state throughout the universe, it generated an enormous repulsive force that led to a rapid expansion of the metric that defines space itself.
The rapid expansion of space meant that elementary particles remaining from the grand unification epoch were now distributed very thinly across the universe. However, the huge potential energy of the inflation field was released at the end of the inflationary epoch, as the inflaton field decayed into other particles, known as "reheating". This heating effect led to the universe being repopulated with a dense, hot mixture of quarks, anti-quarks and gluons. In other models, reheating is often considered to mark the start of the electroweak epoch, and some theories, such as warm inflation, avoid a reheating phase entirely.
Inflation ended at a temperature corresponding to roughly 10−32 seconds after the Big Bang, but this does not imply that the inflationary era lasted less than 10−32 seconds. After inflation ended, the universe continued to expand, but at a much slower rate. About 4 billion years ago the expansion gradually began to speed up again. The masses of particles and their super partners would then no longer be equal.
Electroweak symmetry breaking
As the universe's temperature continued to fall below 159.5±1.5 GeV, electroweak symmetry breaking happened. So far it was the penultimate symmetry breaking event in the formation of our universe, the final one being chiral symmetry breaking in the quark sector. This had two related effects, the first was that all elementary particles interacting with the Higgs field become massive, having been massless at higher energy levels. The second was the weak nuclear force and electromagnetic force, and their respective bosons (the W and Z bosons and photon) now begin to manifest differently in the present universe. Before electroweak symmetry breaking these bosons were all massless particles and interacted over long distances, but at this point the W and Z bosons abruptly become massive particles only interacting over distances smaller than the size of an atom, while the photon remains massless and remains a long-distance interaction.
After electroweak symmetry breaking, the fundamental interactions have all taken their present forms, and fundamental particles have their expected masses, but the temperature of the universe is still too high to allow the stable formation of many particles we now see in the universe, so there are no protons or neutrons, and therefore no atoms, atomic nuclei, or molecules.
The early universe
After cosmic inflation ends, the universe is filled with a hot quark–gluon plasma, the remains of reheating. From this point onwards the physics of the early universe is much better understood, and the energies involved in the Quark epoch are directly accessible in particle physics experiments and other detectors.
The quark epoch
The quark epoch began approximately 10−12 seconds after the Big Bang. This was the period in the evolution of the early universe immediately after electroweak symmetry breaking, when the fundamental interactions of gravitation, electromagnetism, the strong interaction and the weak interaction had taken their present forms, but the temperature of the universe was still too high to allow quarks to bind together to form hadrons.
During the quark epoch the universe was filled with a dense, hot quark–gluon plasma, containing quarks, leptons and their antiparticles. Collisions between particles were too energetic to allow quarks to combine into mesons or baryons.
The quark epoch ended when the universe was about 10−5 seconds old, when the average energy of particle interactions had fallen below the mass of lightest hadron, the pion.
Baryons are subatomic particles such as protons and neutrons, that are composed of three quarks. It would be expected that both baryons, and particles known as antibaryons would have formed in equal numbers. However, this does not seem to be what happened—as far as we know, the universe was left with far more baryons than antibaryons. In fact, almost no antibaryons are observed in nature. It is not clear how this came about. Any explanation for this phenomenon must allow the Sakharov conditions related to baryogenesis to have been satisfied at some time after the end of cosmological inflation. Current particle physics suggests asymmetries under which these conditions would be met, but these asymmetries appear to be too small to account for the observed baryon-antibaryon asymmetry of the universe.
The quark–gluon plasma that composes the universe cools until hadrons, including baryons such as protons and neutrons, can form. Initially, hadron/anti-hadron pairs could form, so matter and antimatter were in thermal equilibrium. However, as the temperature of the universe continued to fall, new hadron/anti-hadron pairs were no longer produced, and most of the newly formed hadrons and anti-hadrons annihilated each other, giving rise to pairs of high-energy photons. A comparatively small residue of hadrons remained at about 1 second of cosmic time, when this epoch ended.
Theory predicts that about 1 neutron remained for every 6 protons, with the ratio falling to 1:7 over time due to neutron decay. This is believed to be correct because, at a later stage, the neutrons and some of the protons fused, leaving hydrogen, a hydrogen isotope called deuterium, helium and other elements, which can be measured. A 1:7 ratio of hadrons would indeed produce the observed element ratios in the early and current universe.
Neutrino decoupling and cosmic neutrino background (CνB)
At approximately 1 second after the Big Bang neutrinos decouple and begin travelling freely through space. As neutrinos rarely interact with matter, these neutrinos still exist today, analogous to the much later cosmic microwave background emitted during recombination, around 370,000 years after the Big Bang. The neutrinos from this event have a very low energy, around 10 times smaller than is possible with present-day direct detection. Even high energy neutrinos are notoriously difficult to detect, so this cosmic neutrino background (CνB) may not be directly observed in detail for many years, if at all.
However, Big Bang cosmology makes many predictions about the CνB, and there is very strong indirect evidence that the CνB exists, both from Big Bang nucleosynthesis predictions of the helium abundance, and from anisotropies in the cosmic microwave background (CMB). One of these predictions is that neutrinos will have left a subtle imprint on the CMB. It is well known that the CMB has irregularities. Some of the CMB fluctuations were roughly regularly spaced, because of the effect of baryonic acoustic oscillations. In theory, the decoupled neutrinos should have had a very slight effect on the phase of the various CMB fluctuations.
In 2015, it was reported that such shifts had been detected in the CMB. Moreover, the fluctuations corresponded to neutrinos of almost exactly the temperature predicted by Big Bang theory (1.96 ± 0.02K compared to a prediction of 1.95K), and exactly three types of neutrino, the same number of neutrino flavors predicted by the Standard Model.
Possible formation of primordial black holes
Primordial black holes are a hypothetical type of black hole proposed in 1966, that may have formed during the so-called radiation-dominated era, due to the high densities and inhomogeneous conditions within the first second of cosmic time. Random fluctuations could lead to some regions becoming dense enough to undergo gravitational collapse, forming black holes. Current understandings and theories place tight limits on the abundance and mass of these objects.
Typically, primordial black hole formation requires density contrasts (regional variations in the universe's density) of around (10%), where is the average density of the universe. Several mechanisms could produce dense regions meeting this criterion during the early universe, including reheating, cosmological phase transitions and (in so-called "hybrid inflation models") axion inflation. Since primordial black holes didn't form from stellar gravitational collapse, their masses can be far below stellar mass (~2×1033g). Stephen Hawking calculated in 1971 that primordial black holes could have a mass as low as 10−5g. But they can have any size, so they could also be large, and may have contributed to the formation of galaxies.
The majority of hadrons and anti-hadrons annihilate each other at the end of the hadron epoch, leaving leptons (such as the electron, muons and certain neutrinos) and antileptons, dominating the mass of the universe.
The lepton epoch follows a similar path to the earlier hadron epoch. Initially leptons and antileptons are produced in pairs. About 10 seconds after the Big Bang the temperature of the universe falls to the point at which new lepton–antilepton pairs are no longer created and most remaining leptons and antileptons quickly annihilated each other, giving rise to pairs of high energy photons, and leaving a small residue of non-annihilated leptons
After most leptons and antileptons are annihilated at the end of the lepton epoch, most of the mass-energy in the universe is left in the form of photons. (Much of the rest of its mass-energy is in the form of neutrinos and other relativistic particles.) Therefore, the energy of the universe, and its overall behavior, is dominated by its photons. These photons continue to interact frequently with charged particles, i.e., electrons, protons and (eventually) nuclei. They continue to do so for about the next 370,000 years.
Nucleosynthesis of light elements
Between about 2 and 20 minutes after the Big Bang, the temperature and pressure of the universe allowed nuclear fusion to occur, giving rise to nuclei of a few light elements beyond hydrogen ("Big Bang nucleosynthesis"). About 25% of the protons, and all the neutrons fuse to form deuterium, a hydrogen isotope, and most of the deuterium quickly fuses to form helium-4.
Until now, the universe's large-scale dynamics and behavior have been determined mainly by radiation—meaning, those constituents that move relativistically (at or near the speed of light), such as photons and neutrinos. As the universe cools, from around 47,000 years (redshift z = 3600), the universe's large-scale behavior becomes dominated by matter instead. This occurs because the energy density of matter begins to exceed both the energy density of radiation and the vacuum energy density. Around or shortly after 47,000 years, the densities of non-relativistic matter (atomic nuclei) and relativistic radiation (photons) become equal, the Jeans length, which determines the smallest structures that can form (due to competition between gravitational attraction and pressure effects), begins to fall and perturbations, instead of being wiped out by free streaming radiation, can begin to grow in amplitude.
The properties of dark matter that allow it to collapse quickly without radiation pressure, also mean that it cannot lose energy by radiation either. Losing energy is necessary for particles to collapse into dense structures beyond a certain point. Therefore, dark matter collapses into huge but diffuse filaments and haloes, and not into stars or planets. Ordinary matter, which can lose energy by radiation, forms dense objects and also gas clouds when it collapses.
Recombination, photon decoupling, and the cosmic microwave background (CMB)
About 370,000 years after the Big Bang, two connected events occurred: the ending of recombination and photon decoupling. Recombination describes the ionized particles combining to form the first neutral atoms, and decoupling refers to the photons released ("decoupled") as the newly formed atoms settle into more stable energy states.
Just before recombination, the baryonic matter in the universe was at a temperature where it formed a hot ionized plasma. Most of the photons in the universe interacted with electrons and protons, and could not travel significant distances without interacting with ionized particles. As a result, the universe was opaque or "foggy". Although there was light, it was not possible to see, nor can we observe that light through telescopes.
The Dark Ages and large-scale structure emergence.
370 thousand to about 1 billion years after the Big Bang
After recombination and decoupling, the universe was transparent and had cooled enough to allow light to travel long distances, but there were no light-producing structures such as stars and galaxies. Stars and galaxies are formed when dense regions of gas form due to the action of gravity, and this takes a long time within a near-uniform density of gas and on the scale required, so it is estimated that stars did not exist for perhaps hundreds of millions of years after recombination.
This period, known as the Dark Ages, began around 370,000 years after the Big Bang. During the Dark Ages, the temperature of the universe cooled from some 4000 K to about 60 K (3727 °C to about −213 °C), and only two sources of photons existed: the photons released during recombination/decoupling (as neutral hydrogen atoms formed), which we can still detect today as the cosmic microwave background (CMB), and photons occasionally released by neutral hydrogen atoms, known as the 21 cm spin line of neutral hydrogen. The hydrogen spin line is in the microwave range of frequencies, and within 3 million years, the CMB photons had redshifted out of visible light to infrared; from that time until the first stars, there were no visible light photons. Other than perhaps some rare statistical anomalies, the universe was truly dark.
The first generation of stars, known as Population III stars, formed within a few hundred million years after the Big Bang. These stars were the first source of visible light in the universe after recombination. Structures may have begun to emerge from around 150 million years, and early galaxies emerged from around 380 to 700 million years. (We do not have separate observations of very early individual stars; the earliest observed stars are discovered as participants in very early galaxies.) As they emerged, the Dark Ages gradually ended. Because this process was gradual, the Dark Ages only fully ended around 1 billion years, as the universe took its present appearance.
There is also an observational effort underway to detect the faint 21 cm spin line radiation, as it is in principle an even more powerful tool than the cosmic microwave background for studying the early universe.
Speculative "habitable epoch"
For about 6.6 million years, between about 10 to 17 million years after the Big Bang (redshift 137–100), the background temperature was between 273–373 K (0–100 °C), a temperature compatible with liquid water and common biological chemical reactions. Abraham Loeb (2014) speculated that primitive life might in principle have appeared during this window, which he called the "habitable epoch of the early Universe". Loeb argues that carbon-based life might have evolved in a hypothetical pocket of the early universe that was dense enough both to generate at least one massive star that subsequently releases carbon in a supernova, and that was also dense enough to generate a planet. (Such dense pockets, if they existed, would have been extremely rare.) Life would also have required a heat differential, rather than just uniform background radiation; this could be provided by naturally occurring geothermal energy. Such life would likely have remained primitive; it is highly unlikely that intelligent life would have had sufficient time to evolve before the hypothetical oceans freeze over at the end of the habitable epoch
Earliest structures and stars emerge
The matter in the universe is around 84.5% cold dark matter and 15.5% "ordinary" matter. Since the start of the matter-dominated era, dark matter has gradually been gathering in huge spread-out (diffuse) filaments under the effects of gravity. Ordinary matter eventually gathers together faster than it would otherwise do, because of the presence of these concentrations of dark matter. It is also slightly more dense at regular distances due to early baryon acoustic oscillations (BAO) which became embedded into the distribution of matter when photons decoupled. Unlike dark matter, ordinary matter can lose energy by many routes, which means that as it collapses, it can lose the energy which would otherwise hold it apart, and collapse more quickly, and into denser forms. Ordinary matter gathers where dark matter is denser, and in those places it collapses into clouds of mainly hydrogen gas. The first stars and galaxies form from these clouds. Where numerous galaxies have formed, galaxy clusters and superclusters will eventually arise. Large voids with few stars will develop between them, marking where dark matter became less common.
As the first stars, dwarf galaxies and quasars gradually form, the intense radiation they emit reionizes much of the surrounding universe; splitting the neutral hydrogen atoms back into a plasma of free electrons and protons for the first time since recombination and decoupling.
Reionization is evidenced from observations of quasars. Quasars are a form of active galaxy, and the most luminous objects observed in the universe. Electrons in neutral hydrogen have specific patterns of absorbing photons, related to electron energy levels and called the Lyman series. Ionized hydrogen does not have electron energy levels of this kind. Therefore, light travelling through ionized hydrogen and neutral hydrogen shows different absorption lines.
Galaxies, clusters and superclusters
Matter continues to draw together under the influence of gravity, to form galaxies. The stars from this time period, known as Population II stars, are formed early on in this process, with more recent Population I stars formed later. Gravitational attraction also gradually pulls galaxies towards each other to form groups, clusters and superclusters. Hubble Ultra Deep Field observations has identified a number of small galaxies merging to form larger ones, at 800 million years of cosmic time (13 billion years ago). (This age estimate is now believed to be slightly overstated).
Myths and Legends
Many cultures have stories describing the origin of the world and universe. Cultures generally regard these stories as having some truth. There are however many differing beliefs in how these stories apply amongst those believing in a supernatural origin, ranging from a god directly creating the universe as it is now to a god just setting the "wheels in motion" (for example via mechanisms such as the big bang and evolution).
Ethnologists and anthropologists who study myths have developed various classification schemes for the various themes that appear in creation stories. For example, in one type of story, the world is born from a world egg; such stories include the Finnish epic poem Kalevala, the Chinese story of Pangu or the Indian Brahmanda Purana. In related stories, the universe is created by a single entity emanating or producing something by him- or herself, as in the Tibetan Buddhism concept of Adi-Buddha, the ancient Greek story of Gaia (Mother Earth), the Aztec goddess Coatlicue myth, the ancient Egyptian god Atum story, and the Judeo-Christian Genesis creation narrative in which the Abrahamic God created the universe. In another type of story, the universe is created from the union of male and female deities, as in the Maori story of Rangi and Papa. In other stories, the universe is created by crafting it from pre-existing materials, such as the corpse of a dead god—as from Tiamat in the Babylonian epic Enuma Elish or from the giant Ymir in Norse mythology—or from chaotic materials, as in Izanagi and Izanami in Japanese mythology. In other stories, the universe emanates from fundamental principles, such as Brahman and Prakrti, the creation myth of the Serers, or the yin and yang of the Tao.
- Sun: The star at the center of the entire realm.
- Mercury: The smallest and innermost planet named after the roman deity.
- Venus: The second-brightest natural object in the night sky after the Moon named after the roman deity.
- Earth: The most populated planet, containing humans and animals.
- Mars: A red planet named after the roman deity, it supposedly contains Martians.
- Jupiter: A gas giant with a mass one-thousandth that of the Sun named after the roman deity.
- Saturn: A gas giant with an average radius of about nine times that of Earth named after the roman deity.
- Uranus: The seventh planet from the Sun named after the Greek deity.
- Neptune: The fourth-largest planet by diameter named after the roman deity.
- Pluto: A dwarf planet in the Kuiper belt named after the roman deity.
- Nibiru: The home world of the Anunnaki.
- Yuggoth: A planet located at the very edge of the Solar System.
- Planet Popstar: A distant planet shaped like a yellow five-pointed star.
- Ripple Star: Home planet of the fairies.
- Patch Land: A soft planet made out of seven pieces of land.
- Halcandra: The original homeworld of "The Ancients."
- Although the universe is thought to be black, if the universe were viewed outside of a dark environment, its color would be beige, a rather pale beige, similar to the color of a latte - and that's why scientists called this tone "coffee with cosmic milk".