Super force, temperature, massive BB singularity, pressure....all prior to formation of fundamental particle?
Any theory which attempts to explain the origin will have some assumptions, and mind you I was just careful about origin aspect as conveyed to 'Quantum wave'.
https://web.njit.edu/~gary/202/Lecture26.html
Cosmology and the Beginning of Time
The Instant of Creation
Given Hubble's Law, and the fact that the universe is expanding, we can imagine running the clock backwards, allowing space to shrink, until all of the galaxies are on top of one another. If we did that, we would find that the universe would heat up until stars and galaxies would be vaporized into their constituent atoms, which would all collect into a single point of unimaginably hot, dense matter and energy. From this simple consideration, we imagine that the universe began in such a hot, dense fireball, which we call the Big Bang. Did the universe really begin this way? We can never really know for sure, but we can predict some things we should see today, if the Big Bang actually happened. Astronomers have found that a lot of the predictions do hold up to experimental tests, so the theory is widely accepted now, but there are a lot of unanswered questions that we are still searching for the answers to.
The amazing fact is that we can trace the Big Bang back to its earliest moments, at least as far back as 10-10 s, and possibly as far back as 10-43s! This is an incredibly short time, and we can truthfully say that we can trace the evolution of the universe back to the first instant of creation. In so doing, we are probing not just the very earliest universe, but also the highest energy particle physics, so that particle physicists and astronomers are working on two aspects of the same puzzle.
Assuming that the Big Bang actually happened, what would the early moments of the universe be like? The figure below, from the text, shows an overview of all of time and space, which you can refer back to as we discuss the different eras of the past.
Eras of the Big BangThe eras of the universe, from the time of the Big Bang, are listed below. We will discuss each in turn.
- Planck Era (All four known forces are unified.)
- GUT (Grand Unified Theory) Era (Gravity "freezes out" and becomes distinct.)
- Electroweak Era (The nuclear strong force "freezes out" and becomes distinct.)
- Particle Era (particles begin to form)
- Era of Nucleosynthesis (nuclear fusion creates Helium, and tiny amount of heavier elements)
- Era of Nuclei (electrons are not yet bound to nuclei)
- Era of Atoms (electrons recombine to form neutral atoms, and the first stars are born)
- Era of Galaxies (Galaxies begin to form, leading up to the present)
The earliest eras were very short lasting, and very high energy. The first few eras are when the laws of physics were considerably different than they are know, but we can still predict some of the behavior. Let's look at each era in more detail:
Planck Era
The Planck Era is prior to 10-43 s after the Big Bang, when we believe that the four basic forces of nature, 1)
gravity, 2)
nuclear strong force, 3)
nuclear weak force, and 4)
electromagnetic force were combined into a single "super" force. The idea is somewhat like the different phases of water (ice, liquid, and vapor), which are all aspects of the same thing. You can imagine that at certain pressure and temperature there might be conditions in which these three phases of water become a single phase, no longer distinct. Physicists believe that we will eventually find a theory that succeeds in combining all four of these fundamental forces, but at present there is no such theory. (We have names for such a theory, however: supersymmetry, superstrings, or supergravity.) So we really do not know what the universe was like in the Planck Era. Some superstring theories call for spacetime to have 11 dimensions during this time.
GUT Era
The GUT Era is when three of the four fundamental forces are combined, but gravity has become distinct. There are a class of theories called Grand Unified Theories (GUTs) that attempt to describe all forces except gravity in a single framework. The leading type are so-called string theories, and some are partially successful, but there are further details to be worked out. Theorists would say that in the GUT Era the gravity force "froze out" of the universe. The GUT Era lasted from 10-43 s to 10-38 s. Near the end of this era, grand unified theories predict that the universe cooled to the point that the nuclear strong force began to freeze out, leaving three fundamental forces: gravity, the strong force, and the still combined electroweak force. This "phase transition" released a huge amount of energy, causing space to undergo a rapid
inflation. In a mere 10-36 s, pieces of our universe the size of an atomic nucleus might have grown to the size of our solar system. We will later discuss observations of the universe that seem to require such extreme inflation. Note that this inflation is very very large compared to the speed of light, but again, space itself is what is expanding, so it does not have to obey the speed limit of the speed of light.
Electroweak Era
During this era, only the electromagnetic and nuclear weak forces are still combined. The temperature of the universe at this stage is more than 1015 K, and there are no ordinary particles yet, just photons and pure energy. We do have a complete theory that can be used to understand the universe at the end of this era. By the time of 10-10 s, the temperature cools below 1015 K, and finally, the last of the fundamental forces, electromagnetic and nuclear weak forces, become distinct. We have also done particle physics experiments at energies corresponding to a temperature of 1015 K, so we can probe the Big Bang conditions experimentally from 10-10 s onward.
Particle Era
When the four fundamental forces were finally distinct, ordinary particles could start to form. However, both matter and anti-matter were formed in almost equal numbers, created out of the energetic photons present at that time. Once both types of matter were formed, a particle would not go very far before it met up with its anti-particle and annihilated to become pure energy again. During this era, particles continually were created and destroyed until, by 0.001 s (one millisecond), the universe had expanded and cooled far enough (to 1012 K) that creation and destruction of this kind ended. For some reason, the universe created slightly more matter particles than anti-matter particles. If the numbers had been exactly the same, the particles would eventually annihilate entirely and there would be only photons in the universe. This slight asymmetry for matter (1 billion and 1 protons for each 1 billion anti-protons) left us with all of the baryonic matter that we find today.
Era of Nucleosynthesis
When the universe was only 1 millisecond old, nuclei were hot enough and dense enough to fuse to create heavier elements, but it was so dense that the nuclei broke apart again as soon as they formed. This fusion and breakup continued until about 3 minutes after the Big Bang, when the universe cooled enough (109 K) that fusion ended. At this point, 75% of baryonic matter was in the form of hydrogen, 25% in the form of helium, and trace amounts were in the form of other atoms, mostly lithium. One of the great successes of the Big Bang theory is that it predicts just the
right amount of these different forms of matter. At the end of the Era of Nucleosynthesis, the universe contained the "primordial" mix of hydrogen, helium, and lithium that went into making the first stars. All heavier elements have been created by fusion inside of stars and during supernova explosions.
Era of Nuclei
During the next 500,000 years, the universe was too hot to form neutral atoms, and all of the particles were in the form of atomic nuclei (hydrogen, helium and a few lithium nuclei) and free electrons. As long as the universe was made up of these fully ionized particles, it was a largely featureless ball of hot plasma that could not condense to form galaxies or stars. During this time, the particles and photons (light) were locked into an equilibrium in which the photons could not escape. Finally, after 500,000 years, the universe cooled to 3000 K, and hydrogen and helium nuclei began to capture the free electrons. At this stage, photons could not react with the electrons except in narrow energy ranges, so most of the gas became transparent and the photons were free at last to stream out of the plasma and cross the universe.
It is these photons that we see today as the
cosmic microwave background, which we will discuss shortly.