Streching the Cosmic canvas
What is the origin of everything that exists: space, time, particles, life, including every one of us?
Science says it is the so called inflaton scalar field (φ) (see Video 1) – a vacuum state with high potential energy density. This high energy vacuum state is the predecessor of all that exists, including us – the human beings.
So, how this vacuum state, containing no real particles created a multitude of them?
Here is the short story (see Figure 1):
Consider a very small initial spatial patch of typical length 10-33 centimeters. This patch is filled with vacuum scalar field. This field is called inflaton. The rate of stretching of the initial space patch is higher when the potential energy density of the field is higher. Initially the vacuum state of the inflaton field (φi position of the ball on Figure 1) has very high positive potential energy density (V). This high energy density causes a very fast radial push outwards from any spatial point. This push stretches exponentially fast the initially small patch of space. This is the so called cosmic inflationary phase. As the field φ slowly rolls forward on the plateau (see the arrow), it creates more and more space in exponential manner. At each point of the 3 dimensional space the energy density of the scalar field (φ) had minuscule fluctuations, i.e. deviations from some temporary average value of the field. Because of the fast expansion, these energy density fluctuations became spatially vastly stretched (Figure 2).
Figure 1. The initial value φi of the vacuum potential energy density V (φ) of the vacuum scalar field φ is very high. As a result the space is created exponentially fast. This is called the inflationary phase. When the field comes in steeper regions of the potential V(φ) (e.g. φf) the inflationary phase ends because very quickly the vacuum potential energy very quickly relaxes to the potential minimum( V). This is the current stable state of vacuum.
Eventually, at the end of inflationary phase (see φf on Figure 1), due to the steeper slope of the curve, the vacuum state potential energy starts to relax down more quickly into a low potential energy state. There it shortly oscillates around the potential minimum (see V on Figure 1), eventually settling there. In this way the initial high potential vacuum energy V (φ) is being transformed into a soup of interacting particles with high kinetic energy. The potential energy of the vacuum state becomes almost zero, but even today it has a minute positive value. This causes currently the space to be created with an immensely smaller, but still positive acceleration.
The spatial regions which, due to fluctuations has larger potential energy density created more particles and became denser and vice versa. These stretched fluctuations are now visible in the texture of the so called cosmic microwave background – a radiation fingerprint of the Universe when it was young (aged only 300 000 years – see Figure 2).
Figure 2. The pattern created on the Cosmic canvas (aged 300 000 years) with fine texture coming from stretched primordial energy density fluctuations.
The denser and sparser regions of space became responsible for the formation of the large-scale structure of the Universe such as: filaments and galaxy clusters and voids (see Figure 3), as well as smaller scale objects such as: stars and planets.
Gravity is the main interaction that forces the substance to self-organize into dynamic structures on many spatio-temporal scales. It is always attractive. Hence, denser regions are gravitationally more attractive and act as attractors of the surrounding matter. They are nucleuses of self-organization of all cosmic structures that exist.
Figure 3. The large scale structure pattern created on the Cosmic canvas as it is today (aged 13-14 billion years). These are galactic filaments (brighter regions) interspersed with giant voids (darker regions) where galaxies are absent. Each light pixel on the picture is around 100 galaxies.
The primordial differentiation (complexification)
Currently, we inhabit a low energy state of the vacuum. In this low energy context we know of four elementary interactions: gravitational, electromagnetic, strong and weak nuclear. These four interactions allow all of the complexity of our current world.
However, it is very probable that shortly after the phase of cosmic inflation there was only one, unified, type of interaction among the elementary field excitations (particles). Due to common symmetry principles interactions were not distinguishable. Because the temperature was dropping as a consequence of the spatial expansion, the particles interacted in an ever-changing context which led to the occurrence of sequence of instabilities of the vacuum (see Figure 4). The changing context brought about a cascade of symmetry breaking events and phase transitions during which a differentiation of forces happened. It was as if the vacuum was spontaneously deciding about settling in one out of a variety of equally possible low energy stable states. Deciding means existence of preference and preference breaks the symmetry (Figure 4). In this way the Universe self-organized in four distinct categories of organizing forces. The gravity, electromagnetic, the strong and weak nuclear forces became distinguishable.
Figure 4. Spontaneous symmetry breaking phase transition. For higher temperature the central symmetric position is stable. For lower temperature, however, it becomes unstable and spontaneously decides to which of the two equally possible minima (stable states) it will settle. This decision breaks the primordial symmetry. The vacuum decided to settle in the minimum on the right hand side.
Due to this primordial differentiation distinct elementary field excitations (particles) such as a variety of quarks, in the first second of the expansion formed more complex structures such as: nucleons (protons and neutrons). In the first several minutes already the lightest nuclei of hydrogen, helium 4 and some traces of deuterium, helium 3 and lithium were formed. The temperature was already too low for other elements to be formed. So, on Figure 2 we see the inhomogeneities of the hot gas that consists of these 3 elements. The formation of other elements will have to wait the epoch of formation of the first stars. However, the process of complexification had already started.
The Cosmic Art
Since the Cosmic canvas has been stretched and filled with mutually interacting vacuum excitations (particles), ever changing artistic patterns of immense beauty and complexity have been created constantly over the past 13-14 billion years. This, of course, includes also all living beings. Recall, that our bodies are dominantly filled by fields of virtual photons as well as by stable vacuum excitations such as: electrons and nucleons protons and neutrons. In this sense, each of us, living beings, is a unique artistic pattern of vacuum excitations.