[Excerpt from Everything Quantum...]
What do you think caused the Big Bang? What were the physical properties
of the Universe when it was (10 ^ -43) one hundred tredecillionth of a second
old?
The Era of Galaxies
The formal question is a bit more vauge so
let's explore the latter first. For the past few billion years we have lived in
the era of galaxies. The era of galaxies consist of the complex causal
phenomenon in which energy and mass are interchangeable,
hence the equation E = MC^2. This interchangeable energy produces massive
particles such as fermions (which are quarks and leptons) and bosons which
accelerate through the Higgs Field and thereby gain mass.
Exchange particles
such as gluons (which hold protons and neutrons in atomic nuclei together),
photons (which produces charge for the electrons in atomic orbitals thereby
creating the matter necessary for chemistry & biology) and gravitons (which
holds together large scale structures such as planets, stars, galaxies and
superclusters) are not affected by the Higgs Field.
Yet the exchange particle
that deals with nuclear reactions (W & Z bosons) is affected by the Higgs
Field thereby affecting the rate of radioactivity. This complex causal
structure of matter has produced everything we recognize in the universe today.
Fermions
The Standard Model includes 12 elementary particles of spin-½ known as fermions. According to the spin-statistics theorem, fermions respect the Pauli exclusion principle. Each fermion has a corresponding antiparticle.
The fermions of the Standard Model are classified according to how they interact (or equivalently, by what charges they carry). There are six quarks (up, down, charm, strange, top, bottom), and six leptons (electron, electron neutrino, muon, muon neutrino, tau, tau neutrino). Pairs from each classification are grouped together to form a generation, with corresponding particles exhibiting similar physical behavior (see table).
The defining property of the quarks is that they carry color charge, and hence, interact via the strong interaction. A phenomenon called color confinement results in quarks being perpetually (or at least since very soon after the start of the Big Bang) bound to one another, forming color-neutral composite particles (hadrons) containing either a quark and an antiquark (mesons) or three quarks (baryons). The familiar proton and the neutron are the two baryons having the smallest mass. Quarks also carry electric charge and weak isospin. Hence they interact with other fermions both electromagnetically and via the weak interaction.
The remaining six fermions do not carry colour charge and are called leptons. The three neutrinos do not carry electric charge either, so their motion is directly influenced only by the weak nuclear force, which makes them notoriously difficult to detect. However, by virtue of carrying an electric charge, the electron, muon, and tau all interact electromagnetically.
Each member of a generation has greater mass than the corresponding particles of lower generations. The first generation charged particles do not decay; hence all ordinary (baryonic) matter is made of such particles. Specifically, all atoms consist of electrons orbiting atomic nuclei ultimately constituted of up and down quarks. Second and third generations charged particles, on the other hand, decay with very short half lives, and are observed only in very high-energy environments. Neutrinos of all generations also do not decay, and pervade the universe, but rarely interact with baryonic matter.
Particle classifications
Mesons are bosons and hadrons; and baryons are hadrons and fermions. In particle physics, a hadron /ˈhædrɒn/ (Greek: ἁδρός, hadrós, "stout, thick") is a composite particle made of quarks held together by the strong force (in the same way as atoms and molecules are held together by the electromagnetic force). Hadrons are categorized into two families: baryons, such as protons and neutrons, made of three quarks and mesons, such as pions, made of one quark and one antiquark.
Gauge bosons (see Addendum: "Gauge Theory" below)
In the Standard Model, gauge bosons are defined as force carriers that mediate the strong, weak, and electromagnetic fundamental interactions.
Interactions in physics are the ways that particles influence other particles. At a macroscopic level, electromagnetism allows particles to interact with one another via electric and magnetic fields, and gravitation allows particles with mass to attract one another in accordance with Einstein's theory of general relativity. The Standard Model explains such forces as resulting from matter particles exchanging other particles, known as force mediating particles (strictly speaking, this is only so if interpreting literally what is actually an approximation method known as perturbation theory).
When a force-mediating particle is exchanged, at a macroscopic level the effect is equivalent to a force influencing both of them, and the particle is therefore said to have mediated (i.e., been the agent of) that force. The Feynman diagram calculations, which are a graphical representation of the perturbation theory approximation, invoke "force mediating particles", and when applied to analyze high-energy scattering experiments are in reasonable agreement with the data. However, perturbation theory (and with it the concept of a "force-mediating particle") fails in other situations. These include low-energy quantum chromodynamics, bound states, and solitons.
The gauge bosons of the Standard Model all have spin (as do matter particles). The value of the spin is 1, making them bosons. As a result, they do not follow the Pauli exclusion principle that constrains fermions: thus bosons (e.g. photons) do not have a theoretical limit on their spatial density (number per volume). The different types of gauge bosons are described below.
- Photons mediate the electromagnetic force between electrically charged particles. The photon is massless and is well-described by the theory of quantum electrodynamics.
- The W+, W−, and Z gauge bosons mediate the weak interactions between particles of different flavors (all quarks and leptons). They are massive, with the Z being more massive than the W±. The weak interactions involving the W± exclusively act on left-handed particles and right-handed antiparticles only. Furthermore, the W± carries an electric charge of +1 and −1 and couples to the electromagnetic interaction. The electrically neutral Z boson interacts with both left-handed particles and antiparticles. These three gauge bosons along with the photons are grouped together, as collectively mediating the electroweak interaction.
- The eight gluons mediate the strong interactions between color charged particles (the quarks). Gluons are massless. The eightfold multiplicity of gluons is labeled by a combination of color and anticolor charge (e.g. red–antigreen). Because the gluons have an effective color charge, they can also interact among themselves. The gluons and their interactions are described by the theory of quantum chromodynamics.
The interactions between all the particles described by the Standard Model are summarized by the diagrams on the right of this section.
Higgs boson
http://en.wikipedia.org/wiki/Standard_model_of_particle_physics
The Higgs particle is a massive scalar elementary particle theorized by Robert Brout, François Englert, Peter Higgs, Gerald Guralnik, C. R. Hagen, and Tom Kibble in 1964 (see 1964 PRL symmetry breaking papers) and is a key building block in the Standard Model. It has no intrinsic spin, and for that reason is classified as a boson (like the gauge bosons, which have integer spin).
The Higgs particle is a massive scalar elementary particle theorized by Robert Brout, François Englert, Peter Higgs, Gerald Guralnik, C. R. Hagen, and Tom Kibble in 1964 (see 1964 PRL symmetry breaking papers) and is a key building block in the Standard Model. It has no intrinsic spin, and for that reason is classified as a boson (like the gauge bosons, which have integer spin).
The Higgs boson plays a unique role in the Standard Model, by explaining why the other elementary particles, except the photon and gluon, are massive. In particular, the Higgs boson would explain why the photon has no mass, while the W and Z bosons are very heavy. Elementary particle masses, and the differences between electromagnetism (mediated by the photon) and the weak force (mediated by the W and Z bosons), are critical to many aspects of the structure of microscopic (and hence macroscopic) matter. In electroweak theory, the Higgs boson generates the masses of the leptons (electron, muon, and tau) and quarks. As the Higgs boson is massive, it must interact with itself.
Because the Higgs boson is a very massive particle and also decays almost immediately when created, only a very high energy particle accelerator can observe and record it. Experiments to confirm and determine the nature of the Higgs boson using the Large Hadron Collider (LHC) at CERN began in early 2010, and were performed at Fermilab's Tevatron until its closure in late 2011. Mathematical consistency of the Standard Model requires that any mechanism capable of generating the masses of elementary particles become visible at energies above 1.4 TeV; therefore, the LHC (designed to collide two 7 to 8 TeV proton beams) was built to answer the question of whether the Higgs boson actually exists.
On 4 July 2012, the two main experiments at the LHC (ATLAS and CMS) both reported independently that they found a new particle with a mass of about 125 GeV/c2 (about 133 proton masses, on the order of 10−25 kg), which is "consistent with the Higgs boson." Although it has several properties similar to the predicted "simplest" Higgs, they acknowledged that further work would be needed to conclude that it is indeed the Higgs boson, and exactly which version of the Standard Model Higgs is best supported if confirmed.
Earlier Eras
The Era of Atoms saw the formation of atoms and the release of photons to form background radiation. During this time mega structures began to form from the plasma abounding. This occurred when the universe was 300,000 years old.
When the universe was around 3 minutes old the temperature was around 10^9 kelvin. This era was known as the "Era of Nuclei" which consisted of the hot plasma of ionized hydrogen nuclei, helium nuclei, traces of lithium nuclei and free electrons. This era lasted for around 380,000 years.
When the universe was 0.001 of a second old it was compiled of protons and neutrons which was left over from a previous era thereby fusing into heavier nuclei. This was known as the "Era of Nucleosynthesis".
The Particle Era held powerful radiation that filled the universe spontaneously produced matter and antimatter particles that almost immediately annihilated each other. Here, the electromagnetic and electroweak forces became distinct. Around this time the Universe was 10^ -10 of a second old and the temperature was 10^15 kelvin.
At 10^-35 seconds The Electroweak Era began marking a very important transition in the physical universe (it is called the "Electroweak Era" because Scientist believe that at this time the electromagnetic force and weak nuclear forces were one unified force). The temperature at this time was 10^15 kelvin.
The GUT Era (which is an acronym for Grand Unified Theories) is a bit more mysterious and ambiguous for Scientist. During this time the universe was around 10^ - 43 of a second old and the temperture was around 10 ^ 29 kelvin which means this era only lasted for a trillion-trillion-trillionth of a second.
And lastly there was the Planck Era which was when the universe was older than (10 ^ -43) one hundred tredecillionth of a second old and temperatures were above 10^32 kelvin. According to quantum mechanics there was a plethora of energy fluctuations that produced a rapidly changing gravitational field that randomly warped the spacetime continuum.
The Planck Era's random fluctuations are so stochastic that it causes discrepancies between our scientific knowledge of General Relativity and Quantum Mechanics (similarly to the mathematical discrepancies that appear when you surpass the event horizon and enter the singularity of a black hole). Perhaps Heterotic String Theory can answer the question of the "Planck Era" and the beginning of the universe. This is an area where bosonic string and superstring theory are hybridized. By asking the question what happened before the Big Bang brings us to the question of multi-universes (multiverses) and how they are birthed and affect one another.
In conclusion, What do you think cause the Big Bang? What were the physical properties of the Universe when it was in the Planck Era? And moreover, Do you think there was something before the big bang?
- Excerpt from Everything Quantum
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Addendum: Gauge Theory
[Excerpt from Everything Quantum...]
Phases of gauge theories
One of the most fundamental questions we can ask about a given gauge theory is its phase diagram. In the Standard Model, we observe three fundamentally different types of behavior:
QCD is in a confined phase at zero temperature, while the electroweak sector of the Standard Model combines Coulomb and Higgs phases.
Our current understanding of the phase structure of gauge theories owes much to the modern theory of phase transitions and critical phenomena, but has developed into a subject of extensive study. After reviewing some fundamental concepts of phase transitions and finite-temperature gauge theories, we discuss some recent work that broadly extends our knowledge of the mechanisms that determine the phase structure of gauge theories.
A new class of models with a rich phase structure has been discovered, generalizing our understanding of the confinement–deconfinement transition in finite-temperature gauge theories. Models in this class have spacetime topologies with one or more compact directions. On R3 × S1, the addition of double-trace deformations or periodic adjoint fermions to a gauge theory can yield a confined phase in the region where the S1 circumference L is small, so that the coupling constant is small, and semiclassical methods are applicable.
In this region, Euclidean monopole solutions, which are constituents of finite-temperature instantons, play a crucial role in the calculation of a non-perturbative string tension. We review the techniques used to analyze this new class of models and the results obtained so far, as well as their application to finite-temperature phase structure, conformal phases of gauge theories and the large-N limit.
For More Discussion on Creational Quantum Evolution -
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