Harari Rishon Model
Encyclopedia
The rishon model is the earliest efforts to develop a preon
model to explain the phenomena appearing in the Standard Model
(SM) of particle physics
. It was first developed by Haim Harari
and Michael A. Shupe (independently of each other), and later expanded by Harari and his then-student Nathan Seiberg
.
, or Tohu which means "unformed"
in Hebrew Genesis) and V ("Vanishes", since it is electrically neutral, or Vohu which means "void" in Hebrew Genesis). All lepton
s and all flavour
s of quark
s are three-rishon ordered triplets. These groups of three rishons have spin-½
. They are as follows:
Each rishon has a corresponding antiparticle. Hence: = electron
; = electron antineutrino;, , = three colours of up antiquarks
;, , = three colours of down quark
s.
The W+ boson
= TTTVVV;
The W− boson
= .
Baryon number (B) and lepton number
(L) are not conserved, but the quantity B−L is conserved. A baryon number violating process (such as proton decay
) in the model would be
/|\ /|\ /|\ /|\
In the expanded Harari–Seiberg versionhttp://www.weizmann.ac.il/home/harari/files/Nuclear_PhysicsB_Vol204.pdf the rishons possess color and hypercolor, explaining why the only composites are the observed quarks and leptons. Under certain assumptions, it is possible to show that the model allows exactly for three generations of quarks and leptons.
for the existence of substructure within quarks and leptons, but there is no profound reason why such a substructure may not be revealed at shorter distances. In 2008, Piotr Zenczykowski has derived the RM by starting from a non-relativistic O(6) phase space
. Such model is based on fundamental principles and the structure of Clifford algebras, and fully recovers the RM by naturally explaining several obscure and otherwise artificial features of the original model.
Preon
In particle physics, preons are postulated "point-like" particles, conceived to be subcomponents of quarks and leptons. The word was coined by Jogesh Pati and Abdus Salam in 1974...
model to explain the phenomena appearing in the Standard Model
Standard Model
The Standard Model of particle physics is a theory concerning the electromagnetic, weak, and strong nuclear interactions, which mediate the dynamics of the known subatomic particles. Developed throughout the mid to late 20th century, the current formulation was finalized in the mid 1970s upon...
(SM) of particle physics
Particle physics
Particle physics is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. In current understanding, particles are excitations of quantum fields and interact following their dynamics...
. It was first developed by Haim Harari
Haim Harari
Haim Harari is an Israeli theoretical physicist who has made contributions in particle physics, science education, and other fields.- Birth and education :...
and Michael A. Shupe (independently of each other), and later expanded by Harari and his then-student Nathan Seiberg
Nathan Seiberg
Nathan "Nati" Seiberg is an Israeli American theoretical physicist who works on string theory. He was recipient of a 1996 MacArthur Fellowship and the Dannie Heineman Prize for Mathematical Physics in 1998. He is currently a professor at the Institute for Advanced Study in Princeton, New Jersey, USA...
.
The model
The model has two kinds of fundamental particles called rishons (which means "primary" in Hebrew). They are T ("Third" since it has an electric charge of ⅓ eElementary charge
The elementary charge, usually denoted as e, is the electric charge carried by a single proton, or equivalently, the absolute value of the electric charge carried by a single electron. This elementary charge is a fundamental physical constant. To avoid confusion over its sign, e is sometimes called...
, or Tohu which means "unformed"
Tohu va bohu
Tohu wa bohu is a Biblical Hebrew phrase found in the Book of Genesis 1:2. It is usually translated "formless and empty," or some variation of the same, and describes the condition of the earth before God said, "Let there be light." Precise translation of the phrase is difficult, as only the first...
in Hebrew Genesis) and V ("Vanishes", since it is electrically neutral, or Vohu which means "void" in Hebrew Genesis). All lepton
Lepton
A lepton is an elementary particle and a fundamental constituent of matter. The best known of all leptons is the electron which governs nearly all of chemistry as it is found in atoms and is directly tied to all chemical properties. Two main classes of leptons exist: charged leptons , and neutral...
s and all flavour
Flavour (particle physics)
In particle physics, flavour or flavor is a quantum number of elementary particles. In quantum chromodynamics, flavour is a global symmetry...
s of quark
Quark
A quark is an elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. Due to a phenomenon known as color confinement, quarks are never directly...
s are three-rishon ordered triplets. These groups of three rishons have spin-½
Spin-½
In quantum mechanics, spin is an intrinsic property of all elementary particles. Fermions, the particles that constitute ordinary matter, have half-integer spin. Spin-½ particles constitute an important subset of such fermions. All known elementary fermions have a spin of ½.- Overview :Particles...
. They are as follows:
- TTT = antielectron;
- VVV = electron neutrinoElectron neutrinoThe electron neutrino is a subatomic lepton elementary particle which has no net electric charge. Together with the electron it forms the first generation of leptons, hence its name electron neutrino...
; - TTV, TVT and VTT = three colourColor chargeIn particle physics, color charge is a property of quarks and gluons that is related to the particles' strong interactions in the theory of quantum chromodynamics . Color charge has analogies with the notion of electric charge of particles, but because of the mathematical complications of QCD,...
s of up quarkUp quarkThe up quark or u quark is the lightest of all quarks, a type of elementary particle, and a major constituent of matter. It, along with the down quark, forms the neutrons and protons of atomic nuclei...
s; - TVV, VTV and VVT = three colours of down antiquarksDown quarkThe down quark or d quark is the second-lightest of all quarks, a type of elementary particle, and a major constituent of matter. It, along with the up quark, forms the neutrons and protons of atomic nuclei...
.
Each rishon has a corresponding antiparticle. Hence: = electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...
; = electron antineutrino;, , = three colours of up antiquarks
Up quark
The up quark or u quark is the lightest of all quarks, a type of elementary particle, and a major constituent of matter. It, along with the down quark, forms the neutrons and protons of atomic nuclei...
;, , = three colours of down quark
Down quark
The down quark or d quark is the second-lightest of all quarks, a type of elementary particle, and a major constituent of matter. It, along with the up quark, forms the neutrons and protons of atomic nuclei...
s.
The W+ boson
W and Z bosons
The W and Z bosons are the elementary particles that mediate the weak interaction; their symbols are , and . The W bosons have a positive and negative electric charge of 1 elementary charge respectively and are each other's antiparticle. The Z boson is electrically neutral and its own...
= TTTVVV;
The W− boson
W and Z bosons
The W and Z bosons are the elementary particles that mediate the weak interaction; their symbols are , and . The W bosons have a positive and negative electric charge of 1 elementary charge respectively and are each other's antiparticle. The Z boson is electrically neutral and its own...
= .
Baryon number (B) and lepton number
Lepton number
In particle physics, the lepton number is the number of leptons minus the number of antileptons.In equation form,so all leptons have assigned a value of +1, antileptons −1, and non-leptonic particles 0...
(L) are not conserved, but the quantity B−L is conserved. A baryon number violating process (such as proton decay
Proton decay
In particle physics, proton decay is a hypothetical form of radioactive decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a positron...
) in the model would be
/|\ /|\ /|\ /|\
- MatterMatterMatter is a general term for the substance of which all physical objects consist. Typically, matter includes atoms and other particles which have mass. A common way of defining matter is as anything that has mass and occupies volume...
and antimatterAntimatterIn particle physics, antimatter is the extension of the concept of the antiparticle to matter, where antimatter is composed of antiparticles in the same way that normal matter is composed of particles...
are equally abundant in nature in the RM. - Higher generationGeneration (particle physics)In particle physics, a generation is a division of the elementary particles. Between generations, particles differ by their quantum number and mass, but their interactions are identical....
leptons and quarks are presumed to be excited states of first generation leptons and quarks. - MassMassMass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...
is not explained.
In the expanded Harari–Seiberg versionhttp://www.weizmann.ac.il/home/harari/files/Nuclear_PhysicsB_Vol204.pdf the rishons possess color and hypercolor, explaining why the only composites are the observed quarks and leptons. Under certain assumptions, it is possible to show that the model allows exactly for three generations of quarks and leptons.
Evidence
Currently, there is no scientific evidenceScientific evidence
Scientific evidence has no universally accepted definition but generally refers to evidence which serves to either support or counter a scientific theory or hypothesis. Such evidence is generally expected to be empirical and properly documented in accordance with scientific method such as is...
for the existence of substructure within quarks and leptons, but there is no profound reason why such a substructure may not be revealed at shorter distances. In 2008, Piotr Zenczykowski has derived the RM by starting from a non-relativistic O(6) phase space
Phase space
In mathematics and physics, a phase space, introduced by Willard Gibbs in 1901, is a space in which all possible states of a system are represented, with each possible state of the system corresponding to one unique point in the phase space...
. Such model is based on fundamental principles and the structure of Clifford algebras, and fully recovers the RM by naturally explaining several obscure and otherwise artificial features of the original model.
In popular culture
- Science fictionScience fictionScience fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...
authorAuthorAn author is broadly defined as "the person who originates or gives existence to anything" and that authorship determines responsibility for what is created. Narrowly defined, an author is the originator of any written work.-Legal significance:...
Vonda McIntyreVonda McIntyreVonda Neel McIntyre is an American science fiction author.-Biography:Vonda N. McIntyre, daughter of H. Neel and Vonda B. Keith McIntyre, earned a degree in biology from the University of Washington in 1970. That same year, she attended the Clarion Writers Workshop, founded at the Clarion...
, in her novelizations of the scripts of the movies Star Trek II: The Wrath of Khan and Star Trek III: The Search for Spock suggested that the Genesis effect was a result of a newly-discovered rishon-like substructure to matter. - Science fiction author James P. HoganJames P. Hogan (writer)James Patrick Hogan was a British science fiction author.-Biography:Hogan was born in London, England. He was raised in the Portobello Road area on the west side of London...
in his novel Voyage from YesteryearVoyage from YesteryearVoyage from Yesteryear is a 1982 science fiction novel by the author James P. Hogan. It explores themes of anarchism and the appropriateness of certain social values in the context of high-technology....
explicitly postulated a rishon-like model in the development of antimatter weapons and energy sources.