What is "standard model"

The Standard Model of particle physics is a theory concerning the electromagnetic, weak, and strong nuclear interactions, as well as classifying all the subatomic particles known. It was developed throughout the latter half of the 20th century, as a collaborative effort of scientists around the world. The current formulation was finalized in the mid-1970s upon experimental confirmation of the existence of quarks. Since then, discoveries of the top quark (1995), the tau neutrino (2000), and the Higgs boson (2012) have given further credence to the Standard Model. Because of its success in explaining a wide variety of experimental results, the Standard Model is sometimes regarded as the "theory of almost everything".

Although the Standard Model is believed to be theoretically self-consistent and has demonstrated huge and continued successes in providing experimental predictions, it does leave some phenomena unexplained and it falls short of being a complete theory of fundamental interactions. It does not incorporate the full theory of gravitation as described by general relativity, or account for the accelerating expansion of the universe (as possibly described by dark energy). The model does not contain any viable dark matter particle that possesses all of the required properties deduced from observational cosmology. It also does not incorporate neutrino oscillations (and their non-zero masses).

The development of the Standard Model was driven by theoretical and experimental particle physicists alike. For theorists, the Standard Model is a paradigm of a quantum field theory, which exhibits a wide range of physics including spontaneous symmetry breaking, anomalies and non-perturbative behavior. It is used as a basis for building more exotic models that incorporate hypothetical particles, extra dimensions, and elaborate symmetries (such as supersymmetry) in an attempt to explain experimental results at variance with the Standard Model, such as the existence of dark matter and neutrino oscillations.

This article describes the mathematics of the Standard Model of particle physics, a gauge quantum field theory containing the internal symmetries of the unitary product group . The theory is commonly viewed as containing the fundamental set of particles – the leptons, quarks, gauge bosons and the Higgs particle.

The Standard Model is renormalizable and mathematically self-consistent, however despite having huge and continued successes in providing experimental predictions it does leave some unexplained phenomena. In particular, although the physics of special relativity is incorporated, general relativity is not, and the Standard Model will fail at energies or distances where the graviton is expected to emerge. Therefore, in a modern field theory context, it is seen as an effective field theory.

This article requires some background in physics and mathematics, but is designed as both an introduction and a reference.

In cryptography the standard model is the model of computation in which the adversary is only limited by the amount of time and computational power available. Other names used are bare model and plain model.

Cryptographic schemes are usually based on complexity assumptions, which state that some problems, such as factorization, cannot be solved in polynomial time. Schemes which can be proven secure using only complexity assumptions are said to be secure in the standard model. Security proofs are notoriously difficult to achieve in the standard model, so in many proofs, cryptographic primitives are replaced by idealized versions. The most usual example of this technique, known as the random oracle model, involves replacing a cryptographic hash function with a genuinely random function. Another example is the generic group model, where the adversary is given access to a randomly chosen encoding of a group, instead of the finite field or elliptic curve groups used in practice.

Other models used invoke trusted third parties to perform some task without cheating; for example, the public key infrastructure (PKI) model requires a certificate authority, which if it were dishonest, could produce fake certificates and use them to forge signatures, or mount a man in the middle attack to read encrypted messages. Other examples of this type are the common random string model and the common reference string model, where it is assumed that all parties have access to some string chosen uniformly at random or a string chosen according to some other probability distribution respectively. These models are often used for non-interactive zero-knowledge proofs (NIZK). In some applications, such as the Dolev-Dwork-Naor encryption scheme, it makes sense for a particular party to generate the common reference string, while in other applications, the common reference string must be generated by a trusted third party. Collectively, these models are referred to as models with special setup assumptions.

Standard model may refer to:

• Standard Model of particle physics
• The mathematical formulation of the Standard Model of particle physics
• The Standard Solar Model of solar astrophysics
• The Lambda-CDM model, the standard model of big bang cosmology
• Standard model (cryptography)
• Intended interpretation of a syntactical system, called standard model in mathematical logic
• The standard models of set theory
• The Standard Model (Exhibition) held in Stockholm, 2009

Standard Model is the title of an exhibition held between 1 October and 25 October 2009 at the Nordin Gallery, Stockholm. The exhibition was made in collaboration between Swedish artist Karl Tuikkanen and London based Australian artist David Brazier and represents the first physical manifestation of their artistic partnership exploring ideas of communication and collaboration mediated through the internet.