The term "boson" refers to a category of subatomic particles that obey Bose-Einstein statistics, which means they can occupy the same quantum state as other bosons. This characteristic distinguishes them from fermions, which follow the Pauli exclusion principle and cannot occupy the same state. Bosons include force carrier particles and have integer values of spin (0, 1, 2, etc.).
Bosonization is a theoretical technique in quantum field theory and statistical mechanics that relates fermionic systems to bosonic systems. It is particularly useful in one-dimensional systems, where it can simplify the analysis of interacting fermions by transforming them into an equivalent model of non-interacting bosons.
C parity, or even parity, is a method of error detection used in data communications and data storage systems. In parity checking, a binary digit (bit) is added to a group of bits to ensure that the total number of bits with the value of one (1) is either even or odd.
Cluster decomposition is a concept often used in various fields, including mathematics, physics, and computer science. While it can have specific definitions depending on the context, the general idea revolves around breaking down a complex structure or system into simpler, smaller parts or clusters that are more manageable for analysis and understanding.
The Higgs boson is a subatomic particle associated with the Higgs field, which is a fundamental field believed to give mass to other elementary particles through the Higgs mechanism. It was first predicted by physicist Peter Higgs and others in the 1960s as part of the Standard Model of particle physics, which describes the electromagnetic, weak, and strong nuclear interactions.
Infrared divergence refers to a type of divergence that occurs in quantum field theory (QFT) and certain fields of theoretical physics when dealing with low-energy (or long-wavelength) phenomena. Specifically, it manifests when evaluating Feynman integrals or loop diagrams that include virtual particles with very low momenta (approaching zero). In such scenarios, the contributions from these low-energy states can lead to integrals that diverge, meaning they yield infinite values.
The LSZ reduction formula, named after Lüders, Steinweg, and Ziman, is a fundamental result in quantum field theory (QFT) that relates S-matrix elements to time-ordered correlation functions (or Green's functions). It provides a method for calculating the S-matrix (which describes the scattering processes) from the theoretical correlation functions computed in a given quantum field theory.
Infrared safety in particle physics is a concept that addresses the behavior of certain types of divergences (infinities) that can arise in quantum field theory calculations, particularly in the context of high-energy collisions and the production of particles. In particle collisions, particularly those occurring at high energies, one can encounter divergent contributions from virtual photons (or other massless particles) due to soft emissions—where particles are produced with very low energies.
The term "multiplicative quantum number" does not refer to a standard concept in quantum mechanics or quantum chemistry. However, it may be a conflation or misunderstanding of related terms that involve quantum numbers. In quantum mechanics, quantum numbers are used to describe the quantized states of a system, such as an electron in an atom. The primary quantum numbers usually include: 1. **Principal quantum number (n)**: Indicates the energy level of the electron.
In quantum field theory (QFT), the partition function is a central concept that plays a role analogous to that in statistical mechanics. It encapsulates the statistical properties of a quantum system and is crucial for deriving various physical observables. ### Definition The partition function in QFT, often denoted as \( Z \), is defined as the functional integral over all possible field configurations of a given theory.
Path-ordering is a concept used primarily in the context of quantum field theory and the mathematical formulation of quantum mechanics. It is particularly relevant in the computation of correlation functions and in the development of techniques like perturbation theory. In quantum field theory, when dealing with time-dependent operators, the need arises to define the order in which these operators act because the non-commutativity of operators can lead to different results depending on their order. Path-ordering provides a systematic way to handle this issue.
Ultraviolet (UV) divergence is a concept in quantum field theory and quantum mechanics that refers to the phenomenon where certain integrals, especially those that arise in the calculation of particle interactions and vacuum fluctuations, yield infinite results when evaluated at high energy (or short distance) scales. This is particularly relevant in theories like quantum electrodynamics (QED) and quantum chromodynamics (QCD), where loop diagrams (representing virtual particles) can produce divergences.
In physics, a "tadpole" typically refers to a specific kind of diagram used in quantum field theory, especially in the context of perturbation theory in quantum electrodynamics and other quantum field theories. The term is most often associated with Feynman diagrams. In this context, a tadpole diagram represents a one-point function or a loop diagram that has one external vertex and a loop.
The quantum vacuum, often referred to simply as the "vacuum" in the context of quantum field theory, is a fundamental concept in modern physics. Contrary to the classical notion of a vacuum as an empty space devoid of matter, the quantum vacuum is a dynamic state filled with fluctuating energy and virtual particles that constantly pop in and out of existence.
Quantum inequalities are a concept in quantum field theory, particularly related to the study of the energy conditions in curved spacetime. They provide constraints on the local energy density allowed by quantum fields, especially in the context of quantum fluctuations in vacuum states. In classical general relativity, the energy conditions (such as the weak energy condition, the strong energy condition, etc.) define certain properties that energy-momentum tensors must satisfy to ensure physically reasonable conditions, such as avoiding certain types of singularities or pathological behaviors.
The soft graviton theorem is a result in theoretical physics, particularly in the context of quantum gravity and scattering amplitudes. It belongs to a broader class of soft theorems, which describe how physical interactions behave when particles become increasingly low-energy or "soft." Specifically, the soft graviton theorem states that the emission of soft gravitons in scattering processes can be understood in terms of the behavior of the quantum field theory of gravity.
Transactional Interpretation (TI) is an interpretation of quantum mechanics proposed by physicists John G. Cramer in the 1980s. It is designed to address some of the conceptual problems related to the standard Copenhagen interpretation, particularly the role of the observer and the nature of wave function collapse. The central idea of the Transactional Interpretation is that quantum events involve a "handshake" between waves traveling forward in time and those traveling backward in time.
Twistor theory is a mathematical framework developed by the British mathematician Roger Penrose in the 1960s. It is designed to provide a new perspective on the geometry of space-time and the fundamental structures of physical theories, particularly in the context of general relativity and quantum gravity. At its core, twistor theory transforms the conventional approach to understanding space-time by introducing a new set of mathematical objects called "twistors.
The Uehling potential, named after the physicist Eugene Uehling, is an important concept in quantum mechanics and field theory, particularly in the context of quantum electrodynamics (QED). It refers to a potential energy associated with the interaction between charged particles due to vacuum polarization effects. Vacuum polarization is a phenomenon where a vacuum behaves like a medium due to the temporary creation of virtual particle-antiparticle pairs.
The Weinberg–Witten theorem is a result in theoretical physics, specifically in the context of quantum field theory and general relativity. It was formulated by Steven Weinberg and Edward Witten and addresses the relationship between certain types of symmetries and the properties of particles. The theorem asserts that any massless particle with spin greater than 1 (i.e., a spin-2, spin-3, etc.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact