Quantum Mechanics

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The study of how particles and waves interact, and how they can be described mathematically.

Wave-particle duality: The concept that matter and energy can exist as both a wave and a particle simultaneously.
Probability and statistics: The mathematical tools used to describe the behavior of quantum systems.
Schrödinger equation: A fundamental equation of quantum mechanics that describes the behavior of a quantum system.
Quantum states: A description of a quantum system that includes its energy, position, and other relevant properties.
Wavefunctions: Mathematically describing quantum states.
Orbital theory: The study of electron arrangements in atoms and molecules.
Quantum numbers: Numbers that describe the properties of an electron in an atom.
Spin: A fundamental property of all particles that leads to their magnetic behavior.
Operators: Mathematical tools used to describe quantum mechanical systems.
Eigenvalues and eigenvectors: The properties of operators that describe the states of a quantum system.
Heisenberg uncertainty principle: The principle that it is impossible to simultaneously know the precise values of certain pairs of properties of a quantum system.
Uncertainty and measurement: The role of measurement in quantum mechanics and how it affects the properties of particles.
Superposition: A principle of quantum mechanics that states that particles can exist in multiple states simultaneously.
Entanglement: A phenomenon in which the states of two particles are correlated even if they are separated by a distance.
Quantum tunneling: A phenomenon in which particles can pass through potential barriers even if they do not have sufficient energy to do so classically.
Time evolution: The behavior of quantum systems over time and the role of the Schrödinger equation.
Approximation methods: The mathematical tools used to simplify the calculation of quantum mechanical systems.
Applications of quantum mechanics: The various fields in which quantum mechanics plays a role, including chemistry, physics, and materials science.
Non-relativistic quantum mechanics: Mathematical framework that describes the behavior of non-relativistic particles such as electrons and atoms.
Relativistic quantum mechanics: Mathematical framework that incorporates relativistic effects, such as the speed of light, into the description of the behavior of particles such as electrons and atoms.
Quantum field theory: Mathematical framework that extends quantum mechanics to include the behavior of fields, such as the electromagnetic field.
Density functional theory: A theory that uses the electron density of a system to determine its energy and properties.
Quantum mechanics of solids: Mathematical framework that describes the behavior of electrons and atoms in solids, including the band structure and electronic properties of materials.
Quantum computing: The use of quantum mechanics to process and manipulate data, with applications in cryptography and computer science.
Quantum optics: The study of how light and matter interact at the quantum level, with applications in communication and sensing.
Quantum information theory: The study of quantum mechanics as it relates to the processing and transmission of information, with applications in computer science and cryptography.
Quantum thermodynamics: The application of quantum mechanics to the study of thermodynamics, including the behavior of small systems and the limits of energy conversion.
Quantum chemistry: The application of quantum mechanics to the study of chemical systems and reactions, with applications in materials science, drug design, and catalysis.
- "Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles."
- "It is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science."
- "Quantum mechanics differs from classical physics in that energy, momentum, angular momentum, and other quantities of a bound system are restricted to discrete values (quantization); objects have characteristics of both particles and waves (wave-particle duality); and there are limits to how accurately the value of a physical quantity can be predicted prior to its measurement, given a complete set of initial conditions (the uncertainty principle)."
- "Quantum mechanics arose gradually from theories to explain observations that could not be reconciled with classical physics, such as Max Planck's solution in 1900 to the black-body radiation problem, and the correspondence between energy and frequency in Albert Einstein's 1905 paper, which explained the photoelectric effect."
- "These early attempts to understand microscopic phenomena, now known as the 'old quantum theory,' led to the full development of quantum mechanics in the mid-1920s by Niels Bohr, Erwin Schrödinger, Werner Heisenberg, Max Born, Paul Dirac, and others."
- "In one of them, a mathematical entity called the wave function provides information, in the form of probability amplitudes, about what measurements of a particle's energy, momentum, and other physical properties may yield."
- "Objects have characteristics of both particles and waves (wave-particle duality)."
- "Most theories in classical physics can be derived from quantum mechanics as an approximation valid at large (macroscopic) scale."
- "Max Planck's solution in 1900 to the black-body radiation problem."
- "Albert Einstein's 1905 paper, which explained the photoelectric effect."
- "There are limits to how accurately the value of a physical quantity can be predicted prior to its measurement, given a complete set of initial conditions (the uncertainty principle)."
- "Quantum mechanics is the foundation of all quantum physics."
- "Energy, momentum, angular momentum, and other quantities of a bound system are restricted to discrete values (quantization)."
- "These early attempts to understand microscopic phenomena, now known as the 'old quantum theory.'"
- "Classical physics describes many aspects of nature at an ordinary (macroscopic) scale."
- "The modern theory is formulated in various specially developed mathematical formalisms."
- "Quantum mechanics provides a description of the physical properties of nature at the scale of atoms and subatomic particles."
- "Quantum mechanics is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science."
- "The wave function provides information, in the form of probability amplitudes, about what measurements of a particle's energy, momentum, and other physical properties may yield."
- "The old quantum theory led to the full development of quantum mechanics in the mid-1920s by Niels Bohr, Erwin Schrödinger, Werner Heisenberg, Max Born, Paul Dirac, and others."