Quantum mechanics

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The study of the behavior of matter and energy at the scale of atoms and subatomic particles.

Wave-particle duality: The concept that particles can exhibit both wave-like and particle-like behaviors, depending on the situation.
Uncertainty principle: The principle that states that it is impossible to determine the exact position and momentum of a particle simultaneously.
Operators: Mathematical representations of physical observables, used to make predictions about a system’s behavior.
Schrödinger equation: The foundational equation of quantum mechanics, which describes how a quantum system evolves over time.
Quantum states: The wave functions that describe the probabilities of finding a particle in a specific position and/or with a specific momentum.
Superposition: The principle that states that a particle can be in a state that is a combination of two or more other possible states.
Entanglement: The phenomenon where the quantum states of two or more particles are linked in such a way that the state of one particle affects the state of the others, regardless of the distance between them.
Quantum states in three dimensions: A more advanced version of quantum states that describes particles moving in three-dimensional space.
Quantum measurements: The way in which quantum systems are observed and measured, which can have an impact on the behavior of the system.
Energy levels: The discrete energy values that a particle can occupy in a given system.
Harmonic oscillator: A physical system that oscillates around a central point, following a pattern described by the Schrödinger equation.
Hydrogen atom: An example of a quantum system that can be described using the Schrödinger equation, which is often used as a starting point for learning quantum mechanics.
Quantum tunneling: The phenomenon where particles can cross energy barriers that would be impassable in classical physics.
Dirac equation: A relativistic version of the Schrödinger equation that describes the behavior of particles moving at speeds close to the speed of light.
Quantum field theory: A more advanced version of quantum mechanics that describes particles as excitations of fields.
Quantum computing: A field that explores the use of quantum systems to perform computational tasks that are beyond the capabilities of classical computers.
- "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."