Quantum mechanics

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Quantum mechanics is the foundation of modern physics and is used in computational physics to study the behavior of subatomic particles and materials.

The wave-particle duality: This is the concept that fundamental particles often exhibit both wave-like and particle-like behaviors.
The Schrodinger equation: This equation describes how the state of a quantum system evolves over time.
Quantum states and operators: Quantum states are represented by state vectors in a Hilbert space, while operators act on these state vectors and describe observables such as position or momentum.
Quantum superposition and entanglement: Quantum superposition is the phenomenon whereby a particle can exist in two or more states simultaneously, while entanglement is the correlation between the quantum states of two or more particles.
Uncertainty principle: This principle states that it is impossible to precisely determine both the position and momentum of a particle simultaneously.
Quantum measurement and collapse of the wavefunction: When a quantum system is measured, the probability distribution of its properties collapses to a single value.
Quantum harmonic oscillator: The harmonic oscillator is a simple model that has many applications in quantum mechanics.
Hydrogen atom: The hydrogen atom is the simplest atom and serves as a key example to understand the behavior of electrons in atoms.
Time-independent perturbation theory: This technique is used to calculate the properties of a system that has been perturbed from its initial state.
Time-dependent perturbation theory: This technique is used to study changes to a quantum system over time due to a perturbation.
Scattering theory: This is the study of how particles scatter off one another and is important for understanding processes such as nuclear reactions.
Tunneling: Tunneling is the phenomenon where a particle can pass through a barrier even if its energy is less than the height of the barrier.
Relativistic quantum mechanics: This is the study of how quantum mechanics can be reconciled with relativity and is necessary for understanding the behavior of particles traveling at high speeds.
Many-particle systems: The behavior of a system of many interacting particles is crucial in fields such as condensed matter physics.
Quantum algorithms: Quantum computers use the strange properties of quantum mechanics to perform certain calculations more efficiently than classical computers.
Quantum Computing: It involves using quantum bits or qubits to process information and solve complex mathematical problems which are beyond the scope of classical computers.
Quantum Cryptography: It is the study of the security of communication through quantum means, like quantum key distribution, which enables the encoding and decoding of messages on the basis of quantum-mechanical principles.
Quantum Information Theory: It deals with the transmission and processing of information using quantum systems to achieve greater efficiency and security.
Quantum Field Theory: Describes the behavior of quantum fields, which are the fundamental entities that underlie all particles and fields in the universe, and used to describe high-energy particle interactions.
Quantum Optics: Focuses on the behavior of light and its interaction with matter at the quantum level, relevant for the design of new materials, communication systems, laser technologies, etc.
Quantum Simulation: It involves simulating the behavior of complex physical systems or chemical reactions, which are very difficult, if not impossible, to simulate on classical computers.
Quantum Control: The study of how to manipulate the dynamics of quantum systems, e.g., to minimize energy losses or to maximize the efficiency of quantum machines.
Quantum Metrology: The precision measurement of physical quantities, such as time, frequency, distance, etc., using quantum systems, is used in a wide range of applications, e.g., navigation, synchronization, and atomic clocks.
- "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."