Help


[permalink] [id link]
+
Page "Schrödinger equation" ¶ 55
from Wikipedia
Edit
Promote Demote Fragment Fix

Some Related Sentences

Schrödinger and though
Note that this equation only holds when the density operator is taken to be in the Schrödinger picture, even though this equation seems at first look to emulate the Heisenberg equation of motion in the Heisenberg picture, with a crucial sign difference:
The process of quantum decoherence explains in terms of the Schrödinger equation how certain components of the universal wave function become irreversibly dynamically independent of one another ( separate worlds – even though there is but one quantum world that does not split ).
Born was awarded half of the 1954 Nobel Prize in physics for this understanding, though it was vigorously contested at the time by the original physicists working on the theory, such as Schrödinger and Einstein.
Even though the Schrödinger equation was developed two years later, Wentzel, Kramers, and Brillouin were apparently unaware of this earlier work, so Jeffreys is often neglected credit.

Schrödinger and always
In the formulation of the De Broglie – Bohm theory, there is only a wave function for the entire universe ( which always evolves by the Schrödinger equation ).
Unlike the universal wave function, the conditional wave function of a subsystem does not always evolve by the Schrödinger equation, but in many situations it does.
The fact that the conditional wave function of a subsystem does not always evolve by the Schrödinger equation is related to the fact that the usual collapse rule of Standard Quantum Theory emerges from the Bohmian formalism when one considers conditional wave functions of subsystems.
The advent of quantum decoherence theory allowed alternative approaches ( such as the Everett many-worlds interpretation and consistent histories ), wherein the Schrödinger equation is always satisfied, and wavefunction collapse should be explained as a consequence of the Schrödinger equation.
Everett claims that the universe has a single quantum state, which he called the universal wavefunction, that always evolves according to the Schrödinger equation or some relativistic equivalent ; now the measurement problem suggests the universal wavefunction will be in a superposition corresponding to many different definite macroscopic realms (" macrorealms "); that one can recover the subjective appearance of a definite macrorealm by postulating that all the various definite macrorealms are actual – it seems to each observer that " we just happen to be in one rather than the others " because " we " are in all of them, but each are mutually unobservable.
The wavefunction in quantum mechanics evolves deterministically according to the Schrödinger equation as a linear superposition of different states, but actual measurements always find the physical system in a definite state.
The book concludes with the idea which he claims Schrödinger supported, that the sum total of all minds is one, and that individual brains are best understood as local receivers, of an overall transmission which is always everywhere.

Schrödinger and statistical
Once the Schrödinger equation was given a probabilistic interpretation, Ehrenfest showed that Newton's laws hold on average: the quantum statistical expectation value of the position and momentum obey Newton's laws.
" (“ Does Schrödinger ’ s wave mechanics determine the motion of a system completely or only in the statistical sense ?”).
( Examples are the Schrödinger wave equation of quantum mechanics, and the Maxwell-Boltzmann distribution of statistical mechanics.
Other techniques include the path integration that draws on the analogy between statistical physics and quantum mechanics ( for example, the Fokker-Planck equation can be transformed into the Schrödinger equation by rescaling a few variables ) or by writing down ordinary differential equations for the statistical moments of the probability distribution function.

Schrödinger and probabilistic
Schrödinger himself initially did not understand the fundamental probabilistic nature of quantum mechanics, as he thought that the absolute square of the wave function of an electron should be interpreted as the charge density of an object smeared out over an extended, possibly infinite, volume of space.
In fact, the wave aspect of matter was formalized by a wavefunction defined by the Schrödinger equation, which is a pure mathematical entity having a probabilistic interpretation, without the support of real physical elements.
In June 1926, Max Born published a paper, " Zur Quantenmechanik der Stoßvorgänge " (" Quantum Mechanics of Collision Phenomena ") in the scientific journal Zeitschrift für Physik, in which he was the first to clearly enunciate the probabilistic interpretation of the quantum wavefunction, which had been introduced by Erwin Schrödinger earlier in the year.
The experimental data show that quantum-mechanical probability does not cover the entire probabilistic nature of the microworld and that God plays dice not exactly the way prescribed by Schrödinger.
The QSHJE can be demonstrated to imply the Schrödinger equation with square-summability of the wave function, and thus quantization of energy, due to continuity conditions of the quantum potential, without any assumption on the probabilistic interpretation of the wave function.

Schrödinger and approach
As these methods are pushed to the limit, they approach the exact solution of the non-relativistic Schrödinger equation.
Once the electronic and nuclear variables are separated ( within the Born – Oppenheimer representation ), in the time-dependent approach, the wave packet corresponding to the nuclear degrees of freedom is propagated via the time evolution operator ( physics ) associated to the time-dependent Schrödinger equation ( for the full molecular Hamiltonian ).
In the complementary energy-dependent approach, the time-independent Schrödinger equation is solved using the scattering theory formalism.
Within the framework of the approach a theory was proposed in which the physical vacuum is conjectured to be the quantum Bose liquid whose ground-state wavefunction is described by the logarithmic Schrödinger equation.
In the Schrödinger approach classical behavior is not clear because the waves spread out as they move.
" This is a major departure from the approach of Newton, Einstein and Schrödinger, all of whom expressed their theories in terms of deterministic equations.
" This is a major departure from the approach of Newton, Einstein and Schrödinger, all of whom expressed their theories in terms of deterministic equations.
The outcome of implementation of this idea is an alternative path integral approach to quantum mechanics, which results in a new fundamental quantum equation-the fractional Schrödinger equation.
Erwin Schrödinger discussed at length the Stark effect in his third paper on quantum theory ( in which he introduced his perturbation theory ), once in the manner of the 1916 work of Epstein ( but generalized from the old to the new quantum theory ) and once by his ( first-order ) perturbation approach.
Inspired by Einstein's approach to a unified field theory and Eddington's idea of the affine connection as the sole basis for differential geometric structure for space-time, Erwin Schrödinger from 1940 to 1951 thoroughly investigated pure-affine formulations of generalized gravitational theory.
Oddly enough, this approach is analogous to the way Erwin Schrödinger first solved the hydrogen atom.
A well known approach involves recasting the molecular Schrödinger equation into a set of coupled eigenvalue equations.
Full configuration interaction ( or full CI ) is a linear variational approach which provides numerically exact solutions ( within the infinitely flexible complete basis set ) to the electronic time-independent, non-relativistic Schrödinger equation.

Schrödinger and with
Atomic orbitals can be the hydrogen-like " orbitals " which are exact solutions to the Schrödinger equation for a hydrogen-like " atom " ( i. e., an atom with one electron ).
For example, in the Schrödinger picture, there is a linear operator U with the property that if an electron is in state right now, then in one minute it will be in the state, the same U for every possible.
Swiss physicist Felix Bloch provided a wave function solution to the Schrödinger equation with a periodic potential, called the Bloch wave.
Computational chemists often attempt to solve the non-relativistic Schrödinger equation, with relativistic corrections added, although some progress has been made in solving the fully relativistic Dirac equation.
The total energy is determined by approximate solutions of the time-dependent Schrödinger equation, usually with no relativistic terms included, and by making use of the Born – Oppenheimer approximation, which allows for the separation of electronic and nuclear motions, thereby simplifying the Schrödinger equation.
The programs used in computational chemistry are based on many different quantum-chemical methods that solve the molecular Schrödinger equation associated with the molecular Hamiltonian.
Complex-crater morphology on rocky planets appears to follow a regular sequence with increasing size: small complex craters with a central topographic peak are called central peak craters, for example Tycho ; intermediate-sized craters, in which the central peak is replaced by a ring of peaks, are called peak-ring craters, for example Schrödinger ; and the largest craters contain multiple concentric topographic rings, and are called multi-ringed basins, for example Orientale.
Provided the theory is linear with respect to the wavefunction, the exact form of the quantum dynamics modelled, be it the non-relativistic Schrödinger equation, relativistic quantum field theory or some form of quantum gravity or string theory, does not alter the validity of MWI since MWI is a metatheory applicable to all linear quantum theories, and there is no experimental evidence for any non-linearity of the wavefunction in physics.
For example, as the only neutral atom with an analytic solution to the Schrödinger equation, the study of the energetics and bonding of the hydrogen atom played a key role in the development of quantum mechanics.
Finally, some of the originators of quantum theory ( notably Einstein and Schrödinger ) were unhappy with what they thought were the philosophical implications of quantum mechanics.
Moreover, even if in the Schrödinger picture the Hamiltonian does not depend on time, e. g., in the interaction picture it does, at least, if V does not commute with, since
File: Schrodinger. jpg | Erwin Schrödinger ( 1887-1961 ): formulated the Schrödinger equation in 1926 describing how the quantum state of a physical system changes with time, awarded the Nobel Prize in Physics in 1933, two years later proposed the thought experiment known as Schrödinger's cat
File: Dirac 4. jpg | Paul Dirac ( 1902-1984 ): made fundamental contributions to the early development of quantum mechanics and quantum electrodynamics, formulated the Dirac equation describing the behavior of fermions, predicted the existence of antimatter, shared the1933 Nobel Prize in Physics with Erwin Schrödinger,
The Schrödinger equation, applied to the aforementioned example of the free particle, predicts that the center of a wave packet will move through space at a constant velocity ( like a classical particle with no forces acting on it ).
Early attempts to merge quantum mechanics with special relativity involved the replacement of the Schrödinger equation with a covariant equation such as the Klein-Gordon equation or the Dirac equation.
The first step in solving a quantum chemical problem is usually solving the Schrödinger equation ( or Dirac equation in relativistic quantum chemistry ) with the electronic molecular Hamiltonian.
A further step can consist of solving the Schrödinger equation with the total molecular Hamiltonian in order to study the motion of molecules.
Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the theory of relativity.
In 1925 and 1927, Mulliken traveled to Europe, working with outstanding spectroscopists and quantum theorists such as Erwin Schrödinger, Paul A. M. Dirac, Werner Heisenberg, Louis de Broglie, Max Born, and Walther Bothe ( all of whom eventually received Nobel Prizes ) and Friedrich Hund, who was at the time Born's assistant.
Up until that time, attempts to make the old quantum theory of the atom compatible with the theory of relativity, attempts based on discretizing the angular momentum stored in the electron's possibly non-circular orbit of the atomic nucleus, had failed-and the new quantum mechanics of Heisenberg, Pauli, Jordan, Schrödinger, and Dirac himself had not developed sufficiently to treat this problem.
with the conservation of probability current and density following from the Schrödinger equation:

0.271 seconds.