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9 unusual facts about Hamiltonian


Complete set of commuting observables

Also, the Hamiltonian \hat{H} = -\frac{\hbar^2}{2\mu}\nabla^2 - \frac{Ze^2}{r} is a function of r only and has rotational invariance, where \mu is the reduced mass of the system.

Ermakov–Lewis invariant

Many quantum mechanical Hamiltonians are time dependent.

This allows an easy form to express the solution of the Schrödinger equation for the time dependent Hamiltonian.

Good quantum number

In the case of the hydrogen atom (with the assumption that there is no spin-orbit coupling), the observables that commute with Hamiltonian are the orbital angular momentum, spin angular momentum, the sum of the spin angular momentum and orbital angular momentum, and the z components of the above angular momenta.

It implies that a physical quantity A is conserved if its Poisson Bracket with the Hamiltonian is zero and it does not depend on time explicitly.

If the spin orbit interaction is taken into account, we have to add an extra term in Hamiltonian which represents the magnetic dipole interaction energy.

Systems which can be labelled by good quantum numbers are actually eigenstates of the Hamiltonian.

If such operators commute with the Hamiltonian, then their expectation value remains constant with time.

Two-state quantum system

All observable physical quantities associated with this systems are 2 \times 2 Hermitian matrices, this means the Hamiltonian of the system is also a similar matrix.


ADM formalism

-- The first lead sentence should define what it is--> developed in 1959 by Richard Arnowitt, Stanley Deser and Charles W. Misner is a Hamiltonian formulation of general relativity.

De Broglie–Bohm theory

According to Peter R. Holland, in a wider Hamiltonian framework, theories can be formulated in which particles do act back on the wave function.

Dedekind group

In 1898 George Miller delineated the structure of a Hamiltonian group in terms of its order and that of its subgroups.

Exchange interaction

Because the Heisenberg Hamiltonian presumes the electrons involved in the exchange coupling are localized in the context of the Heitler–London, or valence bond (VB), theory of chemical bonding, it is an adequate model for explaining the magnetic properties of electrically insulating narrow-band ionic and covalent non-molecular solids where this picture of the bonding is reasonable.

Joseph Liouville

In mathematical physics, Liouville made two fundamental contributions: the Sturm–Liouville theory, which was joint work with Charles François Sturm, and is now a standard procedure to solve certain types of integral equations by developing into eigenfunctions, and the fact (also known as Liouville's theorem) that time evolution is measure preserving for a Hamiltonian system.

LCF notation

In combinatorial mathematics, LCF notation or LCF code is a notation devised by Joshua Lederberg, and extended by Coxeter and Frucht, for the representation of cubic graphs that are Hamiltonian.

Ménage problem

However, two Hamiltonian cycles are considered to be equivalent if they connect the same vertices in the same cyclic order regardless of the starting vertex, while in the ménage problem the starting position is considered significant: if, as in Alice's tea party, all the guests shift their positions by one seat, it is considered a different seating arrangement even though it is described by the same cycle.

Michael Struwe

His publications include the book Variational methods (Applications to nonlinear PDE and Hamiltonian systems) (Springer-Verlag, 1990), which was praised by Jürgen Jost as "very useful" with an "impressive range of often difficult examples".

Molecular Hamiltonian

The molecular Hamiltonian is a sum of several terms: its major terms are the kinetic energies of the electrons and the Coulomb (electrostatic) interactions between the two kinds of charged particles.

Nambu mechanics

In 1973, Yoichiro Nambu suggested a generalization involving Nambu-Poisson manifolds with more than one Hamiltonian.

Symplectomorphism

If the first Betti number of a connected symplectic manifold is zero, symplectic and Hamiltonian vector fields coincide, so the notions of Hamiltonian isotopy and symplectic isotopy of symplectomorphisms coincide.

Tight binding

This interaction Hamiltonian includes direct Coulomb interaction energy and exchange interaction energy between electrons.

Variational methods in general relativity

The most commonly used tools are Lagrangians and Hamiltonians and are used to derive the Einstein field equations.


see also