Transition: Classical Mechanics to Quantum Mechanics

go quantum!
Messages
54
Reaction score
0
Imagine that I have a system that is described classically by a given Hamiltonian which is a function of a given set of parameters q and their canonical conjugate momenta p=\frac{\partial L}{\partial \dot{q}}.
Then, I will say that the quantum description of the same system is guided by setting the commutator [ tex ] [q_a,p_a]=i [ /tex ] because the Poisson bracket is [tex ]{q_a,p_a}=1[ /tex ].

This step is crucial and it is the cornerstone of the process of quantizing. I would like to ask if you know some motivations for this step. Do you understand it?

Thanks for you help!
 
Last edited:
Physics news on Phys.org
The motivation for replacing Poisson brackets by commutators is that it works for simple one-particle systems in Cartesian coordinates - {x, p} → [x, p].

Note, that this replacement is not the end of the story. Now that the Hamiltonian is given in terms of operators, you have to decide a consistent ordering for those operators.
 
Is that the only motivation? It can't be...
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In her YouTube video Bell’s Theorem Experiments on Entangled Photons, Dr. Fugate shows how polarization-entangled photons violate Bell’s inequality. In this Insight, I will use quantum information theory to explain why such entangled photon-polarization qubits violate the version of Bell’s inequality due to John Clauser, Michael Horne, Abner Shimony, and Richard Holt known as the...
Not an expert in QM. AFAIK, Schrödinger's equation is quite different from the classical wave equation. The former is an equation for the dynamics of the state of a (quantum?) system, the latter is an equation for the dynamics of a (classical) degree of freedom. As a matter of fact, Schrödinger's equation is first order in time derivatives, while the classical wave equation is second order. But, AFAIK, Schrödinger's equation is a wave equation; only its interpretation makes it non-classical...
I am not sure if this falls under classical physics or quantum physics or somewhere else (so feel free to put it in the right section), but is there any micro state of the universe one can think of which if evolved under the current laws of nature, inevitably results in outcomes such as a table levitating? That example is just a random one I decided to choose but I'm really asking about any event that would seem like a "miracle" to the ordinary person (i.e. any event that doesn't seem to...
Back
Top