What physical systems exhibit nonseparable Hamiltonians in classical mechanics?

  • Thread starter Q_Goest
  • Start date
  • Tags
    Hamiltonian
In summary, the conversation discusses the concept of nonseparability in classical mechanics, specifically in relation to the use of direct sum and tensor product operations in defining the states of a composite system. The presence of nonseparable Hamiltonians in classical mechanics, resulting from nonlinear terms in the equations of motion, may suggest a potential emergence in classical systems. The example of chaotic behavior in classical systems is also mentioned. Kronz's paper "Emergence and Quantum Mechanics" is referenced for further reading. The conversation ends with a request for an example of a physical system with a nonseparable Hamiltonian and a question about the measurable characteristics and equations involved.
  • #1
Q_Goest
Science Advisor
Homework Helper
Gold Member
3,012
42
I’m trying to decipher this particular passage from a paper.

Because the direct sum is used in classical mechanics to define the states of a composite system in terms of its components, rather than the tensor product operation as in quantum mechanics, there are no nonseparable states in classical mechanics. There are nonseparable Hamiltonians in classical mechanics – the Hamiltonian corresponds to the total energy of the system and is related to the time evolution of the system. This type of nonseparability is the result of nonlinear terms in the equations of motion. Perhaps a kind of emergence can be associated with it. Some measure of plausibility is given to this claim since a classical system can exhibit chaotic behavior only if its Hamiltonian is nonseparable.
Ref: FM Kronz, JT Tiehen - Philosophy of Science, 2002 “Emergence and Quantum Mechanics”

Can you provide an example of a physical system which corresponds to a classical system with a nonseparable Hamiltonian (ex: the Milky Way galaxy, flow of water)? What measurable characteristics (ex: motion or potential/kinetic energy of planets, local velocity of fluid) is Kronz referring to when he claims such things are nonseparable? What equations are not separable and what are the equations describing?
 
Physics news on Phys.org
  • #2
@Q_Goest did you ever figure this out?
 

1. What is a Nonseparable Hamiltonian?

A Nonseparable Hamiltonian is a mathematical function used to describe the dynamics of a physical system in classical mechanics. It consists of two components: kinetic energy and potential energy, and is used to determine the equations of motion for a system.

2. How is a Nonseparable Hamiltonian different from a Separable Hamiltonian?

A Separable Hamiltonian has the property that the kinetic and potential energies can be expressed as separate functions of position and momentum. In contrast, a Nonseparable Hamiltonian does not have this property, making it more complex to solve and analyze.

3. What are the applications of Nonseparable Hamiltonians?

Nonseparable Hamiltonians have a wide range of applications in physics, including celestial mechanics, quantum mechanics, and statistical mechanics. They are also used in fields such as optics, plasma physics, and fluid dynamics to study the behavior of complex systems.

4. How are Nonseparable Hamiltonians solved?

Nonseparable Hamiltonians are typically solved using numerical methods, such as numerical integration or perturbation theory. These methods involve breaking down the complex equations into smaller, more manageable parts and solving them iteratively to approximate the solution.

5. What are the limitations of using Nonseparable Hamiltonians?

One limitation of using Nonseparable Hamiltonians is that they are often difficult to solve analytically, which can limit the understanding of a system's behavior. Additionally, Nonseparable Hamiltonians may not accurately describe certain physical systems, requiring the use of more complex mathematical models.

Similar threads

  • Other Physics Topics
Replies
2
Views
13K
  • Quantum Physics
Replies
10
Views
2K
  • Quantum Interpretations and Foundations
11
Replies
376
Views
10K
  • Other Physics Topics
Replies
1
Views
1K
Replies
20
Views
8K
Replies
6
Views
2K
Replies
8
Views
2K
Replies
14
Views
6K
Replies
3
Views
697
  • Quantum Physics
Replies
1
Views
2K
Back
Top