Linked Questions

4
votes
2answers
3k views

Lagrangian mechanics vs Hamiltonian mechanics [duplicate]

First of all, what are the differences between these two: Lagrangian mechanics and Hamiltonian mechanics? And secondly, do I need to learn both in order to study quantum mechanics and quantum field ...
0
votes
0answers
345 views

What is the essence of Lagrangian/Hamiltonian mechanics? [duplicate]

I'm reading on the calculus of variations, and Hamiltonian mechanics is discussed there. However, I'm not a physicist, so I cannot very well place the concept of Hamiltonian Mechanics in perspective. ...
46
votes
7answers
12k views

Why not use the Lagrangian, instead of the Hamiltonian, in nonrelativistic QM?

Undergraduate classical mechanics introduces both Lagrangians and Hamiltonians, while undergrad quantum mechanics seems to only use the Hamiltonian. But particle physics, and more generally quantum ...
56
votes
7answers
56k views

What is the difference between Newtonian and Lagrangian mechanics in a nutshell?

What is Lagrangian mechanics, and what's the difference compared to Newtonian mechanics? I'm a mathematician/computer scientist, not a physicist, so I'm kind of looking for something like the ...
8
votes
3answers
12k views

Advantages of Lagrangian Mechanics over Newtonian Mechanics [closed]

Here, I'm going to pose a very serious list of doubts I have on Lagrangian Mechanics. Can we learn Lagrangian Mechanics without studying Newtonian Mechanics? Does Lagrangian help in solving problems ...
15
votes
2answers
12k views

What is the difference between configuration space and phase space?

What is the difference between configuration space and phase space? In particular, I notices that Lagrangians are defined over configuration space and Hamiltonians over phase space. Liouville's ...
7
votes
2answers
8k views

Differences between classical, analytical, rational and theoretical mechanics

Can you explain me what are the differences between the four following subjects? analytical mechanics rational mechanics classical mechanics theoretical mechanics
1
vote
0answers
839 views

Conceptual difference between Hamiltonian and Lagrangian formulation [duplicate]

What is the basic difference between Lagrangian formulation and Hamiltonian formulations of mechanics? Why do we have two formulations when we can work with Hamiltonian most of the times (in quantum ...
2
votes
0answers
606 views

Can you give example of some problems with solutions in each of Newtonian, Lagrangian and Hamiltonian method? [closed]

I am a student from information system and just want to know about classical mechanics. I know Newtonian mechanics from high school and I have read about Lagrangian and Hamiltonian mechanics in ...
-3
votes
3answers
128 views

$F = ma$ not applicable at atomic dimensions?

Is the following logic valid? $F = ma$ does not hold at atomic dimensions because it is a continuous function. But since we know from the Einstein-Plank relation $E = nh\nu$, energy is quantized and ...