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PrathameshR
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In a lecture on introductory quantum mechanics the teacher said that Heisenberg uncertainty principle is applicable only to canonically conjugate physical quantities. What are these quantities?
I do not know what poisson bracket is[emoji20] [emoji29]hilbert2 said:Quantities A and B are canonically conjugate if their classical mechanical Poisson bracket is equal to unity. The most simple example is the x-coordinate of a particle and the corresponding momentum ##p_x##.
PrathameshR said:I do not know what poisson bracket is[emoji20] [emoji29]
vanhees71 said:How can one do QT without knowing about Poisson brackets? I'm puzzled!
I Started reading this book. Finding it really interesting and lucid. Thank you for recommending this book.hilbert2 said:This is also good, but it can be a bit difficult for a beginner: http://www.damtp.cam.ac.uk/user/tong/dynamics/clas.pdf .
PrathameshR said:I have completed 3 courses on classical mechanics but never came across terms like poisson bracket, Hamiltonian etc.
weirdoguy said:How can one take 3 courses on classical mechanics without learning about Poisson brackets and Hamiltonians, that's a question
Canonically conjugate quantities are a pair of physical quantities that are related by a mathematical operation known as a "canonical transformation". These quantities have a special mathematical relationship that allows them to be used together to describe a physical system.
In physics, canonically conjugate quantities play a crucial role in the formulation of Hamiltonian mechanics, which is a mathematical framework used to describe the dynamics of physical systems. They also have important applications in quantum mechanics and statistical mechanics.
Some examples of canonically conjugate quantities include position and momentum, energy and time, and electric field and magnetic induction. These pairs of quantities are related by a canonical transformation, which allows them to be used together in physical equations.
The Heisenberg uncertainty principle states that the precision with which certain pairs of physical quantities can be measured is limited by a fundamental uncertainty. This uncertainty is related to the non-commutativity of canonically conjugate quantities, such as position and momentum, in quantum mechanics.
No, canonically conjugate quantities can only be used to describe systems that exhibit certain symmetries and can be described using Hamiltonian mechanics. For more complex systems, other mathematical frameworks may be necessary to describe the dynamics.