Canonical quantization with constraints

mhill
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let be the Lagrangian (1/2)m( \dot x ^{2} + \dot y^{2}) - \lambda (x^{2}+y^{2}-R^{2})

with 'lambda' a Lagrange multiplier , and 'R' is the radius of an sphere.

basically , this would be the movement of a particle in 2-d with the constraint that the particle must move on an sphere of radius 'R' , my doubt is that i do not know how to quantizy it since p_{\lambda}=0
 
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mhill said:
let be the Lagrangian (1/2)m( \dot x ^{2} + \dot y^{2}) - \lambda (x^{2}+y^{2}-R^{2})

with 'lambda' a Lagrange multiplier , and 'R' is the radius of an sphere.

basically , this would be the movement of a particle in 2-d with the constraint that the particle must move on an sphere of radius 'R' , my doubt is that i do not know how to quantize it since p_{\lambda}=0
Have a look at the Wiki page for Dirac brackets and Dirac-Bergman quantization:
http://en.wikipedia.org/wiki/Dirac_bracket
It explains the essence of constrained quantization.

See also this paper:

R. Jackiw, "(Constrained) Quantization Without Tears", hep-th/9306075
 
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