Classical mechanics problem for a free particle

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The discussion focuses on a classical mechanics problem involving a free particle of mass m moving in one dimension. It outlines three main tasks: calculating the action I for a particle with initial velocity v0, determining the trajectory x(t) for a particle with a different initial velocity v1 and constant acceleration a, and finding the action I(v1) for this new trajectory. The problem emphasizes that the particle remains free with no potential energy, which affects the equations of motion. Additionally, it seeks to establish the relationship between the action and the path taken, specifically examining whether the path represents a maximum, minimum, or inflection point of I(v1). The discussion encourages participants to provide relevant equations and initial attempts at solutions.
becks1
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Summary: The initial problem states: Consider a free particle of mass m moving in one space dimension with velocity v0. Its
starting point is at x = x0 = 0 at time t = t0 = 0 and its end point is at x = x1 = v0t1
at time t = t1 > 0. and this info is to do the 3 problems written out.

a) Calculate the action I for this path.
b) Now suppose that the particle has the same initial and final points in space and
time, but now has an initial velocity v1 6= v0 and a nonzero constant acceleration
a. Find a as a function of v1 and give the trajectory x(t). Note that this is still
a free particle with no potential energy, so x(t) will not satisfy the equations of
motion.
c) Find the action I(v1) for this trajectory, Show that dI/dv1 = 0 for the path
which solves the equation of motion. Is this path a maximum, a minimum. or an
inflection point of I(v1)?
 
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@becks1, please give relevant equations and show some attempt at a solution.
 
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(a) The polarisation pattern is elliptical with maximum (1,1) and minimum (-1,-1), and anticlockwise in direction. (b) I know the solution is a quarter-wave plate oriented π/4, and half-wave plate at π/16, but don't understand how to reach there. I've obtained the polarisation vector (cos π/8, isin π/8) so far. I can't find much online guidance or textbook material working through this topic, so I'd appreciate any help I can get. Also, if anyone could let me know where I can get more...

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