8. Translation Symmetry

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  • Опубликовано: 25 янв 2025

Комментарии • 13

  • @berketozlu
    @berketozlu 4 года назад +5

    Damn, this is so beautiful. When the something as usual as waves are just infinite combinations of oscillations with fixed ends. When you can prove it with math, it just blows your mind.

  • @BlueRaja
    @BlueRaja 3 года назад +5

    Shouldn't the equation for 'k' at 48:05 include 'a'?
    sin(x) = 0 happens when x = nπ, so sin[(N+1)ka] happens when (N+1)ka = nπ. Solving for k gives
    k = nπ/[a(N+1)]
    Also, (assuming 'a' is 1) shouldn't k range from 1 to 2N+1? Since sin(x) hits 0 again at π, but it doesn't start repeating itself until 2π

    • @ashutoshpanigrahy7326
      @ashutoshpanigrahy7326 3 года назад +1

      k=2*pi/lambda and lambda||min=2*a so n

    • @ey3796
      @ey3796 2 года назад

      @@ashutoshpanigrahy7326 I am not able to understand your comment, can you please explain it again? Thanks

    • @srinivassandhyala1591
      @srinivassandhyala1591 2 года назад

      a is just a constant so I think there is no problem in answer because 2 sin (0) and sin(0) are same

    • @NN-lt3kh
      @NN-lt3kh Год назад +1

      There should definitely be an a, I think he just forgot it. Otherwise the boundary condition would not hold.

  • @franciscoeduardo198
    @franciscoeduardo198 6 лет назад +5

    Why is omega^2*A= A_tt? Aren't newtons laws complete derivativea? Why is it partial? Isn't A constant in the first coupled equations, so that the derivative only applies to the exponencial term? Why does the derivative operator apply now to A, even going from a total derivative to a partial one?

    • @reevise
      @reevise 2 года назад

      I think instead of A there should be wave function.

    • @jlynem
      @jlynem 2 года назад

      Making the system continuous means A is now a continuous function of x. To describe the amplitude of the system at any place at any time you need to describe it in terms of both x and t, so we are in multivariable calculus with the partial derivatives. That's the wave function!

  • @subbaiyanshanmugathevar2193
    @subbaiyanshanmugathevar2193 6 лет назад +3

    good job.i have exam day affter tommoro

  • @goulchat1
    @goulchat1 Год назад

  • @omarmaswadeh5434
    @omarmaswadeh5434 6 лет назад

    I didn't like the approximations, it is too stilted!