Griffiths Quantum Mechanics Problem 1.5: Normalization and Expectation Values of Given Wavefunction

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  • เผยแพร่เมื่อ 20 ม.ค. 2025

ความคิดเห็น • 47

  • @brytanniparrett
    @brytanniparrett 2 ปีที่แล้ว +1

    Dam. What an absolutely brilliant idea for asmr.

  • @IffyProjects
    @IffyProjects 6 ปีที่แล้ว +4

    great video. Really helped me with my physics assignment :)

  • @meditationtube7572
    @meditationtube7572 7 ปีที่แล้ว +1

    where does the 2 multiplying the A at 03:12 come from? please help

    • @riteshkumarsingh6473
      @riteshkumarsingh6473 6 ปีที่แล้ว +2

      Its the property of integral

    • @kashyapsandeepmusic
      @kashyapsandeepmusic 5 ปีที่แล้ว

      conjugate of i cancels each other ( conjugate of e^-iwt would be e^iwt .. so e^-iwt+iwt=e^0=1)

  • @tashmotsi7540
    @tashmotsi7540 6 ปีที่แล้ว +2

    how does one get rid of the absolute x. always multiply by 2?

    • @frasergascoigne7442
      @frasergascoigne7442 6 ปีที่แล้ว

      The function is reflected in the y axis. The function is symmetrical due to the modulus x so the -inf to 0 is the same as the 0 to inf so you can just do 2* 0t to inf

    • @bilawalilyas1755
      @bilawalilyas1755 6 ปีที่แล้ว

      I can’t understand 2A

    • @uhuihiuhuihi
      @uhuihiuhuihi 5 ปีที่แล้ว +3

      Basically the function has the interval:
      e^-k|x| = { e^kx for x < 0
      { e^-kx for x > 0
      This implies the function is symmetrical about the y-axis, so the area under the curve for the interval (-infinity to 0) is equal to the area under the curve for the interval (0 to +infinity) -- you can graph this using an arbitrary number for k if you want visual proof.
      Thus, you can just integrate over one interval and multiply it by 2 and get the same answer.

    • @Barfriedrich12
      @Barfriedrich12 4 ปีที่แล้ว

      If the function is odd.

  • @eugeneng2574
    @eugeneng2574 5 ปีที่แล้ว

    Why does the lower boundary and upper boundary changes from infinity ♾ to 0 and positive infinite? And why is it multiplied by 2 after the change occur?

    • @utsavm4862
      @utsavm4862 5 ปีที่แล้ว

      Check out even and odd functions, you'll get it.

  • @ctcy7580
    @ctcy7580 4 ปีที่แล้ว

    Why didn't conjugate cancel e^(-λ|x|) at the start?

    • @sorzin2289
      @sorzin2289 3 ปีที่แล้ว

      I believe only the imaginary part of the function is conjugated

  • @omarmedellin8244
    @omarmedellin8244 6 ปีที่แล้ว +4

    why e^-i2wt disappears?

    • @kashyapsandeepmusic
      @kashyapsandeepmusic 5 ปีที่แล้ว +6

      conjugate of i cancels each other ( conjugate of e^-iwt would be e^iwt .. so e^-iwt+iwt=e^0=1)

  • @kevinkameswara928
    @kevinkameswara928 6 ปีที่แล้ว +2

    why does the e^i2wt drop out?

    • @uhuihiuhuihi
      @uhuihiuhuihi 5 ปีที่แล้ว +3

      When you multiply psi by its complex conjugate that part becomes e^-iwt*e^iwt = e^-iwt+iwt = e^0 = 1. It doesn't go anywhere, it just evaluates to 1 so you don't need to write it since multiplying by 1 doesn't change anything.

    • @rafaelgomesUmbermash
      @rafaelgomesUmbermash 5 ปีที่แล้ว

      @@uhuihiuhuihi
      thanks, helps a lot!!

  • @kaanguzsoy8651
    @kaanguzsoy8651 5 ปีที่แล้ว

    How to we get X eqaution? 6:00

    • @kaanguzsoy8651
      @kaanguzsoy8651 5 ปีที่แล้ว

      expectation value equation *

  • @adamfattal6382
    @adamfattal6382 7 ปีที่แล้ว +10

    This is an amazing video, which helped a lot! But the only problem is that you seem nervous and the sound's too low, but other than that, good job.

  • @tauhid9983
    @tauhid9983 5 ปีที่แล้ว +1

    Do you need to learn about eigenvectors and eigenvalues for this problems

  • @peeweeman34
    @peeweeman34 5 ปีที่แล้ว +2

    The people commenting don’t realize half the purpose of his videos, it’s right in his channel name. Look up ASMR.

  • @indramishra3886
    @indramishra3886 5 ปีที่แล้ว

    How you remove -iwt

    • @matrixate
      @matrixate 5 ปีที่แล้ว

      When you multiply by the conjugate, the sign of i switches and then it's just addition which cancels out the terms in the exponents. Look at properties of exponents to see how that works.

  • @e-lexusthornton6331
    @e-lexusthornton6331 5 ปีที่แล้ว

    Right at the end shouldn't p-out equal e^-(2/√2)?

    • @TakuyaDan
      @TakuyaDan 5 ปีที่แล้ว

      2/sqrt(2) is by definition the same as sqrt(2)

  • @lucafaraday007
    @lucafaraday007 6 ปีที่แล้ว

    Muito bom! salvador da Pátria! Tava precisando dessa resolução! Obrigado! Thank's!

  • @mainakchakravorti6810
    @mainakchakravorti6810 7 ปีที่แล้ว

    please increase the sound

  • @indramishra3886
    @indramishra3886 5 ปีที่แล้ว

    Terms are not explain

  • @mkminerals12343
    @mkminerals12343 8 ปีที่แล้ว

    its good but showing on the screen is less,its audio voice is too low

  • @PB-cb7ht
    @PB-cb7ht 6 ปีที่แล้ว +1

    This would have been a perfect video if you didnt mumble. Still helped me none the less

  • @alkamehra2406
    @alkamehra2406 4 ปีที่แล้ว

    Steps not explained and volume is very low
    And video is also very slow

  • @anantgalge4470
    @anantgalge4470 7 ปีที่แล้ว

    you seem to be doubtful at some steps

  • @svnithelp7920
    @svnithelp7920 6 ปีที่แล้ว

    explain is fast and noise willbe enable to listen

  • @AliAsghar-wo6ne
    @AliAsghar-wo6ne 4 ปีที่แล้ว

    Your sound is very low

    • @Palisade5810
      @Palisade5810 3 ปีที่แล้ว

      It's ASMR,it's supposed to be low.

  • @usmanawan477
    @usmanawan477 4 ปีที่แล้ว

    Plz speak loudly

  • @00morte
    @00morte 7 ปีที่แล้ว +1

    speak up...

  • @Dyslexic-Artist-Theory-on-Time
    @Dyslexic-Artist-Theory-on-Time 6 ปีที่แล้ว

    Do you think it is logical that if the future is unfolding relative to the atoms, if we look down at the individual atoms we will find probability? This is an invitation to see a theory on the nature of time! In this theory we have an emergent uncertain future continuously coming into existence relative to the spontaneous absorption and emission of photon energy. Within such a process the wave particle duality of light and matter in the form of electrons is forming a blank canvas that we can interact with forming the possible into the actual! The future is unfolding with each photon electron coupling or dipole moment relative to the atoms of the periodic table and the individual wavelengths of the electromagnetic spectrum. As part of a universal process of energy exchange that forms the ever changing world of our everyday life the ‘past’ has gone forever. At the smallest scale of this process the ‘past’ is represented by anti-matter annihilation with the symmetry between matter and anti-matter representing the symmetry between the future and the past as the future unfolds photon by photon. In such a theory the mathematics of quantum mechanics represents the physics of ‘time’ with the classical physics of Newton representing processes over a period of time, as in Newton’s differential equations. In my videos I explain how this process is relative to temperature and the phase changes of matter.

  • @sertacsertac2650
    @sertacsertac2650 6 ปีที่แล้ว

    Quantum with the sex voice

  • @matrixate
    @matrixate 5 ปีที่แล้ว

    Bro...you can't mumble on something like this. Is that how you were taught? C'mon bro. Practice explaining this or teaching it to a couple of people before putting yourself out there, trying to explain something that you yourself are learning.

  • @rohanmathew5728
    @rohanmathew5728 6 ปีที่แล้ว

    Very shabby work ..!! Lacks adequate explanation. It would have been better if this video wasn't made, because it didn't help a bit.