Difference between revisions of "Talk:849: Complex Conjugate"

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(...does not "remove" imaginary part...)
 
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Actually multiplying complex number (x + iy) by its complex conjugate (x - iy) does not "remove" imaginary part, but calculate square of absolute value of complex number, (x^2 + y^2).  BTW. in quantum physics the wavefunction is complex valued, and its absolute value is probability density (a real valued function). --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 00:57, 18 December 2012 (UTC)
 
Actually multiplying complex number (x + iy) by its complex conjugate (x - iy) does not "remove" imaginary part, but calculate square of absolute value of complex number, (x^2 + y^2).  BTW. in quantum physics the wavefunction is complex valued, and its absolute value is probability density (a real valued function). --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 00:57, 18 December 2012 (UTC)
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I got hit in the face with my complex conjugate and lost an eye. {{unsigned ip|108.162.238.114}}
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I procreated with my complex conjugate and lost myself. [[Special:Contributions/108.162.216.114|108.162.216.114]] 19:44, 12 August 2014 (UTC)
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(a+bi)*(a-bi)= a^2-b^2 not a^2+b^2
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[[Special:Contributions/108.162.218.142|108.162.218.142]] 15:48, 24 June 2015 (UTC)
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(a+b)*(a-b) = a^2 - b^2 . However (a+bi)*(a-bi) = a^2 + b^2 since i^2 = -1. {{unsigned ip|108.162.219.65}}
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I think that the moving to a title text is a joke about them kicking you out of the room [[Special:Contributions/173.245.50.65|173.245.50.65]] 20:54, 1 May 2016 (UTC)
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Is it relevant that when he performs the complex conjugate multiplication, we go from a 2d image of the board to a 1d image of the board? My thinking is, that complex numbers are often used to describe a set of coordinates in 2d space. {{unsigned ip|162.158.158.233|06:58, 14 January 2020}}
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:It might be a nice coincidence, or happened on purpose. However in my understanding and the usecases I've seen for example in electrical engineering, it was the other way round. Complex Numbers were used to describe something , e.g. phase shift, and then it could be visualized as coordinates where it was visible as a sinus-curve. (I Might be slightly wrong about the details here. It's been some time...) --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 07:18, 14 January 2020 (UTC)
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What's with that red text? Is that MML? [[User:Marethyu|⟨Winter is coming⟩ Marethyu]] ([[User talk:Marethyu|talk]]) 21:27, 5 May 2022 (UTC)
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Everyone immediately recognised how the product of a complex function with its conjugate "makes shit real" but I think there's another layer of comedy (in a sort of anti-joke way) where the complex conjugate of a real number (a+0i) is (a-0i) in other words the product of an entirely real-valued function and its complex conjugate would just be its square which is an anticlimactic turn on the joke. [[Special:Contributions/172.70.93.13|172.70.93.13]] 15:13, 31 August 2022 (UTC)

Latest revision as of 15:13, 31 August 2022

Actually multiplying complex number (x + iy) by its complex conjugate (x - iy) does not "remove" imaginary part, but calculate square of absolute value of complex number, (x^2 + y^2). BTW. in quantum physics the wavefunction is complex valued, and its absolute value is probability density (a real valued function). --JakubNarebski (talk) 00:57, 18 December 2012 (UTC)

I got hit in the face with my complex conjugate and lost an eye. 108.162.238.114 (talk) (please sign your comments with ~~~~)

I procreated with my complex conjugate and lost myself. 108.162.216.114 19:44, 12 August 2014 (UTC)

(a+bi)*(a-bi)= a^2-b^2 not a^2+b^2 108.162.218.142 15:48, 24 June 2015 (UTC)

(a+b)*(a-b) = a^2 - b^2 . However (a+bi)*(a-bi) = a^2 + b^2 since i^2 = -1. 108.162.219.65 (talk) (please sign your comments with ~~~~)

I think that the moving to a title text is a joke about them kicking you out of the room 173.245.50.65 20:54, 1 May 2016 (UTC)

Is it relevant that when he performs the complex conjugate multiplication, we go from a 2d image of the board to a 1d image of the board? My thinking is, that complex numbers are often used to describe a set of coordinates in 2d space. 162.158.158.233 (talk) 06:58, 14 January 2020 (please sign your comments with ~~~~)

It might be a nice coincidence, or happened on purpose. However in my understanding and the usecases I've seen for example in electrical engineering, it was the other way round. Complex Numbers were used to describe something , e.g. phase shift, and then it could be visualized as coordinates where it was visible as a sinus-curve. (I Might be slightly wrong about the details here. It's been some time...) --Lupo (talk) 07:18, 14 January 2020 (UTC)

What's with that red text? Is that MML? ⟨Winter is coming⟩ Marethyu (talk) 21:27, 5 May 2022 (UTC)

Everyone immediately recognised how the product of a complex function with its conjugate "makes shit real" but I think there's another layer of comedy (in a sort of anti-joke way) where the complex conjugate of a real number (a+0i) is (a-0i) in other words the product of an entirely real-valued function and its complex conjugate would just be its square which is an anticlimactic turn on the joke. 172.70.93.13 15:13, 31 August 2022 (UTC)