Recent content by wasi-uz-zaman

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    Graduate Lagrangian density for the spinor fields

    i am new in QFT , wants to write lagrangain density - how should i proceed , do i strat from Dirac equation and its adjoint - if so than i have seen derivation of Dirac equation from the Dirac lagrangian density-here confusion lies- so my point is seeing symmetries alone how can we model...
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    Graduate Lagrangian density for the spinor fields

    hi, i have seen lagrangian density for spin 0 , spin 1/2, spin 1 , but i am not getting from where these langrangian densities comes in at a first place. kindly give me the hint. thanks
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    High School Why are SU(3), SU(2) and U(1) groups used in the Standard Model?

    hi, i have studied Standard Model for particle physics - at present it is described by three groups - i have studied - these groups but could not establish what particular feature suggest of these group to be used to describe SM. Thanks
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    Graduate Solving nonlinear singular differential equations

    hi, i am going through differential equations which are nonlinear and singular - like Lane-Emden equation etc. my question is how to tackle singularity - while coding. regards
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    Undergrad Why Is a Differential Equation Called Nonlinear?

    hi, i am working on nonlinear differential equation- i know rules which decide the equation to be nonlinear - but i want an answer by which i can satisfy a lay man that why the word nonlinear is used. it is easy to explain nonlinearity in case of simple equation i.e when output is not...
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    Graduate Measurement from Feynman diagram

    hi, can anyone please give me the list of measurement we can do ON Feynman diagram? Like , branching ratio, cross-section etc
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    Python Evolve Computing: Solve Nonlinear Singular DEs

    hi, i am working on Evolutionary computing, i have solved non-linear singular differential equation through genetic algorithm, but now i am interested to solve it through other techniques of EC as well, like genetic programming , evolutionary strategies, evolutioanry programming etc regards wasi
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    Graduate Solve Troesch's Equation: Numerical Technique & Derivation

    hi, i am going to solve Troesch's equation u′′(x) = λ sinh(λu(x)) by numerical technique, but i couldn't find the derivation of it- kindly anyone knows its derivation or details of variable used. regards wasi
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    Graduate How do heavier nuclei maintain stability despite requiring energy for fusion?

    I understand overall decrease in potential energy of Lighter nuclei releases energy on Fusion- but for heavier nuclei - energy is required- means overall potential energy is not decreased - than how these heavier nuclei sustained their stability.
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    Graduate Solve Stellar Structure with Lane-Emden Equation

    Thanks a lot , it indeed clear my query to a great extent.
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    Graduate Solve Stellar Structure with Lane-Emden Equation

    HI, I have a question can Lane-Emden equation be use in SSM( standard stellar model) and overall for the study of stellar structure in todays latest research. thanks
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    Help understanding genetic algorithms please

    HELLO, i have started working on Genetic Algorithm , i have studied evloution of fitness function, but i really could not get it. please help me in this regard wasi
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    Graduate Why is Picard Iteration Named Fixed Point Iteration?

    hi, i want to figure out why it is named as fixed point iteration.
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    Undergrad How can we identify non-linear singular differential equation

    i am doing research to make criteria by which i can identify easily linear and non-linear and also identify its singular or not by doing simple test.please help me in this regard.
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    Undergrad How Do Metals Affect Electric Fields and EM Waves?

    thanks that helps , actually i am figuring out why EM waves cannot pass through metal interface. wasi