Recent content by Arny_Toynbee

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    Undergrad Square of the difference of four-vectors

    Sorry, sign errors in which equation? By the way, the way it is derived in the link is not necessarily consistent. What is the correct answer (of the alternatives posted)?
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    Undergrad Square of the difference of four-vectors

    The link provided may be using a different convention. Until now, I have provided all the algebra and the question. It was suggested that "...realize that the link you provided...has the solution...?" The original question has two alternatives, and it is useful to see what the forum members come...
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    Undergrad Square of the difference of four-vectors

    Actually, you may not realize, there might be a surprise on the way!
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    Undergrad Square of the difference of four-vectors

    How would you write out (p3 - p4)? There's a bit of subtlety here, and not guessing, see for e.g. Equation 46.29 here
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    Undergrad Square of the difference of four-vectors

    The question is (p3 - p4)^2 - whether it is (wp3-wp4)2 + (p3 - p4)2 or is it (wp3+wp4)2 - (p3 + p4)2 Hmmmmmm...what do I get?
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    Undergrad Square of the difference of four-vectors

    p3.p4 = = p30 p40 - p3.p4
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    Undergrad Square of the difference of four-vectors

    p3.p4 = (p30, p3) . (p40, p4) and p30= wp3 etc.
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    Undergrad Square of the difference of four-vectors

    What is the correct way to expand (p3-p4)2 where p3 and p4 are 4-vectors, with metric gmu nu=diag[1,-1,-1,-1], p = [wp, p], where p is 3-vector, and wp= (p2+m2)(1/2)
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    Exploring the World of Physics: A Student and Hobbyist's Guide on PF

    Physics student and hobbyist