Recent content by Emilie.Jung

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    Metrics: Stationary & Rotating - Can They Coexist?

    So there isn't a contradiction there? If something is rotating, say earth, the east hemisphere could be at point x in space and after a few hours it will be at point x'. What do you say?? @Dale
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    Metrics: Stationary & Rotating - Can They Coexist?

    Can metrics be stationary and rotating at the same time? Doesn't stationary here means that the metric is time-independent. Thus, if a metric is time-indepedent how could it be rotating?
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    What does ##\delta F=0## mean?

    Why do, we, in susy deal with "classical" solutions and "classical" eom? So is susy a classical theory? Because in this https://www.physicsforums.com/threads/scalars-and-special-geometry.840811/ fzero mentioned something about "quantum" theory in his first comment on that post.
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    Unraveling the Metric Found in Special Relativity

    In special relativity, we can prove that the metric is -+++ for all observers and that is by making use out of lorentz invariance. Some on this forum say that it comes as a result of constancy of light and others say that Minkowski predated einstein in making that metric, which was confusing...
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    I Why can't Gravitational Accelerations vanish everywhere?

    @PeterDonis Pete, is it true that freely falling body have zero proper acceleration? (Your version of proper acceleration?)
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    I Why can't Gravitational Accelerations vanish everywhere?

    I am afraid I can't but use the terminology. Maybe my question is simply, is it okay to call the term involving ##\Gamma## an inertial acceleration and still use your previous answers to understand things? If not, what is the exact reason that drove the author to say that this term involving...
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    I Why can't Gravitational Accelerations vanish everywhere?

    @PeterDonis I am confused. I have to say. Then what happens to your answer here: How can this answer (that answered my question about why sum and OP's question what experience does this tell us) be translated after knowing that the book we're using means different things? Also, notice there...
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    I Why can't Gravitational Accelerations vanish everywhere?

    @PeterDonis , I ve read some place that when we are in Minkowski space we have##\frac{d^2}{d\tau^2}x(\tau)=0## and then we we do general coordinate transformation, we get ##\frac{d^2}{d\tau^2}x^{\mu}+\Gamma^{\mu}_{\nu\lambda}\frac{dx^{ni}}{d\tau}\frac{dx^{\lambda}}{d\tau}=0##, the author calls...
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    I Why can't Gravitational Accelerations vanish everywhere?

    @PeterDonis thanks very much for your answer. I understand your argument very nicely if I considered e.g. when you said " you can make "gravitational acceleration" vanish everywhere, globally, by choosing appropriate coordinates." is correct. However, I can't tell you that I know what you mean...
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    I Why can't Gravitational Accelerations vanish everywhere?

    @WannabeNewton I am also interested in the question asked, which is why sum? I didn't understand how the link you provided settles this?
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    What does ##\delta F=0## mean?

    Hello again, I have a question please @haushofer So, when you say , you mean the metric (boson) transforms into "0" which is the same thing as ##\psi_{\mu}## (fermion) because the solution above was ##\psi_{\mu}=0##. BUT, when you say , the fermion (##\psi_{\mu}##) transforms into what?Should...
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    What does ##\delta F=0## mean?

    Thanks a lot for your explanation @haushofer ! I have read it but still I have to reread it with more attention, and will then get back to you next year if I have any questions :p. However, I wanted to wish you a happy new year.:oldbiggrin:
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    What does ##\delta F=0## mean?

    @haushofer from what I read the answer is not quite precise and does not answer the questions samuelphysics is asking about. What he's asking is in short "What does it mean to have a preserved supersymmetry". He's practically asking what does it mean that local supersymmetry variations must...
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    Why do those two terms add here?

    @nrqed I want to ask you about this because @samuelphysics's last question got me a little confused. We say that a Hermitian manifold is one in which unmixed components of metric tensor vanish (##g_{\alpha\beta}=g_{\bar{\alpha}\bar{\beta}}=0##). Is that correct? So every Hermitian metric there...
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