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    News Greece, Italy and the Euro

    The glaring omission in that article is however the same statistic for the UK, with aggregate debt at 469%. Even after gratuitously subtracting the contribution of the London financial sector, it remains above that of Spain in the underlying source...
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    News Why I am not always convinced living in EU makes sense

    Would like to point out that this has little to do with the EU as such, but is the UK's overzealous interpretation of EU law. The UK, especially with health and safety regulations, are masters at coming up with bizarre rules and then blaming the bizarreness on EU rules although strangely no...
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    Schools King's College London (KCL) undergrad physics?

    Think the Physics dept at KCL is fairly small, which might explain the variability in rankings. That doesn't mean it's bad, but might mean less choice, if you're looking to to get involved in undergrad research depending on which areas you find interesting.
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    Dutch words for hydrogen and oxygen

    The words Oxygen and Hydrogen have the same meaning - i.e. acid creator and water creator in Latin, respectively. Only difference is that their names were translated into Dutch and German, whereas English retained the Latin name. The discovery that the chemistry actually works differently was...
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    Chi-squared inverse function and incomplete gamma function

    If you just want the quantile (inverse CDF) of the chi squared distribution, that can be approximated with the normal distribution inverse CDF for large numbers of degrees of freedom. That isn't known analytically either, but matlab etc. have good approximations. Or do you want something...
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    GPA: Can you be too perfect?

    That's how college exams work in many countries anyhow. E.g. In the UK an A corresponds to a mark of 70% and someone ever getting close to 100% is exceedingly rare in an individual exam, let alone consistently, would say the average is usually around 60%. Everything's still based on the...
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    Chi or Rayleigh or Ricean?

    And don't think you'll get a nice analytic distribution for this. There seem to be a few numerical methods out there for managing the distribution of a linear combination of non-central chi squared random variables though, which is fairly close to what you want (apart from the square root)
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    Chi or Rayleigh or Ricean?

    Err, sorry, got a bit over-enthusiastic and thought it should fit nicely, but seems it doesn't after all, so yes looks more complicated.
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    Chi or Rayleigh or Ricean?

    It's a non-central chi distribution.
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    Can someone explain this step in the proof of the convolution theorem?

    After the substitution, y is just a dummy variable and consequently independent of x. If it was a definite integral, the substitution would have moved the dependency on x to the integral limits but because the integral is over all space, they are still independent of x after the substitution.
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    Disjoint / Independent?

    Which events are meant to be both independent and disjoint in this case? The only way I can see that two events can ever be both independent and disjoint is if one of them has probability zero. The main events for the coin tosses are - the two events representing the results of each...
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    Disjoint / Independent?

    No, that only works for disjoint events, generally P(A\cup B) = P(A) + P(B) - P(A\cap B) so for disjoint events the third term is zero.
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    Disjoint / Independent?

    Disjoint events are mutually exclusive, which is a strong form of statistical dependence (so if you know event A occurred you know that B definitely did not occur and vice versa), meaning P(A\cap B) = 0 For events to be independent on the other hand, knowing if one event occurred does not...
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    Relation between exponentially distributed random variables and Poisson(1)

    For fixed n, the condition X_k = log ( n ) gives you a probability for each of the exponential random variables to be included in the count. So, what distribution does that mean N has in terms of n, k and that probability? The limit of that distribution as n goes to infinity should then be...
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    How irrational are employers on the topic of related disciplines?

    And yes, for software development roles, people do filter by degree specialisation, but usually the criterion is something like 'a degree in a numerate/technical subject' rather than just CS. So you should be fine with a math degree, if you can show some motivation about why you want to do...
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    What's this weird symbol

    Assuming you mean this one: \neg That's logical not/negation.
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    Programs Which programming languages might a physics major learn and why?

    From a practical perspective, yes C++/python are probably going to be most used. The only reason someone would still want to use fortran nowadays is probably either nostalgia or legacy libraries (the article comparing fortran vs. C above sounded like it was written 10+ years ago, in the meantime...
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    Physics Finish MSc in Physics, work for 3 years in finance, do PhD?

    Would say after 2-3 years you probably still have a decent chance of getting back into academia, if you keep in contact with people and really want to. But the problem is more that there is a good chance you won't want to go back at that stage anymore, 2-3 years is also often the time when...
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    Scaling Pareto between 1 and 0

    In that case the bounded Pareto distribution (also described on the wikipedia page) is probably what you are looking for. That is only defined for ranges that start at values greater than zero though, so you'll have to pick some range and then linearly scale/shift the values to your desired...
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    Scaling Pareto between 1 and 0

    I think you need to specify more exactly what kind of probability distribution you want. The Pareto distribution doesn't start at zero because the PDF has a singularity there, so it can't integrate to 1. Do you want the whole Pareto range rescaled onto the interval from 0 to 1? If you do...
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    ODE with trigonometric functions of solutions

    Are you sure you actually need to solve the ODE analytically? Not sure if that's even possible. Or is the assignment only to qualitatively figure out what the solution looks like assuming you start from the origin? In that case it would be more a case of figuring out which terms dominate...
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    Bell's theorem and foundations of statistics

    The second paragraph of section 3.2 sounds like changing the setting of A affects the value of one of the hidden parameters (which are later measured by B) and vice versa. If that is what you meant, you are breaking the core assumption made in Bell's proof, which is that the settings of the 2...
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    Can grandpa understand the Bell's Theorem?

    The question you asked does not have anything to do with Aspect's experimental setup. In his set-up, there is a switch before the polariser, so the photons would go either through B or C, not through both. You are just unnecessarily complicating the set-up for no purpose. All the extra polariser...
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    Exponential Convolution Erlang

    Your second integral actually evaluates to 0.5 \mu^3 x^2 \exp(-\mu x) All you're really integrating is s. The exponential is untouched because it doesn't contain s anymore after you multiply the 2 exponentials.
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    Can grandpa understand the Bell's Theorem?

    Apart from orienting your polariser up/down or left/right you can also rotate it to any angle in between the two and it will measure polarisation in that direction. So the 3 variables are the polarisation angle of the incoming light and the 2 angles of the polarisers used to measure that light...
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    Solving pde with gaussian function

    You can get rid of the mixed derivative by making the change of variable x = u + v and t = u - v, which is going to leave you with a wave equation plus some extra terms, which would be a more standard form. Now still not sure how to solve it after that, the nonlinear term makes it quite...
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    Why x,y,z?

    X, Y, Z are just one possible coordinate system and it's possible to define others e.g. Polar coordinates, although they will all have 3 components if you ar trying to describe 3d space without redundancy. Using more than 3 coordinates to describe a location in everyday/3D space means redundant...
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