Jump to content

timo

Senior Members
  • Content Count

    3438
  • Joined

  • Last visited

  • Days Won

    1

timo last won the day on January 9 2020

timo had the most liked content!

Community Reputation

578 Glorious Leader

About timo

  • Rank
    Scientist

Profile Information

  • Location
    Germany
  • Interests
    Math, Renewable Energies, Complex Systems
  • College Major/Degree
    Physics
  • Favorite Area of Science
    Data Analysis
  • Biography
    school, civil service, university, public service, university, university, research institute (and sometimes "university", as of lately)
  • Occupation
    Ensuring a steady flow of taxpayer money to burn

Recent Profile Visitors

23963 profile views
  1. What you talk about seems more like a method for calculation to me than an actual measurement. You can indeed calculate the volume of a body by taking a surrounding volume and then subtracting the parts of the surrounding volume that does not belong to the body (in your language: the volume filled with gap values). This may in some cases be an efficient method, e.g. for a block of stone with a cylindrical hole. In the general case, if you have a generic way to calculate the amount of gaps then you could probably use that method to calculate the volume of the body in the first place. This, as y
  2. I never heard that mentioned as an issue for actual projects. But yes, maybe. How, specifically, do you think that lack of water is a problem for solar power projects?
  3. Or you take the engineering approach and just read-off provided numbers: https://globalsolaratlas.info/map. If I remember correctly, the tool even has a "mark an area and integrate" functionality. I'd like to say something constructive here. But I find it hard to make out what this thread is about, or to add anything meaningful on this very vague level. I mean: Yes, solar panels generate electricity. Yes, you can put them on rooftops. And yes, there is lots of sun in the equatorial regions. And to Swansont's post: Yes, there are problems in detail. Transport and storage are somewha
  4. When it comes to experiments on black holes, it gets a bit tricky. You cannot produce them in the lab, and none of these things exists naturally on earth. In fact, we had put lots of efforts into even detecting anything in the universe that we concluded/agreed must be a black hole. While double-checking if even that has happened, yet, I ran into an article claiming that 2019 was the first time you could get an image of a black hole (https://www.sciencemag.org/news/2019/04/black-hole). Don't pin me on the accuracy of that statement, but my point is: It is already pretty challenging to detect bl
  5. There are lots of answers to that question. For some, the answer is that there is a pedophile ring drinking children blood in the backroom of a pizzeria (*). If you haven't found your answer in this thread you should invest the time to be a bit more specific about the question. (*) Rumor has it that this actually is some people's answer about the question what climate science is about, too.
  6. I understand that you are saying that light travels faster than sound or nerve signals in the body. From that you jump to "I think that the point when the action is created is ‘ground zero’ and might be faster than light as it takes up no time. It’s hard to explain but I think you get the idea". Well, ... I do not get the idea. I even had to look up the term "ground zero". But it did not help to know that it means a point on the surface that a bomb explodes over. I do not understand what you are trying to say, so it is hard to give constructive advise here. I think it could make se
  7. The quoted part of the text you provided seems correct to me. In particle physics, there is a concept of a parton. A parton is the thing that does the core interaction when a proton is shot at something else in a particle collider ("core interaction" is the part of the process with the highest energy, the one that you draw Feynman diagrams for to describe it). Experimental physicists have a very pragmatic approach to these partons: They define a probability to get a certain parton (a quark or a gluon) with a given momentum from the proton. These probabilities can be taken into account when si
  8. The explanation of the photoelectric effect and the theory of relativity would match that criterion. I kind of thought that Isaac Newton had a job as master of coin or something like that, but I could not verify that. I am not aware of any more recent examples - not even the proverbial exceptions that prove the rule. That makes me wonder to what extent "only scientists make contributions to science" is a tautology (i.e.: science is defined as "what professional scientists do"). For example, you could argue that Mark Zuckerberg has started the largest sociological experiment in the history of m
  9. Not sure I understand what you are asking for - I certainly don't know what you mean by empirical cycle or retrospective study. But to me, the general approach seems to be: 1) Define one or more quantitative measures for the sale of phishing tools, e.g. number of sales, volume of sales, number of different products offered, number of different products sold. 2) Find data source from which you can determine these measures. Note: The actual progress may be doing this step first and then defining measures that you have data for - it was just easier for me to describe the steps in this o
  10. I don't think I understand anything you just wrote. But I'll give it a try: - "Does -f"(x) imply -1 ?": -f''(x) means -1*f''(x), if that was your question. It does not mean that f(x) = -1 or f''(x)=-1, if that was the question. - "Does linear differential reffer to a "radius"?": Differential equations are a special type of equations that relate functions and their derivatives. They one of the most important mathematical concepts in physics. 'Linear" is just a mathematical property of this equation. - "When you say normalization is ignored, is that for ""All QM waves?"" ": Usuall
  11. Wave functions are solutions of linear differential equations. Mathematically, solutions to linear differential equations contain sine and cosine (or, equivalently, exponential functions with imaginary exponents). The Pi comes in from them. Example: Imagine the Schroedinger equation for a free particle would be f(x) = -f''(x), where f''(x) is the 2nd derivative of f(x) with respect to x. A possible solution for this is f(x) = sin(x) (normalization ignored for this example). The wavelength of this wave is 2*Pi.
  12. I find it really hard to get a coherent picture of the opening post. I see three different aspects that trigger different tones of response, some of which are pretty redundant with the replies given already. So maybe I'll just briefly touch all three aspects to show why at least I have problems with getting a clear picture of this thread. First, there is the relatively long explanation about sums or averages not giving the full information about the individual components that contribute to them. That is correct, mathematically trivial and well known to everyone working in any field
  13. C++ supports state-of-the-art random number generation. So it would be easiest to use a c++ compiler for the code (I expect that it should compile the C parts just fine) and pick an rng that is provided by the language standard library. So: Pick up to one: http://www.cplusplus.com/reference/random/ . I do not expect that the choice of the rng matters for this case. But it is a good habit to never run a Monte-Carlo simulation without a good rng, and including one is really easy in most programming languages.
  14. Do I understand it correctly that the issue you see is the following: One unit in x-direction is a different amount of pixels (or cm on paper, if you'd print it out) than one unit in y-direction. Is that what you mean? That is indeed the case. I have never considered a problem. In my experience, this is the default behavior of most plotting engines. It is normal that in addition to looking at the shape of curves you also have to look at the numbers on the axes (small effects can often look large if you just zoom-in into the graph). And I do think there are more use-cases for having different s
  15. I kind of did what in hindsight I feel should have been provided by you in your starting post: Created the plots you spoke about and posted them here. The code is f = function(x) x*x*x d3 = seq(-3, 3, 0.1) d5 = seq(-5, 5, 0.1) dx = seq(-3, 5, 0.1) plot(d3, f(d3)) grid() plot(d5, f(d5)) grid() plot(dx, f(dx)) grid() The created plots are attached. I see no problem with them. I am not aware of any technical problems that R has. While not the question: I do not recommend to get used to R just because it has the reputation of being the most common software used in statisti
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.