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Showing content with the highest reputation on 05/18/18 in all areas

  1. 2 points
    It'll keep you busy for sure. There are 4 considerations for sample size calculations, the first two are difference in means between groups and variances (standard deviations) of groups. Typically the bigger the difference between means and the smaller the variance the less samples you need. There is very little you can do about these - well designed/controlled experiments might reduce the variance a bit. The next two you can choose an acceptable level: they are your probability of seeing a difference in means (just by sheer luck) when really there is no difference and seeing no difference in means when really there is. (These are known as type 1 and 2 statistical errors). They are related so increasing one reduces the other so we seek an acceptable balance - what's worse, saying there is a difference when there isn't or saying there isn't when there is? Typically in biology and medicine we say an acceptable probability of a type 1 error is 0.05 and of a type 2 error 0.2 (usually stated as having a 'power of 80%). This means that if you repeat an experiment which you know has no difference in means 20 times, you can expect 1 experiment to (erroneously) say there is a difference in means. Hope that makes sense: in a rush.
  2. 1 point
    An HGV is a different classification and need not be articulated. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/211948/simplified-guide-to-lorry-types-and-weights.pdf Of course the term is made more difficult by the american pronunciation of the part word 'semi'.
  3. 1 point
    Thanks for your contribution anyway swansont, you’re saying credible things to ponder, and I really think I have to take your viewpoint on the matter seriously, and I will, so thanks for sharing your thoughts on the subject!
  4. 1 point
    I’m already working on it, you’re all actually a great help in the process! I was referring to the surplus of mass that has been measured in the Milky Way, which has to be accounted for (in order to explain the trajectory of all celestial bodies orbiting the BH). We have coined this additional mass the term “dark matter” because it can’t be caused by the mass of the total amount of matter objects in the Milky Way (since all celestial bodies are made up of SM particles). If this can't be explained by normal matter, we're forced to divert to other explanations. It looks like the densest form of SM matter can’t be at the center of a BH (but I haven’t considered Fermi gas yet, as pointed out by @Mordred). However, so far SM particles have been ruled out as an explanation for all the mass we measure. This means that if “something” ("stuff", SM particles) can’t be the cause of mass, it must be “nothing” (whatever that means, I don’t claim to understand the physics of “nothing”), but the point is that there’s no option c, it’s either “stuff” or “not stuff”, so if it can't be A, it has to be B. There’s a difference between “nothing”, meaning a gap/hole in spacetime, and the vacuum in between celestial bodies. The vacuum itself has some kind of neutrality, whereas an actual hole has an attractive force, because of its negative characteristic. Once again, what is mass anyway? The Higgs, the graviton, dark matter, aren’t they all just different forms of attraction? Why would anybody argue that mass must be caused by a SM particle?
  5. 1 point
    I boxed as teen and continue to train people as an adult. I primarily train the basics to friends and co-workers looking to learn for the sake of fun and exercise but did train a guy a couple years ago for a Police/Federal Officer tournament he went on to win. I was good, am still good, never pursued it professionally because it wasn't the sort of life I wanted. Boxing isn't like other pro sports where there is a commission and unions looking out for athletes. In boxing everyone is on their own working with promoters to get fighters made. Too much of a hustle. I saw too talented athletes in the amateurs dedicate years and have hundreds of fights just to end up no where.
  6. 1 point
    All you have to do to stop the property damage is get smart-- The volcano is not unknown or a mystery-- the mystery is why people insist on developing property in the path of the volcano.
  7. 1 point
  8. -1 points
    Magnetic fields are responsible for gravity contrary to Einstein. All charged particles with spin have a magnetic field around them. If you analyze two magnetic fields closely at the same distance apart at all possible orientations to each other you will find a net attraction between the two, this is what is responsible for gravity not mass bending of space. An experiment to confirm this you take a horizontal beam of electrons and accelerate it to relativistic velocities in a straight line and when it leaves the accelerator you measure its deflection angle due to gravity. Since the spin magnetic field around the accelerated electron does not increase, the gravitational attraction due to magnetic field does not increase. With the increased mass of the accelerated electron the downward accelerating speed of the electron due gravity will be proportionally decreased. Under Einsteins relativity the increased mass would produce increased gravitational attraction and therefore there would be greater downward acceleration from gravity than from the magnetic field theory. Further supporting evidence can be found below http://www.enterprisemission.com/antigrav.html