Recent content by Radiohannah

  1. R

    Hello!May I ask a few questions, I am trying to understand how the

    Sorry, I'm finding it difficult to grasp some of the basics From a Schwarzschild metric You can get the proper and coordinate times, and the time measured by an observer at some distance from the source. I was wondering if you could similarly get a 'distance' from the metric, measured by a...
  2. R

    Hello!May I ask a few questions, I am trying to understand how the

    HOWEVER, may I ask I don't see how you could then interpretate distances from this metric? ie from a Schwarzschild metric? I know that for a stationary observer, the radial and the angular parts would equate to 0. And I know that in general the distance between 2 points separated by dr would...
  3. R

    Hello!May I ask a few questions, I am trying to understand how the

    Hello! May I ask a few questions, I am trying to understand how the metric tensors work in general relativity. In particular, why you would want to make either the radial or transverse part look Euclidean? In what situations is that useful? I am happy that in a very general form, the...
  4. R

    Acoustics - Critical Bandwidths ?

    Solved it! It must be a sum, was mistaking my logs for lns :-(
  5. R

    Acoustics - Critical Bandwidths ?

    Hello! I'm getting a bit confused with how to deal with sound waves that are within one critical bandwidth of each other. I do not fully understand how you are meant to combine the intensities of sound waves when they lie within one critical bandwidth?! I would really appreciate some...
  6. R

    The Shape of the Universe, and General Relativity

    Hello! Cheers! I think I see what you mean. Do the metrics take into account the shape of the Universe? Or only the curvature of space-time by mass (since the shape "has no measurable effect on things like orbits")? I think I am confused because in the metrics I have seen, there is a term for...
  7. R

    The Shape of the Universe, and General Relativity

    Hello! I'm trying to get my head around general relativity at the moment...(!), and there's one aspect of it that's really causing me a lot of kerfuffle. I understand that in an appropriately sized local inertial frame, the laws of special relativity occur. On those scales the curvature...
  8. R

    The Wave Zone Definition

    :-D Cheers! I think we figured it out, we think it just means something really far away....
  9. R

    The Affine Connection components

    Hello! I have a few questions about how the Affine connection works. I know the geodesic equation; \Gamma^{\lambda}_{\mu \nu} = \frac{\partial x^{\lambda}}{\partial \xi^{\alpha}} \frac{\partial^{2} \xi^{\alpha}}{\partial x^{\nu} \partial x^{\mu}} So, for example, if I had the...
  10. R

    Mean Energy Fluctuations

    Great thank you!
  11. R

    Mean Energy Fluctuations

    Hello! I'm getting muddled with the notation in my notes, in which I have \overline{(E-\overline{E})(P-\overline{P})} From which you can get \overline{EP} - \overline{E} \ \overline{P} I can see where these come from, but not where the \overline{E \overline{P}} - \overline{\overline{E}...
  12. R

    The Wave Zone Definition

    The "Wave Zone" Definition Hello! We are trying to figure out exactly what the "Wave Zone" is when considering potentials. We know that a moving charge will generate a "disturbance" in the surrounding fields, which propagates outwards at light speed. This means that for great distances...
  13. R

    Help with differentiating summations

    Mute! I see! Woops! Thank you that makes sense :-)
  14. R

    Help with differentiating summations

    *OH* ok I think I get it, so for my term \frac{\partial}{\partial p_{j}} ln p_{i} all of the terms would be zero apart from the once instance in which the j = i in the summation? And that justifies getting rid of the summation sign? Is that right? Thanks! Hannah
Top