Recent content by theneedtoknow

  1. T

    Will the Einstein Ring Change as the Mass Moves Towards the Observer?

    Awesome, thank you! I needed it more as a hypothetical for a short story I'm writing so it's OK if it doesn't happen on single human lifescales :)
  2. T

    Will the Einstein Ring Change as the Mass Moves Towards the Observer?

    If I was looking at a self-luminous object, and all of a sudden a great pass appeared directly between me and the object, in the line of sight between me and it, I could potentially see an Einstein ring. Q: If that mass then started moving radially towards me (distance to self-luminous source...
  3. T

    Poisson Distribution Help

    I have been analyzing some data at work, and I have measured the occurrence rates of some event. How do I give a one sigma confidence interval to go along with it, assuming it is a Poisson event? For example, I found that something occurs 20 out of 10 000 times, something else occurs 43 out of...
  4. T

    Vectors Perpendicular to Plane: nhat

    Thank you so much for the help!
  5. T

    Vectors Perpendicular to Plane: nhat

    Sorry, not thinking very clearly. I meant to type the set of unit vectors which are PARALLEL to that same plane
  6. T

    Vectors Perpendicular to Plane: nhat

    If I have a vector nhat = [nx, ny, nz] which is normal to some plane, how can I write the vectors (I assume there are infinitely many) which are perpendicular to that plane?
  7. T

    Music Favorite Music Albums - Share Your Top 5!

    I love every album on your list, good taste in music!
  8. T

    Music Favorite Music Albums - Share Your Top 5!

    Hard to pick just 5, given that I am a major music junkie, but they most likely are: Cibo Matto - Stereotype A Cibo Matto - Viva la Woman Depeche Mode - Violator Leftfield - Leftism Moloko - Do you like my tight sweater?
  9. T

    Movies for hardcore sci-fi geeks

    A couple of good, low budget ones are Harrison Bergeron and Thomas in Love
  10. T

    Movies for hardcore sci-fi geeks

    Try Cronocrimenes (Time Crimes), fun sci-fi flick
  11. T

    Gaussian Function in 2-D

    This isn't a homework question at all, but I thought I should try not to pollute the general math forum with it. At work, I am trying to create an artificial distribution of a quantity. It has a peak at a certain location in 2D space (x',y') and then falls off with a gaussian profile in every...
  12. T

    What do (or did) you call your grandmother?

    I called (and still call her) baba
  13. T

    Heliocentric and baryocentric corrections.

    I have a bunch of spectral images of a star taken at various points in the Earth's orbit. I have used IRAF to determine the heliocentric corrections necessary. I am trying to get a rough estimate as to the difference between these heliocentric corrections, and what a barycentric correction would...
  14. T

    Relationship between Lagrangian and Energy

    Thank you! Would you happen to know of any textbooks where this is derived? I have the Landau and Lifgarbagez "Mechanics" one and they do not do so.
  15. T

    Relationship between Lagrangian and Energy

    I know that, for time-independent potentials, we have E=sum (Vi*partial dL/dVi) - L What if one or more of the potentials are time-dependent? Is the relationship between energy and the lagrangian then "total dE/dt = - partial dL/dt "?
Back
Top