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pzkpfw last won the day on June 14

pzkpfw had the most liked content!

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About pzkpfw

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    New Zealand
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    B.Sc. Computing
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    Born, grew, living, working.
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    Self employed programmer.

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  1. why lepton?

    Like most forums, you get an automatically assigned group or type name. The exact names depend on the forum, these are sciency ones. It'll change as you make more posts; look at different people, their post count and their title. Never to be taken seriously. (Unless it says "moderator" or "administrator").
  2. 3 Choices, pick one:

    I was thinking not just how we'd screw it all up again afterwards, but how these hypothetical aliens dealt with the issues of now. As in, would they kill 50% of us, and force the survivors to live a pre-industrial agrarian life. Would we choose option 1 then?
  3. 3 Choices, pick one:

    Exactly how would 1 be accomplished? That would affect whether it's a good choice.
  4. Original Solution to the “Liars Paradox”

    I think the OP misses the point. In day to day English I might say "I am seven feet tall, well, actually, I am lying". Clearly the bit I'm saying is a lie, is the "7 feet tall", bit, and saying that I'm lying is not itself intended to be a lie. But as a logic exercise, thinking about what "I am lying" - by itself, and referring to itself - really means, is a very different thing.
  5. What color is the sky on Mars?

    Wikipedia has a bunch of stuff: https://en.wikipedia.org/wiki/Mars#Climate
  6. Is the past infinite?

    You should watch "The last tango in Paris" (And do that course in logic.)
  7. Aperture and Field of View

    It's not about "defending", it's about "discussion". Nobody wants your apologies, we want to understand why you think what you do, and help you. You wrote: 4) extra light off. Lasers on. Only three beams go through diaphragms 5) five bright spots visible from screen Nobody here understands how you get step 5 after 4. It's very simple, all you need to do is draw a diagram showing how you can see all five spots in step 5. What path is the light following? (Move the discussion along, instead of getting upset and defensive.) Your earlier diagram is a good start.
  8. Aperture and Field of View

    There is no discussion if you can't explain (or diagram, or whatever) why you think your result would occur. Why would you see all five spots? (If you think that your step 5 would show 5 spots, given your step 4; it should be possible for you to draw a diagram showing the path you think the light is taking. Does the light do a loop-de-loop? A figure 8? How do you see all five spots when, given your step 4, two of the beams were blocked?)
  9. Aperture and Field of View

    Step 5 (of your latest set) is still wrong.
  10. Aperture and Field of View

    Step 5 - wrong. How do you get the five bright spots if 2 of the beams are blocked?
  11. Aperture and Field of View

    OK, so step 3, note that with the lasers themselves turned off, and the scene lit by some other source, the "lasers" may as well just be "toasters", because you're not talking about the beams emitted, you're talking about the devices themselves. So, as per post #2, the aperture won't stop you seeing any of the devices, but it will affect how much light from them gets to the screen. Note four paths from the toasters to the lens shown here, but 2 paths to the screen. The aperture has affected how much light gets through, but not the field of view. (A but hurriedly drawn, sorry. Gotta go out soon.) Step 4 then gets a bit complicated. If you turn the lasers on, but keep the "other" light on also, you'd still see the five laser devices, but now you'd also see three red spots of the laser light; two of the beams are being blocked by the diaphragm (depending on the opening size). The lasers (when turned on) are just demonstrating how some paths of the light get blocked, but some don't.
  12. Aperture and Field of View

    Weird. Why then do you say turn off the lasers in step 4? If they are already off? In any case, at step 3, if the overall scene is lit by some other source, then the physical laser devices will be visible. Just like the head and feet of the stick figure in post #2. (Because you're not talking about unidirectional beams of laser light, you're just talking about a normally lit scene that happens to contain 5 devices, that happen to be laser light emitters). But then, in step 4 (off lasers, still off), what beams are you talking about?
  13. Aperture and Field of View

    Your argument never made sense. It amounted to "A, then magic, then C". Please look at the diagram, and tell me why what I drew for the blue lines would be wrong. Assuming you mean "on" in step 2). 3) No! The aperture size will affect which beams go through! (Note, we're talking lasers here, not simply an image as in the diagram shown in post #2). 3) edit: also now "lamps"? Eh? Lasers or lamps? Which is it? See comment at bottom ... 4) What? With the lasers off, what beams are there? I think maybe in all of these posts, you've got some extra information about the scenario that you are assuming but not actually mentioning.
  14. Aperture and Field of View

    I had a moment, Dalo, so took your diagram to the next logical step - diaphragm closed a bit. Please explain what your filter does to make how I've shown the blue rays wrong. Even better, draw it yourself. (This is basically the same thing Strange asks above.)
  15. Aperture and Field of View

    I greatly appreciate the effort, but that does not at all explain why you think the filter will have any effect. Your diagram shows the diaphragm open to a point where all 5 rays go through. The filter won't change that. The key is - when the diaphragm is closed a bit so only 3 rays go through - what effect is the filter having? ... that's the bit you need to diagram.