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Strange

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Everything posted by Strange

  1. I think you have avoided answering any questions which would make your intention clearer. I can only analyse my example, because it is the only one on offer. So you have 5 parallel beams going through the lens? Is that right? So, with no diaphragm we get 5 spots from the 5 lasers: With the diaphragm closed down a bit, you get 3 spots: So I guess the question now is: do you understand why this doesn't affect the field of view?
  2. At the the centre of any face of the cube, the centrifugal force would be normal to the surface. As you move away from the centre, the force vector would move away from the "vertical" and it would feel (I think) like you were asking downhill. So the plane surface would feel like a domed surface.
  3. I think it is easier to consider a single light source but whatever. You need to draw a diagram showing where these light sources are and where the rays from them are going. How many light sources do you have in your setup, for example? And are do you mean 3 beams from each light source? Or 1 from each? Or ...? Are they directional (lasers) or just light bulbs? Five what "passing through the lens"? Why do you need a filter? Why do you think that the lamps can't be seen? There isn't enough information in your vague description to say. Draw a diagram and it might be possible to answer and explain why.
  4. Strange

    Trump tweets

    And when you are criticised by the Daily Mail for being too anti-Islam, you know you have a problem.
  5. Because, from every point on the subject, rays can go though every part of the lens to form the image. So if you block some of those rays, you reduce the total number of rays forming the image but you don't change where they come from. To put that in terms of your lasers, if you were to position one at the extreme edge of the field of view and aim it through the edge of the lens then it would be blocked when the diaphragm is shut down. If you leave the diaphragm in that position and, without changing the position of the laser, rotate the laser to go through the centre of the lens then it will again appear in your image. The same thing is true for a laser position in the middle of the field of view. If you aim it at the edge of the lens than it can be blocked by the diaphragm. If you aim it near the middle of the lens, then it won't be blocked by the diaphragm. What that shows is that some rays from every part of the scene are blocked by the diaphragm (so it becomes universally darker as you stop down) but some rays from every part of the image will always reach the film/sensor. This is what my diagram was supposed to illustrate. Apparently you missed the point but I'm afraid I can't think how to make it any simpler. (Which seems to be a recurring theme on your threads.) Again, maybe if you draw the paths of the rays yourself, it might make more sense to you. Or perhaps you can get a 5 year old to explain it to you? Filters? Where did that come from? Are you completely changing the subject again?
  6. Anyone with a basic knowledge of science knows exactly what the outcome will be. See the second post in this thread. Feel free to ask questions about it, if you think it is not sufficiently clear. You can do the experiment for a few dollars, so let us know how you get on.
  7. Black holes are mentioned. But they are not involved in his model of the Big Bang. They get rid of the singularity. There is still the universe expanding from an early hot dense state, aka the Big Bang model. It is expansion that causes the cooling of the universe (as seen in the CMB) not acceleration. I hate to appear picky and banging away at the same point, but the details are important (this is science after all). Expansion happens because of the distribution of mass-energy in the universe. This increases the amount of space between galaxy [clusters] at a constant rate. Dark energy causes the rate of expansion to accelerate. We would have (and did have) expansion even without the effects of dark energy. It is the temperature of the event horizon. Which is the only thing we can know about. In the "regular black hole" described in the link you provided, there is no singularity and therefore no concentration of matter at the centre. I don't know what this says about the theoretical temperature inside the event horizon. It will presumably be lower than the standard model of a block hole, that's all I can say.
  8. Who are you quoting, there? Ah, yes. That makes sense.
  9. A bit of commentary on this: https://gizmodo.com/dark-matter-is-not-dead-1820809277/amp
  10. These are both variations of the "big bounce" model which gets rid of the singularity (but has nothing to do with black holes). I think pretty much everyone would agree with that. The expansion happens without dark energy. Dark energy is suggested to explain the observed and unexpected acceleration of expansion.
  11. Strange

    Trump tweets

    And now ... http://www.bbc.co.uk/news/world-us-canada-42166663
  12. Strange

    Trump tweets

    He has come up with a classic. I thought this was a spoof when I saw it... "your favorite President (me)"
  13. Nicely put SJ. (Edit: I made a little joke, but reading the OP again, I don't think it is appropriate)
  14. I'm guessing that was supposed to be "we don't stop looking when we think we've found answers" (as would be obvious from the rest of the post).
  15. Actual Experiment suggestion: why not just take a picture of that with different apertures?
  16. You don't want to discuss what the outcome of your actual experiment is expected to be? Or why you expect the results of your actual experiment to be different from that predicted by optics? And why isn't taking pictures a good enough experiment? If you want to see if there is any difference between a general scene and light from point sources/lasers then why not take pictures of those two things?
  17. Why wouldn't it be? That is why less light gets through. In what way do you think they are different? Perhaps if we could understand where your confusion lies, it might be possible to explain where you are going wrong. (Although, based on past experience, there probably isn't much hope of that.)
  18. You could buy a cheap laser pointer ($1), a cheap magnifying glass ($3) and a piece of cardboard ($0) to make different size apertures in. What do you hope to find?
  19. You may or you may not. Depending where they go. It isn't. And I thought it was your entire point. Why would they? Why not just take some photographs? Or draw a diagram? Or learn some basic optics?
  20. That depends on the position at which they go through the lens. Those near the edge of the lens will obviously be blocked by a smaller aperture. This, equally, obviously, has no effect on the field of view.
  21. The Big Bang was not really an explosion. This is another key difference from your idea. Even if a black hole could explode and send huge amounts of mass and energy into space, that is not what the Big Bang model describes. The Big Bang model does not say: there was empty space and then something exploded to fill it with matter (and energy). The Big Bang model does say: the universe has always been completely full of matter and energy. The universe has expanded and cooled over time. As a result, we get the CMB and the formation of structures like stars and galaxies. It will contribute. But that momentum can only have come from the mass and energy that was already present. So it isn't increasing the mass. We don't really know anything about the universe that early on. But if we assume the same rules apply, then momentum, energy and mass all contribute to gravitational effects and can all be considered equivalent to mass. It is equivalent to mass (e=mc2). So, for example, (as noted in another thread) hot water has more mass than cold water because it has more energy. If you were to trap photons (no mass) in a box, the box would have more mass because of the energy of the photons. We don't know if it had infinite energy. If the universe is infinite, then (presumably) it did. If the universe is finite, then it didn't. http://www.skyandtelescope.com/astronomy-news/ligo-sees-smallest-black-hole-binary-yet-1611201723/ I don't have much to say. Not everything is a quantum fluctuation. And I don't know how quantum fluctuations would be affected inside a black hole. My guess is, not much. Other than by gravitational time dilation - but as that depends on the observer and we cannot observe it, it seems a bit irrelevant.
  22. Who is this "molecular biologist"? Of course they can give it to a non-physicist. Although if that person has done enough physics to deserve a Nobel Prize, I'm not sure how they can not be a physicist.
  23. I added that as my personal opinion. Not as a rational argument. I should have added: "This is purely an irrational belief with no logical or evidential basis." Sorry about that. Exactly. That is why I don't usually mention my personal belief about this. It is irrelevant and irrational. (But probably quite a common one.) Then explain exactly how you would test this, using the scientific method. Nope. Can you provide a little more detail? What would you measure? What would you compare it with to test if it is real or sim? The difference is that in that case, we can compare the two items and we can compare them both with a sample of the real thing (and / or a sample knock-off). A more accurate analogy would be that I give you one sample of an object (for example, a coin from a country you have never been to) and ask you if it is genuine, a forgery or just a toy. How do you tell which it is? Scientifically.
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