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About michel123456

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  • Birthday 06/08/1960

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    Athens Greece
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    time & space
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  1. michel123456

    Fire in Notre Dame in Paris

    FYI some idea of what was there before destruction by fire. It is in French but the pictures are speaking for itself. http://hermetism.free.fr/Viollet-le-duc_architecte.htm The peak of the roof (the "arrow" or "fleche") was not soo old, it had been rebuild by the renowned architect Eugene Viollet-le-Duc in 1859, with conductor of works Georges. I am afraid there are no many "Georges" available today to redo the work. It was a wooden structure coverted with lead. Not a stone in it. It covered the stone structure that was below the base of the roof. to be noted that the wooden roof did not even touch the stone vaults. The roof stands directly on the pillars. See section here. If the Fleche had not collapsed, the stone vaults would have stopped the fire (as they did for most of the building) because there is no connection between the building rooms & the void of the roof: you have to go up to a terrace outside & enter the roof through a small door.
  2. michel123456

    Stunning picture of the Large Magellanic Cloud

    Right, but I read that the Large Magellanic Cloud is ≈163,000 light-years away. That leaves plenty of time.
  3. michel123456

    Stunning picture of the Large Magellanic Cloud

    What is your problem with that? what do you mean with "do not exist that long"?
  4. Nice. In this case doesnt'it mean that the accretion disk is a spiral? And that the observer close to the EH , looking outside, will observe the Universe as if it was spiraling around him, in a similar way as we are actually looking at the Milky Way?
  5. All this description makes a BH look like a deep well. It does not look like a solid material, like stone or steel (which are examples more massive than water). How comes?
  6. Happy to read that from someone like you. If that is true, then for the external observer the BH is void, all its mass lies on its surface at the EH.
  7. I keep not getting it. Take the example of horizon that divides sky with earth. Isnt'it observer dependent? Isnt'it at a different spacetime coordinate for any observer? Can you look at the same horizon than anyone else? Doesn't its spacetime coordinates depend on your state of motion?
  8. No not this again: The Speed of light is invariant AND relative. Take the analogy of the horizon on Earth: the distance to the horizon is the same for everybody (for a specific height) aka it is constant. And it is relative to the observer. The same goes for SOL but at another level, it is not distance that is constant & relative, it is velocity. That is my question: why are you so sure of this? If the Theory you are using to calculate the EH is Relativity, then how can you be sure that the result of your calculation is absolute?
  9. In layman terms a horizon has a double characteristic: 1. it is a kind of limit to the observation, a surrounding circular line that defines the limit between the sky & the earth: what is observable & what is not 2. It is a boundary that is tied to the observer: you can walk toward a point of the horizon on Earth but you will never be able to reach it because the horizon is your particular horizon and it is moving with you. IOW the horizon is relative to the observer. Does an Event Horizon of a Black Hole follow the 2nd characteristic? And if not, why? I mean, if you try to approach the EH, will it go further the same amount as you have progressed? (because of the deformation of Spacetime) Or can you eventually reach an EH (although you cannot reach the horizon on Earth). Note: the question arises from the fact that the theory surrounding BH comes from the Theory of Relativity, which is relative. Or to state the question otherwise: what part of the Black Hole observation is relative to the observer and what part of it is absolute?
  10. But from this diagram below I understand that the rays of light enter inside the BH. And in the BH, space is intensely curved, but for any observer living in it I suppose Space is straight, light rays are not curved, and time is different. I suppose that for an internal observer things are just as usual. Why would it be different? With light going at C as for us.
  11. If the particles have lost the property of mass, where does gravity come from? Doesn't that mean that gravity is something transcendental? And second question: if space is so much curved in the BH that straight lines become curved, how can we deduce volume & density? Isn't it an error to measure it from our FoR as it is was a ball in regular space? And 3rd question: from the diagrams as explained in the video I understand that an observer that is inside the BH must have be able to observe events happening outside the BH (since the rays of light are entering the BH) In this case, how can he figure out (measuring) that he is inside a BH or not?
  12. michel123456

    First real Black Hole image - 10 April 2019

    Stupid question: does that mean that in a BH the atomic nucleus is compressed?
  13. michel123456

    Intriguing Finds at KPg boundary in North Dakota

    I believe one interesting factor is the following: do the branch have the same orientations with the fish? If yes, then it would show that the fish were dead before being deposited by the sea. If not (a random or other disposition) it would show that the fish were alive, for example as the result of being hunted, disoriented or sick. Or eventually the extraordinary event of the Chicxulub impact would have produced an extraordinary deposit, and that makes sense too.
  14. michel123456

    Intriguing Finds at KPg boundary in North Dakota

    Cherry picking this picture in order to explain: Of course there are other pictures showing more random distributions, but I couldn't spot any where the fish is oriented perpendicular to the shore.
  15. michel123456

    Intriguing Finds at KPg boundary in North Dakota

    I mean, a branch on a wave does not take the position of the surfer. A surfer will go on its axis & ride the wave. But if you take a simple plank, or a branch, it will float in a parallel way to the wave and be let on the shore this way. Have you made a small experience of how a tsunami would have let the dead fish on the shore? Would the fish be oriented (as you say) axially in the direction of the wave, or perpendicular to the direction?