michel123456

Senior Members
  • Content Count

    5787
  • Joined

  • Last visited

Everything posted by michel123456

  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. 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?
  5. 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?
  6. 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?
  7. 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.
  8. 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?
  9. 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?
  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. Hexagonal pattern works well for surfaces (2D). However in 3D I wonder what kind of "hexagonal pattern" it really is. The "chicken wire" pattern shown in Wiki is a mix of hexagons & pentagons.
  14. 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.
  15. 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.
  16. 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?
  17. michel123456

    Intriguing Finds at KPg boundary in North Dakota

    From page 36 of the appendix I am not sure that the flow direction is axial. If i remember correctly deposits of branches from a regular wave at the beach is mostly parallel to the shore, not axial. IOW maybe the flow is perpendicular and not axial. Simple guess.
  18. michel123456

    A disappointing tale.

    I agree about the prematurate closing. I was also impressed by the " Unfortunately, after the publication I will lose intellectual property rights on my technology, Such is the legislation " On the balance we have on one side personal fame (& money) and on the other side we have universal benefice. And as it seems personal interest is heavier. Of course.
  19. michel123456

    Time Travel help

    Exactly. And getting back in time you would be younger. In no case you would be a double of yourself, observing yourself. You would be the one & same individual, younger, with no clue of what happened. The problem in the scenario is what happen to the future? Will you disappear from the future? That does not sound reasonable. The time travel concept has that kind of issues.
  20. I stumbled upon this ancient time-keeping device,The Chandelier Clock of Ibn Yūnis , The principle is simple, each lamp is burning a certain amount of time. You have to put in each lamp a specific quantity of oil in order to burn, the first for 2 hours, the second for 4 hours etc. With the subtility that in antiquity (& medieval times) the hour was not standard but it was a portion of daytime. When the day was short, the hours in sunlight were short & in night time were long. Here below the description of the object And here a couple of images I am seeing that the lamps are not at the same height. i see they are all connected (for same air pressure? I don't understand the central container and the tubes that join the one with the other. Has anyone an idea? Thanks
  21. michel123456

    Direction of time

    The width is the number of soldiers, each mm for 10,000 The large light brown is the invading army crossing the Niemen river (422.000 troops). The black is the return trip from Moscow(only 10,000). The full legend can be found on the link to the map. English: The map's French caption reads: Figurative Map of the successive losses in men of the French Army in the Russian campaign 1812–1813. Drawn up by M. Minard, Inspector General of Bridges and Roads in retirement. Paris, 20 November 1869. The numbers of men present are represented by the widths of the colored zones at a rate of one millimeter for every ten-thousand men; they are further written across the zones. The red [now brown] designates the men who enter into Russia, the black those who leave it. —— The information which has served to draw up the map has been extracted from the works of M. M. Thiers, of Segur, of Fezensac, of Chambray, and the unpublished diary of Jacob, pharmacist of the army since October 28th. In order to better judge with the eye the diminution of the army, I have assumed that the troops of prince Jerome and of Marshal Davoush who had been detached at Minsk and Moghilev and have rejoined around Orcha and Vitebsk, had always marched with the army. The scale is shown on the center-right, in "lieues communes de France" (common French league) which is 4444 m (2.75 miles). The lower portion of the graph is to be read from right to left. It shows the temperature on the army's return from Russia, in degrees below freezing on the Réaumur scale. (Multiply Réaumur temperatures by 1¼ to get Celsius, e.g. −30 °R = −37.5 °C) At Smolensk, the temperature was −21° Réaumur on 14 November.
  22. michel123456

    Direction of time

    I am not sure what you are speaking about. Do you know the Minard map? Interestingly time flows in both directions. https://en.wikipedia.org/wiki/File:Minard.png It describes the campaign of Napoleon in Russia & its losses. In this map, time & displacement are essentially the same.
  23. michel123456

    Direction of time

    ? Please expand.
  24. michel123456

    Direction of time

    Interesting question. Under normal circumstances you will get answers that say time has no direction (unlike space where you have directions). However: When you look at the night sky & far away at a star, you see the star as it was a long time ago. The entire night sky is an image of objects as they once were. In other words you are looking at the past of the Universe. The farther away, the more in the past. The closest in space the closest in time. Thus one should conclude that since Time goes from the past to the present & to the future, Time goes from the outside to the inside. That counts for each observer: each observer see time going from out to in, where out is the past. The present touches exactly your skin and your eyes. The future is inside you (but that gets somehow philosophical).
  25. At the risk of being completely idiot here below something I wonder: Step1: the positive & negative on the number line. This above is a representation of the number line, the Real numbers going from zero to positives on the right & negative to the left. Step 2: When it comes to multiplication, we can show the sign rule in the following diagram. Where we have the product of 2 positives is positive. The product of a positive with a negative is a negative, the product of 2 negatives is a positive. Step 3: From the diagram above it comes out that the square of a Real number, positive or negative, is always positive. As shown below, the 2 squares are in a positive area. Step 4: Then we go to imaginary numbers (Complex numbers), in such a way that negative squares can be handled, as shown below. Where we see that i^2=-1 (the blue square). Question 1 is: where is the catch? Why is this diagram wrong? Why -i^2 (the red square) shows negative in the diagram? Although the correct answer is that -i^2=1 Question 2 is the following: what is the sign of 2i? Is it positive or negative? Do we follow the rule of the Real numbers, or the rule of Imaginary numbers? Question 3 is: how can you combine the Real number diagram with the Imaginary number diagram? Where is the common axis? The only common feature is a point: zero.