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Jacques

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Everything posted by Jacques

  1. I think zorro is mixing up "Solar wind" with "solar radiation". Solar wind are made of charged particles that are deflected by magnetic field. Solar radiation are electromagnetic wave that are not deflected by magnetic field. Hope it help
  2. That is more than the visible universe, so we basically live in a black hole. Or am I missing something ? Thanks
  3. What would be de radius of the event horizon of a blackhole having the mass of the universe ? Same question whith the barionic mass of the universe ? Just a curiosity...
  4. Hi During the core collapse of a massive star does spacetime stretch ? Is it possible that because of that stretching, some particle get catch in a wave and accelerate to faster than light ? I know relativity prohibit that matter be accelerated faster than light, but when we consider distant galaxies they look like going faster than light because of the space expansion. Is it possible that something similar happen on a smaler scale in supernova explosion ? Thanks
  5. I am not speaking of solar sail although it is very interesting. pmb That what I thaught. It is the ultimate specific impulse. Why is it not used ?
  6. 1- We can measure only the wave length of light 2- You are not scaled: gravity and other force keep you from expanding
  7. If I turn on a laser in space, will it accelerate ? Usually rocket engine send mass to the back to accelerate in the opposite direction. Light has no mass, but has momentum and by conservation of momentum law the laser should accelarate... I am not sure and that is why I am asking.
  8. timo Most of the time, people here reply , but I must admit that often replies goes of topic. Here it is my lack of knowledge about the math in the article that motivated me to post. I thaught that someone who knows the quantum math would give me an appretiation of the validity of what is writen. I find that article and other articles by this author important if it can give a new perspective to quantum physic. I find fascinating the thaught that an electron can be describe as a rotating semi-photon. He use the same math and equation as the standard model, but give some sense to quantum physic. Anyway, if somebody can review and tell me if it is good or not, thanks
  9. Thanks timo for your answers. Do you mean that it is not a reliable source ? Same question about viXra ?
  10. Electromagnetic waves have an electric and a magnetic component, and photon are 'electromegnetic particle' When a photon pass in an electric field, is he modified ? Same question with a magnetic field ? I know about the Zeeman effect and the Stark effect but I am wondering if the direction of the photon can be modified ... Thanks
  11. I found this article and found it very interesting. My humble opinion is that it is better to have an axiomatic approach in science, but I don't know much about quantum theories. Is it true that the Standard Model use a "Babylonian" approach ? Does the maths in the article correct, or is it a word salad ? I would like to have your opinion and comment on that article. thanks
  12. ...the 1919 experiment by Eddington which showed it correctly predicted the deflection of a star's light by the sun The mass of the sun is big enought so we can detect some deflection of star,s light during total eclipse. The deflection is very small but mesurable .
  13. Hi First the mass of the moon is to weak for a gravitationnal lensing that maybe observable. The moon has pratically (almost 0) no atmosphere to produce an atmospheric lensing. If it was the new moon it was probably close to your horizon. Earth atmosphere may plyed a role. But I have a simple explaination. When Venus passed behind the moon it was not long after the sunset, so I guest that the sky was blue and Venus was appearing dimer because the contrast between venus and the sky was lower. Also it entered in lit section of the moon so also no big contrast between venus and the moon. A rought calculation gave me an hour long occultation passing by the center of the moon. During one hour the sky get pretty dark and your eye are adapted to dark and venus contrast against the sky was big also the contrast with the moon also was high because it came back on the dark side of the moon. After sometime your eyes got used to it or may be venus got closer to the horizon and was dimmed by atmospheric absortion. I experienced many time this "WOW look how venus is big" specialy when I spot venus early in the evening and I go check an hour later.
  14. 30 frames a second How can you read any values ? At 30 f/s you should only see a blur on the screen. Does the programm loop back to 100 after conting down to 0 ?
  15. Here. For me the center of the universe is here.
  16. How do you mesure the distance between the two grain ? In the analogy you are like God living outside of the balloon, but if you use the grid you traced on the ballon distance didn't change. It is why I think that the mesurement of distant galaxy won't change over time. We don't have an external ruler to make our mesurement, we only have the redshift. If it was possible to pull a mesurement tape all the way to the distant galaxy, for sure we would get different mesurement with time. But we only have ligth that is expanding (redshift) with space itself.
  17. I cannot tell, I don't understand your question... I am not very good in math like you seem to be, but I was thinking about how to calculate g [math]\frac{G M}{R^2}[/math] but M is not constant if you model the galaxy disk by a disk. M will be proportionnal to [math] r^2[/math] so it will give a constant acceleration
  18. I propose scalar-motion, it can be expressed with a simple number the Hubble constant H0 and has units of inverse time. It doesn't have any special direction unlike vectorial motion. It can also be negative and that is gravity. Also I have taught experiment: Take a perfect mirror box and put some photon of all the same wave lenght. After a billion year the photons would have travelled 1 billion light year in the box. Will it be redshifted ?
  19. That is what I think also I was under the impression that because of gravity space was not expanding.
  20. I agree.Not sure but I suppose that [math] \Lambda CDM [/math] doesn't use that equation ?
  21. I am not completely satisfied by the answers, but I thanks for the effort people did to answer. Noting new all answer by the book, but it forced me to think more deeply about space expansion and photon travelling throught that space. Let follow a photon emitted in a faraway galaxy. In that galaxy space is not expanding, so it is not redshifted before he leave the galaxies cluster and enter the great inter cluster void. There, space is expanding so the photon is also expanding. On it's way space expand and so does the photon until it approach our local cluster. In our local cluster space didn't expand so the space here is contracted compared to the inter cluster space. So why doesn't the photon also recontract ? I read many thing on the subject, and I accepted the cosmoloogical redshift without questioning. Now that I try to go deeper I have many question with no answer. You can give numbers or equations, but what I need is comprehension.
  22. A Novel Test of the Modified Newtonian Dynamics with Gas Rich Galaxies here is a link to the paper. Will read it also
  23. Thanks for your answers. Would it be correct to tell space is created between gravitationnaly unbonded systems ?
  24. Gas Rich Galaxies Confirm Prediction of Modified Gravity Theory Surprising comming from an astronomy professor! What do you think about that. Personnaly I prefer MOND, but I don't know if it explain the lensing by close galaxies of distant galaxies.
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