# Jacques

Senior Members

562

1. ## Oldest galaxies found

They found very evolved galaxies cluster 9 billion light year ago! Does it chalenge the BB model ? http://www.newscientist.com/article.ns?id=dn7087 Choice quotes: Also see: http://www.physicsweb.org/articles/news/9/3/2/1
2. ## Gravity model

The way I understand it I think so, but I cannot realy tell because it is not a model I invented. The difference with Einstein space curvature is, it is not a static curvature the space is constanly created by the expansion and the mass is constanly absorbing it. My purpose to post that here is to see if that model make sense.
3. ## Gravity model

The same way as with Newton equations except that at a great distance the expansion of space will get a bigger and bigger influence. The model doesn't change the equations of gravity it is just a conceptual difference. Newton didn't had any explaination of how gravity was working, Einstein explain it by the curvature of space-time.
4. ## Gravity model

I thougth that there would be more reaction on that model. No more action at distance. No propagation delay... I don't know if there are some professional astronomer here but I have a question for them: When a new asteroid is discovered or to compute the trajectory of a new space probe do you use Newton equation or Einstein equation ?
5. ## Gravity model

The idea here is that things that have mass doesn't expand because mass is the opposite of expansion.
6. ## Gravity model

I know it is not a very scientific term What I mean by eat up is space is absorbed or detroyed. It is the inverse of the expansion where space is created. In more scientific term we need to define scalar motion: Scalar motion is motion without direction like the expansion of space. The expansion of space occure in all directions at te same time. Scalar motion need only one value to be defined: magnitude. A positive magnitude means an expansion, every locations are going away from each other. A negative magnitude mean every locations are going toward each other. The expansion have a positive magnitude and the gravity a negative magnitude. Thay both are scalar motion.
7. ## Gravity model

2- The action is instantaneous because there is nothing propagating. No it is not a new idea, but it is a new way to illustrate a concept from Larson http://www.rsystem.org/nbm/nbm05.htm You can also make a parallel with the spacetime curvature of general relativity except that is a dynamic process.
8. ## Gravity model

The universe is expanding in all directions. It is not the galaxies that moves away from each other, but space itself who is expanding. Space is created between the galaxies. What was a million light years long is a million and one light year long. (You can use Hubble constant to know how long it takes) Here on earth we don't feel this expansion and we have no clue that this expansion is happening in our galaxy. Why ? Is it possible that is because the earth and all other masses in the milkyway "eat up" that space created by the expansion ? Let suppose that's the case: The universe is expanding and all masses eat up that space. The bigger the mass the more it can eat up space. Also the mass eat up the space all around it so the effect is proportional to the inverse of the square of the distance. Now let see what happen if we have two mass: each eat up the space all around it slowing down expansion betwen them and if the masses are big enougth or close enought the distance betwen them will decrease. Some observations: 1- There is no need for a medium or some kind of particule 2- The action is instantaneous 3- The action cannot be shealded What are your thougth about that ? Thanks
9. ## Changing The Speed Of Time

When I was young I decided to increas my memory. Before falling aslepp, I was reviewing all my day, triing to remember everything I did, the name of that girl and the other, how I was feeling, all what i learned at school,etc... It was kind of going back in time. I also had these experiences of time slow down, I had time to think that it would be beter to have a scar on my hand instsead of my head, i knew it would heart. I think adrenalin is for something in this feeling. In an accident the adrenalin rush in your body. Some psycotrope can alter our perception of time

Thanks
11. ## Alpha radioactivity decay question

Hi In the decay of U238 -> Th234 + He4 why He come out ionized ? The nucleus of U is surrounded by 92 electrons and when the alpha particule is emitted by the nucleus it must goes through this cloud of electrons. Why doesn't the alpha particule doesn't capture the two electron it is missing to get electricaly neutral ? What happen to the 2 excess electrons left on the Th atom ?
12. ## Horizon's Noisy Fusion

Here are some articles http://www.physics.ucla.edu/Sonoluminescence/sono.pdf http://www.physics.ucla.edu/Sonoluminescence/sono2.pdf
13. ## The Speed Of Dark?

Is it a question that make sense to you ? Not for me
14. ## The Speed Of Dark?

Again a definition in term of what it is not... I would like a definition without the words "not" or "absence" Dark is ???
15. ## The Speed Of Dark?

Can someone give a definition of dark or darkness in term of what it is and not in term of what it is not ?
16. ## The Speed Of Dark?

Light can be a property of something like the light car, but light is also something. When we speak of the speed of light, we don't speak of the speed of the property but the speed of the thing we call light. If you realy want an answer you must provide a definition of the "thing" you are calling "dark"
17. ## The Speed Of Dark?

What I mean is: dark is a property. It is not something. How can you discuss of the speed of a property ? You can discuss of the speed of the dark car. But you cannot discuss of the speed of dark.
18. ## The Speed Of Dark?

Dark is a quality. How is it possible to ask a question like that :"what is the speed of dark?" The speed of dark matter ? The speed of dark energy ? The speed of the dark car ? Again dark is a quality not something.
19. ## how many rotations on it's axis

http://www.mmscrusaders.com/newscirocks/astro/sideral-solar.htm Solar years 365.2425 Sideral years 365.2465
20. ## Can Black Holes Exist?

Welcome Rootje I am also new here but I posted the same question http://www.scienceforums.net/forums/showthread.php?t=8289 I think that most people are certain that blackhole exist. JHAQ We are all outside observer. Universe been a finite time, so no singularity had time to form. mass is not infinite, the density is (in blackhole theory). So we have the effect of the mass of the black hole. Some are suppose to be suppermasive at the center of galaxies. Many many million solar mass! Near the center of a galaxie very violent phenomena are detected in X ray images. Motion of the star need big mass there.
21. ## Black hole formation

The theory tell us that (http://hyperphysics.phy-astr.gsu.edu/hbase/astro/blkhol.html#c1) So a neutron star of 3 solar mass always colapse to a black hole. The neutron star radius is decrease with time. When it start being a neutron start it was many kilometers of radius and is going to zero radius. Now what will see Jo from is base situated at a safe distance from the neutron star who start to collapse. How fast would it go ? Joe see the radius shrinking realy fast. From 30km in radius to 20km it took less than one second (on Joe's time). The gravity of that mass will produce some time dilatation. You will find the gravitational time dilatation equation: http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/gratim.html#c4 I try to reproduce it here: T=T0 / (1-(2GM/Rc^2)^.5) You can see that when the radius get smaller the time dilatation increase. I can also see that when 2GM/Rc^2 approach 1, the time dilatation tend to infinity (time stop). Let find the radius where the time stop: 2GM/Rc^2=1 2GM/c^2=R G=6.67*10^-11 m3 kg-1 s-2 M=3 Solar mass= 6*10^30 kg c=3*10^8 m R=2*6.67*10^-11*6*10^30/ 3*10^8*3*10^8 R=8.899 km So Joe's see's the neutron star shrinking slower and slower. If he stay there an infinit time he will see the radius at 8.899 km. Also 8.899 km is the Schwarzchild radius, where a neutron star start to bee a blackhole. Conclusion a blackhole would take a infinite time to form. The "singularity" will never have time to form. Is there something I am missing ???
22. ## Big Bang and black hole

Can you explain more why you thinks that's wrong?
23. ## The importance of multiple time dimensions

You just need to register Take time to read before to make your opinion.
24. ## The importance of multiple time dimensions

See http://www.rstheory.com/ go in the book section: Nothing but motion. It is a theory where the fundamental entities are motion. Motion is space/time and motion is 3D. The space aspect of motion is 3D and also the time aspect is 3D. I find this theory very interesting and it take an open mind to accept some of these concepts. If some people are willing to take a look I would like to have there opinion. Thanks
25. ## Why C?

I have no idea why it is that speed. I think the big question is why it is always that speed no matter the speed of the source or the observer. Einstein explain that in his theory of relativity by making time varied. It is a concept that we are not willing to accept. Our view of time is something absolute. Time flow always the same way... But, as strange as it seem we can't just ignore the data from the GPS nad other experiments.
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