# Jacques

Senior Members

562

1. ## Gravity and relativist mass

OK F=ma Like you said on earth a=9.8 m/s^2 m is the rest inertial. not get on a train going at a speed .9c Now relativity tell us that the mass increase by a factor dependent on the speed (some gamma factor). You are alot better than me in math so I let you do the computation Now we have for the mass: m(inertial) + m(relativist) Now to compute the force of earth do we use the 2 component of the mass (inertial + relativist) or just the inertial mass ? F = ( m(inertial) + m(relativist)) * a(earth) or F = m(inertial) * a(earth) ???
2. ## Gravity and relativist mass

Weight is the mesure of earth force of gravity on a mass.
3. ## Gravity and relativist mass

My feeling is yes, but I know there are some debate on that.
4. ## Gravity and relativist mass

You mean that if I have a 1kg mass and weight it at rest I will measure 9.8 Newton force and if I measure the same mass in a moving train I will measure 9.8 Newton plus a little bit (depending of the speed of the train) ?
5. ## Gravity and relativist mass

A simple question: Is relativist mass subject to gravity ?
6. ## Relativist mass increase

Usually the gamma factor is applied to the mass but you can apply the inverse of gamma to the force and you will get the same equality. Some observation: the photon who mediate the electric force is redshifted from the point of view of the particule. Redshifted means less energy. That's maybe a way to explain the ineffeciency of the force.
7. ## Relativist mass increase

Electric force is mediated by photons who are frame independent. My original question was is there other proof for the increase of mass at velocity near the speed of light ? The mass increase is an explaination but the decrease in effectiveness of the electric force may be an other. If there are other proofs of the increase in mass it would solve my questionning.
8. ## Relativist mass increase

Analogy wind == electric field What is pushing on the particule to accelerate it ? An electric field. How fast an electric field propagate ? c Do you understand the analogy ?
9. ## Relativist mass increase

Imagine the particule being a sail boat and a wind blowing at c, then there is no way the boat (particule) can go faster than the wind ©. When you put more energy to accelerate the particule and the particule speed doesn't increase in proportion is not because the mass of the particule increase but because the added energy is ineffective. That is why I want to know if there are other proof, because for me this one is not a proof.
10. ## Relativist mass increase

Hi I would like to know if there are proof of the mass increase at speed close c other than the one in the particule accelerator ? Thanks
11. ## How is space expanding ?

H2SO4 To explain the expansion of the universe cosmologistes concluded that the only way to explain that strange phenomena is the bigbang. Like you said the recession is kinetic motion from the big bang. That was a good way to explain the observed motion, until the supernova This thread explain better than me: The accelerating universe - Cosmic inflation For the big crunchs it is happening right now at the center of each galaxies. Other theories explain the redshift in the spectrum of galaxies: gravity redshift, tired light etc where not accepted by the scientific community. Do some google and you will find a lot alternate cosmology. Two years ago I did some search and I found one theory of every thing that looked very logical and was making a lot of senses. I read ther books and the more I was reading the more I was making sense. It start from two postulates and developed a theorical universe that look very similar to the real one from the photon, the atom and molecule and up to the galaxies... Some parts of the development where not very clear and I found some problems in the theory. Other person found the same problem and developped the second version. By clarifying the nature of the photon some of the problems where solved. Now I try to see if the most interesting concept can make sense to others persons who tries to understand the universe. I know this is not an alternate science site, that's why I post here to get a scientific opinion.
12. ## How is space expanding ?

Compare the volume of expanding space to the volume of stationary and contracting space. Stationary space is inside the galaxie cluster where the space does expand. Contracting space are more near the galaxies nucleus. That proportion may suggest that the normal thing is expanding space ? Many scientist told if there was no motion nothing would hapen or something like this. Motion is space over time. Space is only an aspect of that universal motion. Space cannot exist without time and time can not exist without space. Gravity is simply the opposite motion of the expansion. Just some thougth
13. ## Location of Big Bang?

Just try to do the calculations. The only data you will get for the motions of far galaxies (outside the local group) is the redshift. Transversal motion is not apparent so the apparent center will be our local group. If we where in an other far far away galaxy X we would find the center of the expansion at X.
14. ## Relativist mass

From http://homepage.mac.com/ardeshir/EssayOnGeometry.pdf Is what is told in this quote, conform to Relativity ?
15. ## a flat universe?

Here is a good article on the subject. It goes against the curved space of relativity. Does it make sense for you ? Thanks http://www.quackgrass.com/space.html
16. ## The accelerating universe - Cosmic inflation

If it stays constant while space expands, doesn't it mean that dark energy is constanly created from nothing ?
17. ## Gravity model

Scalar motion by definition a motion without direction. Maybe there are other definition, I would like to know. The expansion of the universe is based on the redshift. Other explaination exist in other model like the gravity redshift... Good chance the simpliest explation, the Doppler shift is the good. In that expanding universe there is 3 galaxies A, B and C, 100MLY apart. A will see B receiding in the direction of C. C will see B receding in the direction of A. So B receding in two different direction at the same time and you can extend that to all galaxies outside our local group. Finally B is receding in all directions from all other. I take the jump all directions = no direction . We can say that scalar motion exist. A scalar have magnitude only. A magnitude can be positive or negative. The expansion is positive, gravity is negative. Does it make more sense ? Dark matter is something else. It is used to explain how galaxies and galaxies clusters hold together. The gravity model is not develloped enought to explain that.
18. ## a flat universe?

I like the bubble analogy but more the bubbles in bathtub. The Sloan survey show at large scale a bubble structure big void surronded by galaxies cluster. Other evidence show the web structure. The difference with the analogy is that galaxies occupy a volume, have a thickness occupy 3D or four. I will stop to three. I had a thought about these void that not finally that void. The distant supernovae survey (don't remember the name) showed that the expansion is accelerating. Dark energy was born! Ok my thought: black hole feeding the voids with dark energy or more simply energy causing the acceleration of the expansion. Withe hole a la sauce.
19. ## a flat universe?

I don't know you seem to know a lot more than I about this subject, but my intervention was a reaction to thing like a pancake. Saying the universe is flat doesn't mean that the universe is two dimentional
20. ## a flat universe?

Flat in the cosmologist language doesn't mean flat like a pancake. Flat means that two parallel lines will never meet and remain at the same distance from each other. A positive curvature mean that two parrallel line will meet and a negative curvature mean parallel will never meet and the distance between them will increase. The curvature of the universe, like was said is defined by the quantity of matter in the universe.
21. ## Why do planets form?

Some time ago I thought that the iron dust of the rings can accelerate the process. The proto star magnetic field magnetize this iron and create concertration of iron along the magnetic line. A dust colliding with an other dust must not count only on gravity to agregate. May be relative velocity are hight enought the two dust just fuse? At that scale magnetism is a lot stronger than gravity. I guess in just a few millions years you grow body size from dust to boulder of iron. Not to long after that gravity will play a bigger role. Iron core are suspected at the center of earth and of other planets. I would like to know if the planetary formation model took magnetic and electric forces in consideration? Vladimir: Our sun was form a supernovae remanent, enriched with metal (metal is atomic weigth>2). It is a second generation star. The supernovaes have iron lines in there spectrums. Iron is the end of the fusion process, no more fusion that giveup energy. Nothing to oppose gravity. If big enought it collapse and explode! A first generation star is made from a cloud of H He and a little bit of Li.
22. ## Galaxy diameters

The measurements of galaxy size are calculated with the subtended angle and the distance. The first distance mesurement where done on nearby galaxies having a particular type of stars, the Cepheide. The distance to some Cepheide in our galaxy can be measured by paralaxe (change of apparent position 6 moth appart). The Cepheide stars are variable star, their brigthness go cycle up and down. Knowing there distances they saw that the cycle period is related to the absolute brigthness variation. So by measuring brigthness variation of Cepheide in other galaxie they know the absolute magnitude (brigthness). With the absolute magnitude and the apparent magnitude they calculated the distance. The subtended angle is directly measured. That was a proof that the galaxies where other universe island. We cannot discern individual Cepheide star in distant galaxie. Then Hubble discovered that the spectrum of galaxies where redshifted. The more distant galaxies where the most redshifted. So the redshift is used by extrapolation to mesure the distant of the farest galaxies. The mass of galaxies are evaluated with the surface brigthness and the hydrogen cloud mesure by 21cm H line. If I remember right the evalutation of how mass is needed to hold a galaxie tougether is ten time the visible mass. The force of gravity is proportional to the mass a naive guess would be ten time stronger ???
23. ## Oldest galaxies found

That the age estimated for the solar system. The estimated age of the universe is something like 14 billion years. But for structure that big (the galaxies cluster) to have time to form 9 billions years ago is hard to explain with the bigbang model.
24. ## Speed of Light and Theory of Relativity ?

You would apply the gamma factor to get the relative speed of the space ship. But in that experiment you have two photons are going in opposites directions and I am not sure what would be the gamma factor. Can some one how knows relativity better than me make the calculations ?
25. ## Gravity model

Are you refering to black hole ? In that theory space is quantized so atoms cannot go closer than the Plank length, but atom can look like they are closer than the Plank length because of some kind of time dispersion: atoms look closer in space but they are farther in time... I find this theory have a lot of good idea but I don't know it enought to explain it very well. One of the interesting thing of that theory is the 3 dimentionals aspect of time. They postulate that nothing but motion exist in the universe. Motion is 3 dimentional. Space and time are emergent from motion, so space and time are 3D. There you will get an outline of that theory http://www.rsystem.org/ce/step/index.htm If you can take a look and tell me your opinion on it, tell me if you find some value to it or none.
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