Andre Lefebvre Posted July 11, 2015 Author Posted July 11, 2015 Mordred; I've got a question for you: is it possible to get the answer to this problem: (10-35 /2)2 x 3.1416 =
Strange Posted July 11, 2015 Posted July 11, 2015 Mordred; I've got a question for you: is it possible to get the answer to this problem: (10-35 /2)2 x 3.1416 = Typing (10^-35 /2)^2 x 3.1416 = into Google or Wolfram Alpha gives you the answer: http://www.wolframalpha.com/input/?i=%2810^-35+%2F2%29^2+x+3.1416+%3D = 7.854x10-71
Andre Lefebvre Posted July 11, 2015 Author Posted July 11, 2015 Thank you Strange; but How can (10-35 /2) becomes (1/1035 x 2)?
Andre Lefebvre Posted July 14, 2015 Author Posted July 14, 2015 (edited) No answer; no problem. More informations delivered by Planck satellite photos: Since Planck satellite photos are the latest “facts” (and not theories) we have on the early universe, I feel that I have to concentrate on everything it can tell me. So I came back to it and this is what I went through: Planck scientists told us that where the temperature was higher (red spots), there was a movement of “focusing” that we can interpret as an “effect of gravity”, and where were the colder spots (blue), there was an “effect of dispersion” which is the movement of the expansion. So I choose a section of the photo where we have a maximum of both “effects” and I draw arrows to show the respective movement in each spots. One thing is quite surprising. Even if the movements are contrary to each other, the “structure” of both types of temperature, is the same. Both figures show more intensity in the middle of their “form”. This is perfectly understandable since where you have the focussing effect, the red middle increases in density and where you have dispersion effect, the blue middle dilutes its intensity. The problem appears when you start thinking of what is actually the opinion of scientists who say that the “gravity” manifests itself in the whole of space-time. Which means that in the blue spot that dilutes its density, there is a hidden manifestation of the red spot and behind the red spot there is a manifestation of the blue spot. Mathematic equations explain this as a possibility and scientists consider it as a “fact”. But what we seen here is not the case at all. What we see is that the blue spot is completely independent from the red spot and vice-versa. If we consider each spot as having their own metric of space-time, we have the red spots showing a decreasing metric and the blue spot showing an increasing metric. And it’s impossible to have decreasing and increasing metrics in the same volume of space-time. If we really had a competition between those two “effects” in the metric of a volume of space-time, it would mean that those effects appeared in the universe before its metric appeared; which is completely nonsense. The only explanation that makes sense is that gravity in the red spots has no effect whatsoever on the expansion of the blue spots. In other words, gravity is not “universal” just as expansion is not “universal”. Where we have gravity we don’t have expansion and where we have expansion, we don’t have gravity. So gravity is “local” and, so is expansion. This also brings another information. The red spots appeared in our universe after the blue spots, since at the big bang there was only a manifestation of radiative movement without any matter; so without any gravity which means without any space-time deformations. It also state that when gravitation appeared, it did it bringing its own volume of space-time that was added to the actual space-time in expansion. Which resulted in the inflation period caused by that “added” volume at 10-36 sec and explains why inflation didn’t disturb expansion; it didn’t apply to the same volume of space-time. The result however is that where there’s expansion, that volume of space-time will expand exponentially faster than where there is gravity. Which will end by distributing matter, on a picture after 13 billion years of expansion, in filaments in regard of the big “bubbles” of space-time expanding where there’s no gravity. Consequently, matter distribution in filaments is not a consequence of “gravity disturbances” but a consequence of the more rapid expansion of the volumes of “empty” space-time. And the regrouping of galaxies in clusters and super clusters is a consequence of the distribution of galaxies in filaments. Filaments are subjected to expansion but only from the level of galaxies cluster inclusively. From the level of galaxy down to the level of atom, expansion is absent. So, because the volume of space-time in filaments subjected to expansion is so small, in the overall picture, the rapidity of expansion of “empty” space-time, makes them appear as not expanding at all and even seem “collapsing”. But that is evidently a kind of optical illusion. Furthermore space-time is in majotity "flat" because the "bubbles" of "empty" space-time are extremely more voluminous than the filaments where gravity stands. Edited July 14, 2015 by Andre Lefebvre
Mordred Posted July 15, 2015 Posted July 15, 2015 (edited) Sorry I didn't answer your math question. I was busy and when I saw it figured you would have googled a math review. Anyways that being said this last post you still seem to be having some trouble in how expansion works. Take the average energy/mass density of the cosmological constant (negative vaccuum.) The average energy density is 6.7*10^-10 joules/m^3. It's extremely weak. So weak that locally gravity and gravitational bound objects can easily overcome the cosmological constant. Where the cosmological constant has the most influence is where there is a significant void between large scale structures. So yes both effects can be present in the exact same region, it's just the weaker influence is overpowered. Here is a useful analogy. Take a rock and suspend it. The Earths gravity attracts the rock yet the strong force binding the rock is stronger. So the rock maintains its shape. Increase the gravity (say a BH) the rock undergoes spagetification. Gravity vs the cosmological constant is the same scenario. Edited July 15, 2015 by Mordred
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 (edited) Thanks for the information Mordred. I'll check on it. If you look at: https://en.wikipedia.org/wiki/Cosmological_constant You sure sound more sure of the fact, than this article. As for the suspended rock, Earth doesn't attract it. By suspending it, you're preventing it to follow the topology of the deformation of the geometry of the space-time around the Earth down to its center of gravity. If you let it go, it's going to try to reach that center of gravity and push on the ground trying it. Furthermore, if it falls in a BH, it's only a theory that it would undergo spagetification. There's no pull action coming from the black hole. Again, we're facing a space-time deformation even if it is a maximum one. The “pull action” is only an appearance; in fact the movement toward the center of gravity is induced by the direction given by the deformed space-time toward that center. Right with this problem you can see, how a wrong notion as a base for interpretation can mislead. There is no “attraction” of masses in GR. Edited July 15, 2015 by Andre Lefebvre
Mordred Posted July 15, 2015 Posted July 15, 2015 (edited) Thanks for the information Mordred. I'll check on it. If you look at: https://en.wikipedia.org/wiki/Cosmological_constant You sure sound more sure of the fact, than this article. As for the suspended rock, Earth doesn't attract it. By suspending it, you're preventing it to follow the topology of the deformation of the geometry of the space-time around the Earth down to its center of gravity. If you let it go, it's going to try to reach that center of gravity and push on the ground trying it. Furthermore, if it falls in a BH, it's only a theory that it would undergo spagetification. There's no pull action coming from the black hole. Again, we're facing a space-time deformation even if it is a maximum one. The pull action is only an appearance; in fact the movement toward the center of gravity is induced by the direction given by the deformed space-time toward that center. Right with this problem you can see, how a wrong notion as a base for interpretation can mislead. There is no attraction of masses in GR. However you wish to define how gravity attracts as either due to force or spacetime curvature is up to you. Either way gravity attracts mass in that mass moves to sources of mass. Even if the cause of gravity is due strictly to space time curvature. The mathematics still work for Newtons universal laws of gravity. For everyday applications. There is nothing wrong in calling this a force. Particularly since Newtons laws of inertia can still be applied. Your objection boils down to mere semantics. And yes I am confident of my answer. I already posted to you the ideal gas law applications including the acceleration equation in the FLRW metric. You once stated you have a copy of Barbers Rydens "Introductory to Cosmology". Please review the section. "Learn to love Lambda" Edited July 15, 2015 by Mordred
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 Even if the cause of gravity is due strictly to space time curvature. The mathematics still work for Newtons universal laws of gravity. For everyday applications. Everyday applications like in a BH. Your objection boils down to mere semantics. Mordred, you call semantics the fact that since there's no attraction, the object that gets into a deformation must have its own peculiar movement to get to the center of gravity? What can I tell you?
Mordred Posted July 15, 2015 Posted July 15, 2015 (edited) (PS don't completely trust wiki links. The anti gravity description on that link is misleading). It's anti gravity like. However works via negative vacuum w=-1 [latex]w=\frac{\rho}{p}[/latex] Everyday applications like in a BH. Mordred, you call semantics the fact that since there's no attraction, the object that gets into a deformation must have its own peculiar movement to get to the center of gravity? What can I tell you? The influence whatever the cause still boils down to sources of gravity causes movement (attraction). There is no source of anti gravity. Gravity attracts only. Lambda is oft misrepresented by stating its anti gravity like. This does not mean the same thing as anti gravity. So it is semantics. GR describes the cause of this movement due to space time deformation. Newton due to force. In both cases objects move towards each other due to gravity. The source of gravity in both cases has the mass relation included. An object doesn't need its own peculiar movement. You place a ball at rest on a table. You can still measure its weight even though it is at rest. ( where is the movement?) Gravity is still influencing that ball even though it is at rest. That should tell you there is still an attraction even for objects at rest. GR and Newton both have different explanations for this but both GR and Newton recognize gravity attracts. The main difference is "Is that attraction due to curvature geometry only ? (GR) or is there a force carrying gravitational boson? Graviton. Neither answer is ruled out. GR cannot quantize gravity at the quantum regime. Single particle interactions gravity becomes immeasurable. Simply too weak particle to particle. We cannot generate nearly enough energy to create a graviton. So we still haven't found any spin 2 particles. If we do it's most likely the graviton as gravity follows spin 2 statistics. Hopefully one day quantum gravity solves that quantizing problem. Till then you can accurately describe gravity as a force or due to curvature. Either or mass does attract mass via one of the two mentioned processes (Possibly even both) In either case mass is simply "resistance to inertia changes" any Form of binding energy can cause mass. The strong force is simply the most common source. The Higgs field only affects certain particles. Edited July 15, 2015 by Mordred
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 the cause still boils down to sources of gravity causes movement (attraction) So you don't make anymore difference between acceleration and movement do you? There is no source of anti gravity. Gravity attracts only. There we agree. Since deformation of space-time is the source of gravity, it's impossible to imagine another kind of deformation for antigravity. The source of gravity in both cases has the mass relation included. Not for GR. For GR the source is the deformation of space-time. For Newton it's a law thas as no sense stating that masses attracts themselves. There's no way to change those facts. An object doesn't need its own peculiar movement. You place a ball at rest on a table. A ball is not at rest on a table; it's prevented from going to the center of gravity of the Earth (to make it simple). You can still measure its weight even though it is at rest. Its weight is what pisshes on the table and if you eliminate the table it will push forward until it hits the ground and tjen keep on pusshing on the ground. It wants to get to the center of gravity of the Earth. It's not hard to understand. where is the movement? The table is blocking it. Gravity is still influencing that ball even though it is at rest Gravity is the direction it tells the ball to follow, in order to get to the center of gravity. Gravity doesn't do anything else than being a direction signalisation. That should tell you there is still an attraction even for objects at rest. 1) The ball is not ar rest; it's blocked. 2) There's no attraction involved. but both GR and Newton recognize gravity attracts. Newton is the one who imagined "attraction" of the masses. Einstein said it wasn't the case, since gravitayion was only a "conseuqence" of space-time deformation. There is no "force" of attraction. Gravity is "passive; not "active".
Mordred Posted July 15, 2015 Posted July 15, 2015 Gravity only directly influences bodies and particles with mass. Hence photons with no rest mass follows null geodesics. While particles with mass following time like geodesics. There we agree. Since deformation of space-time is the source of gravity, . You can't have space time deformation without energy. Energy is equivelent to mass via e=mc^2. The problem is you keep thinking mass implies matter. It doesn't. Any form of energy even. Gravitation wave can cause gravity via resistance to inertia=mass. The problem you seem to have is that you fight against the term mass. Yet the term itself doesn't mean due to matter. It means resistance to inertia change.
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 The problem is you keep thinking mass implies matter. It doesn't. You must be kidding. I been saying all the time that mass didn't imply matter and that's why I always mentioned mass energy. Gravitation wave can cause gravity via resistance to inertia=mass. Has anybody ever seen gravitation waves? The problem you seem to have is that you fight against the term mass. I think that you don't want to understand. I fight against the notion that quantity of matter (newtons mass) attract each other. And thinking that gives the result that we just saw two posts ago. It means resistance to inertia change. Resistance to change IS inertia.
Mordred Posted July 15, 2015 Posted July 15, 2015 (edited) Here you can see how GR affects massless photons differently than massive particles. "massless particles like the photon instead follow null geodesics (replace −1 with zero on the right-hand side of the last equation). " https://en.m.wikipedia.org/wiki/Geodesics_in_general_relativity Whether or not you wish to call gravity a curvature influence only or a force is entirely up to you. However GR doesn't necessarily invalidate the graviton. It's still incomplete in that regard. Resistance to change IS inertia. Wrong . a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force. Mass is resistance to change in inertia. Not inertia itself. Edited July 15, 2015 by Mordred
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 massless particles like the photon instead follow null geodesics That's new to me (at least) So photons don't follow the curvature of space-time in a deformation?<< However GR doesn't necessarily invalidate the graviton. It's still incomplete in that regard. So until we prove the existence of the graviton, vector of a force that GR say doesn't exist, GR wil be incomplete. That's logic.
Mordred Posted July 15, 2015 Posted July 15, 2015 (edited) That's new to me (at least) So photons don't follow the curvature of space-time in a deformation?<< So until we prove the existence of the graviton, vector of a force that GR say doesn't exist, GR wil be incomplete. That's logic. In science any theory until proven false is viable. Get used to it. Its more accurate to state until we can quantize gravity to particle to particle interactions. Or prove this to be impossible. All forms of geodesics is a space time curvature path. Just not the same path. Three geodesics are involved. Null, spacelike and time like. Particles with mass follow time like specifically free falling particles. http://www.physics.usyd.edu.au/~luke/research/masters-geodesics.pdf Key note there is an excellent line in this article. "Energy=curvature" Edited July 15, 2015 by Mordred
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 In science any theory until proven false is viable. Too bad Einstein isn't there anymore so you could tell him that. Or, at least, try to convince him. I've got to go. We'll see tomorrow. Take care.
Mordred Posted July 15, 2015 Posted July 15, 2015 (edited) Too bad Einstein isn't there anymore so you could tell him that. Or, at least, try to convince him. I've got to go. We'll see tomorrow. Take care. Einstein would have known that himself. It's part of the scientific method.Here is a translated quote from one of his papers. Keep in mind he is specifically stating in Euclidean geometry (flat). Newtonian physics is highly accurate, but only valid until you have space time geometry changes. "As is well known, the fundamental law of the mechanics of Galilei-Newton, which is known as the law of inertia, can be stated thus: A body removed sufficiently far from other bodies continues in a state of rest or of uniform motion in a straight line. This law not only says something about the motion of the bodies, but it also indicates the reference-bodies or systems of coordinates, permissible in mechanics, which can be used in mechanical description. The visible fixed stars are bodies for which the law of inertia certainly holds to a high degree of approximation. Now if we use a system of co-ordinates which is rigidly attached to the earth, then, relative to this system, every fixed star describes a circle of immense radius in the course of an astronomical day, a result which is opposed to the statement of the law of inertia. So that if we adhere to this law we must refer these motions only to systems of coordinates relative to which the fixed stars do not move in a circle. A system of co-ordinates of which the state of motion is such that the law of inertia holds relative to it is called a " Galileian system of co-ordinates." The laws of the mechanics of Galflei-Newton can be regarded as valid only for a Galileian system of co-ordinates." http://www.marxists.org/reference/archive/einstein/works/1910s/relative/relativity.pdf An authorized reprint of Einsteins Special relativity paper Here is an excellent paper on the difficulty in quantifying gravity. On particular GR to QM. http://arxiv.org/abs/gr-qc/0004005 ( by the way your arguments are getting better ) just needs polishing. As well as recognizing that regardless of how robust and accurate GR is. It's not the final chapter on gravity. Edited July 15, 2015 by Mordred
ajb Posted July 15, 2015 Posted July 15, 2015 So until we prove the existence of the graviton, vector of a force that GR say doesn't exist, GR wil be incomplete. That's logic. Classical general relativity itself does not say anything about gravitons, just as classical electrodynamics does not say anything about photons. The standard quantisation methods that work for electrodynamics fail for general relativity. However, we can still discuss quantum general relativity as an effective theory and describe gravitons on that context.
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 Thank you ajb. Coming back on one argument: Even if the cause of gravity is due strictly to space time curvature. The mathematics still work for Newtons universal laws of gravity. For everyday applications. That argument is the equivalent as someone using table salt whitout knowing that salt is made by evaporation of brine. He can use it and think that salt was made by a manufacture called Sifto Canada corporation. But he can't explain the real facts about how salt is made.
Strange Posted July 15, 2015 Posted July 15, 2015 That argument is the equivalent as someone using table salt whitout knowing that salt is made by evaporation of brine. He can use it and think that salt was made by a manufacture called Sifto Canada corporation. But he can't explain the real facts about how salt is made. I'm not sure that is a good analogy. Your example is equivalent to someone who knows that gravity exists, but doesn't know anything quantitative about its causes or effects. But they might study science at school and they will learn that salt is a compound of Na and Cl (they might even learn about ionic and covalent bonds). Equivalently, they will also learn about Newton's theory of gravitation. If they do not go any further in science, those will be the theories and level of understanding they are left with. (until they forget it all!) Nothing wrong with that, perfectly good enough for everyday use. If they go on to university, then they might study physical chemistry and all about electron orbitals, Pi bonds, etc. Similarly they might learn about Einstein's theory of gravity. If they are foolish, they might think these are the "truth". But they are more likely to realise that, having been taught one set of "wrong" theories at school, these new theories are likely to be "wrong" as well. They may go on and study quantum theory, and understand why bonding orbitals exist. They may go on and study (or invent) the theories that explain why Einstein's theory works. They will, of course, realise that any such deeper theory is just as "wrong" as the others.
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 Resistance to change IS inertia. Wrong . a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force. Mass is resistance to change in inertia. Not inertia itself. So you're saying that resistance to change in inertia is mass. Since inertia is being at rest or in uniform motion, you mean that resisting being at rest or uniform motion is mass. Then mass is the energy that eliminates that "resisting being at rest". This energy is applied to an object to resist "being at rest" or to "increase its motion". That's the work needed to accelerate a body of a given mass from rest or change its velocity. That energy is called kinetic energy if I remember right. So E = Mc2 means that E is kinetic energy just as mass is when "not at rest", because multiplied by "c2". Since nothing is never at rest, then kinetic energy is the work to change the velocity of kinetic energy. They will, of course, realise that any such deeper theory is just as "wrong" as the others. And if they were told at the start that salt was made by evaporation of brine, they would know what a theory is and not think it "true" whitout understanding the source.
Mordred Posted July 15, 2015 Posted July 15, 2015 Is it? We're talking about Newtons laws of inertia. In Euclidean geometry these three laws does an excellent approximation. It's currently used by engineers mechanics etc far more than GR. Works well for everyday applications. The main difference between the two comes into play via geometry/coordinate change. In curved space time those laws still apply, just under different coordinates. For example Newtons laws of inertia works under the Three Geodesic transformations. Those laws still hold true. I. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it. II. The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors in this law the direction of the force vector is the same as the direction of the acceleration vector. III for every action there is an equal and opposite reaction. your objection is based on the use of the term force. "In physics, a force is any interaction that tends to change the motion of an object. In other words, a force can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate. Force can also be described by intuitive concepts such as a push or a pull." Space time geometry certainly counts as an interaction. It certainly tends to change the motion of objects. By any definition space time fits the bill of a force.
Strange Posted July 15, 2015 Posted July 15, 2015 Since inertia is being at rest or in uniform motion That is not what inertia means. Then mass is the energy that eliminates that "resisting being at rest". No, because the amount of energy needed to "resist being at rest" (i.e. to accelerate something) is not a fixed quantity; it depends on the final velocity. So E = Mc2 means that E is kinetic energy No, because M is the rest mass. Kinetic energy is separate from (or additional to) this.
Andre Lefebvre Posted July 15, 2015 Author Posted July 15, 2015 (edited) III for every action there is an equal and opposite reaction. So the more I push on the ground, the more the Earth pushes back. Geez that's anti gravity!!! Those three laws are needed for mathematics not for the universe or even for understanding. Space-time geometry is enough for the universe to be as it is and to have evolve since the Big bang. And if you start with that sole fact, you'll be able to understand everything whitout having to justifiy every move and opinion of humans since they first cracked a nut.. The pushing back of a wall on my hands doesn't mean anything. The resistance of a wall to my pushing on it, is enough for me to understand the situation. That's compared to everyday use. And if I think that when I'm not pushing the wall, it's attracting me, well, maybe I'll run away to evade its "action". If I push enough on the wall it might break and fall on me. It won't be because it is defending itself; but I could think it is. And thinking that way will not make me do science. We both know that the wall doesn't "act"; it's passive. Just as gravity. So why see it as "pushing back when pushed? Since inertia is being at rest or in uniform motion That is not what inertia means. Why don't you say what it means then! http://www.thefreedictionary.com/inertia Then mass is the energy that eliminates that "resisting being at rest". No, because the amount of energy needed to "resist being at rest" (i.e. to accelerate something) is not a fixed quantity; it depends on the final velocity. And mass is a fixed quantity? Specially when accelerating? No, because M is the rest mass. Kinetic energy is separate from (or additional to) this. M is the rest mass; but what is c2applied to it to equal E? Edited July 15, 2015 by Andre Lefebvre
Strange Posted July 15, 2015 Posted July 15, 2015 So the more I push on the ground, the more the Earth pushes back. Geez that's anti gravity!!! It might be if the ground pushed back more than you push on it. At it is, it pushes back with exactly the same force. Why don't you say what it means then! http://www.thefreedictionary.com/inertia Yep. That seems like a reasonable definition. (Clearly, totally different from yours.) And mass is a fixed quantity? Specially when accelerating? Yes. Mass is rest mass and does not change. M is the rest mass; but what is c2applied to it to equal E? It is a conversion factor required because we use random wacky units like seconds, kilograms and metres.
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