a simple explination of why clocks move faster in spaceby Mad_Gouki Tags: clocks, explination, faster, simple, space 

#1
Dec903, 09:54 PM

P: 15

i am sure that you all know experiments have been done with atomic clocks in outer space and it was found that the atomic clocks that had been in orbit of the earth were further ahead than the ones on earth, does this mean that you travel slightly faster through time while in orbit of the earth?
i was thinking about this one, and i came to a very simple explination. the difference in gravity between the surface of the earth and the gravity experienced in orbit of earth is enough that an atom moving on earth would be slowed slightly because of the forces of gravity. you might say that electrons(maybe protons and neutrons too) arent effected by gravity, but if that is so, then why do atoms fall to the ground if they are denser than air on earth? just pretend, even if you dont think it is true, that the electrons moving around the nucleus of an atom are subject to gravitys pull. now with the decrease in gravity in orbit of the earth(or space for that matter), would it not be reasonable to think that the reason atomic clocks move faster through space is because the atoms have less gravitational resistance, and not that time moves faster in space? in summary: gravity slows atomic movement, which explains why clocks are faster in space. 



#2
Dec1003, 12:23 PM

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Tha case of clocks in orbit is well understood, and the time effects are explained by two factors, one from special relativity and one from general relativiy. I want to emphasize that these effects are not just faster or slower as I will post here but are actually exact calculations of how much faster or slower.
The special relativity effect is because the clocks in orbit are moving rlative to the ground and therefor have a Lorentz transformation applied to them by ground observers that makes them run slower. Like the next one, this is a time effect, not a clock physics effect. The general relativity effect is because the clocks are higher in the Earth's gravity filed and GR says time (not just physical clocks) runs faster high in a gravity field than it does down deeper in a gravity fiels. So this effect tends to make the clocks run faster. You apply these two precise corrections to the clocks and they will tell the same time as a clock at rest on the surface of the Earth. 



#3
Dec1003, 01:17 PM

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And the net result of those two is a clock in orbit runs SLOWER than on the ground.




#4
Dec1303, 11:28 AM

P: 267

a simple explination of why clocks move faster in space
Mad GoukiÕs point is not contradicted by GR.
Time IS the measure of physical systems which may be called clocks. Physical systems must obey the laws of gravity. The gravitational effect on the kinematics of moving bodies is such that: the stressenergy of every particle varies proportional to itÕs position in the field (altitude). The change in a particleÕs stressenergy is directly measurable in itÕs mass and therefore itÕs attraction to and attractive force on, the other particles in the system. This translates to the change in the period of the system (clock). It is not that TIME changes as some mystical (vectorial) force in GR. It is that TIME is the period of physical systems and as physical systems they suffer the effects of gravitational change. But only when compared to a system in a different altitude in the field. It is because we chose to mark time with physical systems that we observe a change. ItÕs only when we hold onto the old notion that time is a linear function regardless of mass and velocity that we refer to it as CHANGED instead of recognizing it is the mass and velocity that we are actually measuring and that is what has changed. In short Mad Gouki has not contradicted GR, he/she has just restated it. 



#5
Dec1303, 12:06 PM

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No, they haven't just restated GR. They rely on the force of gravity "experienced" by the clock, thus the time rate would vary by the local force of gravity. This is not what GR predicts. The formula for gravitational time dilation is: [tex] T_{1}=\frac{T_{0}}{ \sqrt{1\frac{2GM}{Rc^2}}} [/tex] The local strength of the gravitational field is directly porpotional to the local acceleration due to gravity or: [tex]g=\frac{GM}{R^2}[/tex] These do not give the same results. For example, the surface gravity of Uranus is actually less that that of Earth's (about 90%) If it is the local force of gravity(and The clock's physical response to it) that causes the time dilation, then a clock sitting o the Surface of Uranus would run faster than one sitting on the surface of the Earth. If, however, you plug the relative masses and radii of Earth and Uranus into the Time dilation formula, you find that GR predicts that a clock will run slower on the Surface of Uranus than on the Earth. All of the observations done on the effect of gravity on clocks show that the trend follows that predicted by GR, and thus it is not due to any physical effect gravity has on the mechanism or material of the clock. 



#6
Dec1303, 02:02 PM

P: 2

yad yada guys?
im thinking we'r all wrong.. its that"curvature " of space.. ( not Gravity . that's making comparitve measurements.. of what we, call "time" seem to process at differing rates.. seems less likely as i think on it? gravity works on "fields" ? lagre scales.. not on individual point mass in the field.. the slowin of "time is a function of dispalcment of the field? the curvature, or pullin on matter.. 



#7
Dec1403, 01:06 PM

P: 267

Uranus is about 14 times the mass of earth but only 4 times the diameter.
What does this mean? Do we account for the curvature of space when we say itÕs diameter is 4 times that of Earth? Does the curvature of itÕs space STOP at the point we call the surface? Is the space between itÕs particles not astronomically greater than the space occupied by itÕs particles? The ÒcurvatureÓ of space on the surface of Uranus is greater than the curvature of space on the EarthÕs surface(when we hold mass as unity). Relative to a clock on the EarthÕs surface, a clock on the surface of Uranus will run slower. If the curvature of space was directly proportional to the gravitational attraction between masses at their surfaces, the density of mass would be consistent in all things in the universe. Yes, a 100 pound object on Earth would weigh 90 pounds on Uranus. But a 100 pound object on Earth occupies either less time or more space (depending on which reference you chose as unity) than they do on Uranus. You seem to be implying that the shape of space has no physical effect on the bodies that occupy it. The dimensions of physics are the variables of GR: spacetimemass. GR does not state a preferred ontology. Space/time is an extension of mass. The only contradiction that can be implied by Mad GoukiÕs statement is seen by those who choose a preferred metaphysical framework that holds mass and space as a priority over time. To do so is a matter of philosophical preference. But it is not in any way justified by GR. And as a philosophical preference it fails to recognize time as an extension of mass and space. 



#8
Dec1403, 03:34 PM

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Originally posted by Chrisc
Uranus is about 14 times the mass of earth but only 4 times the diameter. What does this mean? The volume of a sphere is [tex]\frac {4\pi}{3} r^2[/tex] or about 4.2r squared. so if the radius of Urnus is four times that of Earth then its volume will be over 16 times Earth's. If it is then only 14 times as massive, that means that Uranus is less dense than Earth, on the average, which is reasonable since it is a gas giant. Do we account for the curvature of space when we say itÕs diameter is 4 times that of Earth? It's the mass, not the radius, that comes into the GR formula (Schwartzschild metric). Does the curvature of itÕs space STOP at the point we call the surface? No Is the space between itÕs particles not astronomically greater than the space occupied by itÕs particles? True everywhere that matter is. The ÒcurvatureÓ of space on the surface of Uranus is greater than the curvature of space on the EarthÕs surface(when we hold mass as unity). Relative to a clock on the EarthÕs surface, a clock on the surface of Uranus will run slower. True. If the curvature of space was directly proportional to the gravitational attraction between masses at their surfaces, the density of mass would be consistent in all things in the universe. This claim is not clear to me. Gravity is calculated as if the mass were concentrated at the center of gravity. For spheres in Newtonian gravity this is exact (as shown by Newton). For GR it is a close enough approximation. Yes, a 100 pound object on Earth would weigh 90 pounds on Uranus. But a 100 pound object on Earth occupies either less time or more space (depending on which reference you chose as unity) than they do on Uranus. No. That is in fact exactly what GR does predict. Where did you get this? It's false. You seem to be implying that the shape of space has no physical effect on the bodies that occupy it. The dimensions of physics are the variables of GR: spacetimemass. GR does not state a preferred ontology. Space/time is an extension of mass. The variables of GR are spacetime, curvature, energymomentumstress. Mass is just one form of that. Many things can cause the spacetime metric to vary. Mass is one, but light and gravity waves are others. The only contradiction that can be implied by Mad GoukiÕs statement is seen by those who choose a preferred metaphysical framework that holds mass and space as a priority over time. To do so is a matter of philosophical preference. But it is not in any way justified by GR. And as a philosophical preference it fails to recognize time as an extension of mass and space. Bah. There is no such metaphysics. Mass is a form of energy. energy in flux (momentum and stress) is neither prior to nor subsequent to spacetime, but coordinate with it, through Einstein's equations. 



#9
Dec1403, 08:42 PM

P: 267

But then ... Have you ever thought about measuring the radius of a black hole? It is impossible to define, just as impossible as finding a place in the universe void of gravity. Momentum is energy as is stress. Energy is mass and mass is space/time. It is only the mass of a photon that allows light to effect a change in space/time. A gravity wave is a change in space/time. What you are saying is the only thing other than mass that effects change in space/time is a change in space/time. Einstein said it. He proved it. It seems everyone is afraid to accept it. Energy is not a mystical thing. It is displacement over time... or space/time. He also said, and proved through GR: Òspace/time is an extension of massÓ So what more do we need? Mass is space/time unextened. Extend it and you will find astronomical quantities of space/time. So the quantity of time, mass and space we choose to define in any system is relative to the time, mass and space we choose as unity. So although Mad Gouki may have meant that clocks were slowed due to gravitational drag, which would not account for the dilation, he said it was due to their altitude in a gravitational field. And in that he is right. Not because TIME is an independent function of a system. Because TIME is one axis of a continuum that includes space and mass. 



#10
Dec1403, 09:46 PM

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Energy comes in many forms, motion, light, and gravity waves have no mass but they are just as much forms of energy as mass is. True that energy CAN be converted into mass, but nowhere near all of it is. And it is just as true that mass can be converted into some other form of energy. The energy momentum stress tensor has sixteen components. Because it's symmetric only ten of them are independent. One of those components is energy, three of them (six if you count symmetry) are the components of thee dimensional momentum, and the remaining six independent components are the space rate of change of momentum (stress). Notice something that wasn't in there? That's right: MASS. All of the rest of your massmytique falls apart when you realize that mass isn't the beall and endall of GR. 



#11
Dec2003, 08:40 AM

P: 267

What GR defines is the geometry of space/time in the presence of mass.
That is not to say space/time has a geometry in the absence of mass any more than we can say that space exists without the presence of gravity as they are one and the same. Einstein was very careful in stating MATTER as the unknown NOT MASS, as GR is fundamentally a geometrical model describing the translatory relation of mass and space/time. Physicists have spent the last ninety years in search of a model that holds to the experimental evidence of QT without contradicting GR. The best to date, is stringtheory. Although the supersymmetry of string theory unfolds to GR, it does little to extend our understanding of the nature of mass. It relies on the beauty of mathematics to take us into a conceptual model of dimensions beyond comprehension. And at the bottom is a metaphysical model of stringlike dimensions that hold self consistency in the fact that we can not comprehend it beyond the mathematical rules that define it. Energy is a scalar quantity with dimensions [mass X length^2/time^2] that possesses the properties of mass. It is true there are many FORMs of energy. But they are all, ultimately distillable to the equation above. If you think you can give an example of energy in the absence of mass you will find it is only when describing a translation from or to mass. Which again shows us that mass is energy and energy is the translational relationship (tensor) of space/time/mass. To say mass is energy and energy is the relational change of space, time and mass sounds like a circular argument because it is. Einstein knew it but what he realized was the circularity was manifest in our inability to understand a more complete continuum. The third mass is already understood to be part of a greater unifying continuum. We have just not found the means to fully incorporate it in a manner that survives the scrutiny of QT. So my massmystique does not fall apart unless you do not realize what GR says. 



#12
Dec2003, 09:56 AM

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So do you also assert that light is "matter" that has "mass"?




#13
Dec2103, 06:12 PM

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dude, you are such a dork 



#14
Dec2103, 08:25 PM

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Watch your language.
It was a genuine question. Light gravitates in general relativity, this was proven by observation in 1919. But light has no mass. It has momentum and energy, but it has no mass. All its momentum and energy come from its frequency, the higher the frequency the higher the momentum and energy. All of this is experimentally proven fact. How does your theory handle these facts? 



#15
Dec2103, 10:22 PM

P: 267

No, light is not matter and it cannot be said to have mass except when it is mistaken as, or modeled as a particle.
How my theory (which is no more than an indepth consideration of GR in first principles) handles these facts is quite simple, but I think you will have trouble considering it. Light is perceived in itÕs ability to displace other particles which themselves are only perceived when the effect of their displacement can be measured in macro systems. This transition from micro to macro is the point at which our interpretation has failed. The quantum action. QT is a model that was necessary to hold our physical laws together under our failure to understand time. Light is a displacement of time. As such it demonstrates all the properties we attribute to photons. It has a magnitude of displacement and a frequency of displacement. As a displacement of time it should be clear why it is a constant. To answer you question directly, light, as a displacement of time has momentum as itÕs displacement propagates to a system where we measure the spatial displacement as a function of time. None of this is more than semantics until you realize what time is. YouÕve probably heard those that first grasp GR exclaim ÒThe metric is the FieldÓ. This is extremely significant in both the understanding of GR and how Einstein thought his way to it. It is also extremely important in understanding timeÕs place in the dynamics of GR. Time marches on. It has become elastic as part of the continuum, but it is still seen as a vectorial ontology that signifies change and has a direction toward entropy. What I have done is to put it fully into the dynamics of EinsteinÕs metric. Time is the process of space condensing to mass. I will leave you with this to consider. Please consider it well before responding. Once you get over calling me a looney, I hope you will consider it again. It is sublime. It scares the hell out of most people who begin to grasp it. But it does work and I believe it will be published soon 



#16
Dec2203, 12:24 AM

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i was talking about one thing, gravity, and its affect on atoms, and you changed to light...
please stay on topic 



#17
Dec2203, 08:19 AM

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What exactly is time? Time is defined as "The interval between two events". So, the speed at which time passes is then all relative to how time passes within different systems. Since clocks move faster in space, whatever the reason, the particals of the clock would be moving equivalently faster, would they not? So, relative to the rest of that clock, a partical of it would experience no change in time, but the observations from a system such as Earth where partical interactions are slower (Again, whatever the reason), it would seem as though everything as a whole is faster in the higher reaches of the gravitational field.
Your theory on gravity's strength at altitudes makes sense, but there are the numbers. But what is it that would then cause these effects if it was only based upon curvature, distance from gravitational center, Etc, and the resistance of gravity was thrown out? Wouldn't that make a difference? 



#18
Dec2203, 10:18 AM

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