Yeah marcus.. This is exactly my point!! I have posted above!!
Why two mass attracts each other?
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Yeah marcus.. This is exactly my point!! I have posted above!!
But one thing i couldn't understand is still why do you say that it is measured by clocks?
Value of proper time changes due to motion or path taken by the clock. So i think clocks would measure different coordinate time and when they calculated invariant interval,they will get this changed value of proper time.
And i think that clocks measure coordinate time because clocks are synchronized to coordinate time.. SO how can clocks measure proper time?
Value of proper time changes due to motion or path taken by the clock. So i think clocks would measure different coordinate time and when they calculated invariant interval,they will get this changed value of proper time.
And i think that clocks measure coordinate time because clocks are synchronized to coordinate time.. SO how can clocks measure proper time?
Markus Hanke
Registered Senior Member
What you are quoting there is for two objects moving under the influence of an external gravitational field. What I was referring to was two initially stationary objects under the influence of their own gravity only.
Of course, if you have two objects on parallel trajectories moving into an external field, then their geodesic deviation will depend on the initial parameters of their trajectories, as well as on the geometry of the field.
First answer to the question. How can you show acceleration can also be indistinguishable from the repulsive force?
There is no need to go to geometry of space-time as Einstein's Equivalence principle is based on it.
But not all concepts can be visualized using Einstein's experiment to show equivalence principle and there we need space-time geometry.
But the question that you asked can be explained in terms of how Einstein proved his equivalence principle.
Markus Hanke
Registered Senior Member
In Special Relativity, what clocks which pass through the same two events measure does not depend on the path taken, so long as no acceleration is involved. I think you are confusing proper time and coordinate time - it is proper time that is measured by clocks, whereas coordinate time can not generally be measured. This is how it is defined. Refer also to the first few sentences in the Wiki article on "Proper time" ( quote ) :
"In relativity, proper time is the elapsed time between two events as measured by a clock that passes through both events. The proper time depends not only on the events but also on the motion of the clock between the events. An accelerated clock will measure a smaller elapsed time between two events than that measured by a non-accelerated (inertial) clock between the same two events. The twin paradox is an example of this effect.
(...)
By contrast, coordinate time is the time between two events as measured by a distant observer using that observer's own method of assigning a time to an event. In the special case of an inertial observer in special relativity, the time is measured using the observer's clock and the observer's definition of simultaneity."
Well, Einstein's Equivalence principle does say the equality of inertial mass and gravitational mass.. It is an important concept but no where in the quote Wikipedia shows enough details.
Go to this: http://www.marxists.org/reference/archive/einstein/works/1910s/relative/relativity.pdf
Read Full second part of General Relativity.
But make sure you understand the full part of Spacial Theory Of Relativity too.
Markus Hanke
Registered Senior Member
From wikio you mean this wiki quote?
What he means is that, without reference to some outside point, you cannot distinguish between local acceleration and the presence of a gravitational field. They are physically equivalent in every way.
Yes. i know the following statement. This is actually what i meant by quote. the only thing i said is that inertial observers have same proper time because they all follow same path...
yes. coordinate time is what an observer wants in order to measure distant events. i know that. In order to measure distinct events,he must synchronize another clock so that he can measure that distant event too..
Coordinate time can also be said as common time to both clocks which are spatially separated...
Aren't these correct? Still why do you think that i am confusing?
"Repulsive Force" is non-accelerating because of the "distance" factor. This factor does not decide the direction of a force.
Wiensteins New TOE( 12 - 12 Symmetry ) and Womb contraction > Cervical Dilation
All this "time dilation" "length contraction" talk got me to thinking about "contraction"( pulling-in ) of the womb too induce a dilation( expanding-out ) of the cervix to allow baby exit the womb. This is a pulling-in force that leads to a pushing-out force.
Maybe I stated this in reference to gravity in another post. Gravity is a pulling-in( mass-attractive ) force--- see non-observed graviton :--) ---and as a result of gravities pulling-in, there is a resultant pushing-out reaction called dark energy or cosmological constant.
If I recall correctly, the new news out regarding Wienstiens TOEeveything, is that there is not repulsive, cosmological constant ergo no dark energy. He apparently believes that the observed Universe we see is just a flat part of a greater Universe, and this flatness is what cause the appearance of a cosmological constant or dark energy.
So it appears to me, that, just as some believe that gravity is purely a geometrical subcataory of mathematics, I believe that, the cosmological constant is a resultant of spactime contraction, and similar to the situation with the fetus/baby exiting womb to become independent baby.
I'm curious to see how Wienstien handles the constancy of speed-of-radiation and gravity( mass-attraction ) as a force of nature or just mathematical subcategory of geometry.
My feeling is that there exists tubes of nature that feed into larger containment chambers--- ex polyhedral, spherical whatever ---that then have exit tubes/pathways canals etc.....on both the macro, medio, micro and ultra-micro scales of existence.
If mass-attraction did not exist, Universe would not exist. Time/accelearation(?) dilation and space/length contraction?
How do we simplify this for the common human? If we say that speed-of-radiation is like time standing still--- see Brian Greens 2D slices-of-Universe ---then I and many others have had the perception of experiencing that time stopped or extended.
I guess it is like and experience of very long moment between two seconds. So was that due to a contraction of space, or acceleration of chemistry?
r6
All this "time dilation" "length contraction" talk got me to thinking about "contraction"( pulling-in ) of the womb too induce a dilation( expanding-out ) of the cervix to allow baby exit the womb. This is a pulling-in force that leads to a pushing-out force.
Maybe I stated this in reference to gravity in another post. Gravity is a pulling-in( mass-attractive ) force--- see non-observed graviton :--) ---and as a result of gravities pulling-in, there is a resultant pushing-out reaction called dark energy or cosmological constant.
If I recall correctly, the new news out regarding Wienstiens TOEeveything, is that there is not repulsive, cosmological constant ergo no dark energy. He apparently believes that the observed Universe we see is just a flat part of a greater Universe, and this flatness is what cause the appearance of a cosmological constant or dark energy.
So it appears to me, that, just as some believe that gravity is purely a geometrical subcataory of mathematics, I believe that, the cosmological constant is a resultant of spactime contraction, and similar to the situation with the fetus/baby exiting womb to become independent baby.
I'm curious to see how Wienstien handles the constancy of speed-of-radiation and gravity( mass-attraction ) as a force of nature or just mathematical subcategory of geometry.
My feeling is that there exists tubes of nature that feed into larger containment chambers--- ex polyhedral, spherical whatever ---that then have exit tubes/pathways canals etc.....on both the macro, medio, micro and ultra-micro scales of existence.
If mass-attraction did not exist, Universe would not exist. Time/accelearation(?) dilation and space/length contraction?
How do we simplify this for the common human? If we say that speed-of-radiation is like time standing still--- see Brian Greens 2D slices-of-Universe ---then I and many others have had the perception of experiencing that time stopped or extended.
I guess it is like and experience of very long moment between two seconds. So was that due to a contraction of space, or acceleration of chemistry?
r6
This is just an observation of fact but not the answer to my question "WHY?".
"Why this fact is so?"
The question still remains...
Answer to be found out...
So, i think Geodesic-Deviation is not the correct answer for my question...
Markus Hanke
Registered Senior Member
They are equivalent because the geometry of space-time is the same for accelerated observers, and observers inside a gravitational field.
Yes it is. Depending on the initial conditions, the geodesic deviation equation will quantitively describe the geometry of your objects' geodesics. This is precisely what you were looking for. Again, the geodesics are what they are because of the geometry of the underlying space-time.
I believe the simplest solution is the best solution.
My theory for why mass attract mass is based on a single special relativity consideration. Energy, such as photons, travel at the speed of light. Mass cannot travel at the speed of light according to special relativity. There is an equivalency between mass and energy but with this one difference, mass/energy can't move at C, but energy can move at C. Mass/energy and energy have this one difference so they are not 100% equivalent. That needs to be updated if truth is important.
The theory is mass attracts mass, so mass/energy, which cannot go C, can phase change back to the version of energy that goes C.
The way to prove this experimentally is to look at mass undergoing the effect if gravity, to see if the C-energy, increases.
We can start with a cloud of mass close to absolute zero, so energy at C is minimized. We will try to begin with essentially pure mass/energy that can't go C and see if gravity causes C-energy to increase.
What should happen, as gravity acts, motion and pressure will increase. This will enhance the C-energy emissions stemming only from the potential energy within the mass/energy (comes only from the <C phase). Once fusion begins we also get mass burn back to C. One can verify that the amount of C-energy increases as mass attracts. The goal of mass attraction is a return to the C-energy phase.
When mass condenses from energy, it goes from C-energy to a condensed state of energy that can't go C. Gravity is one means to return the <C phase of mass/energy back to the C-energy phase.
I think this is the simplest answer subject to experimental proof. No math tricks are used.
My theory for why mass attract mass is based on a single special relativity consideration. Energy, such as photons, travel at the speed of light. Mass cannot travel at the speed of light according to special relativity. There is an equivalency between mass and energy but with this one difference, mass/energy can't move at C, but energy can move at C. Mass/energy and energy have this one difference so they are not 100% equivalent. That needs to be updated if truth is important.
The theory is mass attracts mass, so mass/energy, which cannot go C, can phase change back to the version of energy that goes C.
The way to prove this experimentally is to look at mass undergoing the effect if gravity, to see if the C-energy, increases.
We can start with a cloud of mass close to absolute zero, so energy at C is minimized. We will try to begin with essentially pure mass/energy that can't go C and see if gravity causes C-energy to increase.
What should happen, as gravity acts, motion and pressure will increase. This will enhance the C-energy emissions stemming only from the potential energy within the mass/energy (comes only from the <C phase). Once fusion begins we also get mass burn back to C. One can verify that the amount of C-energy increases as mass attracts. The goal of mass attraction is a return to the C-energy phase.
When mass condenses from energy, it goes from C-energy to a condensed state of energy that can't go C. Gravity is one means to return the <C phase of mass/energy back to the C-energy phase.
I think this is the simplest answer subject to experimental proof. No math tricks are used.
That is not only observational fact. It is theoretically too. You cannot show Gravity as being repulsive theoretically also. and that is why gravity is always attractive. Understood?
Geodesic-Deviation is just another way of explaining Newton's concept of Gravitation. If you ask the question, "Why geodesic-deviation happens?"; you will get this answer.
Correct.
That is also my question, "why there is no repulsive force between two mass?".
Not very correct. Precession of Mercury is not exactly attractive. Some precession effect is also there alongwith the 'attractive gravity'.
Markus Hanke
Registered Senior Member
Already been answered. To get a geometry which resembles a "repulsion" effect you would need a source with negative energy density, i.e. exotic matter. We don't find this in nature to the best of our knowledge, that is why we observe only attraction, as described by the Einstein field equations.
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