# Why two mass attracts each other?

Discussion in 'Physics & Math' started by hansda, Mar 19, 2013.

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1. ### quantum_waveContemplating the "as yet" unknownValued Senior Member

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While that is completely true, I highly suspect that Markus would accept that statement too. Though he may be comfortable with the concept of gravity being due to the geometry of space-time, he is also acknowledging in that quote that it has the same effect as the energy density of space; he referred to them as having equivalence.

3. ### Write4UValued Senior Member

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Gravity has no "direction" of influence, it is an expression of the 3dimensional nature of space. It causes 3d spacetime to curve toward the massive object. Thus if gravity has a direction it is always toward the massive object and accompanies (surrounds) the object wherever it wanders.

This effect can be clearly seem when a meteor passes a planet , oddly the tail (smallest particles) of the meteor always points toward the planet.

Gravity is not an independent actor or force, it is a distortion of spacetime geometry, caused by a massive object. Without the object, no gravity. Similar to the concept of "spacetime", being a single geometric condition or wholeness where space and time are wedded by dynamic change. Spacetime itself is not a force, nor is a spacetime distortion a force. The causal force in all of this is the mass of an object in motion and has momentum and is causal to a gravitational "wavelike action in spacetime".

5. ### ash64449Registered Senior Member

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events?! Yeah.. You are reaching somewhere!!
But you know time can be spacial intervel. So your 'real time' is not spatial interval? But our time can also be non-spatial interval!!

Your definition of 'time' is wrong and you aren't able to define what 'time' is.

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8. ### ash64449Registered Senior Member

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what i wanted to say is that there is no 'real time'. Time is what is needed for us to describe motion and it is observer depentant. We cannot define what 'time' is until we define a specific object.

And as a result,we can only define 'time' with the help of clocks pointer and events that are simultaneous to it..

9. ### quantum_waveContemplating the "as yet" unknownValued Senior Member

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Oh, I see where you are coming from. But I would change that slightly and then agree, lol. I would say we can be comfortable with saying time simply passes, and when we apply that concept to specific motion, the measurement of time comes into play. Then the clocks and events allow measurement of the amount of time that passes in that particular energy density environment.

10. ### Write4UValued Senior Member

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I think I understand where both of you are coming from. But I would change that slightly and then agree....

IMO, time does not pass unless it is required and created during the event. Time has no existence in and of itself. Time does not exist in the past, the past no longer exists and no time is required for the past. So it is for the future. There is no time yet in the future as events to happen in the future have not yet happened and required time for the event to "complete". As time inexorably becomes entwined with the continuing existence of space, so time becomes entwined with every physical or geometric change of anything.
Time comes into existence only when another measurable action takes place from Planck to Super-novae. Each event needs it's own good time and that time is called that event's world line, the chronology of a continuing expression in reality.

11. ### ash64449Registered Senior Member

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And what is wrong in my statement?

12. ### quantum_waveContemplating the "as yet" unknownValued Senior Member

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And I think you are saying that if we were to read and learn GR, we would know the truth.

I agree with part of that though, time does not exist in the past or the future, it is always now as far as time is concerned, and time does not have any existence in and of itself.

And to be practical and not necessarily being contrary to GR, you are right about time and motion being inextricable entwined, but GR calls for the curvature of spacetime by the presence of matter and energy but does not acknowledge how that curves spacetime.

In the unlikely event that my interpretation of Marcus' comment is accurate, then the varying energy density in space, and particularly as you get closer to massive objects, causes a change in the rate that clocks measure time, not a change in the rate that time passes.

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14. ### Write4UValued Senior Member

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True, and hard as I try it is really difficult to visualize. The closest I can come to an analogy is that of the term 'displacement' of a submarine, the dimple in the water occupied by the submarine. Oddly, the displacement also governs the maximum speed a submarine can attain.

I need instruction on this for sure. From my standpoint, time is created during an event and there is no real passage of time, other than as accompanying the passage of events which take (create) time and create the chronological worldline of every change occurring in the entire spacetime universe, which is the record of the instants of time each event occurred at every spacetime coordinate; as best we can tell and sometimes by assigning different spacetime (time/distance) values, such as 'lightyear' or 'entanglement'.

IMO, somewhere in this vague world I believe that time is very much connected to quantum, which by its very nature has a built in time requirement to function. OTOH, the very potential that allows an event to happen, also imposes limits on how much time an event can take. A quantum event will take only enough time to create a quantum event. A muon's worldline as a muon is very, very short and then it disappears and no longer requires or creates time for its existence (as a muon).

And I see here an important consideration. When we say spacetime is warped we really mean the geometric shape of space is warped (folded) and this space distortion also creates as a RESULT folded time and along with variations in distances in the spacetime fabric accompanying variations in the passage of time. Stand close to a pyramid and time will slow down by it's massive gravitational spacetime distortions.

Sometimes a warp may compress space and things may seem to happen faster and sometimes space is stretched and things may seem to happen slower. Certain "equal" distances between coordinates are no longer equidistant from each other and anomalies begin to form in the worldliness of objects in such a spacetime curvature. As observable in "lensing" maybe?

Is it True?
That for any measurable change to be able to occur, a certain amount of time is required and time is always a result of an actual measurable change?
If yes, why do we assume time to exist where there is no change and I do not mean some sort of half life, but when all particles stop moving, when quantum itself stops, what would be the NEED for time?

This is why I maintain that time did not exist before the BB and was created during the 'inflationary epoch', the First mega quantum event where everything happened in the same space at the same time. A momentary chaos, which almost immediately began to order itself in accordance with this Universe's Potential. I just love Bohm's expression, the meta physical 'Implicate' of that which is to become 'Explicate' in reality, along with the amount of actual or relative time it may require.

15. ### Write4UValued Senior Member

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I would not presume. However, if you see that much depth in my musings, I thank you, Sir.

My views are wholly intuitive, but based on reliable bits and pieces of what I believe to be pertinent information. And I would never argue against scientific consensus. I know my limitations.

16. ### ash64449Registered Senior Member

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I totally agree with this...

17. ### bolonnyRegistered Member

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ok a ?....mass attracts mass fact....the further into the earth you dig the lighter one becomes fact....so at a certain point there would be more dirt toward the surface of the earth then toward the center so why is the center of the earth not hollow<im not one of those crazy conspiricy theory people> i just think that the way gravity works that it impossible for it to be solid...think about it your in the very center you would have mass attracting you from all sides therefore being wieghtless..so at what point traveling into the center would there be an equal amount of mass above you and below you???.......i was thinking hard about this one evening then looked it up and found an interesting picture of a hollow earth and all the crazies out there but if the earth were to be hollow it could explain alot about all our planets

18. ### hansdaValued Senior Member

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I also implied that, "Real Time" simply passes as a 'natural flow of time'.

This is "Time as indicated by a clock" and is 'gravity dependent'.

"Energy Content" of what? - "Energy Content of space? "Energy Content" of time? Dark energy of space? Field energy? or some other form of "energy content"?

Energy curves spacetime or mass curves spacetime?

Though mass has rest-energy but "inertia" is exclusive property of mass and not energy. So, mass and energy can not be same.

19. ### hansdaValued Senior Member

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Gravity is a vector quantity. So, it should have a direction. "3d" can not be spacetime. Either '3d space' or '4d spacetime'.

May be this is due to high speed of meteor.

Is there any "qualitative difference" between "Gravitational Force" and "Lorentz Force"?

20. ### ash64449Registered Senior Member

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look clocks don't simply dialate. It is due to the true nature of space-time itself.

21. ### eramSciengineerValued Senior Member

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I've heard this before. "The clock does not march, but time marches on", right?

Einstein asked this question, "Does the Inertia of a Body Depend upon its Energy-Content?"

22. ### hansdaValued Senior Member

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I think GR is better than Newtonian concept in the sense GR is able to predict more. Strength of GR lies in its mathematics. But this "time" concept of GR, i find a bit confusing.

23. ### ash64449Registered Senior Member

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my answer is yeah. And as the speed increases,energy-content increases. So as to accelerate to even higeher velocity,we would need to put lots of amounts of energy as inertia of object increases..