# Why two mass attracts each other?

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

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1. ### hansdaValued Senior Member

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The "time" which you are referring above is "time as indicated by a local clock". This "time" is dependent on clock. This "time" is dependent on gravity as the clock is affected by gravity because mass and energy of a clock can not escape "Gravitational-Field". This "time as indicated by a local clock" can undergo "time dilation".

The "time" which i am referring here is the "real time". This "real time" is independent and uniform for all mass, energy, space and their relative motions. This "real time" moves only in one direction(arrow-of-time) from past to present to future. No clock can hold this "real time". This "real time" is independent of clock or gravity and does not undergo "time dilation".

So, you should understand the difference between the "time as indicated by a local clock" and the "real time".

So, the "time as indicated by a local clock" is not the "real time".

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3. ### Beer w/StrawTranscendental Ignorance!Valued Senior Member

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Metaphysics?

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5. ### hansdaValued Senior Member

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It is still open.

Why there is no possibility of "appear to repel"?

Lorentz-Force is due interaction of Electrical-Field and Magnetic-Field. Lorentz-Force can also move a massive object. Is Lorentz-Force due to "spacetime-distortion(or dimple)?

I think there may be some connection between "Gravity" and "Lorentz-Force".

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7. ### hansdaValued Senior Member

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"Real Time" always keeps us in the "present". "Time Reversal" is not yet proven, not in the particle level also.

8. ### eramSciengineerValued Senior Member

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Farsight does have a few screws loose

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, but I'm pretty sure he's not alone.

In geek speak, Farsight just doesn't have enough processor speed.

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About time he realized his limitations.

@Markus, first Farsight. now hansda.

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hansda's a little senile though. In this thread, he had great difficulty understanding Newton's cradle, Newton's third law and even basic energy transfer.

Last edited: May 14, 2013
9. ### Beer w/StrawTranscendental Ignorance!Valued Senior Member

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That has to be the crappiest strawman -my sentence consisted of one word!

10. ### eramSciengineerValued Senior Member

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He's probably got dementia so god knows what's going on inside his mind.

11. ### Write4UValued Senior Member

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Because gravity is the only force that is effective at great distances.

http://csep10.phys.utk.edu/astr162/lect/cosmology/forces.html

I identified the other three forces as being caused by differences in potential, i.e. polarity.

IMHO, perhaps the Lorentz force is indirectly connected to Gravity in that it deals with momentum and kinetic force of massive objects, each of which has a gravitational field of course. Interestingly, the below quote seems to confirm my statement that the center of gravity is always located at the greatest concentration of combined masses. In the case of a BH this point is a singularity, in the case of galaxies the center of gravity may not lie inside an object at all, but at the center of the system itself.
http://physics.gmu.edu/~pnikolic/PHYS308/lectures/relativity2.pdf

12. ### PhysBangValued Senior Member

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More appropriate would be to say that he's trying to edit a picture with photoshop, but he only has the Windows bitmap editor.

13. ### ash64449Registered Senior Member

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what is 'time' then? Can you explain what 'real time' is? How you define this 'real time'?

14. ### ash64449Registered Senior Member

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wait...
Why two masses attract each other?
Its all in equivalance principle!!

15. ### hansdaValued Senior Member

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How? Can you prove?

"Two mass attract each other." - This is an observable fact. You should be able to explain, "why"?

16. ### hansdaValued Senior Member

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"Time Reversal" is not yet experimentally proved. "Time Reversal Violation" has been experimentally proved."Time Dilation" is also proved with a clock.

So, it can be said that "time as indicated by a clock" dilates but "flow of time" which follows 'arrow of time' does not 'reverse back', 'slow down' or 'dilate'.

This "flow of time" can be considered as the 'real time'.

17. ### ash64449Registered Senior Member

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find it out yourself

18. ### ash64449Registered Senior Member

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you do not understand what you are saying!! Ur words don't make sense because you haven't define what 'time' is.
So what is 'time'? And you are saying there are two types of time:'real' time and proper time and coordinate time. So here are different types of time. But what is 'time'? Got the point? From that definition (your own) of 'time',distinguish 'real' time and other time.

19. ### hansdaValued Senior Member

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"Distance" determines the strength of a "force" but not its direction. "Force" also can be 'repulsive at a distance', as in the case of Electrical charges or magnets.

20. ### hansdaValued Senior Member

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"Time" is the non-spatial interval between two events. "Real Time" is the natural flow of this time. "Real Time" is uniform, independent of gravity and follows 'arrow of time'.

"Time indicated by a clock" is not "Real Time". "Time indicated by a clock" is non-uniform, 'dependent on gravity' and 'undergoes time-dilation'.

For example if a clock can be kept at Black-Hole, this clock will show 'no passage of time' but 'arrow of time' is present there. "Real Time" is present in the Black-Hole but "time as indicated by a clock" is not present in the Black-Hole.

21. ### OnlyMeValued Senior Member

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Hansda, time is an abstract label we use to define the rate that change occurs at. Change does occur even when we are not observing or measuring it, but time requires that "we" make some rate of change comparison, with a predetermined standard rate. In some ways you could say that choosing a standard rate of change is arbitrary. It has changed over the corse of history, as we have discovered more accurate mechanisms, to reference as a standard.

Change is real and is not observer dependent. The rate of change or what we call "time" is observer dependent. It depends on from where we observe events or change and what mechanism we use to define a standard rate. There is no universal time or rate of change, because we are limited to observing and measuring change, the rate of change, or time.., from where and when we are located. We can project how the rate of change would be affected by changes in location and velocity, but even then we are only labeling the rate of change for another unique frame of reference, not any universal frame.

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

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I couldn't agree more. Time simply passes. The measurement of time is variable based on the energy density of the environment.

As Markus says elsewhere, "Space-time Geometry = Energy Content"

"And this is exactly what GR is all about; gravity is not described in terms of forces, but as a geometric property of space-time itself. Space-time curvature and energy content are one and the same thing; we can interpret this as energy "curving" space-time, or equivalently as curvature manifesting itself as energy, e.g. mass."

23. ### OnlyMeValued Senior Member

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GR does not describe "gravity".., it describes the "affects" of gravity.