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What Is Gravity?

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Why do objects attract each other? Where does the energy come from to move the objects together?

I don't think anyone knows the answer to this. Hence CERN and Hadron colliders and stuff.

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F = GMm/r^2

F force - Newtons

G gravitational constant- 6.672 × 10−11 m3/kg/s2

M mass of object 1 - kg

m mass of object 2 - kg

r radius/distance between M & m - meters

Nobody knows what it is though.

Like energy.

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Guest X-QUORK

I don't think anyone knows the answer to this. Hence CERN and Hadron colliders and stuff.

Correct, in a nutshell, we don't know.

What we do know is that objects bend the space/time surrounding them, one analogy used is a cannon ball sitting on a suspended sheet, with the sheet being a 2D section of space/time being warped by the "weight" of the cannon ball. Imagine then a ball-bearing being rolled into the sheet, it will clearly roll into the centre until it rests against the cannon ball, much as an asteroid would be if passed too close to Earth and became "pulled" in by the gravity of Earth, or the warping of space/time.

I don't see gravity as a force in itself, more a way of describing warps in space/time.

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Guest theboltonfury

Why do objects attract each other? Where does the energy come from to move the objects together?

Don't know. Give me one on sport.

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A thing with mass moves in time slower than a thing with lesser mass.

the universe always tries to stay level and remain balanced, so the one moving faster in time is dragged back by the slower one.

simples

explains why the Universe looks like it started with a big bang.

All the above copywrite Bloo Loo and all rights reserved by the poster.

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Correct, in a nutshell, we don't know.

What we do know is that objects bend the space/time surrounding them, one analogy used is a cannon ball sitting on a suspended sheet, with the sheet being a 2D section of space/time being warped by the "weight" of the cannon ball. Imagine then a ball-bearing being rolled into the sheet, it will clearly roll into the centre until it rests against the cannon ball, much as an asteroid would be if passed too close to Earth and became "pulled" in by the gravity of Earth, or the warping of space/time.

I don't see gravity as a force in itself, more a way of describing warps in space/time.

why would it roll down the sheet? If you did this analogy in space, the ball bearing would just sit there. What would pull the ball bearing to the centre?

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Guest X-QUORK

One surreal aspect of gravity - it is like a web of information. When I blink an eye-lash, there is a very slight tug on everything else in the Universe, even on the rubber duck in the bath-tub of a middle aged Lizard-man in the Andromeda Nebula. Strange to think - if you wiggle your finger around, every atom in the universe is moved very slightly, everything is slightly different afterwards.

The big question you've posed could be childishly rephrased by me as, how do they (all the little atoms and particles) all "know" about every tiny move of everything else, everywhere?

Quantum entanglement will blow your mind then Durch. Take two particles that are billions of light years apart, change the state of one and the other will also change because they're entangled. The distance between them matters not a jot.

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Guest X-QUORK

why would it roll down the sheet? If you did this analogy in space, the ball bearing would just sit there. What would pull the ball bearing to the centre?

Imagine an asteroid whizzing along on a straight trajectory past the Earth. As it nears the dip in space/time caused by the mass of the Earth, it "falls" into it, much as the ball bearing would on the sheet example.

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One surreal aspect of gravity - it is like a web of information. When I blink an eye-lash, there is a very slight tug on everything else in the Universe, even on the rubber duck in the bath-tub of a middle aged Lizard-man in the Andromeda Nebula. Strange to think - if you wiggle your finger around, every atom in the universe is moved very slightly, everything is slightly different afterwards.

The big question you've posed could be childishly rephrased by me as, how do they (all the little atoms and particles) all "know" about every tiny move of everything else, everywhere?

thats odd...I felt that.

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the one moving faster in time is dragged back by the slower one.

But the bigger object doesn't just move the smaller object, they move each other.

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Quantum entanglement will blow your mind then Durch. Take two particles that are billions of light years apart, change the state of one and the other will also change because they're entangled. The distance between them matters not a jot.

Yes, and it's been proven that they do not have any "hidden variables" that decide this entanglement, they do literally communicate instantenously via some form of universal consciousness.

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But the bigger object doesn't just move the smaller object, they move each other.

relatively speaking

If im on the moon, the Earth is drawing me nearer.

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Some people say that gravity pulls things together ever faster but this cannot be true. Gravity makes things heavy and the opposite of heavy is light. Since the speed of light is the fastest there is, it follows that the speed of heavy is the slowest, which is motionless. Thus gravity makes things stop.

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Some people say that gravity pulls things together ever faster but this cannot be true. Gravity makes things heavy and the opposite of heavy is light. Since the speed of light is the fastest there is, it follows that the speed of heavy is the slowest, which is motionless. Thus gravity makes things stop.

No.

Newton's second law states:

A body experiencing a force F experiences an acceleration related to F by F = ma, where m is the mass of the body. Alternatively, force is equal to the time derivative of momentum.

One cannot escape Newton's laws, unless you are talking quantum mechanics.

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The big question you've posed could be childishly rephrased by me as, how do they (all the little atoms and particles) all "know" about every tiny move of everything else, everywhere?

I don't think it helps to ask things like: how does a river know how to get to the sea, or how does a vacuum flask know to keep hot drinks hot and cold drinks cold.

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Wikipedia is your friend:

Gravy is a sauce made often from the juices that run naturally from meat or vegetables during cooking. The gravy may be further coloured and flavoured with gravy salt (a simple mix of salt and caramel food colouring) or gravy browning (gravy salt dissolved in water) or ready-made cubes and powders can be used as a substitute for natural meat or vegetable extracts. Canned gravies are also available. Gravy is commonly served with roasts, meatloaf, rice, and mashed potatoes.

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More seriously, the OP's question is unanswerable with our present knowledge.

The universe is essentially made of energy/matter, and force acts upon it. They appear to be the fundamental components of the universe.

In the early nanoseconds of the universe, force seperated into the four forces we know today; electromagnetic, weak nuclear, strong nuclear, and gravity. Einstein described gravity as a distortion of space/time.

Wondering what is applying the force, or why, is probably fruitless. From our viewpoint within the universe, the forces are simply there. Whether we will ever be able to see beyond our universe to see why matter or forces exist seems unlikely to me.

On the other hand, greater minds than mine have thrown light on the 'unanswerable' by daring to ask such questions.

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It's a funny old thing, but the Victorians reckoned they knew pretty much everything science had to offer. A hundred years down the line we're only just beginning to find out what we don't know, and rathan than science explaining away religion, I feel it's almost getting to a stage where we have to 'blame' a God, because we really have no idea.

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It's a funny old thing, but the Victorians reckoned they knew pretty much everything science had to offer. A hundred years down the line we're only just beginning to find out what we don't know, and rathan than science explaining away religion, I feel it's almost getting to a stage where we have to 'blame' a God, because we really have no idea.

If you wanted to design a universe where a God could do stuff without being noticed, this universe is pretty damn close.

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  • 277 Brexit, House prices and Summer 2020

    1. 1. Including the effects Brexit, where do you think average UK house prices will be relative to now in June 2020?


      • down 5% +
      • down 2.5%
      • Even
      • up 2.5%
      • up 5%



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