A general Question about Gravity and Quantum Physics

[i_am_a_newbie]

Hi,

My name is Paul and I have a question to pose that I feel you chaps may be able to help me with. Last night I was letting my mind wonder and I was thinking about Gravity and how I think it is an effect of a cumulated Quantum force. Remember it was just my mind wondering also I am not a scientist nor have I been educated in Science past high school so if I am totally wrong please let me know :)

I was postulating to myself what it would be like if I could make a planet. If time was no object nor money, nor space flight. What if I could make many trips to a stable point in space, taking with me a lot of pebbles. For arguments sake each weighs 1kg, now I've put some numbers into a computer and calculated how many I need and how many trips I need to take to complete my planet. Let’s also say my planet will be Earth sized, and generally have the same density and gravity of Earth. Now how many pebbles I need and how I get them is irrespective in this hypothetical argument. Let’s just say I create this "Pebble Planet" even though it would take too long and cost too much, let’s put that aside and talk about some science on this new creation lol.

Ok I have a few questions for people with a far greater understanding of Gravity than myself.

a) On my pebble planet aside from having no atmosphere, can I roam around just like on earth, would having the same mass and density as Earth be enough to hold my pebble planet in place?

This made me wonder, I said to myself "of course it would have the same Gravity"..I then wondered about Gravity itself, could it be a "field effect" for instance... All my pebbles stay to together but how do they know how to do so. My next question to myself was this.

b) Is there a Quantum interaction by atoms close together i.e. on a larger scale do all my pebbles on my pebble planet interact with each other in a seemingly invisible way to stay together.

This led me to a further question.

c) For this effect for to be stronger, this Quantum effect would somehow have to accumulate when in closer proximity to other matter.

and

d) Could Quantum Entanglement be used to explain this kind of "communication" at a sub atomic level?

The final question I pondered was about spin and was in relation to b and c.

d) If this effect can accumulate, so matter itself can accumulate through the force of gravity and a sub-atomic particle was responsible for this force. If this particle could interact with other particles to create Gravity what if this sub atomic particle has spin, would the spin also be a cumulative effect?

Sorry if this is long winded or if it's just plain rubbish, I'm just hoping someone can set me straight or if our knowledge on Gravity as a race is insufficient to explain the observations of what we see.

 

[K^2]

All of the questions after a) don't make any sense. Don't use the word "quantum" to describe anything you don't understand. While the fact that you don't understand anything quantum seems to be true, it doesn't work the other way around.

Yes, if you make your pebble planet massive enough, you'd be able to walk on it. In fact, you might even end up with a bit of an atmosphere as a side effect. Depends on what sort of rocks you keep brining with yourself. The actual surface gravity will depend on total mass and average density, so the planet being just as big as Earth doesn't necessarily mean it will have the same gravity. Still, you should be able to find the right number of pebbles to get the surface gravity to be exactly the same.

The pebbles you build the planet out of don't "know" anything about other pebbles. Each one generates its own gravitational field. The total field is a simple sum of fields from individual pebbles. (Strictly speaking, it's not, because of General Relativity, but correction is minor even for a planet.) The net force will be pulling all of the pebbles towards the center, because that's always the direction where there are more pebbles, meaning gravity would pull that way. And if you have gravity pulling towards the center, the configuration that would make all of the pebbles as close to the center as possible is a sphere.

 

[i_am_a_newbie]

Hi K^2,

Thanks for your response, true enough I don't understand about 99% of Quantum Physics so I do apologise for applying it outside of a context I understand, alas my mind was only wondering :) Thank you for your answer if b/c/d don't make sense then I don't need to spend any more time wondering about it. I think the reason I postulated to the question to myself was because I couldn't understand what allows each pebble to have it's own graviational field (although minor) and allows the pebbles to also act like one giant planet sized pebble. One more question I had was if I dug down from the surface of the pebble planet to the centre would the force of gravity diminish as I got closer and closer to the centre of the mass of pebbles?

 

[K^2]

Yes, it would decrease. There might be a slight increase early on due to variations in density. Odds are, your pebbles will be crushed and fused together at the depth, so density is going to be higher there.

 

[i_am_a_newbie]

Hi,

Thanks K^2 for your speedy replies and for setting me straight, I think my question shows I need to spend more of my time researching the subject rather than trying to explain everything with a fantasy quantum world I have created!

Many Thanks