How Dense Can You Get? Science Behind Creating a Gravity Bomb

  • Thread starter JanKo
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In summary: So come on great minds, help me out here and offer me a your opinion/new idea/anything!I mean, sure, I could just make stuff up to explain this, but I would actually like a little science behind it.I don't know much about gravity, but why would it destabilize or explode? To the best of my knowledge black holes don't regularly explode, and wouldn't this just be a mini black hole? I'd think it'd suck everything in around it and just keep growing denser and more massive until it ran out of matter in its area of the universe to suck in and would eventually evaporate or float off into a different solar system to suck in other stars
  • #1
JanKo
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Hello everybody!

I have a question that's been bugging me for some time now, considering density and mass and gravity and so on.

I'm writing this short story for a local magazine (Yes, it's Sci-fi :approve:) and I came upon the idea that you could make what I call a "Gravity bomb."

A weapon that would use gravity to destroy... well, stuff.

And here is how I pictured it.
It would look like a typical rocket-type missile, but instead of being filled with gunpowder and exploding on impact it would - after some kind of chemical reaction within or something - I don't know :confused: - acquire such a big mass that it would have such a powerful gravity field that it would suck in everything in it's surrounding, ripping trees out of the ground, tearing down buildings, lifting cars and people in the air and towards itself.

And after some time, let's say 30 sec, it would destabilise and explode, blowing away everything that it had pulled toward itself and thus causing more damage.
(I'm evil, I know)

I thought of a dying star, but kinda in reverse (and a lot lot smaller :smile:)... First having this small object or something with a lot of density that would then destabilise and explode.


I'm currently going for this:
The missile would have something inside like materials that would, upon impact with an object/ground, react with each other and have a far greater mass than they had before - and I'm talking HUGE mass - thus creating this BIG gravitational field.
The new material would be highly unstable and would destabilise fast, whether in contact with the air or in another way, causing it to explode.


Now, the big question o:)!

Would anything like this be even remotely possible?
Could you, if you had the technology, make two or more (hypothetical) materials react in such a way, that the resulting material's structure would arrange itself in a way that there would be almost no space between it's particles or atoms, resulting in high density and therefore a very strong gravitational pull.

And could it be possible that anything as small as a soccer ball would have all these properties?
Would you do it using nanotechnology?
Just a chemical reaction?
What do you think would be the (easiest) way to accomplish this?
Or am I going about this completely the wrong way and should just go and lock myself in the closet for talking complete nonsense?


So come on great minds, help me out here and offer me a your opinion/new idea/anything!

I mean, sure, I could just make stuff up to explain this, but I would actually like a little science behind it.
 
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  • #2
I don't know much about gravity, but why would it destabilize or explode? To the best of my knowledge black holes don't regularly explode, and wouldn't this just be a mini black hole? I'd think it'd suck everything in around it and just keep growing denser and more massive until it ran out of matter in its area of the universe to suck in and would eventually evaporate or float off into a different solar system to suck in other stars and planets.
 
  • #3
It would look like a typical rocket-type missile, but instead of being filled with gunpowder and exploding on impact it would - after some kind of chemical reaction within or something - I don't know - acquire such a big mass that it would have such a powerful gravity field that it would suck in everything in it's surrounding, ripping trees out of the ground, tearing down buildings, lifting cars and people in the air and towards itself.
Where would this mass come from? There can't be any more mass than it started with!
 
  • #4
Calm down, man :smile:
You see, that's why I need you folks to point out such things :smile:

Ok, so you definitely can't get more mass than you put in, right?
Can we somehow get around this problem?
How would I explain a sudden gravity field that wasn't there before, do you know what I mean?
 
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  • #5
NerfMonkey said:
I don't know much about gravity, but why would it destabilize or explode? To the best of my knowledge black holes don't regularly explode, and wouldn't this just be a mini black hole? I'd think it'd suck everything in around it and just keep growing denser and more massive until it ran out of matter in its area of the universe to suck in and would eventually evaporate or float off into a different solar system to suck in other stars and planets.

It would. In fact, anything within its event horizon (which is basically the point of no return - once within it, nothing can escape) would be dragged into it, adding more mass and more density to the black hole. Eventually, the planet itself would join it (the "p" in the equation below is a rho, the symbol for density, not a lower case p):

p = m/v

If more matter joins the blsck hole, then its volume must increase so density wouldn't increase, right? No, because the black hole still remains the size of a particle - the density is so high that gravity is so strong that it even crushes the atoms (density is mass per unit volume).
 
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  • #6
So there is no way in hell, that you could make a gravity field so strong but not get a black hole?
 
  • #7
JanKo said:
So there is no way in hell, that you could make a gravity field so strong but not get a black hole?

I'm nowhere experienced enough to give you a definite answer, but I guess so. There must be some kind of minimum density that black holes must have for them to be...black holes.
 
  • #8
Damn it...
Ok, putting mass and density aside...
Could you produce such a gravity field in another way?
 
  • #9
yeah I don't know much about black holes to be of help much either but..

at what point do stars implode under their own weight to become black holes? maybe if you knew the answer to that it might help...
 
  • #10
JanKo said:
So there is no way in hell, that you could make a gravity field so strong but not get a black hole?
Sure you could. There's lots of things between regular matter and black holes. The most obvious is neutronium.

The trouble is, gravity is directly equivalent to the amount of mass - and that alone. Where does the mass come from?
 
  • #11
Yes, I've heard about the "Schwarzschild radius".
The Earth has a schwarzschild radius of 9mm, meaning that if you would compress all of the world's mass into a "ball" which had a radius of less than 9mm it would turn into a black hole.

So everything has the potential of being a black hole, you just have to compress it to a right size.

Neutronium... A matter composed primarily of neutrons.
That sound's good.
But you're right, It still doesn't solve the problem of the magically appearing mass :rolleyes:
 
  • #12
Relativity predicts gravitomagnetism. Though it predicts something very small, look up the work by the ESA on it, it's far larger than thought under certain circumstances:

http://www.esa.int/SPECIALS/GSP/SEM0L6OVGJE_0.html

Only a matter of time, methinks.
 
  • #13
A gravity bomb? That would be awesome. As to its construction, that is the poser.
 
  • #14
Of course, if the payload of your missile contained one end of a wormhole... you'd have some interesting choices about where to put the other end.
 
  • #15
So, dst, let me ask you if I got this right.
I probably didn't, but here I go.

So, what this device is doing is using gravitomagnetism by spinning a superconductor very very fast and so generating a gravitational field?

And what's the difference between gravitoELECTRIC and gravitoMAGNETIC field?
(It's on the "sketch" of the device in the text)
 
  • #16
JanKo said:
So, dst, let me ask you if I got this right.
I probably didn't, but here I go.

So, what this device is doing is using gravitomagnetism by spinning a superconductor very very fast and so generating a gravitational field?

And what's the difference between gravitoELECTRIC and gravitoMAGNETIC field?
(It's on the "sketch" of the device in the text)

It's a fair bit stranger than that. Look up things like "Lense-Thirring Effect" or "Frame dragging". Something rotating fast or massively will simply "drag" space & time around it. I don't know whether you could call that a "magnetic" field in the classical sense, because it's quite different. The effect is tiny, but with a superconductor it appears to be much larger (still ludicrously small though).

As for the idea of "gravitoelectric" and "gravitomagnetic" fields, that would be an analogy to Maxwell's equations and hence the idea of one inducing the other.

Here's more on that: http://arxiv.org/ftp/gr-qc/papers/0107/0107012.pdf
 
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  • #17
Here would be the main problem I would see: where does the mass come from? If it comes from the surroundings on impact, then the damage would be much greater from the act of gaining mass then from the act of a gravitational pull.

In addition, if you are aiming to damage the area through a black hole, the act of compressing the object into a black hole would probably need the use of a high energy explosion around the mass, and would likely detroy the entire Earth (and more) before making the mass into a black hole.
 
  • #18
JanKo said:
So, dst, let me ask you if I got this right.
I probably didn't, but here I go.

So, what this device is doing is using gravitomagnetism by spinning a superconductor very very fast and so generating a gravitational field?

And what's the difference between gravitoELECTRIC and gravitoMAGNETIC field?
(It's on the "sketch" of the device in the text)

Another problem with this is the act of keeping the superconductor spinning really fast. Although superconductors are void of friction, air resistance is a problem. For one, if this indeed could cause damage, you would have to keep it from spinning fast until impact, at which time it would start spinning (that is huge amounts of angular acceleration. Just huge). Aside from that, a vacuum would need to be maintained constantly in order to combat air resistance, and due to the speed that the superconductor would be spinning, it would have to be an absolutely perfect PERFECT vacuum, which would require a huge missile as well as a clean environment which...just cannot survive any use as a bomb.
 
  • #19
Ok, no black holes, that's clear now. :cool:
But let's, just for the fun of it, say that you would be able to produce these perfect conditions. A completely air-tight chamber with perfect PERFECT vacuum.
And let's say, that you could have two (or maybe even more) of these chambers each spinning in the other direction.

Do you know what I mean?

You would have a chamber that was spinning in one way with the superconductor inside (also spinning), and another air-tight chamber around that one which would be turning in the opposite direction.

Would this increase the speed of the conductor and dragging of space & time even more, or would they just cancel each other out?

(By the way, thanks a lot guys. This is really helping me understand these things a lot lot better than I had before.
So thanks for the effort :blushing:)
 
  • #20
You might break someone's nail with those 0.000000000x Newtons of force it outputs.
 
  • #21
JanKo said:
Ok, no black holes, that's clear now. :cool:
But let's, just for the fun of it, say that you would be able to produce these perfect conditions. A completely air-tight chamber with perfect PERFECT vacuum.
And let's say, that you could have two (or maybe even more) of these chambers each spinning in the other direction.

Do you know what I mean?

You would have a chamber that was spinning in one way with the superconductor inside (also spinning), and another air-tight chamber around that one which would be turning in the opposite direction.

Would this increase the speed of the conductor and dragging of space & time even more, or would they just cancel each other out?

Of course, at that speed, that could be the damage :biggrin:.

Of course, at that speed, that could be the damage :biggrin:.

(By the way, thanks a lot guys. This is really helping me understand these things a lot lot better than I had before.
So thanks for the effort :blushing:)

Just to be thorough, the force of such a speed would cause any superconducting material (or any earthly material for that matter) to break apart.
 
  • #22
There is in theory (though neutron-degenerate matter is technically also still theory) that the core of some neutron stars is composed of strange matter which is matter composed of free up, down, strange quarks & gluons. The difference between strange matter and quark matter (up, down quarks & gluons) is that strange matter is actually considered to be stable (as apposed to an up, down quark & gluon dense plasma which would remain high energy; and electron and neutron degenerate matter which wholly relies on gravity for their composition). Neutron degenerate matter can have a density of up to about 2 billion tonnes per cm^3 while strange matter can have a density anywhere between 2 and 4 billion tonnes per cm^3; neutron stars having a radius of ~12 km, hybrid (quark & neutrons) ~9 km, quark/strange stars ~6 km.

Steve
 
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1. How does density affect the power of a gravity bomb?

The denser an object is, the more mass it has, and the stronger its gravitational pull. In a gravity bomb, this increased mass and gravitational pull can lead to a more powerful explosion.

2. What materials are typically used to increase the density of a gravity bomb?

Common materials used to increase density in a gravity bomb include lead, uranium, plutonium, and other heavy metals. These materials have a high atomic weight, making them dense and capable of creating a strong gravitational pull.

3. Can the density of a gravity bomb be increased indefinitely?

No, there are limits to how dense a gravity bomb can get. Eventually, the materials used to increase the density will reach their maximum capacity and will not be able to compress any further. Additionally, the stronger the gravitational pull, the more likely it is for the bomb to collapse in on itself.

4. How is the density of a gravity bomb controlled?

The density of a gravity bomb is controlled by carefully selecting and arranging the materials inside the bomb. This can involve using layers of different materials with varying densities or strategically placing materials in specific locations to maximize their gravitational pull.

5. Are there any ethical concerns with creating a gravity bomb with extreme density?

Yes, the creation and use of gravity bombs have significant ethical implications due to the devastating destruction they can cause. Additionally, the materials used to increase density, such as nuclear materials, can have long-lasting and harmful effects on the environment and human health.

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