Thread: May 2008 (LHC) Particle Accelerator - Miracle or Catastrophe?

Originally Posted by khh

It doesn't have a theoretical capacity to implode the earth, that makes no sense. It's just an example of doom-sayers.

However, it is a very complicated and super-advanced piece of machinery, and so it takes some time to get it functioning properly.

How much do you know about it? The "doom-sayers" are legitimate scientists. The idea that this is not something to worry about is based on the fact that any black hole created by the LHC will be small enough that they will evaporate through hawking radiation before it is able to absorb any other matter. Hawking radiation has never been observed and so if that theory is incorrect, then such a black hole could indeed gain mass and become self sustainable. If this were to happen, it would fall through the earth, collecting matter on the way, get trapped in the earth's gravitational field and seesaw back and forth through the planet until the entire thing is consumed, thus imploding the earth.

The possibility of this is extremely small, and yet not zero. This is just one reason why we tread lightly.

Didn't all this LHC danger hype originate with some random highschool science teacher?

Originally Posted by Xaqaria

How much do you know about it? The "doom-sayers" are legitimate scientists. The idea that this is not something to worry about is based on the fact that any black hole created by the LHC will be small enough that they will evaporate through hawking radiation before it is able to absorb any other matter. Hawking radiation has never been observed and so if that theory is incorrect, then such a black hole could indeed gain mass and become self sustainable. If this were to happen, it would fall through the earth, collecting matter on the way, get trapped in the earth's gravitational field and seesaw back and forth through the planet until the entire thing is consumed, thus imploding the earth.

The possibility of this is extremely small, and yet not zero. This is just one reason why we tread lightly.

Just like hawking radiation, the idea that there's a chance of micro black holes forming in the LHC is too a theoretical prediction.

I'm no physicist, but I have a hard time believing that a collision alone (like in the LHC) can create a micro black hole. Black holes require enough mass to implode themselves through gravity, and the mass of a couple of subatomic particles is, well...

The Earth gets bombarded by near-light speed cosmic rays all the time and we're all still alive.

Originally Posted by Spartiate

I'm no physicist, but I have a hard time believing that a collision alone (like in the LHC) can create a micro black hole. Black holes require enough mass to implode themselves through gravity, and the mass of a couple of subatomic particles is, well...

The black holes being talked about with this thing are extremely extremely tiny.

The Earth gets bombarded by near-light speed cosmic rays all the time and we're all still alive.

That's cause it's not particles.

Originally Posted by slash112

The black holes being talked about with this thing are extremely extremely tiny.

Say two protons collide and somehow form a black hole, the resulting black hole would have a mass of at most two protons. Black holes aren't vacuum cleaners that suck everything around them, they attract stuff through gravity. I don't think a singularity billions of times less massive than a spec of dust (if one could even sustain itself) would pose a threat to the planet. The power of stellar black holes comes from the fact that they are many times more massive than our sun yet are only a few kilometers across.

That's cause it's not particles.

Yes they are.

Cosmic rays are energetic particles originating from outer space that impinge on Earth's atmosphere. Almost 90% of all the incoming cosmic ray particles are simple protons, with nearly 10% being helium nuclei (alpha particles), and slightly under 1% are heavier elements, electrons (beta particles), or gamma ray photons.[1] The term ray is a misnomer, as cosmic particles arrive individually, not in the form of a ray or beam of particles. However, when they were first discovered, cosmic rays were thought to be rays. When their particle nature needs to be emphasized, "cosmic ray particle" is written.

Originally Posted by Spartiate

Say two protons collide and somehow form a black hole, the resulting black hole would have a mass of at most two protons.

Exactly. While the they might be so close that their gravity prevents them from being separated, they won't have enough mass to exert that kind of power on any other particles, and therefore no new mass will join them.

Originally Posted by Spartiate

The power of stellar black holes comes from the fact that they are many times more massive than our sun yet are only a few kilometers across.

The singularity itself is theoretically only a single point, even if the event horizon is bigger.

Exactly. While the they might be so close that their gravity prevents them from being separated, they won't have enough mass to exert that kind of power on any other particles, and therefore no new mass will join them.

I don't understand this. Doesn't the strong force increase faster than the gravitational force with decreasing distance anyway? Talking about two neutrons here.

And with two protons, the electrostatic repulsion force increases at the same rate as gravity, but it's always greater than it by a very large ratio.

Originally Posted by Spartiate

Say two protons collide and somehow form a black hole, the resulting black hole would have a mass of at most two protons. Black holes aren't vacuum cleaners that suck everything around them, they attract stuff through gravity. I don't think a singularity billions of times less massive than a spec of dust (if one could even sustain itself) would pose a threat to the planet. The power of stellar black holes comes from the fact that they are many times more massive than our sun yet are only a few kilometers across.

Yea, I never said that they were going to get bigger.

I was just saying that this was wrong:

I have a hard time believing that a collision alone (like in the LHC) can create a micro black hole.

And as for this:

Cosmic rays are energetic particles originating from outer space that impinge on Earth's atmosphere. Almost 90% of all the incoming cosmic ray particles are simple protons, with nearly 10% being helium nuclei (alpha particles), and slightly under 1% are heavier elements, electrons (beta particles), or gamma ray photons.[1] The term ray is a misnomer, as cosmic particles arrive individually, not in the form of a ray or beam of particles. However, when they were first discovered, cosmic rays were thought to be rays. When their particle nature needs to be emphasized, "cosmic ray particle" is written

...Touché

I forgot about the alpha and beta radiation.
But protons aren't particles. (i.e. the 90% that hits the earth)

Originally Posted by Spartiate

I'm no physicist, but I have a hard time believing that a collision alone (like in the LHC) can create a micro black hole. Black holes require enough mass to implode themselves through gravity, and the mass of a couple of subatomic particles is, well...

The Earth gets bombarded by near-light speed cosmic rays all the time and we're all still alive.

As far as the fabric of space time is concerned, mass and acceleration are the same thing.

The cosmic ray argument is refuted by the simple fact that if cosmic rays were to create a miniature black hole in our atmosphere (and it didn't immediately decay), its momentum would carry it through the earth and out the other side, off into the void of space. A black hole created by a particle accelerator would start out relatively stationary and so would get trapped in earth's gravitational field.

I get the feeling that most people here are arguing against these sorts of possibilities not because they know a whole lot about it, but because they are getting defensive; they think that their science is being attacked. These sorts of questions are the heart of scientific exploration. If you can't ask the hard questions then you shouldn't be talking about science at all.

Originally Posted by slash112

But protons aren't particles. (i.e. the 90% that hits the earth)

Protons are particles. A single proton has another name, hydrogen ion. Perhaps you were thinking photon? You would still be wrong since those are particles too but I would understand the mix up a little better.

Originally Posted by Xaqaria

The cosmic ray argument is refuted by the simple fact that if cosmic rays were to create a miniature black hole in our atmosphere (and it didn't immediately decay), its momentum would carry it through the earth and out the other side, off into the void of space. A black hole created by a particle accelerator would start out relatively stationary and so would get trapped in earth's gravitational field.

I get the feeling that most people here are arguing against these sorts of possibilities not because they know a whole lot about it, but because they are getting defensive; they think that their science is being attacked. These sorts of questions are the heart of scientific exploration. If you can't ask the hard questions then you shouldn't be talking about science at all.

I call shenanigans.

Micro black holes haven't yet been observed, they're a theoretical prediction. In spite of that, the idea that the we may accidentally create those micro black holes is purely speculative, because theoretically the LHC is not even close to being able to produce them.

Given the variety of possible collision scenarios for cosmic rays, there are plenty of imaginable situations where the relative speeds would result in not so fast moving black holes, add to the fact that the formed micro black hole would also be affected by electromagnetic forces. And any black hole that escaped the Earth would still have to deal with the Sun and our other neighbours.

Originally Posted by Xaqaria

The cosmic ray argument is refuted by the simple fact that if cosmic rays were to create a miniature black hole in our atmosphere (and it didn't immediately decay), its momentum would carry it through the earth and out the other side, off into the void of space. A black hole created by a particle accelerator would start out relatively stationary and so would get trapped in earth's gravitational field..

Do you have proof that cosmic rays can pass through the Earth? Momentum is mass x velocity, so a proton, no matter how fast it is traveling will never have much momentum because it has so little mass. Getting through the atmosphere is one thing, but the entire Earth...

A miniature black hole created by cosmic ray particles is not the same thing as a cosmic ray particle. If (and lets be clear that it is a big if) cosmic rays were to create a miniature black hole, the black hole that is created would be significantly smaller than the particles that interacted to create it. It would pass through the earth in much the same way that neutrinos do, since it would be so small that it would hardly interact with anything at all. I'd also like to point out that this is all theory, both the existence of miniature black holes, and whether or not they would decay near instantaneously or persist. I started this all by saying that the LHC is theoretically capable of imploding the earth. The prediction is based on several versions of string theory that require extra dimensions of space, without which much more energy would be required to create a miniature black hole and therefore it wouldn't be possible to do with the LHC at all.

Originally Posted by Xaqaria

A miniature black hole created by cosmic ray particles is not the same thing as a cosmic ray particle. If (and lets be clear that it is a big if) cosmic rays were to create a miniature black hole, the black hole that is created would be significantly smaller than the particles that interacted to create it. It would pass through the earth in much the same way that neutrinos do, since it would be so small that it would hardly interact with anything at all. I'd also like to point out that this is all theory, both the existence of miniature black holes, and whether or not they would decay near instantaneously or persist. I started this all by saying that the LHC is theoretically capable of imploding the earth. The prediction is based on several versions of string theory that require extra dimensions of space, without which much more energy would be required to create a miniature black hole and therefore it wouldn't be possible to do with the LHC at all.

OK, so say all this is correct and the micro black holes don't dissipate, how do you propose they are a danger to the Earth given their extreme low mass?

Originally Posted by Xaqaria

Protons are particles. A single proton has another name, hydrogen ion. Perhaps you were thinking photon? You would still be wrong since those are particles too but I would understand the mix up a little better.

I meant to say "photons"... I thought that is what the source said. But I guess it didn't say that... But I think it should say that...