The proton rest mass of about 1GeV is 1.67x10^-27 kg the Schwarzschild Radius (Rs) of a black hole of a proton mass is then 2.48x10^-54 m. Now the total center of mass energy in the LHC is 14 TeV = 14,000 Gev so if ALL the center of mass rest energy were to enter the black hole (which is NOT possible - only a small fraction of the energy would go into the black hole), then the Rs of the 14TeV Black Hole would be 14,000 x 2.48 x 10^-54 m = 3.47 x 10^-50 m. Now for a quark to enter into the black hole, it would need to hit it almost head on -- so to be generous let's increase the radius by a factor of 10 to give Rs = 2.47 x 10^-49 m. But the radius of proton is 1.53 x 10^-18 m and there are only 3 quarks in a proton and maybe an average of 3 gluons. So the probability that this black hole would absorb one quark or gluon from a proton that it passes through would be Pr = (3 quarks + 3 glouns) * R(BH) ^ 2 / R(Proton) ^ 2 = 1.5 x 10^-61. Now there are only something like 10^+79 protons and neutrons in the entire observable universe and a measly 10^+51 protons and neutrons in the entire earth, so this black hole would have to pass through all the protons and neutrons in 10 billion earth masses before it would absorb one quark on average.
Indeed, since these tiny black holes hardly ever interact with matter, they could constitute the dark matter needed in cosmology - but ONLY if they do not evaporate.
I agree that these black holes are not a problem. Another argument that may convince some of you is the following:
Cosmic rays of MUCH higher energy than the LHC hit the earth's atmosphere all the time. If the LHC does create a black hole you can be absolutely sure that MANY MANY black holes have been created over the 4.5 billion years since the earth formed. So if a black hole is at all dangerous, the earth would have been already experience the black hole disaster. So since the earth is still here after 4.5 billion years that is proof that any black holes that the LHC could create will not be at all dangerous.
Even if the theory that these sub-microscopic black holes quickly evaporate is wrong. the previous argument still holds - they cannot be dangerous since otherwise the cosmic rays would have already created many of these holes and the earth would already have been destroyed. Basically these black holes would be so much smaller than a proton that it would easily pass through even a proton with only a extremely small chance it would absorb a quark from the proton.
This is NOT a problem. Cosmic rays of MUCH higher energy than the LHC hit the earth's atmosphere all the time. If the LHC does create a black hole you can be absolutely sure that MANY MANY black holes have been created over the 4.5 billion years since the earth formed. So if a black hole is at all dangerous, the earth would have been already experience the black hole disaster. So since the earth is still here after 4.5 billion years that is proof that any black holes that the LHC could create will not be at all dangerous.
True, it is "only" a theory that these sub-microscopic black holes will evaporate in a very short time - since they have never been observed - but it is a very well accepted theory. Even if the theory is wrong, and these sub-microscopic black holes do not evaporate, the previous argument still holds - they cannot be dangerous since otherwise the cosmic rays would have already created many of these holes and the earth would have been destroyed. Basically these black holes would be so much smaller than a proton that it would easily pass through even a proton with only a extremely small chance it would absorb a quark from the proton.
I have never understood why anywone would want to save their previous search queries. The search strings themselves are usually not very long so it is not to save laborious typing. What is it for? I understand why the search engines want to save all search strings, but why would I, a user, ever want to review or re-search my previous queries? I do not care what I searched for a week, a month or a year ago, so would someome who cares please explain it to me? Thanks.
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Here are a few calculations:
The proton rest mass of about 1GeV is 1.67x10^-27 kg the Schwarzschild Radius (Rs) of a black hole of a proton mass is then 2.48x10^-54 m. Now the total center of mass energy in the LHC is 14 TeV = 14,000 Gev so if ALL the center of mass rest energy were to enter the black hole (which is NOT possible - only a small fraction of the energy would go into the black hole), then the Rs of the 14TeV Black Hole would be 14,000 x 2.48 x 10^-54 m = 3.47 x 10^-50 m. Now for a quark to enter into the black hole, it would need to hit it almost head on -- so to be generous let's increase the radius by a factor of 10 to give Rs = 2.47 x 10^-49 m. But the radius of proton is 1.53 x 10^-18 m and there are only 3 quarks in a proton and maybe an average of 3 gluons. So the probability that this black hole would absorb one quark or gluon from a proton that it passes through would be Pr = (3 quarks + 3 glouns) * R(BH) ^ 2 / R(Proton) ^ 2 = 1.5 x 10^-61. Now there are only something like 10^+79 protons and neutrons in the entire observable universe and a measly 10^+51 protons and neutrons in the entire earth, so this black hole would have to pass through all the protons and neutrons in 10 billion earth masses before it would absorb one quark on average.
Indeed, since these tiny black holes hardly ever interact with matter, they could constitute the dark matter needed in cosmology - but ONLY if they do not evaporate.
So, once again, don't worry...
I agree that these black holes are not a problem. Another argument that may convince some of you is the following:
Cosmic rays of MUCH higher energy than the LHC hit the earth's atmosphere all the time. If the LHC does create a black hole you can be absolutely sure that MANY MANY black holes have been created over the 4.5 billion years since the earth formed. So if a black hole is at all dangerous, the earth would have been already experience the black hole disaster. So since the earth is still here after 4.5 billion years that is proof that any black holes that the LHC could create will not be at all dangerous.
Even if the theory that these sub-microscopic black holes quickly evaporate is wrong. the previous argument still holds - they cannot be dangerous since otherwise the cosmic rays would have already created many of these holes and the earth would already have been destroyed. Basically these black holes would be so much smaller than a proton that it would easily pass through even a proton with only a extremely small chance it would absorb a quark from the proton.
So don't worry - be happy!
This is NOT a problem. Cosmic rays of MUCH higher energy than the LHC hit the earth's atmosphere all the time. If the LHC does create a black hole you can be absolutely sure that MANY MANY black holes have been created over the 4.5 billion years since the earth formed. So if a black hole is at all dangerous, the earth would have been already experience the black hole disaster. So since the earth is still here after 4.5 billion years that is proof that any black holes that the LHC could create will not be at all dangerous.
True, it is "only" a theory that these sub-microscopic black holes will evaporate in a very short time - since they have never been observed - but it is a very well accepted theory. Even if the theory is wrong, and these sub-microscopic black holes do not evaporate, the previous argument still holds - they cannot be dangerous since otherwise the cosmic rays would have already created many of these holes and the earth would have been destroyed. Basically these black holes would be so much smaller than a proton that it would easily pass through even a proton with only a extremely small chance it would absorb a quark from the proton.
So don't worry - be happy!
I have never understood why anywone would want to save their previous search queries. The search strings themselves are usually not very long so it is not to save laborious typing. What is it for? I understand why the search engines want to save all search strings, but why would I, a user, ever want to review or re-search my previous queries? I do not care what I searched for a week, a month or a year ago, so would someome who cares please explain it to me? Thanks.