I'm a total laymen so I appreciate all the technical posts, I am attempting to decipher through them. I guess my question is, if this is so ridiculous of a conjecture "vacuum metastability disaster events", Then why do they fuel so much argument? Also, Why does LSAG pay so little attention to it? Is it that ridiculous that something we do not understand could occur? Yes these CR collisions involving PB occur throughout the galaxy but we have never seen it, we also do not know the actual effects as the disaster could be traveling to us at the speed of light? Are any of you even a little worried about this or mBH or Strangelets or Runaway Killer Acorns? I mean 1 in a quadrillion worried? I find it super precarious and worrisome that the LSAG reports barely note on this. The RHIC safety report cites the highest observed heavy ion collision in nature meassured up to 2.6 Tev, RHIC safety assesment group claims to be the upper limit. We will be doubling that on the next run in the LHC... Ring the Alarm? Why would they not update the safety reports? Vacuum bubbles supposed to be created at immense energies at center mass of collisions - and as we all agreed under "optimal" collisions, Pb-Pb could reach over 1,000 TeV. When they created quark gluon plasma at BNL previously didn't that go against the standard model of physics? If so, isn't more deviating things possible when they increase the beam energies at LHC?
Ok, well, in an obvious attempt to redeem myself, what I said was . . . which I based on what's known about the strength of magnetic fields at the surface, the LHC produces magnetic fields which are much weaker. And I recall reading something about the LHC collision energies being close to those near the first few seconds of the big bang, or something. The collision energies, not the beam energies . . .
The same reason that the "nutty" conspiracy theorists fuel so much argument and denial on such Impossible claims as 9/11 being an inside job, or that the Apollo Moon landings were faked. I'm also a layman, but it seems so far to me at least that you have been given reputable answers from reputable people, as to the viability of these claims.
Two points I may need some clarification on the above. First, if as it seems you are saying the energy added by the collider is far greater than the combined energy of the debris after a collision, that alone should resolve hahnaz's fears. There would be no excess energy available to cause havoc with, the ground state of the universe. There is one point that is still bothering me. And I don't believe it is critical to the OP. In a normal fission event, it takes less energy to break an atom and its neucleus apart, than the resulting energy released during that process. The LHC is working with very small mass when it collides heavy ions, even when compared to a controlled process in a reactor, but it sounds like you are saying, that none of the initial mass of the ion, is converted to, or released as additional energy..? Even assuming that a significant part of the energy released during the fission of whole atoms, which includes breaking the electron nucleus binding energy (for want of better words), I always assumed that some part of the energy released does come from splitting the neucleus itself. Some small part of the initial mass is transformed into energy... So the question is, Is there is no mass energy conversion that occurs during a heavy ion collision?.. It really is just book keeping the kinetic energies prior to and after collision?
You may not be able to resolve hahnaz's fears. Since his fear seems unreasonable then reason will not be able resolve it. I hope I am incorrect about this.
No, the energy added by the collider is almost completely equal to the sum of the energy of the debris. Rest Mass-Energy of Nuclei + Kinetic Energy (Nuclei) = Energy Before Collision = Energy After Collision = Rest Mass-Energy of Debris + Kinetic Energy (Debris) That's the relativistic generalization of the high school-taught concept of conservation of energy. For any free particle the following principal and derived relations between energy, E; momentum, p; velocity, v; and rest-mass, m hold: \( E^2 = \left( mc^2 \right)^2 + \left( \vec{p} c \right)^2 \\ E \vec{v} = c^2 \vec{p} \\ \begin{array}{c|c} m = 0 & m > 0 \\ \hline \\ \left| \vec{v} \right| = c & \left| \vec{v} \right| = \frac{ \sqrt{ \gamma^2 - 1 }}{\gamma} c \\ E = c \left| \vec{p} \right| & E = \gamma m c^2 \\ & \vec{p} = \gamma m \vec{v} \\ & \gamma = \frac{1}{\sqrt{1 - \frac{\vec{v}^2}{c^2}}} \end{array}\) So if you decompose Energy for a single particle into rest mass-energy and kinetic energy, we have: \(E = mc^2 + \left{ \begin{array}{lcr} c \left| \vec{p} \right| & \quad \quad \quad & \textrm{if} \; m = 0 \\ \frac{1 - \sqrt{1 - \frac{\vec{v}^2}{c^2}} }{\sqrt{1 - \frac{\vec{v}^2}{c^2}}} mc^2 & & \textrm{otherwise} \end{array} \right.\). Since \( \gamma^{-1} = \sqrt{1 - \frac{\vec{v}^2}{c^2}} << \frac{1}{2}\) for LHC protons and nuclei, the ratio of kinetic energy to rest energy\( (\gamma -1) : 1\) is much larger than 1 :1. What should calm hahnaz's fears specific to Pb-Pb collisions is that the nucleus benefits from the LHC addition of kinetic energy because the nuclei shares a state of motion. Thus the gamma factor is applied individually to all of it's pieces and since only pieces of nucleons (patrons) actually collide due to asymptotic freedom, the energy available to explore new-to-humanity physics collisions in Pb-Pb collisions is lower than in the p-p collisions that the LHC is able to propel to higher values of gamma with the same magnet configuration. What should calm hahnaz's fears specific to vacuum collapse is even in p-p collisions the natural cosmic ray-stationary proton collision flux and cosmic ray-cosmic ray collision flux are at higher energies than LHC events and the vacuum hasn't collapsed and the electroweak unification hasn't settled into a new regime in 13.7 billion years in a volume of space measured in octillions of cubic light years. The Mandelstam variable s is defined as \(s = (E_1 + E_2)^2 - c^2 \left( \vec{p}_1 + \vec{p}_2 \right)^2 = m_1^2 c^4 + m_2^2 c^4 + 2 ( E_1 E_2 - c^2 \vec{p}_1 \cdot \vec{p}_2 ) \) So if \(m_1 = m_2 = m'_1 = m'_2 = m > 0, \; \vec{p}_1 = - \vec{p}_2, \; \vec{p}'_2 = 0\) then we have: \(s = 4 \gamma^2 m^2 c^4, \; s' = \left[ (\gamma' + 1)^2 - ( \gamma'^2 - 1 ) \right ] m^2 c^4 = 2 ( \gamma' + 1 ) m^2 c^4 \) so \(s = s'\) in this case means \(2 \gamma^2 - 1 = \gamma'\) or \(\gamma = \sqrt{ \frac{ \gamma' + 1}{2} }\). So for the LHC design criteria of \(\sqrt{s_{NN}} = 14 \textrm{TeV}\), so we only need consider \(\gamma < 7461\) so for the equivalent cosmic ray proton hitting a stationary proton, \(\gamma' < 111333041\) and \(E'_1 < 104500 \textrm{TeV} = 0.1045 \textrm{EeV} \). Are you referring to spontaneous fission \(_{Z}^A X \quad \rightarrow \quad _{Z_1}^{A_1} X \; + \; _{Z_2}^{A_2} X \; + \dots + \textrm{Energy}\) or stimulated fission \(_0^1n \; + \; _{Z}^A X \quad \rightarrow \quad _{Z_1}^{A_1} X \; + \; _{Z_2}^{A_2} X \; + \dots + \textrm{Energy}\). All of these reactions conserve the numbers of neutrons and protons, so the energy (~ 200 MeV/fission for U235) comes because the daughter nuclei have more negative total binding energy than the original parent nucleus. Thus the energy of the left side equals the energy of the right side. 200 MeV is tiny when typically the rest mass-energy of the left side is 1000 times that. The collisions at the LHC may not conserve the number of neutrons or protons due to weak interactions that don't apply to nuclear fission, but empirically they obey the law of conservation of baryon number, so ultimately the expectation is that each of the 416 baryons in the Pb-Pb collision will have a counterpart 416 baryons expected in the cooled debris. But that was not my point. My point was that even if a matter-to-energy process that violated conservation of baryon number existed, that would be nearly insignificant to the energy balance of the experiment. At best it would be the difference between gamma = 3000 and gamma = 3001. Only the most precise measurements could possibly detect any extra energy from direct mass-to-energy transmutation. The rest energy is mc² but the kinetic energy is (γ−1) mc². No, you only get energy out of splitting even a meta-stable nucleus if you reassemble the fragments into more stable configurations. The LHC does not reassemble nuclei -- it smashes them utterly. There is plenty of energy-to-mass conversion in that the kinetic energy is transformed into the rest mass of newly unbound nucleons which as you recall mass more than the bound nucleus. Likewise the creation of matter-antimatter pairs happens a lot and that's as direct energy-to-mass conversion that we know. Then there will be fundamental particle decays and annihilations which are again mass-to-energy conversions. But all the energies before total the same as all the energies after, and the bulk of the energies before are the kinetic energy added by accelerating the nuclei up to near light speed.
Thanks for taking the time to put that together. I never paid close attention to the details of some of what you just explained, in the past. I was thinking more of stimulated fission, but I see your point. That would make the energy released in a reactor or bomb a change in binding energy? Rather than a direct conversion of particle mass to energy? I hope that's right, I have only read it through quickly and the math takes me a while to make sense of. Any way, thanks again for taking the time and effort.
Err, no, that was me replying to OnlyMe. Drawing a very long bow in trying to compare apples - LHC focusing magnet fields, with oranges - those applying to presumably solar prominences - wouldn't you sayPlease Register or Log in to view the hidden image!? It's true the B fields involving the latter aren't static fields which cannot alter particle energies, but are a feature of plasma coupled systems. Involving dynamical collapse and reconnection processes that do accelerate particles (coronal ejections, solar storms). Maximum particle energies so produced are comparatively very mild: https://en.wikipedia.org/wiki/Solar_flare#Cause Around 10 Mev i.e. 10^-5 TeV which is much higher than mean energies in core but vastly less than for pending LHC Pb-Pb direct hits. Hot BB remains far and away the big daddy event relevant here. Too bad none of this seems to calm hahnaz.
Sorry! Just noticed one of the math sections didn't typeset. Too late to fix it above. Also, the relations that give v on the left side both derive from: \(\left| \vec{v} \right| = \frac{\sqrt{E^2 - \left( mc^2 \right)^2}}{E} c\) \(E = mc^2 + \left\{ \begin{array}{lcl} c \left| \vec{p} \right| & \quad \quad \quad & \textrm{if} \; m = 0 \\ \frac{1 - \sqrt{1 - \frac{\vec{v}^2}{c^2}} }{\sqrt{1 - \frac{\vec{v}^2}{c^2}}} mc^2 & & \textrm{otherwise} \end{array} \right. \). Since \( \gamma^{-1} = \sqrt{1 - \frac{\vec{v}^2}{c^2}} << \frac{1}{2}\) for LHC protons and nuclei, the ratio of kinetic energy to rest energy\( (\gamma -1) : 1\) is much larger than 1 :1.
Thank you all for helping me out. This math is super complicated and I am still trying to push through it but you guys have all been a great help. It is a total disservice that one of the fear mongers keeps messaging me on facebook bringing up "concerns". I really appreciate all the help.
Very informative. Thanks for writing that down for everybody. A working example for the relativistic energy equation.
One (almost) sure way to settle it in your mind would be to challenge that fear monger to sign up and post here in this thread. If he/she has the guts to do that; we'll see how long it takes before there is an admission of basic error by said fear monger. If no such willingness is forthcoming, you can draw the obvious conclusion.
You can't debate the intellectually dishonest and expect to agree on the outcome of the debate. Without intellectual honesty, sides need not agree on what constitutes reasonable doubts of the safety of the LHC. And without the restriction of discussed doubts to just reasonable ones, one may always fall victim to the invocation of the magic of Luddite gods destroying the universe in a fit of pique when man crosses an unevidenced metaphorical line in the sand. No scientific theory is every proven in a mathematical sense. No logical proof exists that proves a negative. Therefore it is unreasonable to demand absolute proof of the LHC's safety if one is allowed to posit unicorns and black holes that don't obey any laws of physics. The conservation of mass-energy, the conservation of angular momentum, the lack of dependency on physical laws on position, choice state of rest or human involvement are solid principles founded on empirical observation. We don't throw them out when we determine if a communicated doubt is a reasonable one or not. We don't allow people to play at "risk evaluation" and multiply made-up probabilities of catastrophe with made-up measures of damages from catastrophe (usually infinity). That's just aping the form of risk evaluation without the substance. It's not reasonable, but it's the modus operandi of the fear merchants. We should not allow them to try and substitute arithmetic on made-up numbers for actual reasoned argument on the merits for those numbers.
But what can and in this case probably should be done is to coax the panic merchant(s) to front up in an open debate setting, and then have them paint themselves into a corner from which they cannot offer any sane means to escape from. After all, the onus of proof, against all the overwhelming contrary evidence already given here, will be on such. If it leads to even just one or two to break free of FUD (fear, uncertainty, and doubt), worth the effort to try imo.
Reasonable is a scary term, considering many of CERN's scientists are on record usually stating "This could shatter everything we understand about physics", "This could completely change our ideas of the standard model". I am a laymen, I also do have an appreciation of science. I understand that no known or proven physics could state this experiment as remotely dangerous, but we simply would not know until we do it. Neutronstars, how sure are we that there isn't a gravity field that deflects the Cosmic Rays? What if the core is a super fluid and it keeps the mBH from acreting mass (Greg Stewart: Greg Stewart Please Register or Log in to view the hidden image!oes a White Dwarf or Pulsar have an atmosphere? Do they already have a singularity at thier core thats at a stable local matter equalibrim? Nobody knows, but's possible every star has a black hole at their core thats responsible for a part of it's fusion process. For all we know there could already be one at the earths core I don't think anyone has considered this.) How do we know for sure? I'm sorry but I guess I believe in science, I'm more worried maybe their something we've overlooked. Something we do not understand (For example blackholes do not acrete in Neutron Stars for some reason).
When scientists at CERN say things like you quoted above they are most often talking about things that improve on existing theory, not things that might destroy the universe or even just the LHC. Before doing any experiment at the LHC or any other collider, the proposed experiment has to be approved, by a group overseeing the operation of the collider. Part of that review does involve safety. They are not going to allow any collision experiment that is more dangerous than running the collider itself, go forward. They look not only at the kind of danger you are afraid of, but also any possible damage to the collider the experiment might cause. Most of the above is the result of commingling or confusing, science fiction and science. It is science fiction, masquerading as science and prompted by persons who don't understand the science and/or have other reasons to insight fear in others. We do know a great deal about how gravity affects mass/matter. It is from what we do know about gravity, that we do know there are no black holes at the center of planets, stars.., even neutron stars. While we do have some observational evidense that supports the prediction that black holes exist, what we know about gravity that leads to the prediction of black holes, also excludes the possibility that any black hole might exist inside any star of any kind. QUOTE="hahnaz, post: 3288198, member: 282297"][I'm sorry but I guess I believe in science, I'm more worried maybe their something we've overlooked. Something we do not understand (For example blackholes do not acrete in Neutron Stars for some reason).[/QUOTE] There are many things we have overlooked and many things we do not (yet) fully understand. Your last comment above I do not understand. The universe has been around for a very long time. On the order of 14.7 billion years. We have been walking upright, as human beings for a little less than 200,000 years.., give or take? The fact that we now have the ability to be aware of the greater universe, does not increase the likelyhood that it will come to an end anytime soon. Hahnaz, you have already been given a great deal of reason not to believe the scaremongering, you have been questioning (or presenting) here. There is nothing anyone is doing at the LHC or anywhere else, that comes even close to the many many high energy events that have occurred throughout the universe in the past.., and likely continue in the present. We pose a greater threat to ourselves, than we do to the existence of even the planet we stand on, let alone the universe as a whole. What this really boils down to is a fear of the unknown, much like a child's fear of the dark and monsters... Stop listening to anyone who is not a credible physist, even when they use quotes out of context from physists.
There are many things we have overlooked and many things we do not (yet) fully understand. Your last comment above I do not understand. What this really boils down to is a fear of the unknown, much like a child's fear of the dark and monsters... Stop listening to anyone who is not a credible physist, even when they use quotes out of context from physists.[/QUOTE] What I meant was, Neutron Stars serve as the crux of the safety argument. If cosmic rays slam into Neutron Stars and they do not get gobbled up then that must mean these collisions are safe. Even if mBH do not evaporate, clearly nothing wrong could happen because they would get stuck in a Neutron Star and we see that nothing occurs. That is the logic behind the safety of the LHC. My only argument would be, what if we are missing a piece of the puzzle? Maybe the core of a Neutron Star is immune to blackhole accretion of some sort. WE DO NOT KNOW.
A Neutron star does not have a BH at its core. If it did the Neutron star would be consumed and all we would have is a BH. A Neutron star has a mass about 3 times that of the Sun, compacted to about the size of a city, with about the same density as an atomic nucleus. A Neutron star can turn into a BH by accreting more mass to surpass this 3 Solar mass limit and collapsing under gravity to its Schwarzchild radius at which point an EH is formed and we have a BH. http://hyperphysics.phy-astr.gsu.edu/hbase/astro/blkhol.html We also understand pretty well the fusion process, without any need to imagine a BH at the cores of stars. For your information, although BHs by their very definition can never be seen, they are logically deduced by their effects on matter/energy and spacetime within their vicinity. Cosmologists do not know everything, but they know enough to totally discount any possibility of what you have mentioned re BHs and the other bits of scare mongering that some see the need to undertake to try and impress people.
I was not saying that the core of a Neutron Star but what if it is some sort of magnetic or energy field that prevents the mBH from gaining mass. This would in turn invalidate the safety argument of CRs. I'm just saying there may be a few things we don't understand.
