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The LHC just doubled it's power. While only operating at 50% it discovered several new particles including the Higgs Boson. Now that it's nearing 100% they're

The LHC just doubled it's power. While only operating at 50% it discovered several new particles including the Higgs Boson. Now that it's nearing 100% they're hoping to discover physics beyond the Standard Model. That could include things like additional spatial dimensions, Dark Matter, microscopic black holes and more. TLDR: Hopefully opening the door for some mind blowing discoveries.

noobermin 12y ago
To expand upon what you're saying for the grandparent, what you have is one beam of protons can reach the kinetic energy of 6.5 TeV. They will circulate a second beam at the same energy, and collide them head on. Thus, the "center-of-momentum" energy, that is, the energy involved in a collision of one proton from one beam hitting another from the other beam will be 13 TeV at max. Often times, physicists refer to this energy by the symbol "s". Basically, energy and mass are interchangeable in some violent reactions (like the ones at the LHC or that released in atomic explosions) as we know because of Einstein. This means that as we increase the energy of these violent collisions, the more energy that is available to be converted into the mass of possible particle products. It should be noted that it isn't like we add mass to the products like adding snow to a snow ball, it isn't a continuum. It's more like a threshold. If a particle has a mass of 938 MeV, say, we will see it in a collision as a product only if s for that interaction is greater than 938 MeV. In fact, it must be a bit larger than this, because while some energy gets converted to mass, some energy also needs to get converted to energy of motion for these products too. Otherwise, they won't reach our the detectors in our apparatus for us even to see them. We haven't seen a number of massive particles we think should exist, from a theory called "Supersymmetry". Note that we do not really know from theory what these masses should be, but we need them to exist for our current models of the universe. Our current guess then for why we don't see them is that we just haven't passed their threshold masses sufficiently to create them first and with enough energy after in order to see them. That's why 6.5 TeV which implies a max s of 13 TeV is important. It's like we've increased the range of our "scan" of particle masses. It means we'll produce more massive particles (if they exist) and more of them in number with sufficient energy to actually see them.
- krohling 12y ago
  This is a great explanation. One other bit I'll add is that the particles they're colliding are protons, which are made of other particles, called quarks. While the protons are colliding with a relative energy of 13TeV (or will be) the actual collision energy depends on the collision angle of the quarks inside the proton. If it's a glancing collision, which it almost always is, the actual collision energy is much lower. In other words, we don't get to make particles w/ masses of 13TeV. The Higgs for reference has a mass of 125 GeV. That's one reason physicist are considering using Muons in future accelerators instead of protons. They're not made of other stuff. One of my favorite videos on this topic was a Great Courses video by Sean Carroll. Well worth the $40. http://www.thegreatcourses.com/courses/the-higgs-boson-and-beyond.html http://www.thegreatcourses.com/courses/the-higgs-boson-and-b...
  - noobermin 12y ago
    This is a very crucial point. Unfortunately, I cannot edit my post to point to it.
  - iwwr 12y ago
    There's also a free mini-course by David Butler https://www.youtube.com/playlist?list=PLpH1IDQEoE8Q8842yVe-V8m7PN-R9rlwi https://www.youtube.com/playlist?list=PLpH1IDQEoE8Q8842yVe-V... It goes into a little more detail than a typical popularizing course, but enough even for laypeople to understand. David Butler also has a great introduction to astronomy in the same style: https://www.youtube.com/playlist?list=PLpH1IDQEoE8QWWTnWG5cK4ePCqg9W2608 https://www.youtube.com/playlist?list=PLpH1IDQEoE8QWWTnWG5cK...
- hardcandy 12y ago
  I learned more from this comment than from my entire high school physics class.
- raverbashing 12y ago
  > If a particle has a mass of 938 MeV, say, we will see it in a collision as a product only if s for that interaction is greater than 938 MeV Just as a comment, we "only" saw the Higgs Boson (around 125GeV) at LHC energy levels, so the Higgs might get produced at small collision energies, but with a much lower probability (I'm not disagreeing with you btw)
TallGuyShort 12y ago
Microscopic black holes scares me. I once heard (entirely anecdotal - I'd love it if someone more knowledgeable on the subject could comment) they had calculated the probability that the LHC would create a black hole that consumed the Earth. The result was more likely than SHA1-hash collision, and was deemed safe enough to try. Somewhere between humorous and scary. edit: did some Googling and found some documentation (https://en.wikipedia.org/wiki/Safety_of_high-energy_particle_collision_experiments https://en.wikipedia.org/wiki/Safety_of_high-energy_particle...). It cites an estimated upper limit of 1 in 50 million and references the book in which that estimate is made.
- davesque 12y ago
  I can't see how this would be a problem even if a black hole was created. A black hole is no different than any other massive object in that it doesn't exert any stronger pull than its mass allows for. In other words, if the Sun suddenly turned into a black hole right now, we would not get "sucked" into it. The Earth would continue orbiting at the same period and distance. Of course, it would suck (no pun intended) not to have sunlight but hey, maybe the energy emitted by the accretion disc would equal the energy output of the sun :P! Of course, an accretion disc would probably take a while to form, so we would probably be fucked anyway, but certainly not because we would be sucked into the black hole. Similarly, if the LHC created a black hole through its collisions, I can't see how it would be that massive. If it's not very massive, then it's not a threat. In fact, there are theories that support the notion that it would evaporate rather quickly (via Hawking radiation). Of course, I don't have any numbers on this and only have a laymen's knowledge of the physics involved. Anyone care to comment with more info?
  - maxerickson 12y ago
    If it doesn't evaporate, it would (slowly at first) absorb the Earth. We might not get pulled in anytime soon, but it would sort of be a bummer for the future if the planet was destroyed in the next few thousand years. (I don't think I have an interesting opinion when it comes to the question of whether such a hole would evaporate or not, but the question of why having a blackhole on the surface of the planet is bad is easier to think about)

noobermin 12y ago

To expand upon what you're saying for the grandparent, what you have is one beam of protons can reach the kinetic energy of 6.5 TeV. They will circulate a second beam at the same energy, and collide them head on. Thus, the "center-of-momentum" energy, that is, the energy involved in a collision of one proton from one beam hitting another from the other beam will be 13 TeV at max. Often times, physicists refer to this energy by the symbol "s". Basically, energy and mass are interchangeable in some violent reactions (like the ones at the LHC or that released in atomic explosions) as we know because of Einstein. This means that as we increase the energy of these violent collisions, the more energy that is available to be converted into the mass of possible particle products. It should be noted that it isn't like we add mass to the products like adding snow to a snow ball, it isn't a continuum. It's more like a threshold. If a particle has a mass of 938 MeV, say, we will see it in a collision as a product only if s for that interaction is greater than 938 MeV. In fact, it must be a bit larger than this, because while some energy gets converted to mass, some energy also needs to get converted to energy of motion for these products too. Otherwise, they won't reach our the detectors in our apparatus for us even to see them. We haven't seen a number of massive particles we think should exist, from a theory called "Supersymmetry". Note that we do not really know from theory what these masses should be, but we need them to exist for our current models of the universe. Our current guess then for why we don't see them is that we just haven't passed their threshold masses sufficiently to create them first and with enough energy after in order to see them. That's why 6.5 TeV which implies a max s of 13 TeV is important. It's like we've increased the range of our "scan" of particle masses. It means we'll produce more massive particles (if they exist) and more of them in number with sufficient energy to actually see them.

krohling 12y ago
This is a great explanation. One other bit I'll add is that the particles they're colliding are protons, which are made of other particles, called quarks. While the protons are colliding with a relative energy of 13TeV (or will be) the actual collision energy depends on the collision angle of the quarks inside the proton. If it's a glancing collision, which it almost always is, the actual collision energy is much lower. In other words, we don't get to make particles w/ masses of 13TeV. The Higgs for reference has a mass of 125 GeV. That's one reason physicist are considering using Muons in future accelerators instead of protons. They're not made of other stuff. One of my favorite videos on this topic was a Great Courses video by Sean Carroll. Well worth the $40. http://www.thegreatcourses.com/courses/the-higgs-boson-and-beyond.html http://www.thegreatcourses.com/courses/the-higgs-boson-and-b...
- noobermin 12y ago
  This is a very crucial point. Unfortunately, I cannot edit my post to point to it.
- iwwr 12y ago
  There's also a free mini-course by David Butler https://www.youtube.com/playlist?list=PLpH1IDQEoE8Q8842yVe-V8m7PN-R9rlwi https://www.youtube.com/playlist?list=PLpH1IDQEoE8Q8842yVe-V... It goes into a little more detail than a typical popularizing course, but enough even for laypeople to understand. David Butler also has a great introduction to astronomy in the same style: https://www.youtube.com/playlist?list=PLpH1IDQEoE8QWWTnWG5cK4ePCqg9W2608 https://www.youtube.com/playlist?list=PLpH1IDQEoE8QWWTnWG5cK...
hardcandy 12y ago
I learned more from this comment than from my entire high school physics class.
raverbashing 12y ago
> If a particle has a mass of 938 MeV, say, we will see it in a collision as a product only if s for that interaction is greater than 938 MeV Just as a comment, we "only" saw the Higgs Boson (around 125GeV) at LHC energy levels, so the Higgs might get produced at small collision energies, but with a much lower probability (I'm not disagreeing with you btw)

TallGuyShort 12y ago

Microscopic black holes scares me. I once heard (entirely anecdotal - I'd love it if someone more knowledgeable on the subject could comment) they had calculated the probability that the LHC would create a black hole that consumed the Earth. The result was more likely than SHA1-hash collision, and was deemed safe enough to try. Somewhere between humorous and scary. edit: did some Googling and found some documentation (https://en.wikipedia.org/wiki/Safety_of_high-energy_particle_collision_experiments https://en.wikipedia.org/wiki/Safety_of_high-energy_particle...). It cites an estimated upper limit of 1 in 50 million and references the book in which that estimate is made.

davesque 12y ago
I can't see how this would be a problem even if a black hole was created. A black hole is no different than any other massive object in that it doesn't exert any stronger pull than its mass allows for. In other words, if the Sun suddenly turned into a black hole right now, we would not get "sucked" into it. The Earth would continue orbiting at the same period and distance. Of course, it would suck (no pun intended) not to have sunlight but hey, maybe the energy emitted by the accretion disc would equal the energy output of the sun :P! Of course, an accretion disc would probably take a while to form, so we would probably be fucked anyway, but certainly not because we would be sucked into the black hole. Similarly, if the LHC created a black hole through its collisions, I can't see how it would be that massive. If it's not very massive, then it's not a threat. In fact, there are theories that support the notion that it would evaporate rather quickly (via Hawking radiation). Of course, I don't have any numbers on this and only have a laymen's knowledge of the physics involved. Anyone care to comment with more info?
- maxerickson 12y ago
  If it doesn't evaporate, it would (slowly at first) absorb the Earth. We might not get pulled in anytime soon, but it would sort of be a bummer for the future if the planet was destroyed in the next few thousand years. (I don't think I have an interesting opinion when it comes to the question of whether such a hole would evaporate or not, but the question of why having a blackhole on the surface of the planet is bad is easier to think about)