Physicists Plan to Build a Bigger LHC 263
ananyo writes "When Europe's Large Hadron Collider (LHC) started up in 2008, particle physicists would not have dreamt of asking for something bigger until they got their US$5-billion machine to work. But with the 2012 discovery of the Higgs boson, the LHC has fulfilled its original promise — and physicists are beginning to get excited about designing a machine that might one day succeed it: the Very Large Hadron Collider. The giant machine would dwarf all of its predecessors (see 'Lord of the rings'). It would collide protons at energies around 100 TeV, compared with the planned 14TeV of the LHC at CERN, Europe's particle-physics lab near Geneva in Switzerland. And it would require a tunnel 80-100 kilometres around, compared with the LHC's 27-km circumference. For the past decade or so, there has been little research money available worldwide to develop the concept. But this summer, at the Snowmass meeting in Minneapolis, Minnesota — where hundreds of particle physicists assembled to dream up machines for their field's long-term future — the VLHC concept stood out as a favorite."
Call it... (Score:5, Funny)
the BFHC?
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Re: Call it... (Score:4, Insightful)
Big ass distractin from fusion research
I mean, the LHC was a neat project, but what practical benefits to humanity have come from it? Knowledge is great, but the Higg's discovery isn't solving the problems the world faces.
I know money and research into our energy needs could come from lots of places, but when I see massive facility of extreme high tech, employing thousands of physicists and researchers with international funding and support, and Billions of dollars budget, I can't help but think a similar problem with much greater utility is being neglected to all of our detriment.
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It's possible to do both. Besides, if your plan is "fusion at all costs", don't forget that the science involved (like computational techniques, materials science, etc...) are often cross-pollinated between the different fields.
ITER is being built in France as we speak. Construction on this hypothetical vlhc would start in the 2030s, if it happens at all.
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Anyone have Dr Who's contact number?
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The name doesn't matter, it's all about bigger bang for the buck. ;-)
No it's not. It's about spending a lot more bucks to get a bigger bang.
And the fact that the idea "stood out as a favorite" at a meeting of particle physicists is not particularly relevant. The money has to come from somewhere, and that "somewhere" is probably going to be at the expense of many other science and engineering projects.
Sure, on one level it's interesting. The probable discovery of the Higgs Boson was interesting. But if (as implied by the summary) that's really the main reason the LHC was need
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I prefer "HHC" - Humongous Hardon Collider.
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.
HAHA SUCKERS! (Score:3)
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Well, if they build the Humongous Hardon Collider, it should nicely fill the hole.
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Call me when they get to the Ludicrous Collider.
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They'll paint it plaid.
Re:Question... (Score:3)
At what percentage of C would a 100TeV proton be traveling?
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Plaid
Re:Question... (Score:4, Informative)
You hit numerical problems if you calculate it that way. Wikipedia [wikipedia.org] gives a series expansion that works well for large values of gamma:
v (in units of c) = 1 - 1/2 \gamma^(-2)
v = c (1 - 1.8e-10), or 0.99999999982 c
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I can top that if I put on my running keds.
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Re: Call it... (Score:2)
Or binary hadron collider?
Is it possible to have two circles of say same circumference each and then redirect the electron/protons to a junction between them where it can collide? With such a contraption, we can keep on revolving the protons until it reaches the required speed.
Obviously this would have been amongst the first ideas to be checked and rejected, but what are the negatives in this idea?
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One ring is enough
Yes, yes, Mr. Tolkien, we know.
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I don't think that's fair. Money Pit implies that we're throwing money in and getting nothing out.
They are using it and getting some research done. Just because the CNN isn't commenting on results every week and Slashdot isn't posting something here-and-there doesn't mean that nothing's getting done.
Dallas? (Score:4, Interesting)
hmmm....I wonder where they could build it. Oh - I know. Dallas. The tunnel has been dug so all they have to do is drop in a few magnates.
http://en.wikipedia.org/wiki/Superconducting_Super_Collider [wikipedia.org]
On a more serious note, I though the next big project was going to be a linear accelerator. Anybody know why they picked the round one over the straight one?
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hmmm....I wonder where they could build it. Oh - I know. Dallas. The tunnel has been dug so all they have to do is drop in a few magnates.
http://en.wikipedia.org/wiki/Superconducting_Super_Collider [wikipedia.org]
On a more serious note, I though the next big project was going to be a linear accelerator. Anybody know why they picked the round one over the straight one?
Slap on a little crowd sourcing and *POOF* all done.
Re:Dallas? (Score:5, Funny)
hmmm....I wonder where they could build it. Oh - I know. Dallas. The tunnel has been dug so all they have to do is drop in a few magnates.
I'm all for putting Donald Trump underground, but shouldn't we cover the hole with dirt afterwards?
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I don't know about dirt it seems to easy for zombies and action heros. Beter use cement.
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Assuming you can tell the difference between Donald Trump and cheap backfill, once you cram him, his toupee, and his ego into that hole then it's pretty much ready to be paved over.
Re:Dallas? (Score:5, Funny)
No need to fill in the hole; just comb over it.
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On a more serious note, I though the next big project was going to be a linear accelerator. Anybody know why they picked the round one over the straight one?
Isn't that simply because in a circular one you can accelerate the particles continuously through several rotations?
Re:Dallas? (Score:5, Informative)
This is true, but no so simple: in a straight line, you gain energy with the distance. When going round, you lose energy to stay in the loop as a function of the radius (the infinite radius case brings you back to the straight line). Thus, each time you want more energy, your collider ring needs to have considerably larger radius (following a third power law). At some point (basically the point after this proposal) you have to loop around the solar system :)
Re:Dallas? (Score:5, Funny)
hmmm....I wonder where they could build it. Oh - I know. Dallas. The tunnel has been dug so all they have to do is drop in a few magnates
Not sure how dropping a few billionaires into a hole in Texas would help get this project built but I'm not opposed to trying it.
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Also, in round accelerators they can achieve much higher energies, iirc, since the particles can travel around the ring many times... while in a linear accelerator its maximum energy is dictated by the length of a single run.
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The tunnels done for the SCSC are probably no longer fit for purpose, as they've been flooded ever since they were abandoned, which weakens and damages the structure considerably :(
Re:Dallas? (Score:5, Informative)
There's a tradeoff in circular/linear accelerators. Linear accelerators let you collide leptons (usually electrons) efficiently and leptons provide a MUCH cleaner signal. A comparable energy circular accelerator can be shorter, but due to bremsstrahlung losses, you have to collide hadrons (like protons), which provides a much messier signal.
After you do some rough calculations of what particles you can collide, their energies and the number of interactions per second, you then take those numbers and plug them into a model of a hypothetical detector along with a number of theories you'd like to explore to see which configuration gives you the biggest "bang for your buck"
The issue is that different people are more interested in probing different kinds of physics and it's impossible to make a detector/accelerator that's sensitive enough to fully probe everything, so big arguments happen at places like Snowmass. We know that we basically can only ask for one multi-billion dollar accelerator, so everyone's fighting to keep their pet research alive.
Re:Dallas? (Score:5, Insightful)
There are also ideas to build a circular muon collider. Muons are similar to electrons so give a nice clean signal in the detectors, but being 200 times heavier than electrons they lose much less energy as they circulate around a ring-shaped path.
The problem is muons are unstable, with a half-life of just 2 micro-seconds. But if you can collect them fast enough and accelerate them to near-light-speed, their lifetime increases due to time dilation. The nearer they get to light-speed the longer they last for, and it's thought that it would be feasible to get them going fast enough that they would last for a useful amount of time.
There are lots of advantages to circular accelerators: You can re-use the expensive accelerating sections thousands of times over by recirculating the beam; the beam itself is re-used over and over (only a tiny fraction of the particle are lost on each collision); and most importantly you can install more than one detector. Having two independent measurements is very important in establishing the reliability of any results.
Re:Dallas? (Score:5, Informative)
Muon colliders are a great concept - but they are difficult REALLY difficult. There is a significant ongoing effort to work on the technologies but they are far from ready now.
Personally I love the idea of high gradient RF cavities fabricated from Beryllium, filled with high pressure hydrogen, with megawatt high energy muon beams. There are however some possible....failure modes. Then there are the problems with neutrino radiation (I'm not kidding - it can exceed allowable dose limits).
A potentially more serious issue is that while the muon collisions themselves are very clean, the decaying muons create a huge amount of background noise in the detectors.
I think its a great project and work should continue - but like laser acceleration we can't build a machine like this yet.
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Yeah, now all they need is a shit-ton of tax dollars out of a government already $18 trillion in debt (and growing by $1 trillion a year). No problemo!! Fuck it, let's build a bunch of new Aircraft Carriers and jets while we're at it!! The party will never end, right?
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Basic research is the sea out of which major new technologies grow. Perhaps you think the West should just cede its technological dominance because it costs money to get there, but some of us see that as a form of cultural suicide.
The US is at absolutely no fucking risk of going broke. The sheer value of its human, industrial and natural resources make that just about impossible.
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Perhaps you think the West should just cede its technological dominance
Putting aside the fact that I don't see any other cultures in the world lining up to spend tens of billions on a new super-super-collider, you know what's going to be even worse than the West ceding its "technological dominance"? All the dollars in my bank account turning to dust when the U.S. government goes bankrupt, because we couldn't LIVE WITHIN OUR MEANS!!
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Actually, you don't see ANY "cultures" lining up to spend tens of billions building this, since it's only in the planning stage. When it does come time to build it there will be plenty lining up to pay for it, or have you forgotten that the US only paid for about 5% of the LHC?
Anyway, keep up the fear mongering, it's always enjoyable to read!
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The government funds itself using Monopoly game money along with the capability to print as much as they want when needed.
You just keep telling yourself that.
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With what Texas is doing to textbooks for schools, they don't deserve it.
Also, in the states, there is this trend to not fund science that does not produce an immediately marketable product.
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With what Texas is doing to textbooks for schools, they don't deserve it.
Also, in the states, there is this trend to not fund science that does not produce an immediately marketable product.
Don't pingeonhole everything in Texas. They have decent universities and a strong tech industry. Blame it on the parochial minds voting in the red districts for demanding Creationism and shit to be put in the text books. You simply do not put Dallas, Austin or Houston in the same category as some backwater county the voting majority thinks evolution is the work of the devil.
Pragmatism please. If it makes financial and scientific sense to build in in Texas, let it be. We have enough knee-jerking appeals to
Peanuts (Score:5, Interesting)
A cost of $10 billion is peanuts compared to the $3.2-4 trillion cost of the Iraq war [wikipedia.org] or the $12.8 trillion cost of the bank bailout. [unaffiliatedparty.org]. Even if these figures are not very accurate, VLHC is, comparatively, not expensive.
The trouble is that VLHC does not enrich the friends of the politicans and so will not be looked on favourably. When will mankind grow up?
Re:Peanuts (Score:4, Insightful)
The trouble is that VLHC does not enrich the friends of the politicans and so will not be looked on favourably.
Oh, yea of little faith. I'm fairly certain anything that involves land acquisition and construction contracts will benefit SOME politician somewhere.
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You should stick with the actual numbers for the bailout if you want to make a point. The imputed values distract from it.
And, the intents of these 3 expenditures is wildly different, making dollar value hard to compare.
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The trouble is that VLHC does not enrich the friends of the politicans and so will not be looked on favourably.
Maybe we should encourage Halliburton to get into the supercollider construction business?
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Yes, because we wasted a shitload of money on some other shit we can't afford makes it okay to waste a significantly smaller shitload of money on *this* shit we can't afford. "Yes honey, I know I put this Porsche on the credit card....But it's a lot cheaper than the Lamborghini I put on the credit card last month!"
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I don't see why they can't though. You still need specialized construction crews for drilling, excavating, and building the various chambers, etc, all things that people like Halliburton love to do. You still need miles and miles of copper and fiber for power and data, all things that billionaire owned communications companies would love to provide. You still need lots of sensors to be engineered and built, and then installed by contractors who make a fraction of their billable rate. I mean, I know what
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Re:Peanuts (Score:5, Insightful)
Sadly its not that simple. Imagine lab "A" says they have a design they can build for 10B and lab "B" says it will cost $11B - and assume both labs have similar good reputations for building large projects. "A" gets the project and that means they get funded for the next ~15 years. Lab B gets downsized or even shut down because the high energy physics money is going to lab A. If the project works -great. But if not, and Lab A has put in an unreasonably low estimate at least they still exist, and after 15 years many of the managers responsible have retired.
Now say 15 years later the $10B has been spent, but its not quite done, another $2B would let you finish the project. Do you really throw away $10B to save 2B? There is no fraud, just a mis-estimation of the costs of building a beyond state-of-the-art machine and slightly larger technical problems than were expected.
What happens is that you create a very strong motivation for under-estimates because that at least keeps the lab alive. Combine that with the difficulty of estimating the cost of something that hasn't been done yet, and a long enough project timescale that changing economic conditions can substantially change labor and construction costs. This is why many projects like this go over budget.
I don't think this is unique to government. I suspect that Boeing doesn't do a good job of estimating the development cost of a new airliner either - and that is much less of a technological extrapolation than the high energy physics machines.
Re:Peanuts (Score:5, Interesting)
I don't think in these cases you have multiple labs bidding for the job. You have multiple countries wanting to host the lab, but that's a different story.
The biggest problem for high energy physics is establishing multi-year funding. The US government cannot promise anything beyond a single year of funding. If say $8 B has been spent over 10 years and one year congress says "but I promised to cut spending", then that's the end of the road for that lab. This happened for the SSC in 1993, but also a lot of times since then on lower-profile, some $500 M experiments that were, yes, in construction already.
Now say 15 years later the $10B has been spent, but its not quite done, another $2B would let you finish the project. Do you really throw away $10B to save 2B? There is no fraud, just a mis-estimation of the costs of building a beyond state-of-the-art machine and slightly larger technical problems than were expected.
Most of the cases I'm familiar with, including the SSC, were not actually budget overruns even though they were politicized that way. If you're a politician who wants to (a) publicly demonstrate how fiscally conservative you are and (b) not actually cut spending on items that might affect the bulk of your constituency, then you cut big science every time. Even if the budget grows on the whole, you've made a statement and some headlines.
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If the project is hosted in the US, then labs at some level compete to be hosts. I'm only familiar with this for $1B projects, $10B may be very different.
Yes, the SSC was a combination of several things. There were techncial cost increase (not too big), increases due to delays in funding (dragging a project out costs more), and changes in what was accounted: The original number the press heard was for the machine, not the site, or the detectors, and without escalation, contingency etc. The huge numbers lat
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Dude, this would work if people were any good with numbers. Basically, if you have a competition, the best liar who low-balls their estimate gets the job. And then due to the sunk-cost fallacy, manages it to completion.
As it is, a honest estimation will only lead to your project never being funded, no matter how worthwhile it may be. And frankly, seeing the benefits of funding fundamental research, that would be immensely more costly for society in lost opportunity than whatever cost overrun. So the sociall
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Obvious troll, but I'll bite.
What weapons of mass destruction?
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What weapons of mass destruction?
Under the modern definition, a hand grenade probably qualifies as a 'weapon of mass destruction'. I'm sure Iraq had plenty of those.
Re:Peanuts (Score:5, Insightful)
I am sure I saw George Bush on the news last week, alive and well...
>and removed a shit ton of weapons of mass destruction from the world
the US military would have restocked all the weapons of mass destruction ** used in Iraq by now.
** the Boston bomber was charged with having a weapon of mass destruction, so anything pressure cooker size and up must be one
Money? (Score:2)
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Well, the numbers are all there in the summary
Cost of LHC is $5B
This one would be 3-4x as large.
So I would assume $15B-20B.
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22.5Km and just tunnels for $2B... AFAIK. [wikipedia.org]
The SSC's planned collision energy of 40 TeV is almost three times the current 14 TeV of its European counterpart, the Large Hadron Collider (LHC) at CERN in Geneva.[20]
The SSC cost was due largely to the massive civil engineering project of digging a huge tunnel underground. The LHC, in contrast, took over the pre-existing engineering infrastructure and 27 km long underground cavern of the Large Electron-Positron Collider, and used innovative magnet designs to bend the higher energy particles into the available tunnel.[21] The LHC eventually cost the equivalent of about 5 billion US dollars to build.
Yeah, we spent the money on the ISS and all we got were a bunch of virus infected computers and a tourist destination.. ;-)
Do we need a Moore's Law for particle physics? (Score:2)
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Yes. Within 10Y's, (assuming X is 2), we will need a tunnel around the equator of the earth. Within 34Y, we will need one around our solar system. Within 56Y, we will need the whole galaxy.
Why? (Score:5, Interesting)
But in planning for a future desired collision energy, they really should have some actual goal in mind to justify that design. Do they hope to find dark matter? Black holes? Do they actually think they can make the Higgs break down into something else at that energy? So... Why?
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I am not a particle physicist, but there are plenty of posited models that differ from the standard model at high energies. My understanding is that the higher energy we get, the closer we get to gravitational effects being important. Even before then, we might see something new.
Personally, I do think this level of research is starting to reach the edge of cost effective, but split between many countries the cost isn't that bad.
Re:Why? (Score:5, Insightful)
We don't yet know. Isn't that terribly exciting? That is basic research at its finest.
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It's interesting, but no, it's not particularly exciting. Pie-in-the-sky speculation isn't basic research, research (even basic research) is intended to investigate specific things - which is especially important in this multi-billion-dollar case because if you don't know what you want to look for, you can't even design the detectors to look for it.
That being said, the grandparent is as off-base as you are. Pie-in-the-sky is quite acceptable at this very early pre-preliminary stage. It gets the t
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In that case, I'd like 100 luxury, sports, and super cars. Why? We don't know yet, but it's for science! Maybe I'll crash some to see what happens, maybe I'll put some instruments on board to get readings. It truly is basic research, and at a far lower cost than the billions that a successor to the LHC will cost.
Point being, you need some justification for spending that sort of money, even if it's just a theory of some sort that you'd like to test. You can't just say "for science!" and expect governments to
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I have the same question. I am all for science and if asked I would be all for it.
But an important question should be answered if possible. What did we gain from discovering the higgs boson? I am sure there are thousands of really cool application that specialist can think of. I think if some could be highlighted (even if 50 years of engineering down the road), people would be much more receptive to it.
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There is a lot of discussion about this and the proposed machines are aimed at our best guesses of where there is new physics (for example super-symmetry).
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Well you wouldn't say now that physicist of the end of the 19th century were doing things that had no actual goal.
They weren't demanding billions of dollars of taxpayers money for their experiments.
A few dozens of billions is incredibely cheap given the life changing knowledge it will bring.
Such as?
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He saw something, obviously. He just wanted to see it more clearly.
But then she closed the curtains and he was stuck contemplating more distant heavenly bodies.
You need another one? So soon? (Score:5, Interesting)
You pesky physicists just keep running around in circles asking for more, MORE MORE money.. Is all this really necessary or are we really just funding a pile of PHD student's research?
So, why don't we just cut to the chase here and go with the biggest possible? I'm starting to get tired of this "We need a bigger one now!" thing.
Seriously, So now that they've managed to find the Higgs boson we are done with the LHC? I'm looking for a really good reason we need a bigger collider here and I'm not seeing any given. Is there some theory we need to test or some additional advances in technology which depend on a better understanding of subatomic physics at such large energies? I'm no physicist, but I'm not seeing a reason for this expense, other than having a new, bigger and more expensive shiny toy.
Help us out, what will 100 TeV get you that your 14 TeV won't?
Re:You need another one? So soon? (Score:4, Informative)
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That's until it's built and then we decide to use Saturn's ring as a basis for the next one, obviously.
Design study & font choices (Score:2)
Reading the design study by Peter Limon (http://vlhc.org/Limon_seminar.pdf), I couldn't help but notice that it made rather liberal use of Comic Sans.
I'll probably burn some of my karma to say this, but I must say it: Nothing screams professionalism like Comic Sans.
Crowd funding (Score:5, Funny)
They should kickstarter the money for it. I'll throw in $50. Flex goals: Stargate; flux capacitor; warp drive.
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Crowdfunding a $5 billion project, fifty bucks at a time, would require a third of the United States, or 3% of the entire planet.
It's like Horsepower and other things. (Score:2)
This is like the quest for horsepower. One guy gets a supercharger, the other gets twin turbos. One guy sees a car producing 1150 HP while his only produces 1100. Next thing you know he's ripping out parts just to get that little bit more. I think the scientists on the LHC are over-compensating, maybe we should just send them packages of Enzyte instead?
Particle Colliders in Space? (Score:2)
Could that be possible? To build a particle collider in the orbit (or at a Lagrange point). Focusing of the beam wouldn't be easy, but it would be certainly doable. I'm thinking a straight collider or a giant laser like setup. I wonder how protected the system should be of outside interference?
The cosmic rays themselves probably randomly collide too with each other and create exotic byproducts. I wonder what's the actual chance of a natural head-on collision...
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Ignoring the physics aspect of it... since I'm not qualified to even "guess" if there would be issues
I imagine the major issues would be:
- Price of construction
- Price of delivering construction pieces: it's like thousands and thousands of dollars to send up 1lb of stuff into orbit
- Space junk and asteroids - something the size of an eye-glass screw could pretty much ruin the whole thing. And there's a lot of crud in orbit
- You'd need people to maintain it, run it, etc. That's a large expense right there
helium? (Score:2)
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The helium at LHC is liquid helium used to cool the superconducting magnets, not to fill the tunnel.
But maybe by the time this is built we'll have room-temperature (or nearly so) superconductors that can sustain that kind of magnetic field. (AFAIK the LN2-cooled ceramic superconductors can't.)
LHC didn't make a black hole (Score:2)
Naming conventions for concentric circles (Score:4, Funny)
If the present one is the Large Hadron Collider, the next one the Very Large Hadron Collider, then the following one should be the Ultra Large Hadron Collider.
1. Large Hadron Collider
2. Very Large Hadron Collider
3. Ultra Large Hadron Collider
4. Extremely Large Hadron Collider
5. Gargantuan Large Hadron Collider
6. Mammoth Large Hadron Collider
7. Unbelievably Large Hadron Collider
8. Inconceivably Large Hadron Collider
9. Budget Busting Large Hadron Collider
After this, there won't be money left to build any more.
Each new larger collider should be constructed with it's center at the same center point as previous colliders. Thus all of the colliders form a set of concentric rings. They can be called the Nine Circles of Collision.
Just the bonus for a few sleazy bankers (Score:2)
When the LHC was first built I was impressed by the multi billion $USD cost. Now we spend that much just bailing out a bank so they can pay bonuses to their never-indicted criminal executives.
It's funny how we can't afford to repair our bridges and schools, but when it comes to bailouts and worthless wars, cost is no consideration.
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Road sign: No new particles, next trillion dollars (Score:2)
These physicists are going to have to wash a lot of dishes to get that puppy in their xmas stocking.
Looking for what? (Score:2)
Do we have some untested models or hypothesis that demand 100 TeV to verify? Otherwise, what are we building it for?
Back in my sciencey days, I was always taught that one had to have a question to be answered in mind before going off and designing cool experiments.
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They have to smuggle them in by labelling them as "jeebus detectors", "rapture attractors" and "age counter that only goes up to 6000".
Re:WHY NOT IN THE FIRST PLACE !! (Score:5, Informative)
Well, many of these tunnels, including the one the LHC uses, have been refurbished multiple times already. Cern's main ring was built to be somewhat future-proof, but that was a long time ago. A google search came up with The history of CERN [web.cern.ch], which dates the groundbreaking to 1954.
In accelerators you have two basic designs: linear and circular(ish). In linear accelerators each boosting element (RF cavity or whatnot) gets one chance to give the beam particles a kick, so the energy is limited to how hard you kick (limited by technology) and how many elements / how long (limited by budget).
In circular accelerators you are limited by synchrotron radiation. At some point the energy pumped into the beam matches the energy lost via synchrotron radiation. To move in a circle you have to accelerate inwardly, and an accelerating charged particle radiates light. At particle accelerator energies, this radiation is in the x-ray spectrum. You can reduce the loss by using a larger ring -- a smaller curvature requires less centripetal acceleration and hence less radiation loss. You can also of course build stronger boosting elements, but the radiation also heats the beamline and surrounding superconducting magnets, so it's not "that simple."
The other thing to vary is the kind of particle accelerated. Electrons have a very small mass and lose a larger fraction of their momentum to synchrotron radiation. SLAC and KEK are linear accelerators that use electrons. (Cornell's CESR is a ring that accelerates electrons too, but at lower energies compared to these others.) Protons are the other obvious choice, which is what Fermilab and CERN's LHC (after the upgrade) are accelerating. Being much more massive, the protons slough off less of their momentum to synchrotron radiation and can be accelerated to higher energies given the same size ring. The disadvantage of protons is that the energy of the proton is shared among its three quarks (and gluons I think) whereas the electron is truly singular as far as can be told.
I've been out of touch lately but as of at least 8 years ago three proposals were being discussed: VLHC -- big ring accelerating protons. Next Linear Collider (NLC) -- long linear accelerator for electrons. Muon collider -- a smaller ring (actually with straight sections like a track&field track) that produces and accelerates muons. Muons are just like electrons only 200 times more massive and is unstable with a half-life of 2 microseconds. The muon collider was thought to be an ideal Higgs factory, but with a lot of design challenges. One of the main challenges is to not only accelerate the muons before they decay, but also collimate, or "cool", the beam very fast as well so that you can create as many head-on collisions as possible.
So the news that the VLHC design is currently in favor is interesting, but this is hardly the first time the issue has been discussed and I doubt it will be the last. Several years ago the NLC design seemed most favorable, but this would, by its length, be limited to a specific design energy and probably be built to produce Higgs, Higgs, and more Higgs. It seems to me like a VLHC would have more discovery potential for more massive Higgs particles, signs of supersymmetry, or whatever else might exist.
Re:WHY NOT IN THE FIRST PLACE !! (Score:5, Interesting)
I also wanted to mention the failed SSC in Texas, cancelled in 1993. That would have been running at double the LHC's energy about a decade earlier. In 1993 congress seats were won by senators promising budget cuts, and Big Science had a large target painted on its back. Killing the SSC was a big-profile way of appearing to reduce spending while at the same time not damaging something that many people understood or cared about.
Since that time, the US has proved time and time again that they are incapable of sustaining funding for a long-term science project. All of the high-energy accelerators in the US are operationally shut down, and almost no proposals in the past 20 years or so have survived all the way to producing results before getting scrapped by some budget shortfall in a particular fiscal year. The LHC survives because the US is not such a major (or critical) contributor.
Re: (Score:2, Interesting)
Can you explain what the actual, tangible benefits of throwing billions and billions of dollars at the SSC would have been? Other than a demand from Big Science for even more money a few years later to build Even Bigger Science?
Re: (Score:3)
It difficult to predict the benefits of machines that were not built. From past machines, work on linear electron colliders like the SLAC SLC and the never built but lots of R&D TESLA, and NLC led to high brightness electron linacs. Those are now being used to drive X-ray free electron lasers (DESY:FLASH, SLAC:LCLS, Spring-8 SCCS, Trieste , etc).
Those X-ray lasers are now being used extensively for practical research: protein structure measurement, femtosecond chemistry, superconductivity research, m
Re: (Score:2)
These days the major ideas are:
ILC: A superconducting electron linac based collider. Significant chance the Japanese will host this - we'll know more in a year or so.
CLIC: A CERN design normal conducting 2-beam electron linac (x-band). Sort of a hybrid of the old SLAC X-band NLC concept and the old CLIC 30GHz 2-beam machine. Technically challenging (very tight alignment tolerances), but possible.
Muon collider: Fermilab and others. Very ambitious, completely new type of machine, very difficult.
Plasma accel