A Detailed Profile of the Hadron Super Collider

davco9200 writes "The New York Times has up a lengthy profile of the Large Hadron Collider. The article covers the basics (size = 17 miles, cost = 8 billion, energy consumption = 14 trillon electron volts) and history but also provides interesting interviews of the scientists who work with the facility every day. The piece also goes into some detail on the expected experiments. 'The physicists, wearing hardhats, kneepads and safety harnesses, are scrambling like Spiderman over this assembly, appropriately named Atlas, ducking under waterfalls of cables and tubes and crawling into hidden room-size cavities stuffed with electronics. They are getting ready to see the universe born again.' There are photos, video and a nifty interactive graphic."

Comments

Sexist/Agist

[Anonymous Coward]

From the article:

"the physics is complex, but the controls are so simple, even my grandmother could use it."

As a 48 yo grandmother, I am offended that technical incompetance is equated with being a grandparent. I don't think anyone would have said "so simple even my grandfather could implement."

I am incidentally, a C programmer of 20+ years.

Re:Sexist/Agist

[andy666]

I have to say, that while I respect that you are an experienced IT person, I think you are being a bit too sensitive here. Indeed, most people's grandparents do have trouble with technology. I don't have a reference for you, so that's anecdotal, but I think most people will agree with me.

Re:Sexist/Agist

[Anonymous Coward]

Damn lady, you've been 48yo for years now!

> As a 48 yo grandmother, I am offended that technical incompetance is equated with being a grandparent. I don't think anyone would have said "so simple even my grandfather could implement."

That's because males often are genetically enhanced cyborgs.

Re:Sexist/Agist

[douglips]

Do you think the person quoted is 4 years old like your grandchild? Or maybe he/she is 35-34, and his grandfather is dead.

Sometimes a cigar is just a cigar.

Re:Sexist/Agist

[u-bend]

Furthermore: 1. It says "my" grandmother. I could see it being offensive, if it caught you on a bad day, if it said "your" grandmother. 2. Where did you read that? I've searched all six pages of the article and couldn't find your phrase. 3. Are you kidding/trolling?

Re:Sexist/Agist

[Anonymous Coward]

Well, they can't very well say "it's so easy a caveman could do it", now can they?

Re:Sexist/Agist

[Moofie]

Did you know that the author's grandmother and you are not the same person, and might have different capabilities?

Re:Sexist/Agist

[Anonymous Coward]

and sometimes it is a penis

Re:Sexist/Agist

[chribo]

The quoto from the article is definitly wrong. Should be:
"the physics is complex, but the controls are so simple, even a theoretical physicist can use it." ;)
- chribo

Re:Sexist/Agist

[Anonymous Coward]

"the physics is complex, but the controls are so simple, even my grandmother could use it."

As a 48 yo grandmother, I am offended that technical incompetance is equated with being a grandparent. I don't think anyone would have said "so simple even my grandfather could implement."

I am incidentally, a C programmer of 20+ years.

The keyword is my grandmother and NOT your

Aside from that, so what? Just because you are the exception to the rule doesnt invalidate the stereotype. If a person jumps off a 14 story building and survives, does that mean eveyone that does it will also?

Re:Sexist/Agist

[Anonymous Coward]

so simple, even my grandmother could use it.

So who will be having the roast duck, with the mango salsa?

Re:Sexist/Agist

[Oink]

I don't know if that's the inside joke I think it is, but I think you're way off base. The theoretical physicists we've had briefly in our lab (for requisite graduate student lab experience) couldn't handle anything more complicated than a pencil! One of them used a gallon jug of acetone to clean something the size of a quarter (exaggerating, but only slightly.)

Re:Sexist/Agist

[Anonymous Coward]

Because theoretical physicists are what? Smart?!

Hmph.

Re:Sexist/Agist

[WilliamSChips]

Could they say "It's so easy a therapist could do it"?

Re:Sexist/Agist

[Anonymous Coward]

3: Yes.

Re:Sexist/Agist

[Loconut1389]

Yes, I'll take The Rapists for 20.

Re:Sexist/Agist

[azenpunk]

they should have gone with "even a caveman can use it", get some free publicity runoff from geicko.

Cool

[grub]

They are getting ready to see the universe born again.

It's like having a Tivo with a 6,000 year replay capacity!

Re:Cool

[sentientbeing]

Theyre stating the obvious about the daily workwear though, I thought.
 
- When youre creating a captive mini black hole on Earth I would have thought hard hats and steel toecapped boots would be a MINIMUM safety requirement.

Re:Cool

[CelticWhisper]

WHOOOOOOOOOOOOOOOOOOSH...

Re:Cool

[javaxjb]

Just in time for a born again Christian to be reincarnated in a born again universe?

Re:Cool

[grub]

Yeah, I heard that Jerry Falwell died today. I guess he wasn't sucking Jesus' cock hard enough.

Re:Cool

[Cervantes]

It's like having a Tivo with a 6,000 year replay capacity! Great! That'll be JUST enough time for the writers of Lost to figure out a coherent plot line!

Re:Cool

[quitcherbitchen]

It's one step closer to square one:
http://pbfcomics.com/?cid=PBF032AD-Reset.jpg#102

Re:Cool

[markov_chain]

I think you're on to something, they are even measuring their data storage in units of Bible (Old and New Testament):*

The ATLAS computing system will be designed to analyse the data produced by the ATLAS detectors. The amount of data will be huge. To get a feeling, note that the English version of the Bible (Old and New Testament) can be stored on a floppy disk of 1.4 Megabytes. The annual ATLAS data volume would need 700 million such disks.

* OK, it's a stretch, but it's all in good fun.

Re:Cool

[weg]

Well, it seemed to me that at least some Americans are working there? ;-)

Re:Cool

[malsdavis]

No it won't. They'll still just make it up as they go along and deny the previous episodes ever happened.
Audience: what happened to the dinosaur? writers: what dinosaur?
Audience: what happened to the polar bears? writers: what polar bears?
Writers: Lalalalalalaalal, we can't hear you.

Re:Cool

[Anonymous Coward]

I don't a unit of energy is measured in volts...

Re:Cool

[Enlightenment]

It's not. It's measured in electron volts. 1 electron volt is equal to the charge on an electron (absolute value) times 1 volt. A volt is a unit of energy per unit charge, so (Energy/Charge)*Charge = Energy. Or if you want to know it in joules, 1 Volt = 1 Joule/Coulomb and the charge on an electron is 1.60*10^-19 Coulombs, so 1 eV = 1.60*10^-19 Joules. So that means they're measuring mass in terms of energy--which is fine, if you remember your Einstein.

Re:Cool

[Anonymous Coward]

Woosh.. like the sound of something flying by without hitting you? What a great analogy. Man, that's even more clever than this!!!

Re:Cool

[Thing 1]

[...] remember your Einstein.

There are two books of his freely downloadable from Project Gutenberg:

Relativity : the Special and General Theory

Sidelights on Relativity

I've read the former. Amazingly insightful, and approachable as well. The two examples stick with you: on a train traveling next to a platform, drop a stone and observe from a point on the train versus a point on the platform; and a man in outer space, in an opaque cubic box with a string attached to one surface; if someone pulls it at 9.8 m/(s*s), then the man experiences exactly what he would experience if the box were on the surface of the Earth. (Special and General, respectively.)

Compact?!

[TheWoozle]

"Above is one of the collider's massive particle detectors, called the Compact Muon Solenoid"

I'd hate to see the Large Muon Solenoid!

Re:Compact?!

[perturbed1]

Yeah. That's called ATLAS. Except it has a toroid as well as a solenoid technically...

Re:Compact?!

[l0b0]

It's pretty compact compared to the size: 12,500 tons in a cylinder 21.6 meters long and 15 meters in diameter.

<shameless_plug>Oh, and they do have retina scanners and other outlandish technology!</shameless_plug>

Thank goodness there's no typo

[Nimey]

I don't even want to think about a hardon supercollider.

Re:Thank goodness there's no typo

[Anonymous Coward]

For a minute, I thought "Hardon Super Collider" was the name of the Japanese version of "America's Funniest Home Videos".

Re:Thank goodness there's no typo

[CaptainPatent]

It would be twice the size, but instead of an electrical input it would run off of 15 million Viagra!

Re:Thank goodness there's no typo

[4D6963]

I don't even want to think about a hardon supercollider.

*phew* Thank you! Only came here for the hardon jokes, and for a minute I feared I wouldn't see any.

Re:Thank goodness there's no typo

[WilliamSChips]

I get a hadron just thinking about the supercollider!

Re:Thank goodness there's no typo

[Anonymous Coward]

That's why the need the kneepads

Cue the hardon collision jokes

[spun]

Actually, don't.

Re:Cue the hardon collision jokes

[Anonymous Coward]

too late

Life sucks

[nih]

when the universe starts again my life better not suck as bad as it has, or i want my money back!

Re:Life sucks

[Anonymous Coward]

don't worry you'll be reborn as a snail

what a disapointment...

[excelsior_gr]

...I initially read "A Detailed Profile of the Hardon Super Collider".

The Problem with Something this Expensive

[Nom du Keyboard]

The problem with something this expensive is that the average person, including myself, cannot see, even if it provides every answer they hope for it, how that will change my everyday life in the least. At least the Space Program gave us Tang.

Re:The Problem with Something this Expensive

[Jamu]

The expense of Physics isn't a problem until it's unaffordable. Physics has always been profitable in the long term, and survives because it's profitable in the short term. And Physics gave you the Space Program.

Re:The Problem with Something this Expensive

[qc_dk]

Well, you used something that came from the CERN collaboration to write your question. I would say that WWW has certainly changed the daily life of almost all of us, and the economic boom that it caused through the 90s has certainly been a bountiful repayment of our investment.

Cheers,
Qc_dk
Ps. I used to work at cern and with the 10'000 men and 2 women there, there certainly was a lot of large hardon collisions. I believe you USians call it cockblocking. ;)

Re:The Problem with Something this Expensive

[Loki_1929]

Pure science has no marketable goals in mind. What will the discovery of new particles bring to the world? No one knows, just as no one knew the consequences of the discovery of the electron in 1897. Yet we now have a world where the bulk of the economy is built upon knowing its properties and behavior. Pure science brings about quiet revolutions in unpredictable ways, and those who recognize that realize that funding it is vital to progress. You mention the space program giving us Tang; have you any idea how many commercial products have come about as a direct result of the space program? Any idea of the lives saved and the progress achieved through the struggles brought about by our venturing into space?

Re:The Problem with Something this Expensive

[wanerious]

I'm not trying to be offensive, but that sounds like a remarkably egotistic statement. Should it be required to change your life in any way for you to care about it? Rather than something being wrong with the experiment in that it has no intersection with your interests, perhaps the problem is that your interests are too narrow to accommodate something that (I'd argue) is objectively interesting by any measure. Here is an opportunity for the average person to learn something about the fundamental nature of the Universe to understand the results.

Re:The Problem with Something this Expensive

[Anonymous Coward]

While it's true that HTML came out of CERN, it was hardly the direct result of their work. It was just a useful way to share information. Because of that, something basically like HTML was bound to crop up somewhere in short order (and in fact, similar markup languages did), regardless of how many MeV the blokes at CERN were smashing things together at. Of course, other advances important to the WWW were driven by the large amounts of data produced by these physics labs, but the case remains that this was merely to support the physics research, not a direct result of it.

Not to knock CERN or other labs. If nothing else, the intellectual stimulation of learning how the universe works is worth at least as much as paying philosophy professors at public universities to continually re-ask the same questions the Greeks were.

Re:The Problem with Something this Expensive

[timeOday]

Should it be required to change your life in any way for you to care about it?

Did you really mean "care about," or "pay for?"

Re:The Problem with Something this Expensive

[Moisteri]

It could create a disturbance in space/time continuum and open up a rift on your backyard. Handy for dumbing garbage into.

Re:The Problem with Something this Expensive

[wanerious]

Either one. Members of a society should occasionally pay for things that are not in their self-interest. This, in my opinion, is surely in that category. It is so interesting that, also in my opinion, every member of the society should attempt to appreciate the science.

Re:The Problem with Something this Expensive

[Somnus]

To me endeavors like this are the most perfect expression of man. Vonnegut wrote in Breakfast of Champions,

Our awareness is all that is alive and maybe sacred in any of us. Everything else about us is dead machinery.

To plunge into the unknown is a moral imperative for any thinking being.

If all you care about are material practicalities, this thing is roughly 1/50th the current cost of a certain misadventure in the Middle East, and is more likely to produce cool stuff. One particularly exciting bit of technology already is the LHC's grid computing infrastructure.

Re:The Problem with Something this Expensive

[Nom du Keyboard]

Should it be required to change your life in any way for you to care about it?

When I'm paying for it -- Yes!

What I'm saying is that this is far more money than I'll ever see in this lifetime, for something that doesn't appear likely to improve my life one iota in the process. I'm stating a common point of view for many people about projects like this, which is not egotistic at all.

Re:The Problem with Something this Expensive

[kindbud]

"At least the space program gave us Tang. At least the space program gave us Tang." And I suppose that computer you're using is made of stone knives and bear skins? Open your eyes man! Especially if you've had LASIK surgery to correct nearsightedness. Neither computers nor the internet nor the delicate molecular manipulations of the cornea - made with lasers that are also guided by computers - would be possible without the insights gained from the kind of experiments that the LHC enable. And that's just what I can think of in the two seconds it takes to formulate a /. reply.

Re:The Problem with Something this Expensive

[wanerious]

Just because the opinion is popular doesn't make it right. It is certainly egotistic to assume that the project should not be funded just because it doesn't affect your life. It may well affect others. The implicit assumption is that your life and interests are complete and in the right; whereas I would argue that the cause is right, and something about you might be broken if you can't see the worthiness of it. One aspect of maturity is the ability to sacrifice for the benefit of others.

Re:The Problem with Something this Expensive

[mines_bigger]

U do state arguments like that when it comes to war machinery, do you ? (Got a gun at home ?)

Re:The Problem with Something this Expensive

[Ambitwistor]

The Large Hadron Collider likely will not change your everyday life, unless you're really into physics. It's not supposed to. It's supposed to help the human race learn more about the natural world in which we live.

Senator John Pastore: Is there anything connected with the hopes of this accelerator that in any way involves the security of the country?

Robert Wilson: No sir, I don't believe so.

Pastore: Nothing at all?

Wilson: Nothing at all.

Pastore: It has no value in that respect?

Wilson: It has only to do with the respect with which we regard one another, the dignity of men, our love of culture. It has to do with: Are
we good painters, good sculptors, great poets? I mean all the things we really venerate in our country and are patriotic about. It has nothing to do directly with defending our country except to make it worth defending.

— at the Congressional Joint Committee on Atomic Energy, April 17, 1969, regarding the justification for funding the then-unbuilt Fermilab National Accelerator Laboratory

Re:The Problem with Something this Expensive

[Anonymous Coward]

for me, it's good enough that the biggest machine on earth does not work for either the military or some corporation, but for the whole of mankind, for future generations and for all of us. that's a very nice thought, i think.

Re:The Problem with Something this Expensive

[Dirtside]

Tang was created in 1957 or so, and had nothing to do with the space program until they started using it during Gemini.

That aside, the answer to your question is that we don't know what we're going to learn from projects like this. But we do fundamental research like this anyway, for a variety of reasons best expressed by this article.

Re:The Problem with Something this Expensive

[Lord Ender]

You got tang out of the space program? I haven't even had a date since before Sputnik :-(

Re:The Problem with Something this Expensive

[frisket]

Yep. And the documentation at CERN is done using TeX :-)

Re:The Problem with Something this Expensive

[Tempest451]

The first thing I could think of is Warp Drive. But thats me.

Re:The Problem with Something this Expensive

[Anonymous Coward]

How I wish I could mod up parent!

Re:The Problem with Something this Expensive

[brice_c]

Actually, a lot of new technologies that have immediate applications in your daily life had to be invented.
For instance, the CERN Openlab http://proj-openlab-datagrid-public.web.cern.ch/pr oj-openlab-datagrid-public/ develops new networking, storage and parallel computing technologies that will help us deal with the incredible quantity of data that will be generated by the LHC experiments.
Along the same line, new tomographic methods will revolutionize the way we treat cancers and leverage medical imagery. http://bulletin.cern.ch/fre/articles.php?bullno=04 /2005&base=tra

So no, it's true, if you're part of a CERN member state, it wasn't what you paid for with your hard earned tax money. It's like a big chocolate box, it's be a shame to throw it all away just because you don't like almonds right ?

Re:The Problem with Something this Expensive

[ilzogoiby]

> Yep. And the documentation at CERN is done using TeX :-) http://twiki.cern.ch/ Doesn't look like TeX ;)...

Re:The Problem with Something this Expensive

[tenco]

The problem is (from my point of view, of course :), that normal people just think different.

Re:Cue "Large Hardon" jokes

[Sherloqq]

Heh, I'm glad I'm not the only one with a mind experiencing Freudian slips...

"Energy Consumption" - WTF?

[NewbieProgrammerMan]

...energy consumption = 14 trillon electron volts...

So that means the LHC only uses 2.24 microjoules? Is that per second or per fortnight?

Re:"Energy Consumption" - WTF?

[Bazman]

That's more like 'per hadron'. Ask your electricity supplier to bill you per hadron...

Re:"Energy Consumption" - WTF?

[phaunt]

From TFA:

Everything about the collider sounds, well, large -- from the 14 trillion electron volts of energy with which it will smash together protons (...)

So that energy is not the consumption (which would be more usefully measured in Watts anyway, as you point out), but the energy the particles have when they collide (which is usually measured in (T)eV).

Re:"Energy Consumption" - WTF?

[rhombic]

Ask your electricity supplier to bill you per hadron...

Particularly since electricity suppliers only provide you with leptons, no hadrons. And they make you give them back when you're done with them. Bastards.

Re:"Energy Consumption" - WTF?

[Jamu]

Or to put it another way: the LHC is not 100% efficient and can't be powered with a single postgrad and a bicycle generator. The true power consumption of the LHC will be about 120 MW.

Re:"Energy Consumption" - WTF?

[Mr2cents]

Hmm.. I thought that each proton would be accelerated to 7 TeV, so when they collide there is a 14 TeV collision. In any case, "energy consumption" is the wrong term.

Re:"Energy Consumption" - WTF?

[anzev]

This really is a strange figure. It might reference anything but the consumption, most notably, the "energy" inside the ring. Or maybe the consumption of ONLY the ring itself, becaue when you start looking at the magnets, and vacuum pumps, and control system infrastructure you quickly find out that you need to be connected to at least 2 power grids :-). At least that's the case with DESY if I remember correctly.

Re:"Energy Consumption" - WTF?

[Anonymous Coward]

Thank goodness they take your old leptons back. Housekeeping is bad enough without having to figure out how to dispose of al those leptons.

Re:"Energy Consumption" - WTF?

[jimbo3123]

Yeah, that 14 TeV has to be the energy of the particles, not the entire consumption of the machine.

BTW, the energy consumption of the machine would never be measured in Watts (the SI unit of POWER). It may be listed in kw-hr though.

My TI-85 tells me that 14 Tev is about .623 pico kw-hr (6.23 x 10^-13).

Re:"Energy Consumption" - WTF?

[phaunt]

BTW, the energy consumption of the machine would never be measured in Watts (the SI unit of POWER). It may be listed in kw-hr though.

Well, you were only told "the machine consumes n kWh", you wouldn't be a lot the wiser. If you were told it consumes n kWh in m hours of operation, you'd be back at power (to wit n/m kW). Energy consumption for household appliances is also listed in kW.

Re:"Energy Consumption" - WTF?

[Luyseyal]

Hey this isn't ITER! :)
-l

Re:"Energy Consumption" - WTF?

[Muad'Dave]

Rodents Of Unusual Size? I don't think they exist.

Rodents Of Unusual Size definitely exist.

They're even classified as fish (according to the Catholic Church), and can be eaten on Friday!

Re:"Energy Consumption" - WTF?

[Clandestine_Blaze]

That's more like 'per hadron'. Ask your electricity supplier to bill you per hadron... If I did that, I would be really broke!! Oh wait, you said hadron. Nevermind.

Re:"Energy Consumption" - WTF?

[FuzzyDaddy]

Particularly since electricity suppliers only provide you with leptons,

Your utilities do that?? My sneaky bastards make me give one back for every one they give me... and every 1/120th of a second, they sell me the same one they just sold me!

Re:"Energy Consumption" - WTF?

[Rich0]

I hate to be pedantic, but I think a given electron crosses the property line in your direction once every cycle - not half-cycle.

Let's start a zero voltage with the electron right on the border of your property. The voltage rises to 110/220, and the electron moves towards your house and you "buy" it. Voltage drops to zero and it comes to a halt inside your house somewhere. Voltage drops to -110/220 and the electron moves away from your house. Voltage rises to zero just as the electron crosses your property line and is "returned" to the utility. Thus completes one cycle.

The same logic applies wherever the electron starts out.

Re:"Energy Consumption" - WTF?

[P3NIS_CLEAVER]

Mine bills in tachyons, they are charging me for energy I haven't used yet!

Re:"Energy Consumption" - WTF?

[cyberanth]

It means the particles in the collider are accelerated up to 14TeV; energy is the relevant parameter in high energy physics, strangely enough. If the Higgs weighs 140 GeV for instance, we need to accelerate particles in the collider to more than that energy to produce one.

Re:"Energy Consumption" - WTF?

[Anonymous Coward]

My TI85+1 tells me that looks a lot like Avogadro's number...

Re:"Energy Consumption" - WTF?

[FuzzyDaddy]

T = 0 : electron goes out
T = 1/120th: electron comes in
T = 1/60th: electron goes out again

So yes, it comes in once every 1/60th of a second, but the time between leaving and coming back again is a half cycle.

Re:"Energy Consumption" - WTF?

[FuzzyDaddy]

Of course, if you wanted to be REALLY pedantic, you'd point out how electrons are indistinguishable, and the fermi velocity is much higher than the drift velocity, and the whole process is statisitical...

OK, the jokes REALLY dead now.

Re:"Energy Consumption" - WTF?

[Xiaran]

The joke is dead but when I was in university an electronics lecturer told me a story about a guy in the UK who had bypassed his electricity meter to avoid paying the bill. The company soon found out what he was doing and told him to stop doing it or they would take him to court for damaging their property. He kept doing it and they took him to court over theft apparently. He tried to make the claim in court that he had stolen nothing because every electron the company had provided him with he quickly returned so there was of course no theft. He of course lost... but I always wanted to meet that guy :)

Re:"Energy Consumption" - WTF?

[FluxIntegrator]

When did the joke become more important than the science on Slashdot? Where did all the nerds go?

17 miles.

[foodnugget]

seventeen miles? I went to look at the pictures, but i don't see anything that comes close to seventeen miles. Certainly, i don't doubt it, but not knowing much about particle accelerators and supercolliders, i am very curious to get the big picture. If something is seven-teen-miles long, or around, or deep or high, wow, do i really want to see it. or an overlay of it on a map if it is underground!

Perhaps it is just the structural engineer side of me, but i would love to know more about how they made something that large.

Re:17 miles.

[fred ugly]

check the nifty interactive graphic!

Re:17 miles.

[Silver Sloth]

As ever you can start with Wikipedia and work outward from there.

Re:17 miles.

[brunascle]

das ist underground.

Re:17 miles.

[Anonymous Coward]

It doesn't work and I don't see any "missing plugin" warning.

Re:17 miles.

[UnHolier than ever]

The ring is 17 miles. There are four detectors at different points on that ring, each of which is of course much smaller. The photos in the article show the detectors.

Re:17 miles.

[DerekLyons]

There's this neat tool called Google...

Re:17 miles.

[Anonymous Coward]

it's not that hard, you just have to dig a hole that is 1 mile long, 16.8 times, and then connect them all end to end! ;-)

We don't need no stinkin' Higgs

[sweetser]

Sorry Charlie, the animations of the Standard Model are up on YouTube, http://youtube.com/watch?v=ExNPiMcVXww

U(1) is a unit circle in the complex plane. SU(2) is a unit quaternion which is easy to animate if you have software for the job (barf out thousands of exp(q-q*), sort by time, drive through POVRay). Electroweak is the product of the first two. The animation of SU(3) tells you what the standard model is about, namely the ability to smoothly describe any event seen by an observer at 0,0,0,0. Gravity is about the sizes of things, so scale the ball to different sizes in a smooth way, and that is the symmetry behind gravity.

It is inertial mass that breaks the symmetry of standard model, not some phony Mexican hat dance around a false god of a vacuum.

doug

Re:We don't need no stinkin' Higgs

[Somnus]

Questions:

* What does the quarternion formulation tell us that the standard Standard Model formulation does not? I understand that it provides a unified framework for treating the different groups, but particles in the Standard Model are still charged separately under electroweak and strong -- is this a high energy theory, where we expect gauge coupling unification somewhere?

* I don't understand your concept of inertial mass breaking gauge symmetries. The Standard Model is Lorentz invariant, and gauge particles have to be massless to preserve gauge invariance. A Higgs condensate breaks the SU(2) gauge symmetry by making the gauge fields massive. How does your idea work?

Re:We don't need no stinkin' Higgs

[sweetser]

On point of contention is EM tensor_product Weak tensor_product Strong. That leads to a nice, neat, 12 degrees of freedom. That also reflects the history of particle physics, where we learned about EM first, then the weak force in the 1930s, then then eight-fold way in the 1960s. Things is, U(1), SU(2), and U(1)xSU(2) are subgroups of SU(3). I didn't read that, I saw it, and that was confirmed by talking with a math guy from Mathematica at an APS meeting. I think the standard model should more tightly reflect what goes on with the math, not the history of our discoveries in particle physics. I know this makes EM and the weak force feel "too close" to the strong force, but the math side of my brain says too bad, that's the way it goes. This is not a high energy theory. It is an odd assault on the second x of U(1)xSU(2)xSU(3).

> * I don't understand your concept of inertial mass breaking gauge symmetries.

Great question. The Standard Model is only about EM, the weak and the strong forces. The Higgs is there to bring in inertial mass. And gravity as everyone knows, doesn't get invited to the party. We all know that is wrong. We need gravity right there. The graviton also must be gauge invariant to travel at the speed of light. So do I want it both ways? Of course I do!

Here's how it is done. Use an asymmetric tensor, d^u A^v. This tensor is reducible, so it cannot represent fundamental forces. Cleave it in 2, to an antisymmetric tensor, d^u A^v - d^v A^u, to do the work of EM with a spin 1 field, and a symmetric tensor d^u A^v + d^v A^u to do the work of gravity with a spin 2 field. The antisymmetric tensor will always be gauge invariant, cruising at the speed of light. The symmetric tensor will also be gauge invariant if and only if the trace happens to be zero. This is the house where the graviton lives. The graviton does the work of gravitational mass. When the trace is not zero, that breaks the gauge invariance of the model. The trace of d^u A^v + d^v A^u is a scalar field that does the job the Higgs is suppose to do. The job is done better because now there is a particle explanation of the equivalence principle: tr(d^u A^v) = 0 is for the graviton and gravitational physics, and tr(d^u A^v != 0) is for the scalar field needed for interial mass.

I'll ramble to anyone over a beer. I bought an IPod just to demo these animations :-)

doug

Re:We don't need no stinkin' Higgs

[Anonymous Coward]

I was under the impression that any graviton-as-spin-2-fields theory was non-renormalizable due to graviton-graviton interactions. While I haven't really grasped what you've described (do you have any papers on Arxiv or elsewhere that I can read?), what features of this theory change that original problem?

Re:We don't need no stinkin' Higgs

[Somnus]

* A total SU(3) is a neat idea, but how does it jibe with experimental data? Given the difficulties with technicolor, my guess is that it doesn't.

* Gravitons are spin 2, but it's not true that spin 2 particles are gravitons. Can you identify your rank-2 symmetry generators with the Lorentz group? Finally, is it renormalizable?

Re:We don't need no stinkin' Higgs

[khallow]

On point of contention is EM tensor_product Weak tensor_product Strong. That leads to a nice, neat, 12 degrees of freedom. That also reflects the history of particle physics, where we learned about EM first, then the weak force in the 1930s, then then eight-fold way in the 1960s. Things is, U(1), SU(2), and U(1)xSU(2) are subgroups of SU(3). I didn't read that, I saw it, and that was confirmed by talking with a math guy from Mathematica at an APS meeting. I think the standard model should more tightly reflect what goes on with the math, not the history of our discoveries in particle physics. I know this makes EM and the weak force feel "too close" to the strong force, but the math side of my brain says too bad, that's the way it goes. This is not a high energy theory. It is an odd assault on the second x of U(1)xSU(2)xSU(3).

What's the contention here? The U(1) tensor SU(2) tensor SU(3) gauge is known and has been confirmed via particle classification. What's currently unknown is whether the gauge group is somewhat larger. For example, SU(5) or SU(3) tensor SU(3). It can't be too big without having more forces than the four known ones.

Re:We don't need no stinkin' Higgs

[sweetser]

Your impression sounds correct to me. The vacuum field equations I use are linear, and NOT a linear approximation of GR. Instead of binding gravity to the second rand field strength tensor T^uv, the coupling is between a 4-potential and the 4-momentum density. The difference between these two is not big. The only difference is that gravity fields are not sources. This is consistent with EM, were EM fields are not sources. Consistency is good.

The trick here is to be like EM when necessary, and different where necessary. There are no photon-photon interactions (unless things get odd), and likewise, there are no graviton-graviton interactions. That does not prove they theory is renormalizable. I don't have the skills to prove or disprove that point. I am hopeful, because it is basically the manifestly Lorentz invariant quantization of a 4D wave, but with 2 spin fields, a spin 1 for EM, a spin 2 for gravity. In text books, two of the modes of emission for the manifestly Lorentz invariant quantization of a 4D wave have to be made virtual. I put those virtual modes to work.

I am not a professional, so cannot post to Arxiv. I consider this paper a draft since it has not been read and reviewed by anyone with real qualification. http://www.theworld.com/~sweetser/quaternions/ps/e m2gem.pdf

doug

Re:We don't need no stinkin' Higgs

[sweetser]

You are correct that people have tried to make bigger gauge groups. So far that has not worked. I am trying to make things smaller. We know there is EM and its symmetry is U(1). We know there is the weak force and its symmetry is SU(2). We know there is the strong force and its symmetry is SU(3).

With programs, the problems often appear at the interfaces. The tensor product of these three groups is presented as simple. Yet it means that you have to add a special flag onto both the groups U(1) and SU(2). The reason is that they are subgroups of SU(3), so any element of U(1) times SU(3) will be in SU(3). Identical particles don't like labels.

The animations are a visual justification of the 4 known forces in a smaller group, so I am in conflict with current research. Oh well.

doug

Re:We don't need no stinkin' Higgs

[sweetser]

The short answer: Jesus, those are tough technical questions that I don't have the answer to.

The creation and annihilation operators are in your quantum field theory book, in the section on Lorentz invariant quantization of a 4D wave. I was unable to understand how to write a spin 2 propagator (I gave some papers from Wienberg in the 1960s to a Ph.D. physics friend of mine, and he also did not figure it out).

I do know that the force equations that arise by varying the action with respect to the 4-velocity have like charges attract. I do know that the field equations that arise by varying the action with respect to the 4-potential have like charges attract. I do know the particles travel at the speed of light c if the trace of the field strength tensor is zero.

> Can you identify your rank-2 symmetry generators with the Lorentz group

I don't know why this has to be done.

doug

Re:We don't need no stinkin' Higgs

[Somnus]

Naively, if you want to write gravity as a gauge theory, you take the weak field limit and quantize the linear perturbation on a flat Lorentzian background. The linear perturbation has a local gauge freedom with Lorentz symmetry (flat Minkowski space has a global Lorentz symmetry).

So, if your gravity looks anything like general relativity, it should exhibit this property.

Anyway, these are indeed technical points that I was curious about -- thanks for fielding my questions.

Re:We don't need no stinkin' Higgs

[sweetser]

Thanks for this explanation, I think I get your point.

There is a way this proposal uses the word "gauge" in a different way than is usually done. Gauge means to measure. What is normally meant by this is you can add in a gauge field and it won't change a darn thing. EM is a gauge field theory, as is GR.

I want to use gauge to mean how a measurement is made, with the choice being how the spacetime manifold changes (the connection) or how a 4-potential changes or any combination of the two. So I could decide to work in a completely flat spacetime and do all the work with a 4-potential. Or I could decide to work with a boring (constant) 4-potential, and have the manifold bend as need be. I am making a choice on how the measurement is being made. No field is being added in. I can choose to do a mix and match, using a Newtonian potential to get the g_00 part right, and a dynamic metric with the g_11 a bit bigger than one so the light bending around the Sun works with this combo meal.

Talking with folks schooled in GR, I emphasize the case where the 4-potential is there in spirit, not in the calculation. I solve a differential equation, and out pops an exponential metric:

dtau^2 = exp(2(G^(1/2)q - GM)/c^2R) dt^2 - exp(2(G^(1/2)q + 2GM)/c^2R) (dx^2 + dy^2 +dz^2)/c^2

I almost never write the G^(1/2)q part because unified field theory is not a good thing to claim to do. So for an electrically neutral system, it is zero.

Now to your point, this could be approximated using the Taylor series like so:

    dt^2 = dt^2 - (dx^2 + dy^2 +dz^2)/c^2 - (2 GM/c^2R + O(2)) dt^2 - (2 GM/c^2R + O(2))(dx^2 + dy^2 +dz^2)/c^2

This has the local Lorentz symmetry, and a first order perturbation. Cool. I've known that for a long time, but this is a different way to think about it. Exponentials are very math friendly, so in my case it probably would not help in a calculation. It does connect to what other people do with gravity proposals.

Thanks,
doug

Re:We don't need no stinkin' Higgs

[khallow]

My point is that it can't be made smaller. If the EM gauge, U(1) were, for example, somehow embedded in the gauge for the strong force, SU(3), then electric charge would be easily violated by some strong force interaction (at least at sufficiently high energies assuming there's a symmetry breaking). We probably shouldn't see discrete electric charges under such a scenario. And keep in mind that there's more than one way you can get U(1) symmetries out of SU(3). There are some issues (like symmetry breaking and CP-violation) that confuse things, but I think it's been well-established that these three gauge symmetries aren't nestled in one another.

Re:We don't need no stinkin' Higgs

[sweetser]

Your position is both widely accepted and reasonable. Mathematically, it is clear that U(1) and SU(2) are subgroups of SU(3). The way I showed this was by the programming in the animation. To make U(1), I took a thousand quaternions at random, calculated q/|q|, and plotted that. To calculate SU(2), a thousand random quaternions were fed into exp(q-q*). To generate electroweak symmetry, U(1)xSU(2), these two were the products of each other: q/|q| exp(q-q*).

Up to this point, I am playing by the book, and have no disagreements.

Now I try to represent SU(3). Sounds like it might require two independent quaternions. Multiplying two randomly assigned quaternions together will not generate a new group, it will generate another member of the group q/|q| exp(q-q*).

Instead of multiplying the two together, I first took the conjugate of one, and then formed the product:

    (q/|q| exp(q-q*))* q'/|q'| exp(q'-q'*)

A question I don't know how to answer is how to write this. At first I made a silly mistake, and jotted down U(1)xSU(2)xSU(3). That has 12 elements of its Lie algebra, and I only used 8. In terms of the calculation, I know I calculated q/|q| exp(q-q*) twice for two randomly select quaternions, about 12,000 times for the youtube animation.

> electric charge would be easily violated by some strong force interaction

If true, the proposal would be wrong. Working with the nuts and bolts as I do, I see no reason why the q/|q| - the basic symmetry of EM and thus charge conservation - are in any danger by taking a conjugate and forming a product with another.

> We probably shouldn't see discrete electric charges under such a scenario.

If true, the proposal would be wrong. Again, I see no reason to suspect this will be the case. I can see the U(1) symmetry doing its thing whether inside SU(3) or not.

As I understand it, chromodynamics is such that it is nearly impossible to calculate anything. I doubt I'll ever understand any of that work. This definitely feels like it is a new direction, so there is hope.

I most like the "ontology", a fancy word for "why". There is no reason why these three groups of all the possible ones out there should be relevant to three of the four forces of nature. Nor is there any idea of how to bring in the forth. The animations give a visual explanation: to be able to describe any possible event in a smooth, continuous way from an observer at 0, 0, 0, 0 one needs the symmetries U(1)xSU(2) times the conjugate of another U(1)xSU(2). Make the ball a different size if you want to include gravity. A simple and visual explanation.

I respect your critique that much more needs to be done to make the case persuasive, but at least I can carry my work around on my ipod and show it to friends, and advancement of a sort.

doug

Re:We don't need no stinkin' Higgs

[khallow]

Hmmm, I need to correct my statements somewhat. I'm pretty sure the U(1) tensor SU(2) tensor SU(3) gauge has been observed (though I couldn't find a reference in my Review of Particle Physicsc handbook). But I was partly in error. If the above is a subgroup of SU(5) or SU(3) tensor SU(3), then there is some sort of symmetry breaking occuring to get the apparently gauge group above.

Re:We don't need no stinkin' Higgs

[sweetser]

I agree, any time the group is "bigger" in some sense, there must be a symmetry breaking to get things down to the observed level.

We have observed photon and the three particles of the weak force. The gluons are massless mediators of force between quarks. We have never seen quarks in isolation. I don't think we have ever been able to form a beam of gluons due to quark confinement.

I am claiming something like

    SU(3) = (U(1) tensor SU(2))conjugate tensor (U(1) tensor SU(2))

At this time I don't know what all the consequences of that happen to be. I'd love to speculate about other mysteries this proposal my address. I will refrain and keep my eye on what it does, which is give a visual justification for why there are three, and these three in particular, if one wants to develop a complete and smooth collection of any event that an observer at 0,0,0,0 happens to see.

doug

Born again...

[6Yankee]

They are getting ready to see the universe born again.

Great... So the next time I get stuck behind it in traffic I'm gonna have to stare at some stupid fish logo...

Re:Born again...

[steveo777]

Perhaps, but I think that'll be better than bumper stickers that read, "My Hadron is bigger than your Hadron"

BETTER HADRON COVERAGE

[mattnyc99]

This stuff is pretty cool, but The New Yorker's incredible science writer (who basically told the rest of the world about global warming) had a more in-your-face profile of the LHC last week, and Popular Mechanics has officially dubbed it "The World's Biggest Science Project." Sweet.

Re:BETTER HADRON COVERAGE

[Anonymous Coward]

Though what's depressing is something that both articles mention in brief:-

If the LHC doesn't find the Higgs, then that just about wraps it up for any further colliders. And, by extension, any further experiments into the fundamental whosis of the universe.

We've been looking for an answer to the question 'So, what's that made of then?' since the dawn of civilisation, it seems deeply sad that we could soon reach a point where, as a species, we shrug and say 'Dunno'.

Re:BETTER HADRON COVERAGE

[Mr. McGibby]

We've been looking for an answer to the question 'So, what's that made of then?' since the dawn of civilisation, it seems deeply sad that we could soon reach a point where, as a species, we shrug and say 'Dunno'.

I'm a big fan of spending lots of money on scientific research, but sometimes economics gets in the way. I would love to know the answers now too, but if the human economy just can't handle that much of an investment in basic research, then it can't.

Now, I personally think that the economy could probably spend 10 - 100 times more on basic research than it does and get a lot of good return on the investment. However, technology will progress in the meantime and hopefully, making more and more powerful colliders will become cheaper over time. Until the point at which making bigger colliders becomes cheap enough that governments will be willing to swallow the expense.

But I don't think that this is the end of particle physics. It just might delay it.

Re:BETTER HADRON COVERAGE

[jmtpi]

But I don't think that this is the end of particle physics. It just might delay it.

As a young person in the field, I would agree. But it would be a very depressing delay.....

If LHC fails to find physics beyond the Standard Model (or worse, does not even find the Higgs), then the ILC is on shaky ground. If the LHC really plays out as a disappointment (due to Nature or technical failure) and the ILC is cancelled, then particle physicists will run to astrophysics and neutrino physics in droves. A lot of attention would shift to learning about dark matter from space instead of from colliders. Collider physics would slow down for a long time, and the future might depend on how quickly really advanced accelerator technologies can be developed.

Let's hope for a rosier scenario.

graaaaaaaah

[Anonymous Coward]

I came to /. to GET AWAY from particle physics revision!

Re:graaaaaaaah

[Anonymous Coward]

Errr. So had I! :(

Please stop talking about power/energy!

[BlackPignouf]

I'm seriously getting sick of seeing kW/h or energy units used as consumption measure without any context.
Wow.. 'energy consumption = 14 trillon electron volts', you say?????
It's almost 7E-13 kWh! So I guess I could power trillions of LHC with just a liter of oil.

Re:Please stop talking about power/energy!

[treeves]

No. 14TeV is the energy of a single hadron, not the energy involved on the whole LHC.

So if the beam had a current of 1 amp (1 Coulomb / sec) then the energy of the particles in the beam would be 6.241×10^18 * 7x10^-13 = 4.3*10^6 kW*Hr. That's a lot of energy, and I'm guessing the beam currents are MUCH less than 1 amp. BTW, power = energy / time or work / time.

Mods are clueless on this one.

/. does it again!

[perturbed1]

There are more mistakes in the /. gist than in the NYTimes article -- which incidentally is a good summary for the LHC. Well, the writer was at CERN about a month ago, so I am assuming it took about that long to write it.

It is called the LHC -- Large Hadron Collider. Not the Hadron SuperCollider. The SuperCollider is dead. It was called the SSC. But it has passed on. It has ceased to be! It has expired and gone to meet its maker! Its a stiff! Bereft of line and rests in peaces in TX! It's kicked the bucket and shuffled off its mortal coil! (Gee. I wish I could write this about the M$! Grrr!!)

The energy consumption is 14 trillion electron volts?! Wt..? Last time, I checked the LHC could not run on days where the electricity prices were high. Actually, it can not run during winter for that reason. It and the detectors consume as much energy as you get out from a medium-sized nuclear reactor -- and that's why it sits partially in France and not fully in Switzerland. (France produces a whole lot more power than Switzerland.)

"The piece also goes into some detail on the expected experiments. " Huh? What expected experiments? The experiments have been in construction now for seven years. You mean expected results?!

Honestly, how many mistakes can you make in one paragraph??

Sorry about the rant, but I am so annoyed with the latest reports about M$'s threats, that I had to vent. I feel better now. Slightly.

Re:/. does it again!

[l0b0]

It and the detectors consume as much energy as you get out from a medium-sized nuclear reactor -- and that's why it sits partially in France and not fully in Switzerland. (France produces a whole lot more power than Switzerland.)

No, AFAIK the main reasons for placing CERN where it is were political (the location was decided in 1955, and the site extended into France in 1965, according to "Infinitely CERN"). Having the possibility to draw on electricity from two different countries (as they did during an outage in 2005) was incidental.

Re:/. does it again!

[vectra14]

It's a funny coincidence, but the may 14th issue of the New Yorker also had an article on the LHC.

It's much much much lighter on the details, but I found it to be a much more interesting read -- in particular because the author appears to have tried to talk to a number of people there and get a general feel for what people think about experimental physics these days.

You can read the whole text legally and for free (no reg) here:
http://www.newyorker.com/reporting/2007/05/14/0705 14fa_fact_kolbert

Re:/. does it again!

[perturbed1]

Sorry, you are right. Good catch.

Re:/. does it again!

[perturbed1]

And I got the SSC link wrong. Here it is: SSC

Re:/. does it again!

[jmtpi]

Both the NYT and New Yorker articles were pretty good. As an experimentalist, I was slightly perturbed at the rant from Nima Arkani-Hamed in the New Yorker piece. Paraphrasing, he basically says, "The experimentalists don't let us see their raw data," and then later says, "Theorists do the important work anyway by drawing broad conclusions rather than just looking at individual observations." But in fairness, the author of the piece also included some anti-theorist quotes from Sam Ting and Leon Lederman. So I guess it balances out.

Anyway, it is good to see experimental particle physics get some media attention.

Re:/. does it again!

[professorfalcon]

Let's just hope France and Switzerland don't go to war with each other.

Spiderman 2

[Hic sunt leones]

Just a casual observation: it seems somewhat ironic that the article describes as "spidermen" the physicists working on the collider, which will, among other things, make suns.
I don't know if it was intentional, but if it was, it's a clever and very subtle reference to the popular comic/movie.

Power consumption = 14 Tev... ORLY?

[DirtySouthAfrican]

Ignoring that a TeV is a unit of energy and not power, that's about 2e-6 joules... a flea sneezes more energetically than that. They mean that individual particles can reach this energy. Actual power consumption is probably enough to power a dozen DeLoreans.

Re:Power consumption = 14 Tev... ORLY?

[DirtySouthAfrican]

... *curls up and waits to be modded Redundant*

Re:Power consumption = 14 Tev... ORLY?

[Oink]

Actually, what you said is not quite correct either. That's the center of mass collisional energy. Individual particles can reach half that, or 7 TeV.

Re:Power consumption = 14 Tev... ORLY?

[jimbolauski]

Actual power consumption is probably enough to power a dozen DeLoreans. I think not 14.52 jigga watts of electricity is a lot.

14 trillion eV ?

[l2718]

The blurb above looks like a Dr. Evil quote -- I assume you realize that "14 trillion eV" is a miniscule amount of energy? It's about 2 micro Joules, or .5 microcalories.

On the scale of a single particle, this is a tremendous amount of energy (for comparison, the energy scale for chemical reactions such as combustion is a few eV). Imprtaing so much energy to a particle (as well as powering the detectors, cooling appartus etc) means the whole collider has a massive energy budget -- way way bigger than 14 trillion eV, or even <gasp>one Joule</gasp>. Actually, the power required (tens to of Megawatts, enough for a small city) is more impressive than the total energy expended (not so much since the energy is expended over a very short time).

There's a youtube of their IT manager

[porkThreeWays]

There's a youtube video out there (I really wish I could find it) and it has the IT manager for the project. I have to wonder a little bit about him because he was asked why they didn't go with the cell processor instead of Intel based processors. His answer was "The P4's have better floating point processing". I could understand a lot of reasons to go with the P4 because there are a lot of good x86 programmers out there and they could reuse a lot of code etc etc. Has anyone else seen this video?

Re:There's a youtube of their IT manager

[Anonymous Coward]

Have you considered the performance penalty Cell takes when using double precision?

Re:There's a youtube of their IT manager

[Axello]

I would think with a project that's 7 years in the making, that they settle on a stable technology in an early stage. Cell processors are nice, but were they available, oh let's say: last summer?

The early stages of the analysis are often in dedicated hardware, because general purpose processors are not fast enough. You need to connect those systems together as well. Then you need to debug these software beasts, since they need to make a good mathematical analysis 30 million times a second. And with 7000 people waiting for results, you don't want to be caught with a bug...

One more thing on processors:
There's always a better processor on the horizon. Wasn't it NASA that still uses 8086 processors in their Space Shuttle?

Re:There's a youtube of their IT manager

[bill_mcgonigle]

His answer was "The P4's have better floating point processing".

Yeah? From Wikipedia: "Due to the nature of its applications, Cell is optimized towards single precision floating point computation. The SPEs are capable of performing double precision calculations, albeit with an order of magnitude performance penalty."

So, maybe P4 fairs better? He might not be a blithering idiot. Note: the P4 code should run just fine on the latest Xeons with the Core architecture (a.k.a smokin').

IIRC the Athlons also do slightly better at FP in the current generation.

I have to do this:

[Trent Hawkins]

"Super collider? I never even met her."

kneepads? oh yeah...

[Anonymous Coward]

'The physicists, wearing hardhats, kneepads and safety harnesses

The kneepads are for when the Senators, Representatives, various goverment functionaries, and lobbyists visit.

Kickass

[Anonymous Coward]

This is going to be great. The LHC is for sure going generate miniature black holes and energy patterns that demonstrate the existence of extra dimensions, and us String Theory fanboys will be vindicated!!@

All you Supersymmetry fanboys will be eating your words! "Squarks" my ass! String Theory FTW!!1!

Two 7TeV Beams = 14TeV collision

[perturbed1]

14 TeV is the amount of energy that is in a collision from two 7TeV beams colliding. In this case, the beam means particles (protons) accelerated to carry 7TeV of momentum. But that's just one "particle". The LHC, there are many "buckets" of particles being stored and collided and the total stored energy around the whole ring is 360MegaJoules. It is fairly easy to calculate actually:

There are 2808 bunches around the ring, each containing 1.15x10^{11} protons each with 7TeV of momentum. 7TeV = 7x10^{12} x 1.602x10^{-19} Joules. You multiply it all out, you get 362MegaJoules stored in the beam around the LHC ring.

That's 1 small cruise ship of 10,000 tons moving at 30km/hour.

450 automobioles of 2tons moving at 100km/hour.

Is enough to melt 500kg of copper. (which is actually a worry if the beams "are lost" due to a magnet quench and they hit the vacuum pipe!)

Oh, btw, the power consumption of the LHC only (excluding the detectors) is ~120MW.

Re:Two 7TeV Beams = 14TeV collision

[kindbud]

Oh, btw, the power consumption of the LHC only (excluding the detectors) is ~120MW.

I am pretty sure that most of that 120MW is used to power the electromagnets that confine the beams.

14 TeV is the amount of energy that is in a collision from two 7TeV beams colliding. In this case, the beam means particles (protons) accelerated to carry 7TeV of momentum. But that's just one "particle". The LHC, there are many "buckets" of particles being stored and collided and the total stored energy around the whole ring is 360MegaJoules. It is fairly easy to calculate actually:

Yes, it is. :) It's just 6.23068624 × 10^-10 watt-hours. Of course, it's released over an extremely short time interval, which is why it seems so large when expressed in the less-familiar terms used in particle physics. But the actual energy released in the experiments is quite small compared to ordinary energy stores we're accustomed to using every day. Most of the juice is used to power the electromagnets and the other instruments.

Re:Two 7TeV Beams = 14TeV collision

[kindbud]

Way to not read the comment I'm replying to. My figure was for one 14 TeV collision. As the parent to my post out, there are many more particles accelerated to that energy level within the ring.

362 million joules = 100,555.556 watt hours

Re:Two 7TeV Beams = 14TeV collision

[perturbed1]

Err.... Actually, this power does not go into the electromagnets directly. The electromagnets happen to be superconducting magnets, which, once powered, do not require more current. That's not where the power goes. The power goes into keeping it cool. 18kW of synchrotron radiation is dumped into the cryogenics system. The syncrotron radiation is due to the relativistic charged particles curving under the influence of the magnetic fields, but this dumped energy needs to be extracted before it results in a quench. A quench is defined as a superconducting magnet, which has no resistivity, transitioning into the resistive phase, due to the temperature rising locally above the critical point. Here is an interesting link to the power budget of CERN: link As you will see, the LHC eats up little power (given its size) compared to the SPS (Super Proton Synchrotron) which has conventional magnets and has much smaller radius. The SPS delivers 450MeV protons to the LHC, which then accelerates them upto 14TeV. But the SPS eats up more power than the LHC due to its conventional magnets. Hurray for super-conductivity. ps. you may not have realized this, but might like to know that your post resulted in an excited discussion in at least one CERN corridor...

Re:Two 7TeV Beams = 14TeV collision

[kindbud]

Oh cool. :) I hope it's not along the lines of "How do we point this thing at that idiot so we can blow his brains out?"

Re:Two 7TeV Beams = 14TeV collision

[Anonymous Coward]

Totally not getting any of this without a car analogy. Also, we need units to be in MILES and MILES PER HOUR... hopefully involving cars.

Re:Two 7TeV Beams = 14TeV collision

[perturbed1]

Naa. We *have* thought about pointing it towards Redmond though. (They should try suing CERN. I am sure we'd love that.)

The conversation went "Oh, but we just paid so much money for the damn superconducting magnets? Why do they still eat so much power?" "Oh-oh" (Ok, there were no machine engineers around, but a bunch of physicists. The machine engineers though want to blow out the brains of physicists on a regular basis, who they consider idiots... So you see, it is all in good humor.) Luckily, we still remember how to calculate synchrotron losses. Sort of...

Hey Vegeta

[Anonymous Coward]

What does the scanner say about its power level?

obligatory

[perturbed1]

Actually there is a blatant mistake in the NYTimes article. It says that collisions wil happen 30 million times a second.

"Again and again and again -- 30 million times a second, in fact."

Nope. The LHC runs at 40MHz.... A number that is absolutely hard-coded into the design and can not be changed... Wrote an e-mail to the NYTimes. They are generally pretty good with correcting in due time.

Re:obligatory

[jmtpi]

Actually there is a blatant mistake in the NYTimes article. It says that collisions wil happen 30 million times a second.

"Again and again and again -- 30 million times a second, in fact."

Nope. The LHC runs at 40MHz.... A number that is absolutely hard-coded into the design and can not be changed... Wrote an e-mail to the NYTimes. They are generally pretty good with correcting in due time.

Are you sure this is wrong? Not every bucket has to be filled, right? An LHC PDF document says that there are 2808 bunches in the 26659 meter ring at peak luminosity.

Using Google as my calculator:
1 / (((26 658.883 m) / c) / 2 808) = 31.5773629 megahertz
or about 30 million collisions per second. But I didn't think about this too hard, so maybe you can point out my mistake.

Re:obligatory

[perturbed1]

OK, so you go to the bottom of the confusion. The LHC runs at 40MHz. All of the detector readout in all experiments is tuned to this number. If it would be off... ouch! The catch is that there are *empty* bunches. These known as the orbit, last for a few microseconds and what most detectors do during this time is to reset their front-ends which might have beserk with radiation. But really, the orbit gap comes from the insertion mechanism of the beam from the SPS to the LHC. Accounting for the fact that there are no collisions during orbit, there are 30 million collisions in one second *on average*. Saying that there are 30 million collisions a second, results in people like you, going ahead and calculating the MHz from that... because the clause "a second" implies "constant and repetitive" to some extent. "30 million collisions in one second" would be alright as well as saying "a second on average."

I am so humbled. NYTimes writer actually replied to my e-mail on this. I suggested to the NYTimes to add "on average" to this to clear up the confusion, to which he replied with " I might have said something like that if I had had more time after I discovered this little glitch. "

I remain, very much, a fan of the NYTimes...

C'mon editors...

[heatdeath]

14 trillion volts is not a measure of power consumption, it's an electric potential delta.

Re:C'mon editors...

[phaunt]

Except it's not about volts (V), it's about electronvolts (eV). That's a unit of energy, not power (as has been detailed numerous times in these comments).

Obligitory Futurama Quote

[baKanale]

So I says, "Supercollider? I just met her!" And then they built the supercollider. Thank you, you've been a great audience.

Ride On!

[Last Standing Footma]

Sweetser, thats the most sensible thing I have EVER heard regarding Standard Model. Could I invite you to give lectures to the place where I took my shiny & useless M.Sc. in Quantum Field Theory? :D

I don't get it.

[teal_]

Let me be the first to admit that I don't understand how this works. Will the mass of Slashdot users who pretend to understand follow suit, or will they shun me? :)

John Hodgman's take

[xzqx]

John Hodgman had a great take on the typo potential here in February's Wired. Please check out.

http://www.wired.com/wired/archive/15.02/bigquesti ons.html?pg=4#hadron

I want this camera...

[Cervantes]

... a 60-megapixel digital camera taking 40 million pictures a second. I want that camera. The data throughput must be staggering.

Of course, I'm curious how it can do 40 million pictures per second, if particles being spun around the track by superconductors can only collide 20 million times per second. I know it's a 17 mile track, but still, taking that as a base for the maximum speed you can get a particle going, it makes me wonder how you could push 60 million pixels worth of data over even a short span of cable, 40 million times per second... I'd love to see more info just on the camera, and how they manage to push that much data, that quickly.

Also, I wonder what's being done with the old supercollider that the US was building in Texas? Is it just sitting there, rusting?

Re:I want this camera...

[perturbed1]

Yes, the data throughput is staggering.

The collision are happening at 40MHz. (The NYTimes, got it wrong and says 30MHz. I dont know where you got the 20MHz number from. But nope.. everything at the LHC, detectors, everything runs at 40MHz.) The trick is to "trigger"...

Say, you have a huge library of books, and you only want to find those that have something to do with ... computers. Then you look at the title of the book and throw it out if it is about the structure of DNA. It is sort of like that. The "trigger" looks at the event, but only part of the event -- as seen by the detectors, and checks to see if there is something that might be interesting and new in there, such as a Higgs, or some supersymmetric particle. If not, then it discards it. So the pixel detector is not read out every 40MHz. It gets what is known as the L1A trigger, and reads out at 75kHz. Ok, that's still a lot of data!

You might be interested to know that CMS (and LHCb) use technology that is very similar to what the phone companies use. CMS use switchers to distribute the events arriving at 75kHz to a large cluster of computers. The data can not be written to disk at this speed, so they reduce this data further to ~100Hz and write to disk. This is called a higher-level trigger decision and has to be done under 40msec, which is the biggest challenge there. LHCb's L1A rates are higher as their data packets are smaller and they write to disk ~1000Hz. ATLAS does something completely different and reduces data in multiple steps rather than using switchers. But no, none of this is trivial by any means.

As for the SSC in TX, I think they filled it up mostly for some stupid reason. So nope, no chance of using it ever again.

Pictures of the "mundane" parts here

[iamlucky13]

Here is a map showing the layout of the LHC. It actually consists of two rings and a couple of linear accelerator stages so they aren't injecting cold particles into the high energy beam. Keep in mind, the main ring is 17 miles around and about 100 meters underground. A lot of the people living inside its circumference probably don't actually realize what's going on underneath their feet, other than the various CERN campuses spread around the ring and all the nerdy looking people going in and out. In fact, there will be millions of particles whizzing around the track at ~99.9999% the speed of light...circling the entire distance 10,000 times a second.

What you see in the NY Times slide show is basically the most impressive parts of the LHC, the incredibly complex and massive detectors assembled in huge underground vaults. The remainder, while still fairly complicated and interesting, is orders of magnitude simpler.

The rest of the collider is mostly a 3 meter diameter tunnel (pic), which has a track for getting people and equipment around it as needed, and the beam conduit. The physical tunnel is being reused from an older collider that was retired in 2000 to make way for this one, and I presume was dug with a tunnel boring machine.

The conduit (CAD rendering) itself is more than just a pipe. The most important part is the two vacuum pipes inside that the beam runs through, and the 9,000+ magnets around the pipes that electromagnetically constrain and accellerate the particles so they follow the 17 mile loop instead of smashing uselessly into the walls. It also contains the electrical lines that power the magnets, and helium lines that keep them cool. Some stray collisions are expected, so it also contains a little bit of radiation shielding, although I don't believe people are supposed to be in the tunnel when it is operating.

More Pictures
LHC Outreach Page
Map showing cities and Swiss/French border

Re:Pictures of the "mundane" parts here

[Captain Nitpick]

The rest of the collider is mostly a 3 meter diameter tunnel (pic), which has a track for getting people and equipment around it as needed, and the beam conduit. The physical tunnel is being reused from an older collider that was retired in 2000 to make way for this one, and I presume was dug with a tunnel boring machine.

CERN has a page about the [http://sl-div.web.cern.ch/sl-div/history/lep_doc. html construction of the LEP] collider, which previously occupied the tunnel. Three tunnel boring machines were used.

Re:Pictures of the "mundane" parts here

[Anonymous Coward]

Some stray collisions are expected, so it also contains a little bit of radiation shielding, although I don't believe people are supposed to be in the tunnel when it is operating.

I can't speak specifically about the LHC, but I once toured Cornell's particle accelerator, and there are huge (5-10 foot thick) concrete blocks in the detector room to protect people from X-rays when the accelerator is operating. It's not the collisions that cause the X-rays; rather, the X-rays are caused just by having these particles spinning around in the accelerator. To keep the particles moving in a circle, instead of a straight line, requires centripetal acceleration; accelerating a charged particle releases photons; the higher the acceleration, the higher the energy of the photons. The acceleration in this case is so high that X-rays are sprayed radially outward from the beam's circular path. In most parts of the accelerator, they just slam harmlessly into the ground surrounding the tunnel, but in the open space where the detector is, they need the concrete blocks. (You definitely don't want to be in the tunnel or on the wrong side of the concrete blocks when the accelerator is operating.)

They even use the accelerator as an X-ray source for experiments unrelated to colliding particles. (For this purpose, they additionally wiggle the particles back and forth--more acceleration--to get even more X-rays off.)

I'm not a particle physicist--just friends with one--so if any of that is inaccurate, please correct me.

Re:Pictures of the "mundane" parts here

[Anonymous Coward]

Very interesting. Actually, the detectors would be the most dangerous parts of the machine. Here they're deliberately smashing the nuclei together by crossing the streams (queue ghostbuster's quotes), so lot's of collisions are happening with the maximum energy.

Out in the tunnel, the particles generally just follow the circle, with minimal collisions. I don't know about the x-rays given off during accellerating, but it sounds reasonable to me. There may be some of this, too, but much less than in the detectors.

I suspect the tunnel isn't the greatest place to be during operation, but not the worst, either. However, they don't have the radiation shielding on the beam tubes to protect an empty concrete tunnel, so either there are activated nuclei in the beam tube walls that pose some risk to workers when the accellerator is shut down, or there are foreseeable instances when it is desireable to have workers in the tunnel during operation.

Corrected summary

[l0b0]

Circumference = 27 kilometers (~17.5 miles), cost = 8 billion USD (presumably, and only for the construction), energy consumption = ~120 MW, particle energy = 14 TeV.

More interesting statistics are available on the LHC outreach site.

What a half-assed attempt at a submission. Even the title is a mix between the SSC and the LHC.

Where's Gordon Freeman?

[Hausenwulf]

Sorry, I can't help but think of Half-Life2 when I see articles like these. ;)

Re:Where's Gordon Freeman?

[iamlucky13]

Did you check out the photographs of the Compact Muon Solenoid? It would fit in perfectly at Black Mesa.

I swear, if I don't see a level in Episode 2 or 3 involving the LHC and the CMS, I'm going to go gravity-gun-equipped-particle-phsyical on somebody's ass! HL2 and Episode 1 didn't have quite enough gigantic, super-expensive and complex equipment malfunctioning catastrophically to satiate my inner geek.

It can't be too much of a plot stretch to have Dr. Kleiner modifying the Compact Muon Solenoid to trigger lepton-catalyzed resonance cascades as a controlled means of opening portals. He'll just have to be careful to maintain steady electrical and helium supplies or a quench of the superconducting magnets could occur. The resulting spallation from relativistic particle collisions on the beam pipe wall would almost certainly cause gluino-poisoning of the portal's singularity...

The techno-babble from Half Life 1 was fun and well-delivered, even if utterly meaningless.

Yes, you will definitely need it

[Anonymous Coward]

So start thinking how you are going to power it...

The Web!

[Roger W Moore]

The problem with something this expensive is that the average person, including myself, cannot see, even if it provides every answer they hope for it, how that will change my everyday life in the least.

Yet here you are posting on a website. The web was developed at CERN for those of us working in large, international collaborations to communicate. It also turned out to be pretty good at letting everyone else communicate too. So without CERN there would be no Slashdot for you to post your comments on how you don't think science has done anything for you!

Per proton collision

[Roger W Moore]

This is the maximum energy available per proton collision - most collisions actually occur at far lower energies because the proton is made up of quarks and gluons, each of which only carry a part of the total energy, and these are what actually collide.

To get an idea of how big this really is imagine you gave all the protons in 1 gram of hydrogen the same energy. In 1g there are Avogadro's number of protons i.e. 6e23 so you would need ~1.2e18 joules!

IIRC the LHC projected luminsoity is something like 1e16 protons in the ring. However, accelerators are very inefficient and only a tiny fraction of the energy used is translated into proton energy. In the case of the LHC a considerable fraction of the energy is actually spent in refrigeration plants producing liquid helium to keep the superconducting magnets superconducting.

Looking at that map...

[RealGrouchy]

It looks like a good way to smuggle particles between France and Switzerland!

Better keep an eye on these "scientists"...

- RG>

Go on -- shrink Earth to the size of a pea

[Baldrson]

I bought a new puppy. But what to name him? It was a toss-up between "John Galt" and "Lexx". My wife and I went round and round about the crucial decision. We finally settled on "Lexx"; just in the nick of time it seems.

hadron?

[azenpunk]

anyone else misread the title? yeah i'm sure it's got a real 'lengthy profile'

Next week's headlines

[Evil Cretin]

the three million DVDs worth of data it will spew forth every year.
Next week's headlines:

"CERN Under Investigation by MPAA. Lab Director Declines to Comment."

Flying Cars

[bill_mcgonigle]

how that will change my everyday life

You're going to get a flying car, OK?

Well, maybe. See, the LHC is going to be able to smash things at the Weak Scale energy, which is where we need to look (at what comes out of smashed things) to pick among many theories of how the universe works. Depending on the results, dozens of models will be ruled out, and, if we're lucky, one will be left standing.

This model will likely contain a theory of quantum gravity. We have lots of ideas about how quantum physics and gravity might align, but we don't know which, if any, are right.

Now, to make your flying car is going to require some engineering work. That'll have to figure out how to cancel out gravity. Nobody knows if this is possible or if we can do it, but if we can and it is we're going to have to know how gravity works first.

So the LHC is the first step to getting you a flying car. I'm just not sure that we want people who judge 'basic science is worthless' to be making flight judgments in flying cars.

Based on this quote FTA...

[Samah]

"If you see nothing," said a Cern physicist, John Ellis, "in some sense then, we theorists have been talking rubbish for the last 35 years."
Cue the creationists and their banana and peanut butter solutions.

You know what?

[Anonymous Coward]

14 trillion electron volts?! They really should switch to CFLs.

*bum-dum-ching!
Thank you everyone, goodnight.

Does not compute

[StikyPad]

(size = 17 miles, cost = 8 billion, energy consumption = 14 trillon electron volts)

For the old school among us, that's 59,840 cubits, 370 metric tons of gold, and 1.18170471 x 10^-19 foot pounds, respectively.

Or about 3 Libraries of Congress accelerating at about 1.72 x 10^-183 m/s/s.

Re:Does not compute

[Anonymous Coward]

The day it turns on will be a moment of truth for Cern, which has spent 13 years building the collider, and for the world's physicists, who have staked their credibility and their careers, not to mention all those billions of dollars, on the conviction that they are within touching distance of the answer to the question about fundamental discoveries about the universe. The answer to that question is

42

First collision

[professorfalcon]

The first collision has already occurred, with terrible consequences.

Poor desk.