Yes I think I was a little harsh on the low signal to noise comment. I recant that poor phrasing of words now. Its because mostly in recent years I've seen the 'crazy' papers pointed out to me in arXiv than the large body of well regarded scientific works that I have this slightly unfair opinion. I still stand by my main point that on arXiv the papers are not peer reviewed (and this is in my opinion a good thing) so the reader should be aware that the conclusions should not a prior a be held to the same level of scientific fact as a peer reviewed paper.
ah didnt realise they had moderators, thanks for the correction. So there is atleast one layer of quaility control to keep the crazies out. When I submitted my papers I just clicked upload and didnt realise that somebody reviewed it. Glad nobody objected to mine:)
But that was 1998 where a) the general population was just getting online and b) pretty much only scientists knew about arXiv. There is a lot of peer reviewed stuff on there (every paper submitted to a journal tends to be submitted) but as more less mainstream scientists have access, you regretably get more noise. Looking at Oct 2007 for hep-th and assuming that it would be mentioned in the summary is its published or going to be published (and trust me people mention this...), out of the first 25, 12 are published in a journal and or conference proceedings. So less than 50% were blessed by some form of peer review. And its the other 50% tend to be the most sensational:)
Note I still think its very valuable for to have a place where non-peer reviewed material can be uploaded as well as peer reviewed but if its not peer-reviewed its a lot more likely to be incorrect somehow and the reader needs to be aware of that.
Oh exactly. I think the future is a peer reviewed online journal. I think arXiv provides a very valuable service as is for the distribution of knowledge. Right now it has a copy of basically every particle physics paper published and I assume this is true for some other fields too. Many times I grab the arXiv copy over the journal copy as its more convient. So all the journal does is basically place a peer reviewed stamp of approval on the online arXiv paper and this could easily be replaced with a online journal in the future.
I am strongly against journal sub fees as I believe which that the knowledge contained in scientific papers (doubly so for public funded ones) should be availible to all and not only accessable to people willing to pay the high cost of a journal subscription fee. CERN is pushing open journals for that very reason and that may evolve into a respected online peer reviewed journal which will compliment arXiv nicely.
Likewise, every particle physicist also puts his paper there before they are published (my three are all there). While it is great as a source of open information, one thing to bear in mind is that it is not peer reviewed, *anybody* can stick *anything* there. This is the major reason why we still unfortunately need paper journals. We need somebody to read it and say yes this follows basic scientific procedures and to the best of his/her knowledge there are no mistakes. Because theres a fairly low signal to noise on arXiv and whats there is not guaranteed at all to be of proper scientific merit and correctness.
Traditionally particle physics doesnt use the data to "generate" theories as such. We use the data to measure various properties (W mass, Z->ll mass spectrum, lepton pt spectra), looking for descrepances with the theory predictions. Then we (hopefully) go, oops this doesnt agree with the theory, we'ld better come up with another explaination. Recently its been, ah SM predictions confirmed *again*.
I can only really speak for CMS (one of the two big general purpose experiments) but every experiment does similar things. Basically the data is split into smaller datasets based on what we decided was interesting in the event (basically what trigger fired). So we split it into events with electrons, muons, photons, jets (yes events will have multiple of the above but dont worry about how we deal with it). Then each physicist looking for a specific signature (ie a top quark, or in my case high mass e+e- pair) runs their custom homebrew statistical analysis (which use common tools) to pick out the events they are interested in. There are also physicists who run custom designed programs to pick out *any* descrepancy from theory predictions but as they are more general, they arent as senstive as a dedicated analysis on a single channel.
No I'm with the parent. And I'm coming for the user/scientist side. The admins at scientific labs like CERN are basically doing a heroic job despite the best efforts of their users to be as awkward as possible.
He's right, its almost impossible to get physicists to do what you want and by god if it goes down theres hell to pay, even if it *them* who brought it down doing something the admins told them not to. Admins cant really lock anything down and if they try to its circumvented and/or bitterly complained about. Plus they have to allow the user to run whatever programs they want as they mainly use (very poorly written) custom code. It all boils down to physicists being obsessed about their research to the point that getting it done is the *most important* thing and all else pales into significance.
Again I mention that I'm physicist and I know I'm guilty of this, I've taken down the UK particle physics cluter farm (the tier 1 in grid speak) but these days I usually buy them a beer afterwards to make up for it.
trust me its not fun. Physicists are demanding, require unreasonable ungodly amounts of storage and computing power and will do whater the hell they like with it, usally fecking up the system in new and interesting ways. Even the grid isnt enough, we could use more cpu. I'm a physicist at cern (posting from the CMS control room, was there yestarday, twas exciting) and I wouldnt want to be my sys admin;)
Incidently offtopic, the LHC is down at the moment and has been all day. Apparently its something about a lost patrol.
I thought the Inquirer hated everybody and mostly runs sensationalist news stories that turn out to be a bit iffy in the end. To me they have less credibility than some random guy's blog.
In the interests of fairness this is maybe because I don't regularly read them, only whats picked up by slashdot/other news stories which tend by their very nature to be sensationalist and often made up. Which is why I don't regularly read them:)
Thanks for the rebutal. Actually I was just tired (I had just woken up) which may of been why the tone was a little off. Long night trying get our damn software to work for the big turn on. I wouldnt say I'm particularly intelligent but I do have a DPhil from Oxford in the subject in hand. I cant prove this but I can atleast show I have write access to a cern webspace.
As for the technobabble, its like any field, if you use the jargon day in day out then its pretty easy to understand. Theres another post that explains it all lower down and you'll see theres not really much too it, it just sounds complicated.
Also I really really suck at spelling, you should have seen my thesis, I managed to miss-spell "uncertainty" 6 different ways on the same page:)
I understand every word. Any experimental particle physicist does. I will conceed its not clearn to non-experts.
However an important feature of a luminosity and diffractive phyics detector such as TOTEM is its coverage, ie at what angle it can go to. Therefor its pseudorapidy range (basically the angle it covers from the beam line) and the distances of the roman pots from CMS (and effecting the angular coverage of this part of the detector) are key peices of information. This is perhaps the most important thing to know about TOTEM.
Some do, most dont. However it is the offical proganda:)
Basically if its in the exact right place and we get very lucky we could see it early next year. We could also win the lottery (to be fair the chances of seeing the Higgs straight away isnt as bad as that but its not good).
Signed,
A particle physicist who hopes the Higgs doesnt exist as that would be a disappointment.
Um, are you joking. I'm from the UK. I get 5 weeks holiday as a starting employee. Its a government job, technically so its a little on the good side for the UK but the rest of europe has it better. This amount of holiday increases with time served too...
I've lived in the states, and in my experience car insurance is cheaper there but in the UK we have higher salaries so it probably evens out.
As for health insurance, national insurance is about 7% of my salary (before tax) so you're doing a bit better there but this also will provide me a small pension (in theory, maybe, its something but you need something else too)
Yes the coolest and most impressive thing about it in my opinion is that it is 99% scientifically accurate and condenses the science into a pretty reasonable and semi complete explanation without losing too much. The only artistic liberty I spotted is that it claims we should spot the Higgs boson straight away which is wishful thinking:)
it was heavily featured in the comments of the previous LHC article a week ago, which is why you think its a dupe but technically its not. Or maybe it is, does reposting comments in a previous article as a new article count as a dupe?
actually when I first heard about it, I thought it was a fermilab discovery. Theres been a lot of rumors flying around that CDF had something big. If this was it, I'm disappointed. Also for the record, fermilab is still very relevent. The most likely place for the Higgs given current experimental evidence is in the second easiest place for the Tevatron experiments to see it (115 GeV) but the hardest place for the LHC experiments to see it. So the Tevatron could well scoop the LHC, its not over.
Incidently, why is 115 GeV so hard for the LHC to see. Well at this point the Higgs is too light to decay to WW or ZZ (the W has mass of 80 GeV, Z 91GeV so needs Higgs mass of 160-180 GeV to open those channels). This means that a light Higgs of 115 GeV will decay into the heaviest particle availible to it (remember the more massive the particle, the strong the Higgs coupling) which is the bottom quark. At the Tevatron, the backgrounds to two bottom quarks isnt soo bad and the experimenters are all very experienced at tagging b quarks using their detectors. At the LHC you might as well give up so you have to go through the very rare vector boson fusion channel using a top quark loop to get two photons which itself has a bit of nasty background. Hence you will need 10 fb-1 of data which is *atleast* a years running at the LHC.
you're telling me. Trying to figure out if the damn thing is working is an epic task. It takes hundreds of scientists, all testing little parts to commission these things. And trust me everything that can go wrong will go wrong. Right now I'm writing monitoring software to ensure that we can trigger electrons and photons and to diagnose problems when they occur and its a huge pain in the ass. And when we think its working, even then we will have a round the clock team in place to continuously monitor it addition to the team that actually operates it.
dont worry, we have it covered. Part of my job is to run simulations of startup at the LHC and prepare for it. I've been extensively playing halflife as result, I'm sure thats what my boss meant:)
I always find the most impressive things about the detectors is the cabling that you have to do. The CMS ECAL has at least 61,200 cables to read out all the the crystals, the tracker (first photo) also has thousands and thousands of cables. Trying to wire the damn thing up is an epic task (one I'm happy to have avoided) and trust me, you dont want to screw up.
Look I've never understood what the LHC is going to kill us all thing. I'm a physicist working on the CMS experiment so perhaps I can explain what we are going to do more clearly. All we plan to do is take two proton beams or 'streams' and then cross them. Why is everybody so worried?
Its worth adding that laptops are powercycled more often and its the heating up/ cooling down cycle which kills it so while both chips have the same problem, the problem (for now) is mainly manifested in laptop chips.
no, these people took the time to say they dont want to buy things from telemarketers. This is not the same as wont and this is why telemarketers opposed the scheme as they could talk round nice people who find it difficult to say no to a person into buying crap.
The list is a wonderfull thing, not only did it cut my calls to nothing, it also helps people who are too nice/gulible stop getting fleaced. From a business perspective, well its nice to know that you arent taking advantage of your customers but you probably make less profit. But hey being ethical is a good thing in its own right.
Slashdot Mirror
Yes I think I was a little harsh on the low signal to noise comment. I recant that poor phrasing of words now. Its because mostly in recent years I've seen the 'crazy' papers pointed out to me in arXiv than the large body of well regarded scientific works that I have this slightly unfair opinion. I still stand by my main point that on arXiv the papers are not peer reviewed (and this is in my opinion a good thing) so the reader should be aware that the conclusions should not a prior a be held to the same level of scientific fact as a peer reviewed paper.
ah didnt realise they had moderators, thanks for the correction. So there is atleast one layer of quaility control to keep the crazies out. When I submitted my papers I just clicked upload and didnt realise that somebody reviewed it. Glad nobody objected to mine :)
But that was 1998 where a) the general population was just getting online and b) pretty much only scientists knew about arXiv. There is a lot of peer reviewed stuff on there (every paper submitted to a journal tends to be submitted) but as more less mainstream scientists have access, you regretably get more noise. Looking at Oct 2007 for hep-th and assuming that it would be mentioned in the summary is its published or going to be published (and trust me people mention this...), out of the first 25, 12 are published in a journal and or conference proceedings. So less than 50% were blessed by some form of peer review. And its the other 50% tend to be the most sensational :)
Note I still think its very valuable for to have a place where non-peer reviewed material can be uploaded as well as peer reviewed but if its not peer-reviewed its a lot more likely to be incorrect somehow and the reader needs to be aware of that.
Oh exactly. I think the future is a peer reviewed online journal. I think arXiv provides a very valuable service as is for the distribution of knowledge. Right now it has a copy of basically every particle physics paper published and I assume this is true for some other fields too. Many times I grab the arXiv copy over the journal copy as its more convient. So all the journal does is basically place a peer reviewed stamp of approval on the online arXiv paper and this could easily be replaced with a online journal in the future.
I am strongly against journal sub fees as I believe which that the knowledge contained in scientific papers (doubly so for public funded ones) should be availible to all and not only accessable to people willing to pay the high cost of a journal subscription fee. CERN is pushing open journals for that very reason and that may evolve into a respected online peer reviewed journal which will compliment arXiv nicely.
Likewise, every particle physicist also puts his paper there before they are published (my three are all there). While it is great as a source of open information, one thing to bear in mind is that it is not peer reviewed, *anybody* can stick *anything* there. This is the major reason why we still unfortunately need paper journals. We need somebody to read it and say yes this follows basic scientific procedures and to the best of his/her knowledge there are no mistakes. Because theres a fairly low signal to noise on arXiv and whats there is not guaranteed at all to be of proper scientific merit and correctness.
Traditionally particle physics doesnt use the data to "generate" theories as such. We use the data to measure various properties (W mass, Z->ll mass spectrum, lepton pt spectra), looking for descrepances with the theory predictions. Then we (hopefully) go, oops this doesnt agree with the theory, we'ld better come up with another explaination. Recently its been, ah SM predictions confirmed *again*.
I can only really speak for CMS (one of the two big general purpose experiments) but every experiment does similar things. Basically the data is split into smaller datasets based on what we decided was interesting in the event (basically what trigger fired). So we split it into events with electrons, muons, photons, jets (yes events will have multiple of the above but dont worry about how we deal with it). Then each physicist looking for a specific signature (ie a top quark, or in my case high mass e+e- pair) runs their custom homebrew statistical analysis (which use common tools) to pick out the events they are interested in. There are also physicists who run custom designed programs to pick out *any* descrepancy from theory predictions but as they are more general, they arent as senstive as a dedicated analysis on a single channel.
No I'm with the parent. And I'm coming for the user/scientist side. The admins at scientific labs like CERN are basically doing a heroic job despite the best efforts of their users to be as awkward as possible.
He's right, its almost impossible to get physicists to do what you want and by god if it goes down theres hell to pay, even if it *them* who brought it down doing something the admins told them not to. Admins cant really lock anything down and if they try to its circumvented and/or bitterly complained about. Plus they have to allow the user to run whatever programs they want as they mainly use (very poorly written) custom code. It all boils down to physicists being obsessed about their research to the point that getting it done is the *most important* thing and all else pales into significance.
Again I mention that I'm physicist and I know I'm guilty of this, I've taken down the UK particle physics cluter farm (the tier 1 in grid speak) but these days I usually buy them a beer afterwards to make up for it.
I think you now start to see the extent of the problem. Seriously the sys admins are the outgoing ones at my work :)
trust me its not fun. Physicists are demanding, require unreasonable ungodly amounts of storage and computing power and will do whater the hell they like with it, usally fecking up the system in new and interesting ways. Even the grid isnt enough, we could use more cpu. I'm a physicist at cern (posting from the CMS control room, was there yestarday, twas exciting) and I wouldnt want to be my sys admin ;)
Incidently offtopic, the LHC is down at the moment and has been all day. Apparently its something about a lost patrol.
I thought the Inquirer hated everybody and mostly runs sensationalist news stories that turn out to be a bit iffy in the end. To me they have less credibility than some random guy's blog.
:)
In the interests of fairness this is maybe because I don't regularly read them, only whats picked up by slashdot/other news stories which tend by their very nature to be sensationalist and often made up. Which is why I don't regularly read them
Thanks for the rebutal. Actually I was just tired (I had just woken up) which may of been why the tone was a little off. Long night trying get our damn software to work for the big turn on. I wouldnt say I'm particularly intelligent but I do have a DPhil from Oxford in the subject in hand. I cant prove this but I can atleast show I have write access to a cern webspace.
:)
As for the technobabble, its like any field, if you use the jargon day in day out then its pretty easy to understand. Theres another post that explains it all lower down and you'll see theres not really much too it, it just sounds complicated.
Also I really really suck at spelling, you should have seen my thesis, I managed to miss-spell "uncertainty" 6 different ways on the same page
I understand every word. Any experimental particle physicist does. I will conceed its not clearn to non-experts.
However an important feature of a luminosity and diffractive phyics detector such as TOTEM is its coverage, ie at what angle it can go to. Therefor its pseudorapidy range (basically the angle it covers from the beam line) and the distances of the roman pots from CMS (and effecting the angular coverage of this part of the detector) are key peices of information. This is perhaps the most important thing to know about TOTEM.
Some do, most dont. However it is the offical proganda :)
Basically if its in the exact right place and we get very lucky we could see it early next year. We could also win the lottery (to be fair the chances of seeing the Higgs straight away isnt as bad as that but its not good).
Signed,
A particle physicist who hopes the Higgs doesnt exist as that would be a disappointment.
Um, are you joking. I'm from the UK. I get 5 weeks holiday as a starting employee. Its a government job, technically so its a little on the good side for the UK but the rest of europe has it better. This amount of holiday increases with time served too...
I've lived in the states, and in my experience car insurance is cheaper there but in the UK we have higher salaries so it probably evens out.
As for health insurance, national insurance is about 7% of my salary (before tax) so you're doing a bit better there but this also will provide me a small pension (in theory, maybe, its something but you need something else too)
Yes the coolest and most impressive thing about it in my opinion is that it is 99% scientifically accurate and condenses the science into a pretty reasonable and semi complete explanation without losing too much. The only artistic liberty I spotted is that it claims we should spot the Higgs boson straight away which is wishful thinking :)
it was heavily featured in the comments of the previous LHC article a week ago, which is why you think its a dupe but technically its not. Or maybe it is, does reposting comments in a previous article as a new article count as a dupe?
examples here and here
actually when I first heard about it, I thought it was a fermilab discovery. Theres been a lot of rumors flying around that CDF had something big. If this was it, I'm disappointed. Also for the record, fermilab is still very relevent. The most likely place for the Higgs given current experimental evidence is in the second easiest place for the Tevatron experiments to see it (115 GeV) but the hardest place for the LHC experiments to see it. So the Tevatron could well scoop the LHC, its not over.
Incidently, why is 115 GeV so hard for the LHC to see. Well at this point the Higgs is too light to decay to WW or ZZ (the W has mass of 80 GeV, Z 91GeV so needs Higgs mass of 160-180 GeV to open those channels). This means that a light Higgs of 115 GeV will decay into the heaviest particle availible to it (remember the more massive the particle, the strong the Higgs coupling) which is the bottom quark. At the Tevatron, the backgrounds to two bottom quarks isnt soo bad and the experimenters are all very experienced at tagging b quarks using their detectors. At the LHC you might as well give up so you have to go through the very rare vector boson fusion channel using a top quark loop to get two photons which itself has a bit of nasty background. Hence you will need 10 fb-1 of data which is *atleast* a years running at the LHC.
you're telling me. Trying to figure out if the damn thing is working is an epic task. It takes hundreds of scientists, all testing little parts to commission these things. And trust me everything that can go wrong will go wrong. Right now I'm writing monitoring software to ensure that we can trigger electrons and photons and to diagnose problems when they occur and its a huge pain in the ass. And when we think its working, even then we will have a round the clock team in place to continuously monitor it addition to the team that actually operates it.
dont worry, we have it covered. Part of my job is to run simulations of startup at the LHC and prepare for it. I've been extensively playing halflife as result, I'm sure thats what my boss meant :)
I always find the most impressive things about the detectors is the cabling that you have to do. The CMS ECAL has at least 61,200 cables to read out all the the crystals, the tracker (first photo) also has thousands and thousands of cables. Trying to wire the damn thing up is an epic task (one I'm happy to have avoided) and trust me, you dont want to screw up.
Look I've never understood what the LHC is going to kill us all thing. I'm a physicist working on the CMS experiment so perhaps I can explain what we are going to do more clearly. All we plan to do is take two proton beams or 'streams' and then cross them. Why is everybody so worried?
You're not the first person to think so. It is suspicious that no answer is actually given....
Its worth adding that laptops are powercycled more often and its the heating up/ cooling down cycle which kills it so while both chips have the same problem, the problem (for now) is mainly manifested in laptop chips.
and was that Bose-Einstein condenstate 27km long? This is news because its a huge massive object cooled down to 1.9K.
no, these people took the time to say they dont want to buy things from telemarketers. This is not the same as wont and this is why telemarketers opposed the scheme as they could talk round nice people who find it difficult to say no to a person into buying crap.
The list is a wonderfull thing, not only did it cut my calls to nothing, it also helps people who are too nice/gulible stop getting fleaced. From a business perspective, well its nice to know that you arent taking advantage of your customers but you probably make less profit. But hey being ethical is a good thing in its own right.