Supersymmetry theory in doubt. Researchers detect rare particle decay at LHC.(bbc.co.uk)
bbc.co.uk
Supersymmetry theory in doubt. Researchers detect rare particle decay at LHC.
http://www.bbc.co.uk/news/science-environment-20300100
37 comments
I would just like to take a moment here to draw attention to the fact that the planned Superconducting Supercollider would have been even more capable at probing supersymmetry than the LHC and had it not been cancelled it would have been operating for well over a decade by now.
That time frame is not really accurate. Big accelerators, like many massive projects, are always years behind schedule. Back before the SSC was canceled, it and the LHC were both scheduled to turn on about a decade ago. But since the LHC actually got built, it experienced the real-life hiccups that would have delayed the SSC by years too.
I believe you are mistaken. The LEP and the SSC started early construction at about the same time, and the SSC was cancelled in the early 90s while the LEP started operations in '89. Construction of the LHC did not begin until the late 90s, well after the SSC had been cancelled and operations began about a decade after construction started. Even taking into account thee advantage the LHC had in being able to reuse the LEP tunnels and some of the existing infrastructure the likelihood of the SSC being able to become operational in the early 2000s is fairly high.
I guess we'll continue to disagree in the absence of an expert. My information comes from a discussion I had with two professors who migrated to CMS at LHC after the SSC was canceled. They agreed that the real tragedy of the loss of the SSC was the higher energy, and that with realistic estimates for the SSC schedule the timing advantage would have been minimal.
World's Toughest: Fixes Atom Smasher (S2E8) had a really interesting segment why the LHC took so long to get into service. (it's on hulu and netflix)
http://www.hulu.com/watch/176546#i0,p6,s2,d0
http://www.hulu.com/watch/176546#i0,p6,s2,d0
[deleted]
Useful links here:
http://profmattstrassler.com/2012/11/12/first-news-from-kyot...
http://www.math.columbia.edu/~woit/wordpress/?p=5264
Talk is here (follow password instructions): http://kds.kek.jp/getFile.py/access?contribId=61&session...
http://profmattstrassler.com/2012/11/12/first-news-from-kyot...
http://www.math.columbia.edu/~woit/wordpress/?p=5264
Talk is here (follow password instructions): http://kds.kek.jp/getFile.py/access?contribId=61&session...
I can personally vouch for Matt Strassler's writing, he is one of the most trusted and readable theorists in the field.
Thanks! To quote the shortest and much less sensationalistic summary from the second link:
"The B(s)->mu+mu- results from LHCb are out providing good agreement with the Standard Model, and new, strong limits on possible Supersymetry models"
"The B(s)->mu+mu- results from LHCb are out providing good agreement with the Standard Model, and new, strong limits on possible Supersymetry models"
Humans are running in a relay marathon of knowledge. Physics always seems to stagnate, then jump. The jumps come when a bunch of smart people can collocate and communicate. That's the recipe, and that's the only recipe. It's hard to share the energy in the room when you are not in the same room.
The cause of the jump though is not a bunch of people getting together, it's someone crazy enough to throw the first stone. It's someone crazy enough to question the structure science has created. It's someone daring enough to break it all apart, for the benefit of humanity, to let us rebuild and get closer to the correct path. One person starts a revolution. All the smart people look at all the pieces that broke and see how they can fit together in a new way.
I can't see this happening in 'new physics'. Yes, they are doing amazing things, things no one has ever been daring enough to do before. But quite frankly, they aren't diverse enough to solve their own problems they created. It's incredibly hard to solve the problems you made. There are no analogies to the problems physics is asking as of yet. To get analogies, you have to have people wander into your problem and say 'Hey! I was doing something like that for my Neuroscience research yesterday, maybe there's a connection!'. We aren't going to get that though, Physics has gone too far down the hole to relate to other fields. Unless they do what they always do, and just make new ones.
The cause of the jump though is not a bunch of people getting together, it's someone crazy enough to throw the first stone. It's someone crazy enough to question the structure science has created. It's someone daring enough to break it all apart, for the benefit of humanity, to let us rebuild and get closer to the correct path. One person starts a revolution. All the smart people look at all the pieces that broke and see how they can fit together in a new way.
I can't see this happening in 'new physics'. Yes, they are doing amazing things, things no one has ever been daring enough to do before. But quite frankly, they aren't diverse enough to solve their own problems they created. It's incredibly hard to solve the problems you made. There are no analogies to the problems physics is asking as of yet. To get analogies, you have to have people wander into your problem and say 'Hey! I was doing something like that for my Neuroscience research yesterday, maybe there's a connection!'. We aren't going to get that though, Physics has gone too far down the hole to relate to other fields. Unless they do what they always do, and just make new ones.
You must be watching different physics research than me. I see a huge variety of crazy-ass physics proposed all the time. Unfortunately it all keeps turning out to be wrong.
The problem with physics these days is that no "sharp" new data is turning up. Instead of turning up a new family of particles in an accelerator, we find big invisible blobs of dark matter. We are getting loads of fascinating unexplained data, but there are few bright line tests that can use it to rule in or out new theories.
The problem with physics these days is that no "sharp" new data is turning up. Instead of turning up a new family of particles in an accelerator, we find big invisible blobs of dark matter. We are getting loads of fascinating unexplained data, but there are few bright line tests that can use it to rule in or out new theories.
Welcome to the "Brave New World".
Huxley was right: http://youtube.com/watch?v=1ygIqLJnBJI
It's not like we were never warned.
Huxley was right: http://youtube.com/watch?v=1ygIqLJnBJI
It's not like we were never warned.
There is an interesting discussion about this on Reddit:
http://www.reddit.com/r/science/comments/13293t/supersymmetr...
http://www.reddit.com/r/science/comments/13293t/supersymmetr...
can anyone confirm my understanding of the basic physics here?
they are observing a transition from one particle to another that involves a process whose probability depends on "all particles" in some weird sense, because it includes particle-antiparticle pairs (so is affected by vacuum fluctuations?).
because of this, they have a weird situation where an experimental result depends on all possible particles (below some energy cutoff i guess).
and that is why it's a good test for standard model v super-symmetry. because super-symmetry (to be symmetric) predicts a bunch more particles. and if those are real, we would see something different.
i am not sure where i got this from, but it seemed to be implied by one of the links here...
they are observing a transition from one particle to another that involves a process whose probability depends on "all particles" in some weird sense, because it includes particle-antiparticle pairs (so is affected by vacuum fluctuations?).
because of this, they have a weird situation where an experimental result depends on all possible particles (below some energy cutoff i guess).
and that is why it's a good test for standard model v super-symmetry. because super-symmetry (to be symmetric) predicts a bunch more particles. and if those are real, we would see something different.
i am not sure where i got this from, but it seemed to be implied by one of the links here...
Yep, you've pretty much got it right. It is an indirect probe of new physics, not a direct probe. However, that method is well established. Some of the strongest constraints for new physics come from things like neutron dipole moment and studies of the g-factor of the muon (see g-2 or "g minus 2" online). These indirect methods make use of the virtual particles that arise from vacuum fluctuations in ways that are cleanly calculable (and thus make quantitative predictions).
All that said, SUSY has about 100 free parameters in the model, and all of these LHC searches hoped to find SUSY in the easiest of places, even though there is no firm prediction from the theory. Simply put, for a long time to come, SUSY can be "tuned" to remain consistent with all existing physical data.
All that said, SUSY has about 100 free parameters in the model, and all of these LHC searches hoped to find SUSY in the easiest of places, even though there is no firm prediction from the theory. Simply put, for a long time to come, SUSY can be "tuned" to remain consistent with all existing physical data.
The "doubt" seems to have been refuted here:
http://motls.blogspot.cz/2012/11/superstringy-compactificati...
http://motls.blogspot.cz/2012/11/superstringy-compactificati...
Patience my good people. We all remember what happened the last time there was a rare particle delay...
Out of curiosity: what are you referring to?
The barman says "We don't serve neutrinos here"
A neutrino walks into a bar.
A neutrino walks into a bar.
Probably the faster than light neutrino a little while back. Turned out to be a loose cable if I recall correctly.
I have to give the news media credit for not subsequently reporting:
"Experts Report Loose Cables Probable Method of Faster-Than-Light-Travel! How You Will Soon Make the Kessel Run in Less Than Twelve Parsecs."
"Experts Report Loose Cables Probable Method of Faster-Than-Light-Travel! How You Will Soon Make the Kessel Run in Less Than Twelve Parsecs."
http://www.nature.com/news/neutrinos-not-faster-than-light-1...
Although it seems like the gp misread decay.
Although it seems like the gp misread decay.
Tesla was right.
just for the record and to please the prospective downvoting mob, in order to warn any non-westerners:
"The cost [...] has been evaluated, taking into account realistic labor prices in different countries. The total cost is X (with a western equivalent value of Y) [where Y>X]
source: LHCb calorimeters : Technical Design Report
ISBN: 9290831693 http://cdsweb.cern.ch/record/494264
http://cdsweb.cern.ch/record/1127343?ln=en
"The cost [...] has been evaluated, taking into account realistic labor prices in different countries. The total cost is X (with a western equivalent value of Y) [where Y>X]
source: LHCb calorimeters : Technical Design Report
ISBN: 9290831693 http://cdsweb.cern.ch/record/494264
http://cdsweb.cern.ch/record/1127343?ln=en
I've gotta say, you sound sort of like you think you have a point and that you think it might be controversial, but I have no idea what it might be.
Search for any post about CERN, and you'll find his posts like the above.
From what I can tell, he's claiming that CERN discriminates against non-Western people. His evidence is a budget report, where they estimate how much something will cost based on the amount of people involved. The calculation adjusts for where the people are located, and the cost is higher if they're in a Western country.
From what I can tell, he's claiming that CERN discriminates against non-Western people. His evidence is a budget report, where they estimate how much something will cost based on the amount of people involved. The calculation adjusts for where the people are located, and the cost is higher if they're in a Western country.
There are Japanese and Indians who work for CERN, so I think hes just trolling.
Japan and India (China, Russia, Brazil) are not CERN member states.
But there are Eastern European, CERN member states. Some from there work for CERN, in Switzerland.
Do not think, that value as in monetary value just stays in a spreadsheet cell at HR. The evaluation has consequences in all other evaluations, peer evaluations etc. It does contribute to the evaluation of contributions etc.
But there are Eastern European, CERN member states. Some from there work for CERN, in Switzerland.
Do not think, that value as in monetary value just stays in a spreadsheet cell at HR. The evaluation has consequences in all other evaluations, peer evaluations etc. It does contribute to the evaluation of contributions etc.
Not the first time I've seen HN mangle post relations - he (or she) probably either posted to the wrong thread or some bits went to the left when they should have gone to the right.
http://www.science20.com/quantum_diaries_survivor/lhcb_evide...
From the sound of it, many of the details won't become available until a seminar tomorrow. (Nevertheless, it sounds like this really will constrain many forms of "new physics" by quite a bit.)