Unexpected LHC Results Summary

  • Thread starter kye
  • Start date
  • Tags
    lhc
  • #1
kye
168
2
Is there a list for all unexpected LHC results from the start of operation that cant be explained by the standard model? Two years ago I remembered a result where they encountered unexpected macroscopic superposition akin to superconductivity.. where the particles dance together... anyone remember it? how do they explain it? Please share all weird results from the beginning of operation.
 

Answers and Replies

  • #2
Vanadium 50
Staff Emeritus
Science Advisor
Education Advisor
2019 Award
25,643
8,830
Yes, and here is that list:
 
  • #3
kye
168
2
  • #4
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
787
He actually wrote down the list, Kye.
 
  • #5
kye
168
2
He actually wrote down the list, Kye.
Maybe you saw it in your PF external software, but it didn't appear in the public site see message # 2 https://www.physicsforums.com/showthread.php?t=725134

The LHC will be online 2015 and we will miss it for 2 years so it's good to check the complete unexpected things it has discovered..
 
  • #6
George Jones
Staff Emeritus
Science Advisor
Gold Member
7,392
1,019
He actually wrote down the list, Kye.
i.e, the list is the empty set, since the LHC has (yet) to produce any unexpected results.
 
  • #7
berkeman
Mentor
58,370
8,443
:rofl:
 
  • #8
kye
168
2
i.e, the list is the empty set, since the LHC has (yet) to produce any unexpected results.
I read an LHC result in the news about two years ago where the showers of particles have macroscopic coherence.. and they are surprised about it.. if anyone has encountered it, please share it.. i'll look for old archives...
 
  • #10
kye
168
2
http://en.ria.ru/science/20100922/160675724.html

I found it after 40 minutes of searching at google. What do you guys think of the above?

""Physicists conducting experiments on the world's largest atom smasher
have discovered a new phenomenon in proton interactions that may change
our view of the Standard Model of particle physics.

A study of "high multiplicity" collisions, where a hundred or more
charged particles are produced, has revealed indications that some
particles are somehow "correlated" or associated together when they were
created at the point of collision."
 
  • #11
fzero
Science Advisor
Homework Helper
Gold Member
3,119
289
http://en.ria.ru/science/20100922/160675724.html

I found it after 40 minutes of searching at google. What do you guys think of the above?

""Physicists conducting experiments on the world's largest atom smasher
have discovered a new phenomenon in proton interactions that may change
our view of the Standard Model of particle physics.

A study of "high multiplicity" collisions, where a hundred or more
charged particles are produced, has revealed indications that some
particles are somehow "correlated" or associated together when they were
created at the point of collision."
That article is short on details, so we can't be sure what is actually being referred to. But correlations between particles produced at a collider are by no means a sign of new physics. Whenever we have conservation laws (momentum, angular momentum, charge, etc), there will be correlations between the final state particles corresponding to the conservation of these quantities. As a simple example, suppose we collide an electron of momentum ##\vec{p}## with a positron with momentum ##-\vec{p}## to produce a proton and an antiproton. If we measure the proton to have momentum ##\vec{k}##, then momentum conservation dictates that the antiproton has momentum ##-\vec{k}##. In the language of quantum mechanics we can describe these correlations using entangled states if we want to.

From googling the physicist Vladimir Gavrilov referred to in the article, I suspect that he is referring to something called color coherence. This is something that is theoretically predicted and described in standard references like this one.
 
  • #12
kye
168
2
That article is short on details, so we can't be sure what is actually being referred to. But correlations between particles produced at a collider are by no means a sign of new physics. Whenever we have conservation laws (momentum, angular momentum, charge, etc), there will be correlations between the final state particles corresponding to the conservation of these quantities. As a simple example, suppose we collide an electron of momentum ##\vec{p}## with a positron with momentum ##-\vec{p}## to produce a proton and an antiproton. If we measure the proton to have momentum ##\vec{k}##, then momentum conservation dictates that the antiproton has momentum ##-\vec{k}##. In the language of quantum mechanics we can describe these correlations using entangled states if we want to.

From googling the physicist Vladimir Gavrilov referred to in the article, I suspect that he is referring to something called color coherence. This is something that is theoretically predicted and described in standard references like this one.
why did the article mentioned this?

""This is a phenomenon that has not been predicted by theoretical calculations," Gavrilov said."

maybe the "not" is a typo or maybe the russian physicist didnt know the meaning of color coherence? or maybe the article misreporting. hope other russians can shed light on this
 
Last edited by a moderator:
  • #13
atyy
Science Advisor
14,064
2,366
That article is short on details, so we can't be sure what is actually being referred to. But correlations between particles produced at a collider are by no means a sign of new physics. Whenever we have conservation laws (momentum, angular momentum, charge, etc), there will be correlations between the final state particles corresponding to the conservation of these quantities. As a simple example, suppose we collide an electron of momentum ##\vec{p}## with a positron with momentum ##-\vec{p}## to produce a proton and an antiproton. If we measure the proton to have momentum ##\vec{k}##, then momentum conservation dictates that the antiproton has momentum ##-\vec{k}##. In the language of quantum mechanics we can describe these correlations using entangled states if we want to.

From googling the physicist Vladimir Gavrilov referred to in the article, I suspect that he is referring to something called color coherence. This is something that is theoretically predicted and described in standard references like this one.
Maybe http://cms.web.cern.ch/news/new-two-particle-correlations-observed-cms-detector-lhc ?
"The CMS Collaboration at CERN released today a paper entitled "Observation of Long-Range Near-Side Angular Correlations in Proton-Proton Collisions" that details signs of a new phenomenon in proton interactions."

http://arxiv.org/abs/1206.0148
"However, what is novel about the ridge in high multiplicity pp is that particles are produced in a correlated fashion not only over long range in rapidity but also collimated in azimuthal angle (near-side). This peculiar new feature was not observed before in pp or ppbar, or any theoretical modelings of pp collisions. The microscopic dynamics of high multiplicity particle production and near-side ridge correlations in pp have not been fully understood yet."

http://arxiv.org/abs/1311.1429
"While in the meantime far eclipsed by the discovery of ’a Higgs-like particle’, this ’near side ridge’ is arguably still the most unexpected LHC discovery to date and spawned a large variety of different explanations, from mildly speculative to outright weird [48]. The most serious contenders are saturation physics, as formulated in the Color Glass Condensate model (CGC), and collective hydrodynamic flow."
 
Last edited:
  • #14
kye
168
2
Maybe http://cms.web.cern.ch/news/new-two-particle-correlations-observed-cms-detector-lhc ?
"The CMS Collaboration at CERN released today a paper entitled "Observation of Long-Range Near-Side Angular Correlations in Proton-Proton Collisions" that details signs of a new phenomenon in proton interactions."

http://arxiv.org/abs/1206.0148
"However, what is novel about the ridge in high multiplicity pp is that particles are produced in a correlated fashion not only over long range in rapidity but also collimated in azimuthal angle (near-side). This peculiar new feature was not observed before in pp or ppbar, or any theoretical modelings of pp collisions. The microscopic dynamics of high multiplicity particle production and near-side ridge correlations in pp have not been fully understood yet."

http://arxiv.org/abs/1311.1429
"While in the meantime far eclipsed by the discovery of ’a Higgs-like particle’, this ’near side ridge’ is arguably still the most unexpected LHC discovery to date and spawned a large variety of different explanations, from mildly speculative to outright weird [48]. The most serious contenders are saturation physics, as formulated in the Color Glass Condensate model (CGC), and collective hydrodynamic flow."
Thanks for the links. I spent several hours reading and analyzing them and finally understood what's it saying after checking many links (recommended for newbies those who want to get the essence of it all) especially:

http://en.wikipedia.org/wiki/Color_glass_condensate

http://www.huffingtonpost.com/2012/...e-large-hadron-collider-matter_n_2199988.html

"Somehow they fly at the same direction even though it's not clear how they can communicate their direction with one another. That has surprised many people, including us," MIT physicist Gunther Roland, whose group led the analysis of the collision data along with Wei Liof Rice University, said in a statement.

A similar flight pattern is seen when two heavy particles, such as lead and lead, crash into each other. In this case, the collisions create what's called quark-gluon plasma — a superhot soup of particles similar to the state of the universe just after the Big Bang. This soup can sweep particles in the same direction, explaining why their flight directions would be correlated.

But quark-gluon plasma isn't possible with lead-proton collisions, like the ones in the new study. Now researchers think a different state of matter, the color-glass condensate, may act in a similar way. The color-glass condensate's dense swarm of gluons may also sweep particles off in the same direction, suggested Brookhaven National Laboratory physicistRajuVenugopalan, who first predicted the substance, which may also be seen after proton-proton collisions."

==================

So maybe color-glass condensate is the answer? For those who still think about entanglement, just imagine the particles not moving away from each other with correlations in the spin or momentum, but in direction which is not possible if just pure quantum (?) that's why they have to propose new state of matter of even collective hydrodynamic flow (what is the ramification of this?). If it's just plain color-glass condensate, would this change anything in search of new physics beyond the standard model or just nothing?
 
  • #15
980
2
Anything to do with heavy ions should keep in mind the difference between new "fundamental" physics, and new physics at the level of QCD with a condensed matter flavour. QCD interactions with that many particles is pushing the theory into less well-studied phases, and one should not be too surprised that new phenomenon emerge which require more theoretical study. However, this is going to be confined within the existing framework of the Standard Model, rather than pointing at some fundamental violation of it.
 

Related Threads on Unexpected LHC Results Summary

Replies
1
Views
6K
Replies
2
Views
780
Replies
11
Views
2K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
11
Views
3K
Replies
13
Views
3K
  • Last Post
Replies
17
Views
4K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
6
Views
5K
Top