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Things I didn't get from article: What changed to make a slew of new discoveries possible? Is it pure chance like Bitcoin mining? If so, what's the chance of d

Things I didn't get from article: What changed to make a slew of new discoveries possible? Is it pure chance like Bitcoin mining? If so, what's the chance of discovering nothing for years and then, like London buses, three all come along at once? What are the implications of a new "particle zoo"? Can I do anything with these, like build new atoms, or use them to detect something?

adregan 4y ago
I believe it’s due to the fact that after several years of upgrades, they started running it today at much higher power (13.6 trillion electronvolts).
- Quinner 4y ago
  They would definitely not be publishing results of the power increase on the same day of the increase. These experiments take a lot more time than a day to perform and analyse.
  - swader999 4y ago
    Or time travel. That's a lot of power they just added.
  - deleted 4y ago
    [deleted]
stevenwoo 4y ago
There's another article floating about how they increased energy of collisions recently at LHC. https://www.nature.com/articles/d41586-022-01388-6 https://www.nature.com/articles/d41586-022-01388-6
- dicknuckle 4y ago
  Fairly sure this was scheduled to happen today, July 5th.
chicX 4y ago
The change is the gradual accumulation of statistics. These are relatively rare events. The LHC has been running, high-energy proton-proton collisions have been occurring, and the LHCb detector in this case has been measuring them. The statistics increase, and eventually the characteristic peaks of short-lived resonances can be identified above the noise of "background" collisions. I think the goal of this work is to understand the nature of the strong force. Quantum chromodynamics (QCD) is pretty difficult as far as quantum field theories go, its strongly-coupled, meaning making first-principles predictions of what to expect is really tough. Its a huge computational effort being run on some of the biggest computers on the planet (lattice QCD). We observe that all the hadrons in experiment are "colour singlets" meaning that the colour charge of QCD is hidden. These are usually three-quark states (protons, neutrons, etc) or quark-antiquark states (pions, kaons, etc). There are many other ways of making "colour singlets". For example, these tetra and pentaquark combinations. There are also "hybrids" made of a gluon and some combination of quarks. There is some evidence on both experimental and theoretical sides for at least a few of these hybrids. Glueballs are also possible, states made entirely of gluons, but there is only really theoretical evidence for these so far in specific limits. We just don't know if they exist in reality. Everything is made of this stuff. Most of the mass around us comes from the strong interactions. It's important to understand it.
- parineum 4y ago
  > The change is the gradual accumulation of statistics. These are relatively rare events. The LHC has been running, high-energy proton-proton collisions have been occurring, and the LHCb detector in this case has been measuring them. The statistics increase, and eventually the characteristic peaks of short-lived resonances can be identified above the noise of "background" collisions. I think people are a bit spoiled by the Higgs leak/announcement/discovery timeline. I'm sure those in the know have known about this discovery for some time but, like you said, it takes some time to gather enough data to be confident (and to qualify as the mathematical standard set for "discovery").
  - ncmncm 4y ago
    Right, after the bump reaches 3x sigma they have some confidence it deserves their own attention, and at 4x they are sure, but the rule is you don't publish until you have enough data for a 5x sigma result, which just takes a lot more data and a lot longer. "Sigma" here refers to standard deviations off the Gaussian normal mean. Zero means completely random. In psychology they publish at 2x sigma, 95%, which means 20:1 odds against a spurious result, and they publish a lot of spurious results because you can generate an unlimited number of hypotheses. In physics, things are considered more deterministic, and an experiment doesn't need to recruit undergrads to be data points, so you run your LHC for a few more months and avoid wasting people's attention.
hypertele-Xii 4y ago
Think of it like taking series of blurry photos of an unknown object. A single photo just looks like a blob, but accumulate enough of them and apply some algorithmic magic and eventually the picture sharpens. When particles are collided and the result measured, there's probably lots of noise in the data. In a single picture, a single pixel (datapoint) tells you nothing. But capture enough results, and you can begin to filter the noise out, revealing patterns underneath.
legohead 4y ago
Cool results considering the recent article I saw on HN suggesting there's not much else to find [1]. [1] https://bigthink.com/hard-science/large-hadron-collider-economics/ https://bigthink.com/hard-science/large-hadron-collider-econ...
- byecomputer 4y ago
  today's particle drop is dedicated to the haters
davrosthedalek 4y ago
They came together most likely because they were detected in the same/similar analysis. There are probably hundreds of analysis performed in parallel on the LHCb data sets, by different sub-groups of the collaboration, looking at different reactions / channels etc. It could also be that they grouped several results together because they are similar. There is always an internal review process, and committee meetings (for the final "go ahead, publish") can impose a granularity on the time of release. Could also be that the paper is already on the arXiv for days, and this is just the common press release.
letmeoknmmm 4y ago
> If so, what's the chance of discovering nothing for years and then, like London buses, three all come along at once? Means we are in a pretty tricky timeline.
pishpash 4y ago
Just a few days ago weren't people saying nothing was discovered since the Higgs boson and it was a waste of money?
- maxnoe 4y ago
  No new elementary particles. These newly discovered particles are composed of multiple quarks and were found (at least up to the measurement precision) with the expected rules of how you can combine the elementary particles into composed particles (Baryons in thos case). LHCb actually discovered a bunch of those in the last couple of years. But these are expected from the standard model, just rare and thus not experimentally confirmed before. "Nothing new" for LHC means no new physics. And if these quark states don't happen to be much more frequent or much more rare than predicted, there is no new physics here.
maxnoe 4y ago
> If so, what's the chance of discovering nothing for years and then, like London buses, three all come along at once? First, there was a pretty constant stream of these kinds of discoveries over the last years. Most of them even discussed here [1, 2, 3 and more] Second, what you need to find these rare events are two things: enough statistics and someone actually doing a specialized analysis looking for them. Enough statistics have been accumulating over the past years, and now someone stepped forward, developed the analysis, tested it on small scale dataset, got it approved by the Collaboration, ran it on the large dataset and then chances are that you don't just find one but three very similar things. Disclaimer: I am not part of LHCb and have no insight into the specific analysis of this discovery, just sitting on the same floor as the LHCb guys and knowing the general procedure. Third, as noted in a sister comment, these quark states are expected from the standard model, they are just very rare and very short lived, so hard to find. Nothing new normally refers to "no physics found incompatible with the standard model". [1] https://home.cern/news/news/physics/lhcb-experiment-discovers-new-pentaquark https://home.cern/news/news/physics/lhcb-experiment-discover... [2] https://cerncourier.com/a/new-pentaquarks-resolved-by-lhcb/ https://cerncourier.com/a/new-pentaquarks-resolved-by-lhcb/ [3] https://physicsworld.com/a/lhcb-bags-another-pentaquark/ https://physicsworld.com/a/lhcb-bags-another-pentaquark/

adregan 4y ago

I believe it’s due to the fact that after several years of upgrades, they started running it today at much higher power (13.6 trillion electronvolts).

Quinner 4y ago
They would definitely not be publishing results of the power increase on the same day of the increase. These experiments take a lot more time than a day to perform and analyse.
- swader999 4y ago
  Or time travel. That's a lot of power they just added.
- deleted 4y ago
  [deleted]

stevenwoo 4y ago

There's another article floating about how they increased energy of collisions recently at LHC. https://www.nature.com/articles/d41586-022-01388-6 https://www.nature.com/articles/d41586-022-01388-6

dicknuckle 4y ago
Fairly sure this was scheduled to happen today, July 5th.

chicX 4y ago

The change is the gradual accumulation of statistics. These are relatively rare events. The LHC has been running, high-energy proton-proton collisions have been occurring, and the LHCb detector in this case has been measuring them. The statistics increase, and eventually the characteristic peaks of short-lived resonances can be identified above the noise of "background" collisions. I think the goal of this work is to understand the nature of the strong force. Quantum chromodynamics (QCD) is pretty difficult as far as quantum field theories go, its strongly-coupled, meaning making first-principles predictions of what to expect is really tough. Its a huge computational effort being run on some of the biggest computers on the planet (lattice QCD). We observe that all the hadrons in experiment are "colour singlets" meaning that the colour charge of QCD is hidden. These are usually three-quark states (protons, neutrons, etc) or quark-antiquark states (pions, kaons, etc). There are many other ways of making "colour singlets". For example, these tetra and pentaquark combinations. There are also "hybrids" made of a gluon and some combination of quarks. There is some evidence on both experimental and theoretical sides for at least a few of these hybrids. Glueballs are also possible, states made entirely of gluons, but there is only really theoretical evidence for these so far in specific limits. We just don't know if they exist in reality. Everything is made of this stuff. Most of the mass around us comes from the strong interactions. It's important to understand it.

parineum 4y ago
> The change is the gradual accumulation of statistics. These are relatively rare events. The LHC has been running, high-energy proton-proton collisions have been occurring, and the LHCb detector in this case has been measuring them. The statistics increase, and eventually the characteristic peaks of short-lived resonances can be identified above the noise of "background" collisions. I think people are a bit spoiled by the Higgs leak/announcement/discovery timeline. I'm sure those in the know have known about this discovery for some time but, like you said, it takes some time to gather enough data to be confident (and to qualify as the mathematical standard set for "discovery").
- ncmncm 4y ago
  Right, after the bump reaches 3x sigma they have some confidence it deserves their own attention, and at 4x they are sure, but the rule is you don't publish until you have enough data for a 5x sigma result, which just takes a lot more data and a lot longer. "Sigma" here refers to standard deviations off the Gaussian normal mean. Zero means completely random. In psychology they publish at 2x sigma, 95%, which means 20:1 odds against a spurious result, and they publish a lot of spurious results because you can generate an unlimited number of hypotheses. In physics, things are considered more deterministic, and an experiment doesn't need to recruit undergrads to be data points, so you run your LHC for a few more months and avoid wasting people's attention.

hypertele-Xii 4y ago

Think of it like taking series of blurry photos of an unknown object. A single photo just looks like a blob, but accumulate enough of them and apply some algorithmic magic and eventually the picture sharpens. When particles are collided and the result measured, there's probably lots of noise in the data. In a single picture, a single pixel (datapoint) tells you nothing. But capture enough results, and you can begin to filter the noise out, revealing patterns underneath.

legohead 4y ago

Cool results considering the recent article I saw on HN suggesting there's not much else to find [1]. [1] https://bigthink.com/hard-science/large-hadron-collider-economics/ https://bigthink.com/hard-science/large-hadron-collider-econ...

byecomputer 4y ago
today's particle drop is dedicated to the haters

davrosthedalek 4y ago

They came together most likely because they were detected in the same/similar analysis. There are probably hundreds of analysis performed in parallel on the LHCb data sets, by different sub-groups of the collaboration, looking at different reactions / channels etc. It could also be that they grouped several results together because they are similar. There is always an internal review process, and committee meetings (for the final "go ahead, publish") can impose a granularity on the time of release. Could also be that the paper is already on the arXiv for days, and this is just the common press release.

letmeoknmmm 4y ago

> If so, what's the chance of discovering nothing for years and then, like London buses, three all come along at once? Means we are in a pretty tricky timeline.

pishpash 4y ago

Just a few days ago weren't people saying nothing was discovered since the Higgs boson and it was a waste of money?

maxnoe 4y ago
No new elementary particles. These newly discovered particles are composed of multiple quarks and were found (at least up to the measurement precision) with the expected rules of how you can combine the elementary particles into composed particles (Baryons in thos case). LHCb actually discovered a bunch of those in the last couple of years. But these are expected from the standard model, just rare and thus not experimentally confirmed before. "Nothing new" for LHC means no new physics. And if these quark states don't happen to be much more frequent or much more rare than predicted, there is no new physics here.

maxnoe 4y ago

> If so, what's the chance of discovering nothing for years and then, like London buses, three all come along at once? First, there was a pretty constant stream of these kinds of discoveries over the last years. Most of them even discussed here [1, 2, 3 and more] Second, what you need to find these rare events are two things: enough statistics and someone actually doing a specialized analysis looking for them. Enough statistics have been accumulating over the past years, and now someone stepped forward, developed the analysis, tested it on small scale dataset, got it approved by the Collaboration, ran it on the large dataset and then chances are that you don't just find one but three very similar things. Disclaimer: I am not part of LHCb and have no insight into the specific analysis of this discovery, just sitting on the same floor as the LHCb guys and knowing the general procedure. Third, as noted in a sister comment, these quark states are expected from the standard model, they are just very rare and very short lived, so hard to find. Nothing new normally refers to "no physics found incompatible with the standard model". [1] https://home.cern/news/news/physics/lhcb-experiment-discovers-new-pentaquark https://home.cern/news/news/physics/lhcb-experiment-discover... [2] https://cerncourier.com/a/new-pentaquarks-resolved-by-lhcb/ https://cerncourier.com/a/new-pentaquarks-resolved-by-lhcb/ [3] https://physicsworld.com/a/lhcb-bags-another-pentaquark/ https://physicsworld.com/a/lhcb-bags-another-pentaquark/