Mini Big-Bang at LHC

ihavequestions

http://www.bbc.co.uk/news/science-environment-11711228

How exciting!

ihavequestions

ihavequestions wrote: »

http://www.bbc.co.uk/news/science-environment-11711228

How exciting!

Interesting, thanks for the link.

heres the inevitable webcam LOL

http://www.cyriak.co.uk/lhc/lhc-webcams.html

rccaulfield

Thats huge! Can't wait for the data to be analyzed-hopefully we can find something new!:D I still struggle to understand how 10 trillion degree experiments can be safe though?

dlofnep

Insane. I find the LHC very frightening on a personal note. Probably out of ignorance, but that doesn't qualm my fears nonetheless.

Johnmb

dlofnep wrote: »

Insane. I find the LHC very frightening on a personal note. Probably out of ignorance, but that doesn't qualm my fears nonetheless.

Don't worry about it, if the worst case scenario that some people claimed could happen actually were to happen, it'd be over so fast you wouldn't even know it had happened! Plus, in reality, the worst case scenario that could happen would be localised to the Swiss-French border, we'd just hear the bang and fell the vibrations.....

thebouldwhacker

Its a shame that it didn't get a bit more coverage, I guess the meaning of life, the universe and everything just isnt as interesting as a Tesco check out lady singing......:rolleyes:

WalterMitty

this phenomenon occurs all the time high in the atmosphere where cosmic rays strike atoms/molecules i beleive. Its just first time it can be observed in a controlled environment.

rccaulfield

thebouldwhacker wrote: »

Its a shame that it didn't get a bit more coverage, I guess the meaning of life, the universe and everything just isnt as interesting as a Tesco check out lady singing......:rolleyes:

:D:D

stevoslice

LHC Creates Cosmic Primordial Soup and Probes Strange Particle Jets/

Now that the Large Hadron Collider is smashing lead, the discoveries are coming fast and furious.

Earlier this month CERN’s smashing machine switched from sending protons zinging around its ring to sending heavy lead ions at relativistic speeds. Those energetic collisions, the physicists now say, have allowed them to use the LHC’s ALICE experiment to glimpse quark-gluon plasma, the “primordial soup” present just after the Big Bang.

During this time, the Universe would have been so hot and energetic that the particles making up the elements we know today were unable to form, leaving the constituents to float “free” as a primordial soup. Quarks and gluons were only able to condense into larger particles when universal energy conditions were low enough. Hadrons (i.e. particles made from quarks; including baryons like neutrons and protons) were only allowed to form 10-6 seconds after the Big Bang. [Discovery News]


In addition to creating the plasma, the CERN experiments have also shown they have the ability to probe the jets of particles that stream away from an energetic collision, and those jets could hold hints about the beginnings of the universe.

Jets are a common sight in collisions of protons at the LHC, usually appearing in pairs as narrow cones of particles heading away in opposite directions from the collision point. They are equally common in collisions of lead ions, but with a twist. The ATLAS measurement showed that the more “head-on” the collisions of lead ions, the more unbalanced the energies of the jets streaming out in opposite directions from the collision point. While one jet may still appear as a narrow cone of particles, the second jet has a much lower energy, and the narrow cone of particles has become much more diffused.


That effect is called “jet quenching,” and the imbalance appears when one jet must travel through more quark-gluon plasma to escape the collision area than the other:

If the collision happens near the edge of the soup, one quark only has to pass through a bit of soup to escape – that’s the big jet. But the other, going in the opposite direction, has to travel through lots of hot dense exotic matter. It gets scattered around and loses lots of energy into the medium it is passing through. That’s the “missing” second jet. [The Guardian]


Jet quenching was indirectly observed at Brookhaven National Lab seven years ago. But with the energies at LHC, the effect is so pronounced that physicists could see it directly. Seeing it directly could tell them more about how particles diffuse in the quark-gluon plasma, and thus, more about what the first tiny fraction of a second of the universe’s life was like.

The jet quenching find from LHC’s ATLAS detector will appear in Physics Review Letters, but for now you can read it on CERN’s website.

stevoslice

Anyone else keeping track of this.

LHC's Lack of Black Holes Rules out Some Versions of String Theory

You know those black holes the Large Hadron Collider was going to make and kill us all? Well, not only are we still here, but the LHC doesn’t seem to be making black holes at all—their decay signature is markedly absent from the data collected so far.

While that is good for those of us who want to keep living (we jest—the hypothetical micro black holes posed no danger), it’s also helping physicists make up their minds about how many dimensions there are in our universe. The lack of black holes at the LHC nullifies some of the wackier versions of string theory which depend on multiple dimensions.

“In order for the LHC to produce some of these black holes, we really have to go beyond the normal theory of gravity,” [CERN theoretical physicist Michelangelo Mangano] said [two years ago]. “We have to assume that there are extra dimensions. By the way, there are many theories that have extra dimensions. Not all of them would give rise to black holes at the LHC. It’s only highly fine-tuned ones that make this possible.” [CosmicLog]

These extra dimensions, beyond the four that we experience, are needed to rectify the inconsistencies between general relativity (the physics of gravity and space-time) and quantum mechanics (the physics of subatomic particles). Some string theories predict that gravity is stronger in these other dimensions, and that at very small distances (where these dimensions are experienced), it would be strong enough to create a black hole.

Since the scientists haven’t seen the signals that these black holes would make, it’s likely that this particular flavor of string theory isn’t correct. The data will be published in Physics Letters, and is currently available on arXiv.