A step closer to Big Bang conditions? More study is needed to confirm the latest LHC findings

Sep 29, 2010 Anne Trafton, MIT News
Proton-proton collisions at the Large Hadron Collider produce hundreds of particles. Some of those particles form pairs that display an unexpected correlation. Image: CERN

Since December, the Large Hadron Collider (LHC) has been smashing particles together at record-setting energy levels. Physicists hope that those high-energy collisions could replicate the conditions seen immediately after the Big Bang, shedding light on how our universe came to be. Now, data from collisions that took place in July suggests that the LHC may have have taken a step toward that goal.

The finding, which has been submitted to the Journal of High Energy Physics, comes from proton-proton collisions that occurred in the LHC in July, each of which produced 100 or more charged particles. One of the two large, general-purpose detectors at LHC, the Compact Muon Solenoid (CMS) experiment, measured the path that each of these particles took after the collision.

The CMS observed a surprising new phenomenon in some pairs of those particles: They appeared to be associated together at the point of collision. That is, when some pairs of particles fly away from each other after the collision, their respective directions appear to be correlated. Such correlations between particles that move away from each other at near the speed of light had not been seen before in collisions of .

“As soon as the measurement came out — first within the experiment and then presented publicly — there was a lot of debate about the possible explanation,” says Gunther Roland, a physicist in the MIT heavy-ion group who was one of the leaders of  the analysis of the data along with MIT postdoctoral associate Wei Li.

Some of the proposed explanations are based on subtle effects in the scattering of the that make up the colliding protons, which may not be described by current models of these interactions. Others assume that the effect is the result of the high density of particles in the early stages of the , says Roland, an associate professor of physics at MIT.

At the at Brookhaven National Laboratory, physicists have observed similar phenomena following collisions of heavier particles such as copper and gold ions. One explanation for the observation at Brookhaven is that the quarks and gluons were forced together at such high densities that they were freed, becoming quark-gluon plasma — the hot soup of elementary particles that existed for a few millionths of a second after the Big Bang and that subsequently cooled and formed protons and neutrons, the building blocks of matter.

In the upcoming months, physicists plan to increase the intensity of LHC proton beams, providing at least 100 times more data that can be used to further study this phenomenon. They also plan to run beams of heavier ions, such as lead. Based on these studies, it will be possible to eliminate many of the proposed explanations and  to study if the effects in proton-proton and heavy ion collisions are related.


This story is republished courtesy of MIT News (web.mit.edu/newsoffice/), a popular site that covers news about MIT research, innovation and teaching.

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User comments : 16

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savroD
1.9 / 5 (7) Sep 29, 2010
You know....
They keep saying these conditions are close to that of the Big Bang. It seems to me that these conditions are occurring constantly in space. It would probably be a lot cheaper to build a large detector in space; however, the bigger point is that Big Bang, (which I'm not buying), is happening now folks. The universe doesn't perceive time as humans do. It seems to me that time does not exist other than as a tool of scientific measuremnt. The fourth dimension is not time, nor space-time. It is.....
I'll save that for my paper!
PieRSquare
5 / 5 (4) Sep 29, 2010
The fourth dimension is not time, nor space-time. It is.....

Tea-time?
Miller-time?
Hammer-time?
krundoloss
not rated yet Sep 29, 2010
If dimensions are used to describe matter, then time would have to be a dimension as an object must exist in at a particular time. It could be a construct, though, it always seemed weird that time was the fourth dimension. Maybe gravity is the 5th dimension?
Quantum_Conundrum
1 / 5 (1) Sep 29, 2010
Krundoloss:

Time is probably more correctly labelled as the first dimension.
BillFox
not rated yet Sep 29, 2010
Krundoloss:

Time is probably more correctly labelled as the first dimension.


If that were the case, at least you can tell us how long you have been living in your flat world.
TheQuietMan
not rated yet Sep 29, 2010
The comment about space having similar conditions pop up is probably correct, but they do not occur on demand in any place we can reach, so the suggestions of detectors in space is pretty silly. Better to do it where we can setup the really sensitive local instrumentation.

It is amazing how many people claim knowledge while spouting these incredibly dumb ideas.
droid001
5 / 5 (2) Sep 29, 2010
When we watching a movie, it seems that there is time in the movie.
However, movie have no time, just data.
PhysicsLver21
1 / 5 (5) Sep 29, 2010
When we watching a movie, it seems that there is time in the movie.
However, movie have no time, just data.


...? Go learn so grammar first before posting on this site.
trekgeek1
5 / 5 (5) Sep 29, 2010
When we watching a movie, it seems that there is time in the movie.
However, movie have no time, just data.


...? Go learn so grammar first before posting on this site.


Are you sure that English is their first language? They may not know the language well but were brave enough to try so that they could share their ideas. Don't criticize unless you have all the facts, it's just rude.
frajo
5 / 5 (4) Sep 30, 2010
When we watching a movie, it seems that there is time in the movie.
However, movie have no time, just data.
...? Go learn so grammar first before posting on this site.
Apropos English language: What's that "so" supposed to mean?
HeloMenelo
1 / 5 (2) Oct 03, 2010
"Hammer-time?"

Can't touch this...
Objectivist
not rated yet Oct 03, 2010
Krundoloss:

Time is probably more correctly labelled as the first dimension.

I think time always has to be the last dimension depending on which dimensions you govern. In our case we govern the 3 spatial dimensions and perceive the fourth as change, or the outcome of the collapsed wave functions of ourselves and our surroundings. If you would however find yourself in the fifth dimension, meaning you govern the four lower dimensions, you would be able to observe what we consider time as static. You would see the birth and death of our universe at the same time. What you would perceive as time would be change to any of the possible outcomes in the any given moment within the universe. The change (or time) you would see would be e.g. how a child grows up to be a doctor, and that same child growing up to be a lawyer as you travel along the fifth dimension, but no matter which one of these possible outcomes you're observing you would see this persons entire life at once.
RobertT
not rated yet Oct 03, 2010
Before we even begin to question what is which dimension, maybe we should ask ourselves why the dimensions are in order? 1st, 2nd, 3rd, 4th.... 11th?

What is "higher" dimension? why can't time be the highest dimension? Heck, why can't our spatial dimensions be considered as the "highest" in our universe?
sleepaholic
not rated yet Oct 04, 2010
So did they find any tiny particles that have not been known before, yet?
Skeptic_Heretic
3 / 5 (2) Oct 04, 2010
Before we even begin to question what is which dimension, maybe we should ask ourselves why the dimensions are in order? 1st, 2nd, 3rd, 4th.... 11th?

What is "higher" dimension? why can't time be the highest dimension? Heck, why can't our spatial dimensions be considered as the "highest" in our universe?

How would you order the dimensions without first kowing what they're composed of or how they came to be? The dimensions simply are, there is no particular order as far as we can tell.

Objectivist
5 / 5 (2) Oct 04, 2010
... maybe we should ask ourselves why the dimensions are in order? 1st, 2nd, 3rd, 4th.... 11th

This shows you haven't really looked into the matter at all. It's a shame because the basics are really simple to understand. A dimension is just a mathematical angle of freedom, and the sequence follow a consecutive order. Point to plane to cube etc. You can't go from point to cube without passing plane. Meaning you can't go from X to XYZ without passing XY. It's basic geometry until you get to the 4th dimension. Even then the concept isn't too strange to understand. Time is an angle of freedom that we move in. We don't govern it and thus we can only travel through it in one way. Think of it as our 3D being a bubble traveling through a big 4D space, and as we go from point A to point B (we have no other choice) we experience different 3D projections of the outside 4D world. If you google "flatlander" you'll find a simple explanation for the latter.

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