Predicted experimental test will clarify how light interacts with matter at high energies

Aug 02, 2013
Figure 1: The uneven shape of a quark–gluon plasma. The arrows indicate the directions and momentums of particles produced by atomic collisions. Credit: 2013 Adam Bzdak and Vladimir Skokov, RIKEN BNL Research Center

Collisions of atomic and subatomic particles at very high energies reveal important properties about the beginning of the Universe and the atomic forces, and how fundamental particles are formed and react with each other. Adam Bzdak from the RIKEN BNL Research Center and colleague Vladimir Skokov from Brookhaven National Laboratory in the US have now proposed a scheme that allows for a better understanding of how light and subatomic particles react with each other during such high-energy collisions.

At the very early stages of the Universe there were no atoms: energies were so high that atoms would have been torn apart. Instead, there was a mix of such as and quarks. These make up the protons and neutrons inside atomic cores, but at very high energies they form a hot cloud known as a quark–gluon plasma. These plasmas can also be produced artificially by smashing heavy atoms together, as is currently being performed by the PHENIX Collaboration at the Relativistic Heavy Ion Collider at Brookhaven.

In these experiments, it has been observed that light (photons) emanating from the collision zone varies in intensity depending on the direction of (Fig. 1). This uneven distribution of photons is similar to the pattern expected for a quark–gluon plasma, which has surprised scientists. "Photons do not interact with the created matter and cannot be sensitive to the shape of the fireball," says Bzdak. "This is a clear paradox and so far there is no compelling explanation. Clearly we do not understand something very basic."

Although several theories, such as the role of magnetic fields, have been proposed that could explain this effect, a clear explanation has not been possible. Bzdak and Skokov have now proposed a scheme that aims to identify whether magnetic fields are indeed responsible, or whether photons are simply produced non-uniformly during the collisions. Their theoretical study compares the emission patterns of photons for different shapes of the quark–gluon plasma and different numbers of particles creating magnetic fields. If the emission pattern of the photons follows that of the different quark–gluon plasma, it would verify the direct connection between the two phenomena.

The experimental verification of their proposal will be the next step, says Bzdak. "I believe our job is done and now the ball is in the experimentalists' court. The implementation of our scheme is quite straightforward and is currently being studied by the PHENIX Collaboration."

Explore further: New microscope collects dynamic images of the molecules that animate life

More information: Bzdak, A. & Skokov, V. Anisotropy of photon production: Initial eccentricity or magnetic field. Physical Review Letters 110, 192301 (2013). dx.doi.org/10.1103/PhysRevLett.110.192301

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User comments : 10

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bearly
1 / 5 (4) Aug 02, 2013
They need this information in order to calibrate their laser weapons. lol
chardo137
3 / 5 (2) Aug 02, 2013
It is really too bad that the RHIC is being shut down. It was one of the last places that the US had which was doing truly fundamental physics.
vacuum-mechanics
1 / 5 (7) Aug 02, 2013
In these experiments, it has been observed that light (photons) emanating from the collision zone varies in intensity depending on the direction of light emission (Fig. 1). This uneven distribution of photons is similar to the pattern expected for a quark–gluon plasma, which has surprised scientists. "Photons do not interact with the created matter and cannot be sensitive to the shape of the fireball," says Bzdak. "This is a clear paradox and so far there is no compelling explanation. Clearly we do not understand something very basic."

Maybe what which we believed to be created in the collision are not quark, gluon or anything at al, instead they are just the disturbed parts of vacuum (dark) energy which will disappear after the collision over…
http://www.vacuum...=9〈=en

cantueso
1 / 5 (1) Aug 08, 2013
I am not a scientist but I believe that gravity is omnipresent and is only made aware of when disturbed by mass which causes an imbalance. It is moving in every possible direction and the imbalance will follow on as gravity moves through the Universe. This theory makes the Universe expand and the centre of the Earth to be weightless. This theory also means that gravity is passing by with the effect of pushing. It may also be a carrier for light and may pick up and drop photons as it passes through any object that is able to create the pulse or wavelength that crates light and is being interfiered with even if it is just the hot gas of coliding glueons (and what is that made of). My theory, the 'Bob Sapsford theory' of how gravity works seems to me to tick a lot of boxes in a practical way. Maybe gravity is dark energy, it seems to fit the bill. Maybe I have taken a too simplistic look at it but it works for me.
DarkHorse66
1 / 5 (1) Aug 09, 2013
@cantueso. It is VERY clear that you are not a scientist. Even in high school (when physics is taught), one very quickly learns that the very source of gravity is mass itself. It does not matter whether that mass is large, eg a planet, or small ) like say, an ant. Not only does all mass produce a gravitational field, but the particular amount is directly proportional to the mass of any particular object. Even you are generating a gravitational field! Know also that an object is not required to rotate, either. That property is simply one that tends to happen to larger objects (eg a planet), that are already moving anyway. As for zero g at the centre of the earth, that is correct, but not for the reason that you think. Imagine that you are descending towards that centre via some kind of tunnel. As you are moving down, there is a thicker & thicker layer of rock between you & the surface. At the same time, there is less & rock(let's ignore the fact of heat & molten rock for this eg)..cont
DarkHorse66
1 / 5 (1) Aug 09, 2013
cont...between you & the centre. The point you need to know is this: ONLY THE GRAVITY BEING GENERATED BY THE MATTER BETWEEN YOU AND THE CENTRE IS ACTING ON YOU. The stuff above your head does not act on you. This phenomenon has nothing to with weight. (That is a separate topic.) And the closer you get to the centre, the less mass/matter there is, to generate that gravity.
http://en.wikiped...iki/Mass
http://plus.maths...ity-work (check the simple(!) equations!)
http://www.univer...me-from/
As for the rest, it is such blatant goobledegook, I'm not even going to respond to it. Not worth my time.
Regards, DH66
Gmr
2 / 5 (4) Aug 09, 2013
Don't you love how humble most radical theorists are to simply name their theories after the closest thing at hand, namely; themselves?
arenal_cantueso
not rated yet Sep 07, 2013
So dark horse what you are saying is that only matter on one side of you generates gravity,
If the mass above you dosn't count then how dose the moon work the tides?
arenal_cantueso
1 / 5 (1) Sep 07, 2013
Gmr would have prefered Einstiens theory to be called 'my cup of tea theory' or what about 'My chairs cat in the box theory'. Was that Schrodiners, I dont know, he didnt leave his name.
Gmr
1 / 5 (1) Sep 07, 2013
Gmr would have prefered Einstiens theory to be called 'my cup of tea theory' or what about 'My chairs cat in the box theory'. Was that Schrodiners, I dont know, he didnt leave his name.

He didn't call it "Einstein's Theory" either. And most scientists don't go so far as to name theories after themselves, because what is important is a cogent description of what the theory is and predicts, not who gets the credit for it. If a scientist gets something named after them, it is usually by others by way of shorthand for things like formulas, units or particles. It is called the "General Theory of Relativity" - not "Einstein's Theory." And "The Copenhagen interpretation of Quantum Mechanics" rather than "Schroedinger's Theory" - he has a cat named for him as an example of a way to magnify an atomic realm uncertainty to that of the macroscopic.