CERN experiment takes us one step closer to discovering where all the antimatter went

Jun 03, 2014
ALPHA experiment facility. Credit: CERN

New research published today by researchers from CERN has brought us a step closer to understanding where all the antimatter has gone. This matter-antimatter asymmetry is one of the greatest challenges in physics and at this moment in time the universe seems to be composed entirely of matter – the only antimatter around is created by us at places like CERN. Yet our theories predict that exactly equal amounts of matter and antimatter would have been created in the Big Bang. So where did all the antimatter go?

This new research, undertaken by the ALPHA experiment at CERN's Antiproton Decelerator (AD) in Geneva, is the first time that the electric charge of an anti-atom has been measured to high precision. Measuring the electric charge of antihydrogen atoms is a way to study any subtle differences between matter and which could account for the lack of antimatter in the universe.

In a paper published in the journal Nature Communications today, the ALPHA experiment reports a measurement of the electric charge of antihydrogen atoms, finding it to be compatible with zero to eight decimal places. This is the first time that the charge of an anti-atom has been measured to high precision and confirms our expectation that the charges of its constituents, the positron and antiproton, are equal and opposite.

"This is the very first study which has made a precise determination of a property of antihydrogen," said Professor Mike Charlton, who leads the UK effort in ALPHA from Swansea University. "This advance was only possible using ALPHA's trapping technique, and we are optimistic that further developments of our programme will yield many such insights in the future. We look forward to the restart of the Antiproton Decelerator program in August, so that we can continue to study antihydrogen with ever increasing accuracy."

Professor John Womersley, particle physicist and Chief Executive of the UK's Science and Technology Facilities Council (STFC) said that, "Though the result is not surprising it is a fundamental test that have equal and opposite electric charges. It is reassuring that nature behaves as expected, but as scientists we should never take anything for granted and measurements like this are therefore very important indeed."

Antiparticles should be identical to matter particles except for the sign of their electric charge. So while the hydrogen atom is made up of a proton with charge +1 and an electron with charge -1, the antihydrogen atom consists of a charge -1 antiproton and a charge +1 positron. We know, however, that matter and antimatter are not exact opposites - nature seems to have a one-part in 10 billion preference for matter over antimatter. However, we don't know why, so it is important to measure the properties of antimatter to great precision: the principal goal of CERN's AD experiments.

ALPHA achieves this by using a complex system of particle traps that allow antihydrogen atoms to be produced and stored for long enough periods to make detailed studies. Understanding the matter-antimatter asymmetry is one of the greatest challenges in physics today. Any detectable difference between matter and antimatter could help solve the mystery and open a window to new physics.

To measure the charge of antihydrogen, the ALPHA experiment studied the trajectories of antihydrogen atoms released from the trap in the presence of an electric field. If the had an electric charge, the field would deflect them, whereas neutral atoms would be undeflected. The result, based on 386 recorded events, gives a value of the antihydrogen as (-1.3±1.1±0.4) × 10-8, the plus or minus numbers representing statistical and systematic uncertainties on the measurement.

With the restart of CERN's accelerator chain getting underway, the laboratory's antimatter research programme is set to resume soon. Experiments including ALPHA-2, an upgraded version of the ALPHA experiment, will be taking data along with the ATRAP and ASACUSA experiments and newcomer AEGIS, which will be studying the influence of gravity on .

Explore further: CERN experiment produces first beam of antihydrogen atoms for hyperfine study

More information: Paper: An experimental limit on the charge of antihydrogen, www.nature.com/ncomms/2014/140… full/ncomms4955.html

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verkle
1 / 5 (16) Jun 03, 2014
Where did all the antimatter go?


Maybe there was not to begin with with. Scientists should re-think their assumed original conditions. Maybe there was no big bang after all. Quite likely. I think, very likely.
Maggnus
4.5 / 5 (17) Jun 03, 2014
Where did all the antimatter go?


Maybe there was not to begin with with. Scientists should re-think their assumed original conditions. Maybe there was no big bang after all. Quite likely. I think, very likely.
Of course you would think this, you believe God did it. How about you go stick your head back in the sand?
Caliban
4.1 / 5 (12) Jun 03, 2014
...nature seems to have a one-part in 10 billion preference for matter over antimatter."


This implies that the total mass(matter+antimatter) of the primordial universe was 10 billion times the observed mass today.

Which would go a long way towards explaining the apparent shortage of matter in the observable universe.

Whydening Gyre
2.3 / 5 (4) Jun 03, 2014
Opposite particles would have opposite spin , right? It's a chirality effect that produced more matter. A flip of the coin, if you will, that put a larger number of counter-clockwise spin particles in one place than of clockwise spin. It had a cumulative effect that "over powered" the other side, and just never stopped growing.
Just my humble opinion....
Nanowill
1 / 5 (10) Jun 03, 2014
There is a relatively simple theory that shows how electrons and protons were created in exactly equal numbers, i.e. there were no antiparticles created. This theory gives opposite electric charges and produces the particles masses to within empirical uncertainty. It also resolves the Large Number Problem, (LN = 5.708 x10^44) and other related issues in physics. So why is no body interested in this? Why does physics continue to trot out the same old dogma? Unfortunately physics is moving further and further from reality. Time for some major revisions. The truth will win out eventually, but I'd prefer sooner rather than later.
NanoWill
Nanowill
1 / 5 (10) Jun 03, 2014
I believe he Big Bang Theory is completely wrong and the notion arose form religious concepts. If electrons and protons are formed simultaneously it is easily shown the Universe started small and is continuously growing. The net electric charge is zero, the net angular momentum is zero, the net equivalent mass is zero. And the Universe mass density is decreasing with the calculated present value exactly that observed. The electron - proton mass ratio is calculable as is the MOND constant, and yes, gravity is quantized. Its all on the web, and has been for some years.
NanoWill
typicalguy
3.8 / 5 (9) Jun 03, 2014
I wish phys.org would close down comments on articles like Popular Science did. If phys.org wants a place for discussion they can have a message board where people can migrate. I hate that people that aren't familiar with this site might think that these people know what they're talking about. Many comments here are nothing more than ideas made up by laypeople that have no math, formula, or experiment to back up claims. When asked for any kind of evidence, you're told that their thought experiment is "good enough" for science.

The best information still points to a big bang, that isn't to say that it's 100% certain but it's likely. Electron's and protons "created in equal numbers" is not proven and in fact makes very little sense as most atoms have more than one electron. If they were balanced then we'd have a universe of ionized gas clouds. Additionally, when matter is created in labs, the anti-particle is always created. This is basic stuff.
Seeker2
1 / 5 (3) Jun 04, 2014
I'd say there is plenty of antimatter but it's gravitationally repulsive as matter is attractive. And gravitationally neutral with matter. So it's out there in intergalactic space as individual particles. Their minimum energy configuration would be evenly spaced, similar to matter's minimum energy configuration is closely packed - leading eventually to big bang events. So space is flat because antimatter repulsive forces exactly balance the attractive forces of matter.
cantdrive85
1.4 / 5 (10) Jun 04, 2014
Many comments here are nothing more than ideas made up by laypeople that have no math, formula, or experiment

Well I wonder what a Nobel laureate has to say about the matter...

"I was there when Abbe Georges Lemaitre first proposed this theory [Big Bang]. Lemaitre was, at the time, both a member of the Catholic hierarchy and an accomplished scientist. He said in private that this theory was a way to reconcile science with St. Thomas Aquinas' theological dictum of creatio ex nihilo or creation out of nothing." Hannes Alfven

If they were balanced then we'd have a universe of ionized gas clouds.


What do the folks at NASA have to say about this...

"99.9 percent of the Universe is made up of plasma," says Dr. Dennis Gallagher, a plasma physicist at NASA's Marshall Space Flight Center.

This is basic stuff.

I wish phys.org would close down comments


"The free, unhampered exchange of ideas and scientific conclusions is necessary for the sound development of science, as it is in all spheres of cultural life. " Einstien
George_Rajna
1 / 5 (1) Jun 04, 2014
The secret of matter - antimatter asymmetry is in the Planck Distribution Law: https://www.acade...g_Theory
TimLong2001
1 / 5 (3) Jun 04, 2014
The binary photon structure of (+) amd (-) charges, resulting in positron-electron pair formation for 1.0216 Mev gammarays,, indicates that the photon is composed of equal amounts of matter and antimatter. As a fundamental constituent of all matter, this would imply that the photon contains the "missing" antimatter. And the internal interaction provides its propulsion mechanism. A "finding" of the Los Alamos (LANL) fusion project, terminated in the late 1980's, was that opposite charges acted at 90 degrees. This provides the spin necessary to establish a rotating system with charge attraction and centrifugal force balancing to establish a specific orbital radius (providing a specific wavelength and frequency) of E-M radiation.
rockwolf1000
3.8 / 5 (9) Jun 04, 2014
I wish phys.org would close down comments on articles like Popular Science did. If phys.org wants a place for discussion they can have a message board where people can migrate. I hate that people that aren't familiar with this site might think that these people know what they're talking about. Many comments here are nothing more than ideas made up by laypeople that have no math, formula, or experiment to back up claims. When asked for any kind of evidence, you're told that their thought experiment is "good enough" for science.


I wish people who don't like the comments section would just move on. This is a science site for the GP. laymen if you will. I hate that assholes like you think they know best and suggest this site close down the very section where learning takes place. Popular Science is for dumb-asses. I suggest you return there. You want formulas, graphs and math? Subscribe to Nature.

If you don't like the comments - don't fucking read them. Retard!
rockwolf1000
4.1 / 5 (10) Jun 04, 2014
[q
The best information still points to a big bang, that isn't to say that it's 100% certain but it's likely. Electron's and protons "created in equal numbers" is not proven and in fact makes very little sense as most atoms have more than one electron. If they were balanced then we'd have a universe of ionized gas clouds. Additionally, when matter is created in labs, the anti-particle is always created. This is basic stuff.

You bitch about the comments section. Then add your own unqualified opinion.

Can you say hypocrisy?
Incosa
1 / 5 (2) Jun 04, 2014
The antimatter disappeared nowhere - it's finely divided in form of dark matter all around us. In such level of division the negative gravitational charge of antimatter applies, which does prohibit the antimatter in agglomeration typical for normal matter.

You may think, that the antimatter is formed with bubbles with less or more thick walls. The interior of bubbles is gravitationally repulsive with respect to each other, the positive curvature of space-time inside of wall of bubbles balances this repulsive force less or more extensively. At the case of heavier antiparticles particles with thicker walls (positrons, antiprotons) the mass and positive gravitational attraction of bubble walls outperforms the repulsive behavior of bubble interior and such a antiparticles would coalesce under their gravity quite normally.
I wish phys.org would close down comments on articles like Popular Science did
You can disable the comment section with single click: it will remain invisible for you and the result will be equivalent.
ebaduanajr
1 / 5 (7) Jun 05, 2014
The Big Bang never happened. Antimatter or rather antiparticles are created from the collisions. This has to do with the charge or direction of spin of a particle: positive charge spins counterclockwise and negative charge spins clockwise. By nature proton spins counterclockwise and electron spins clockwise. Through collisions, a proton could spin in the opposite direction, hence we have antiproton.

One of the supporting proof for the Big Bang is said to be the presence of cosmic microwave background radiation (CMBR), which was said to have been predicted by George Gamow. This is not true. Stars around us produces photons of light in the ranges of the spectrum of light. In fact, we take images of galaxies and nebulas in the x-ray and infrared range to see what is really happening to them. Thus, microwave is emitted also by the stars and is not a remnant of the Big Bang.
matt_roadhouse
1 / 5 (2) Jun 06, 2014
Where did all the antimatter go?


Maybe there was not to begin with with. Scientists should re-think their assumed original conditions. Maybe there was no big bang after all. Quite likely. I think, very likely.
Of course you would think this, you believe God did it. How about you go stick your head back in the sand?


Why is it so easy to believe that after 1 billion years life 'happened' on Earth, but so hard to grasp the concept of after 15 billion years the universe is sentient ?
Accounts
5 / 5 (2) Jun 06, 2014
Just mind wandering here but I wonder if the matter/anti-matter asymmetry could somehow be related to the observed forward/reverse time asymmetry?

- Greg
Caliban
5 / 5 (2) Jun 06, 2014
Just mind wandering here but I wonder if the matter/anti-matter asymmetry could somehow be related to the observed forward/reverse time asymmetry?

- Greg


@ greg,

Gave you a fiver, just for posing a thoughtful question.
Jeffhans1
not rated yet Jun 09, 2014
I always assumed it was because of the way hydrogen forms magnetic bonds and clumps together in a vacuum. This allows the density to increase until a large enough cloud starts to collapse due to the magnetic and gravitational effects. Anti-hydrogen on the other hand, doesn't form the magnetic bonds as easily and therefor doesn't stay in dense enough clouds to allow for star formation as easily. Anti-hydrogen never has many stars or galaxies formed beyond the ones after the big bang. Anti-hydrogen would still be attracted by gravity, but its own repulsive nature keeps it from becoming dense enough to form plasma.