## Anti-hydrogen Captured, Held For First Time

by Nancy Atkinson[/caption]

Can warp drive be far behind? A paper published in this week’s edition of Nature reports that for the first time, antimatter atoms have been captured and held long enough to be studied by scientific instruments. Not only is this a science fiction dream come true, but in a very real way this could help us figure out what happened to all the antimatter that has vanished since the Big Bang, one of the biggest mysteries of the Universe. “We’re very excited about the fact that we can actually now trap antimatter atoms long enough to study their properties and see if they’re very different from matter,” said Makoto Fujiwara, a team member from ALPHA, an international collaboration at CERN.

Antimatter is produced in equal quantities with matter when energy is converted into mass. This happens in particle colliders like CERN and is believed to have happened during the Big Bang at the beginning of the universe.

“A good way to think of antimatter is a mirror image of normal matter,” said team spokesman Jeffrey Hangst, a physicist at Aarhus University in Denmark. “For some reason the universe is made of matter, we don’t know why that is, because you could in principle make a universe of antimatter.”

In order to study antimatter, scientists have to make it in a laboratory. The ALPHA collaboration at CERN has been able to make antihydrogen – the simplest antimatter atom – since 2002, producing it by mixing anti- protons and positrons to make a neutral anti-atom. “What is new is that we have managed to hold onto those atoms,” said Hangst, by keeping atoms of antihydrogen away from the walls of their container to prevent them from getting annihilated for nearly a tenth of a second.

The antihydrogen was held in an ion trap, with electromagnetic fields to trap them in a vacuum, and cooled to 9 Kelvin (-443.47 degrees Fahrenheit, -264.15 degrees Celsius). To actually see if they made any antihydrogen, they release a small amount and see if there is any annihilation between matter and antimatter.

The next step for the ALPHA collaboration is to conduct experiments on the trapped antimatter atoms, and the team is working on a way to find out what color light the antihydrogen shines when it is hit with microwaves, and seeing how that compares to the colors of hydrogen atoms.

The online edition of Nature, that is.

Print publication will be in one of the next editions.

*stickler for detail*

far from warp drive…but getting there 🙂

The fundamental discrete symmetry of nature is the CPT group. Suppose you have a wave function Y_q(x,t), where q is charge, x is space and t is time. The CPT are letter swhich stand for the operation

C*Y_q(x,t) = Y_{-q}(x,t) charge reversal

P*Y_q(x,t) = Y_q(-x,t) space reversal

T*Y_q(x,t) = Y_q(x,-t) time reversal

The CPT operation (composition) CPT*Y_q(x,t) = Y_{-q}(-x,-t) and the symmetry is that this is Y_q(x,t). Therefore the composition CPT = 1. This symmetry turns out to be very important for local quantum field theories with Lorentz symmetry — or that transform by relativity.

It turns out that CP can be violated, which corresponds to a T violation as well. Yet CPT = 1 remains. The violation of CP symmetry means the wave function CP*Y_q(x,t) = Y_{-q}(-x,t) can differ from Y_q(x,t) in strange ways.

This unfortunately has nothing to do with war drives, which I suppose comes from the Star Trek reference to anti-matter pods.

LC

Matter and antimatter annihilation releases about 100 times more energy than nuclear fusion.

Aneutronic fusion doesn’t emit neutrons and release millions of times more energy than chemical reactions.

Production of enough quantities of antimatter is impossible in a short time, but aneutronic fusion can be a reality soon and could power space drives.

I agree with LBC’s final sentence. Every time something like this is discovered virtually every news outlet will show a picture of the Enterprise, make some pathetic reference to Mr.Scott or warp-drive and say that the exploration of the distant stars is only a few years away.

I’m all for engaging the public by using analogies most can understand but these type of reports are as good as useless. Look at the report that the LHC was going to destroy us all with a black hole, how the Higgs boson is refered to as The God Particle, how every NEO is classified as ‘an Earth-killer’.

Very annoying.

Paul Eaton-Jones: This is indeed rather normative mainstream research. Tests of CPT symmetry show it is correct up to 10^{-33}GeV. So don’t expect any upset in physics with this work with antihydrogen.

This will not be some new energy source. The antimatter or antihydrogen has a mass that is given by the energy you input into the system with the accelerator. So this is not an energy source. As for aneutronic fusion, that looks like science fiction more than science.

LC

This momentous feat could be as important as the confirmation of the theory of relativity and open anew branch in Physics

Here`s a scenario. Highly unscientific but possibly interesting anyway. Interested in how this could be explained away (without the math).

Okay, he talks about symmetry. The big bang or inflation theory seems awfully one sided to me and therefore unsymmetrical. What if it occurred as suggested but included another universe in the other direction made of antimatter? Yes, I realize the inflationary cone does not illustrate actual direction but in that other universe would be all the antimatter and anyone there would be wondering where all the anti-antimatter was. It just stands to reason that the two would not be created in the same universe as then that universe would self annihilate and really never have been at all. Then the net production of matter would be zero and not violate a whole bunch of laws of physics. Just saying is all! (:

The theory of anti-matter in physics came about by the following. In special relativity there is the momentum interval, which you can derive or look up, which says

(mc^2)^2 = E^2 – (pc)^2

for E = energy and p = momentum. if you set the momentum p = 0 you get the celebrated E = mc^2. This can be easily looked up. In quantum mechanics you replace the variables p and E with their quantum operators

p –> -ih&/&x, E = ih&/&t

for & meaning partial derivative and h = Dirac-Planck unit of action. If you plug this into the above equation and assume it acts on a quantum wave Y you get

&^2Y/&t^2 – &^2Y/&x^2 + (mc^2)^2Y/h.

This is the Klein-Gordon equation for a relativistic wave that has zero spin.

To include spin what Dirac realized is that some spin matrices have properties s^2 = -1 and he constructed more general spin operators so one could take the “square root” of the K-G equation above. Now the square root of something has two roots, and one root is matter, the other anti-matter.

The spacetime cosmology we observe might have an arrow of time that is fixed by certain phase conditions within a larger higher dimensional spacetime. With the mulitiverse concept, or a universe with multiple spacetime cosmologies, others might have opposite time directions or be dominated by what we might call anti-matter.

LC

PS, the above second order differential should be set to zero

&^2Y/&t^2 – &^2Y/&x^2 + (mc^2)^2Y/h = 0.

Oh, and if you don’t know about differential equations — pity.

LC

LBC I have a question for you.

Once I calculated how big the event horizon would be for a LHC proton collision turning into a black hole and came up with a number that is way smaller than the Planck scale, the same for the evaporation time.

I thought something smaller than a Planck scale means = it makes no sense anymore.

How do I have to interpret this:

A: The event horizon will be minimal the Planck length?

B: No black hole can be formed since it has not enough mass

C: Something I have not thought about.

The black hole at TeV in energy is a BPS type of black hole. There is a renormalization flow from unification energy at 1TeV to the Planck energy. At lower energy the black hole is determined more by gauge charges than mass, and the curvature is within the compactifiied dimensions of string theory, or Dp-branes, This gets into Randall’s warped dimensions stuff, but at these lower energy world black hole warps more outside of spacetime. As you go to higher energy the continuous RG flow converts this quantum BPS black hole into a full quantum gravity black hole at the Planck scale.

I wrote an essay on this that is semi-mathematical a few weeks ago. I could apply that here, though I am not sure whether that many would read it or understand it. I might wait until there is a topic more relevant to that subject.

LC

LBC I am patiently waiting until we have another black hole or LHC story 🙂

I gather it is answer C: 😉

But the event horizon would be basically a plank scale, because of stuff.

It is basically C. What is worth pondering is the next generation of particle physics machines after the LHC. We might get the very low energy BPS black holes ~ AdS ~ QCD physics with the LHC. To further complete the RG flow to high energy we should try somehow to get a look at energy up to 1000 TeV or even a million TeV. My thinking is we will have to do some creative stuff with cosmic rays. Of course control on statistics gets shaky.

The one idea is to arrange for an array of balloons in the upper atmosphere which have various detectors. The Earth’s upper atmosphere is then a sort of particle calorimeter, similar to ALICE or ATLAS at the LHC. Another idea is to put in orbit two spacecrafts. One points a high powered laser at a cosmic ray source. Another spacecraft is a detector system. The cosmic rays scatter with the laser photons and the scatter products are measured by the detector system. That part is a bit tough to arrange. It is not entirely trivial to get an ATLAS sized hadron calorimeter type of device in space. Further, since the scattering is not going to be in the center of mass frame, the detector has to be an array which measures scattering particles coming at it, and not scattering in all directions. It is possible that the high energy laser is placed in Earth orbit and the ground based balloon system then serves as the detector.

The point of schemes like this will be to get signatures of scattering events which have signatures of this conformal quantum field RG flow. This will not focus so much on detecting new particles, such as a search for the Higgs at 115GeV or the tan(beta) parameter for the MSSM Higgs etc. So the stats might be liberalized some.

LC

I do not understand how magnetic fields of matter

1) Can control antimatter and contain it.They should have no affect on matter.

2) Why do the magnetic fields of energy(mass) not annihilate the antimatter?

Chris Landau

For a particle of with the state vector Y(q, s, …,x, t) there are these quantum numbers q = charge s = isopsin and then may be others. For a particle to annihilate this state it has to have the opposite quantum numbers so if q = 1 the antiparticle has q = -1 and so forth. An anti electron and proton can be pushed together and they wil never annihilate. A proton has a baryon number = 1 and the anti electron has a lepton number = -1. Yet those two quantum numbers don’t cancel each other out.

Anti-matter has the same mass-energy content as matter. An electron and anti-electron annihilate each other to give photons with energy E = 2mc^2, for m the mass of the electron and anti-electron.

LC

I understand that an electron and positron will annihilate and that a positron and anti-proton would combine to form an anti-neutron with some energy release.What concerns me is are the magnetic fields made of antimatter or are the magnetic fields made of electromagnetic matter? if our magnetic fields can affect antimatter, in our universe, then antimatter magnetic fields must be affecting the objects in our universe? Is that happening? As you have stated an anti-electron and proton have no affect on each other.Do we “see” anti-matter electromagnetic fields in our universe and if so how do they affect our pulsars and black holes? Does increasing density convert matter to antimatter in black holes or pulsars to eliminate mass? Does this solve the mass-density perpetual increase of black holes?

Thanks

Chris

A proton has baryon number = +1, lepton number = 0 and charge = +1. A electron has baryon number = 0, lepton number = 1 and charge = -1. Put the two together and you get baryon number = +1 lepton number = +1 and charge = 0. So there is an excess lepton number, and this is carried off by a neutrino. For the positron plus anti-proton the logic is the same with the signs on these unital quantum numbers reversed.

The electromagnetic field or photon only carries the quantum number for spin = 1. It carries no charges or quantum numbers assigned to fermions, such as protons, electrons, neutrinos and so forth. So there is no anti-photon. The matter-antimatter structure comes from the Dirac equation with two roots. This pertains to spin = 1/2 particles or fermions, or the quantum numbers they carry. Things get a bit complicated with nonabelian gauge vector bosons which also carry these numbers.

LC