Has anyone read or heard about this article or knows or has an opinion about it or the author?

Thanks

http://phys.org/news/2011-04-antimatter-gravity-universe-expansion.html

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merle - vote yes for freedom of speech

Merle thanx for the good read.

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Has anyone read or heard about this article or knows or has an opinion about it or the author?

Thanks

http://phys.org/news/2011-04-antimatter-gravity-universe-expansion.html

Supersymmetry predicts a partner particle for each particle in the Standard Model of physiscs.
There are also 4 force carriers so why not 4 anti force carriers?
http://home.web.cern.ch/about/physics/supersymmetry

Merle thanx for the good read.

+1, welcome back :)

most physicists think that the gravitational behavior of antimatter should always be attractive, as it is for matter. However, the question of whether the gravitational interaction between matter and antimatter is attractive or repulsive so far has no clear answer.

There is the overwhelming consensus among physicists that antimatter will attract both matter and antimatter at the same rate that matter attracts matter. They are dying to confirm this hypothesis.

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Matter and anti-matter will annihilate with nearly 100% efficiency in energy production. It is the ideal propulsion fantasy as seen in Star Trek. The problem is where do we get it or make it cheaply and in abundance and how do we store it.

At CERN, the AEgIS experiment will test the gravitational bending of antihydrogen atoms. CERN is the main source of antimatter and has developed a series of traps, the Penning traps, to contain antimatter.
Tullio

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Matter and anti-matter will annihilate with nearly 100% efficiency in energy production. It is the ideal propulsion fantasy as seen in Star Trek. The problem is where do we get it or make it cheaply and in abundance and how do we store it.

Nobody has been capable of storing antihydrogen atoms so far, but this is the goal of our research collaboration in the ALPHA Project.
http://socrates.berkeley.edu/~fajans/ALPHA_Spanish/EN_produccion%20new.htm
The production and storage of antimatter is a costly process, both in terms of time and money. The production of a nanogram (a billionth of a gram) of antihydrogen costs a few hundred million euros.

Correction:)

In November 2010, the ALPHA collaboration announced that they had trapped 38 antihydrogen atoms for a sixth of a second,[21] the first confinement of neutral antimatter. In June 2011, trapped 309 antihydrogen atoms, up to 3 simultaneously, for up to 1,000 seconds.[22][23] They then studied its hyperfine structure, gravity effects, and charge. ALPHA will continue measurements along with experiments AEGIS and GBAR.

Read the September issue of CERN Courier. There is an article on antiprotons and antihydrogen.
Tullio

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Thanks Tullio.
I didn't know this:

Antihydrogen has a magnetic dipole moment (that of the positron), which means that it can be captured in an inhomogeneous magnetic field.

Scientists hope studying antihydrogen may shed light on the baryon asymmetry problem or why there is more matter than antimatter in the universe.

most physicists think that the gravitational behavior of antimatter should always be attractive, as it is for matter. However, the question of whether the gravitational interaction between matter and antimatter is attractive or repulsive so far has no clear answer.

Great! Thanks everybody. I love the quote above the best. It answers the main question I had relating to this article. It's nice to know some people aren't sure of what they don't know yet.

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merle - vote yes for freedom of speech

At CERN, the AEgIS experiment will test the gravitational bending of antihydrogen atoms. CERN is the main source of antimatter and has developed a series of traps, the Penning traps, to contain antimatter.
Tullio

Thanks Tullio
I would read that issue of CERN from sept, but I doubt I could understand it. Above you are saying that this experiment might confirm whether antimatter would attract or repulse matter gravitationally. Correct? When are they testing it and how long do you think it would take for some kind of answer?

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merle - vote yes for freedom of speech

I don't know the timescale, but I shall follow the experiment and publish the result. It may be a stet forward.
Tullio

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At CERN, the AEgIS experiment will test the gravitational bending of antihydrogen atoms. CERN is the main source of antimatter and has developed a series of traps, the Penning traps, to contain antimatter.
Tullio

Thanks Tullio
I would read that issue of CERN from sept, but I doubt I could understand it. Above you are saying that this experiment might confirm whether antimatter would attract or repulse matter gravitationally. Correct? When are they testing it and how long do you think it would take for some kind of answer?

The principle of universality of free fall (or Weak Equivalence Principle, WEP) states that all bodies fall with the same acceleration, independent of mass and composition. The WEP has been tested with very high precision for matter but never (directly) for antimatter.
Here is what the AEGIS experiment does.
http://aegis.web.cern.ch/aegis/home.html
The principal goal of the AEGIS experiment is to test the Weak Equivalence Principle with antihydrogen atoms at the European laboratory for particle physics (CERN), using the antiproton decelerator (AD) to provide antiprotons and a 22Na source to provide antielectrons, which we combine to form antihydrogen atoms. Tests with charged antiparticles are hopeless, given the extreme weakness of gravity in comparison with the other forces, while tests with (neutral) antihydrogen atoms are merely extremely difficult.

Has anyone read or heard about this article or knows or has an opinion about it or the author?

Thanks

http://phys.org/news/2011-04-antimatter-gravity-universe-expansion.html

Along with critique(2) for original paper(1) and the answer on that critique(3) all those 3 articles form quite interesting reading, thanks.

And some citation from last one:

Similarly, visible photons, i.e. retarded ones, are
repelled by an antimatter gravitational field, thus
providing a test for the theory: even if antimatter
can not be detected directly by its advanced pho-
tons, it could be revealed by its gravitational effect
on the retarded radiation coming from the back-
ground, giving rise to an antigravitational lens-
ing, i.e. a diverging lens type effect, which brings
the images of the background sources closer to the
lensing object.

This provides experimental way to check this theory by astronomical observations instead of CERN-like particle measurements. Gravitation-related effects much more readily detected on astronomical scale than on micro-particle one.
I did not hear about such type of gravitational lensing, AFAIK all found so far lenses (and they found in number) are from "plus-type" gravity. Would be interesting to find "minus-gravity" one...

(1)http://iopscience.iop.org/article/10.1209/0295-5075/94/20001/meta;jsessionid=5257AC04603F89453F7C84F95C21B8BE.c1
(2)http://link.springer.com/article/10.1007%2Fs10509-011-0939-8
(3)http://arxiv.org/abs/1109.1201

Merle thanx for the good read.

+1, welcome back :)

most physicists think that the gravitational behavior of antimatter should always be attractive, as it is for matter. However, the question of whether the gravitational interaction between matter and antimatter is attractive or repulsive so far has no clear answer.

There is the overwhelming consensus among physicists that antimatter will attract both matter and antimatter at the same rate that matter attracts matter. They are dying to confirm this hypothesis.

Thanks for the welcome back Julie. It was bothering me that I didn't say that before.

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merle - vote yes for freedom of speech

Merle thanx for the good read.

+1, welcome back :)

most physicists think that the gravitational behavior of antimatter should always be attractive, as it is for matter. However, the question of whether the gravitational interaction between matter and antimatter is attractive or repulsive so far has no clear answer.

There is the overwhelming consensus among physicists that antimatter will attract both matter and antimatter at the same rate that matter attracts matter. They are dying to confirm this hypothesis.

Thanks for the welcome back Julie. It was bothering me that I didn't say that before.

No problem my friend.

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rOZZ
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Pictures