Negative Matter Blackholes?

[ZacharyNardolillo]

This is something that just recently occured to me. So Antimatter has Anti-gravity: It floats away from positive matter, but floats towards other negative matter. So this made me think: There could be pretty much anything out there that we see now, only it would be made of negative matter. So it made me think again, perhaps there are negative blackholes out there, sucking up any antimatter that gets too close, and repels positive matter with immense force. Do you guys think this is also plausible or know if they have ever found any such things?

[granpa]

the usual argument against that is the photon

the photon is its own antiparticle so would it be attracted or repelled by antimatter?

[modest]

This is something that just recently occured to me. So Antimatter has Anti-gravity: It floats away from positive matter, but floats towards other negative matter.

 

While it has never been tested (yet), the consensus is that antimatter and matter are attracted gravitationally.

 

~modest

[Qfwfq]

While it has never been tested (yet)

The Eddington test settles the question.

[modest]

The Eddington test settles the question.

 

How so? The sun is made of matter.

 

The gravitational interaction of antimatter with matter or antimatter has not been conclusively observed by physicists. While the overwhelming consensus among physicists is that antimatter will attract both matter and antimatter at the same rate that matter attracts matter (and antimatter), there is a strong desire to confirm this experimentally, given that consensus in science is but hypothesis open to falsification.

 

Wikipedia -- Gravitational interaction of antimatter

 

~modest

[HydrogenBond]

antimatter is the extension of the concept of the antiparticle to matter, where antimatter is composed of antiparticles in the same way that normal matter is composed of particles. For example, a positron (the antiparticle of the electron) and an antiproton can form an antihydrogen atom in the same way that an electron and a proton form a normal matter hydrogen atom.

 

Anti-matter uses the same mass as matter but only switches the charge. One would not expect gravity to notice since the mass is the same. Although an electron and its anti the positron will annihilate each other the positron is not very aggressive to the proton since nuclei can exchange positrons.

 

The term antimatter was first used by Arthur Schuster in two rather whimsical letters to Nature in 1898,[2] in which he coined the term. He hypothesized antiatoms, whole antimatter solar systems and discussed the possibility of matter and antimatter annihilating each other. Schuster's ideas were not a serious theoretical proposal, merely speculation, and like the previous ideas, differed from the modern concept of antimatter in that it possessed negative gravity.

 

Anti-matter is more about swapping charge with nature appearing to favor plus on the proton and negative on the electron. If it forms, nature tends to make sure it doesn't last very long.

[Qfwfq]

How so? The sun is made of matter.

But the effect involves a photon. Even your Granpa knows that a photon is its own antiparticle so, if its deflection isn't zero it's gotta be the same for an electron as for a positron. Much of the energy content of hadrons is due to the interaction bosons. The conjecture would be in conflict with the equivalence principle anyway.

[maddog]

I think I have to side with Qfwfq on this one. To consider where antimatter has a gravitational symmetry in my mind would

another universe, not this one (a very strange one indeed).

 

Think of annihilation pairs (electron & positron). These are attractive due the change in charge. We get a positive

energy from the annihilation (positive energy). E = mc^2. This implies the mass of the positron is positive.

 

As Qfwfq repeated that photon being their own antiparticle, I would conclude have no interaction with each other.

 

As I think about this, I see gravity as antimatter/matter symmetry unprejudiced. Gravity care not what your chiral potential is (normal/anti-).

 

In an electric field an electron is deflected one way and the positron is the opposite. In a gravity field, I would predict the

deflection (slight as it is) to be in the Same direction.

 

maddog

[modest]

But the effect involves a photon. Even your Granpa knows that a photon is its own antiparticle so, if its deflection isn't zero it's gotta be the same for an electron as for a positron.

 

I wouldn't say exactly that.

 

A photon is neither matter nor antimatter (nor both). If a photon is gravitationally attracted by matter it doesn't necessarily prove that antimatter will be attracted (at least, not by the same amount), nor would it prove that an antiparticle would be attracted.

 

Much of the energy content of hadrons is due to the interaction bosons.

 

Yes

 

I make the same point here, and I've seen Craig make the point before. At best, I think this would prove that atoms of matter and antimatter are attracted by roughly the same force. It would not, however, insist that an antiparticle like a positron is attracted.

 

The conjecture would be in conflict with the equivalence principle anyway.

 

The wiki article I linked talks about that. There have been, however, papers which propose repulsive antimatter in the framework of GR:

 

http://www.citebase.org/fulltext?format=application%2Fpdf&identifier=oai%3AarXiv.org%3Agr-qc%2F9906012

 

I think it will be good to directly test the proposition. From previous discussion in the "Dominium model by Hasanuddin" thread, it appears this may happen soon.

 

~modest

[Qfwfq]

A photon is neither matter nor antimatter (nor both).

This doesn't matter, if you excuse the pun. Unless we find a whole different GR it isn't the matter that matters, it's the energy-momentum tensor.

 

What's the difference anyway, between matter and antimatter? Why should bosons interact differently with one than with the other? Are you sure it could be sorted out by revising only GR without also messing up QED and QCD?

[modest]

Fair enough, but my comment wasn't concerning what GR or QED predicts. I was simply saying that the hypothesis, matter is gravitationally attracted by anitmatter, has not been tested. Wiki makes the same point,

 

The gravitational interaction of antimatter with matter or antimatter has not been conclusively observed by physicists. While the overwhelming consensus among physicists is that antimatter will attract both matter and antimatter at the same rate that matter attracts matter (and antimatter), there is a strong desire to confirm this experimentally, given that consensus in science is but hypothesis open to falsification.

 

Wikipedia -- Gravitational interaction of antimatter

 

and there is an experiment designed and efforts underway to test the hypothesis (at CERN, if I recall correctly). I'd be extraordinarily surprised if the result were anything other than what is expected, I was just saying "it has never been tested (yet)".

 

~modest