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Antimatter sun

by cosmicpencil
Tags: antimatter
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cosmicpencil
#1
Dec19-09, 06:18 PM
P: 23
what is the difference between antimatter sun and a matter one, thanks.
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mgb_phys
#2
Dec19-09, 06:33 PM
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From a distance, nothing
As far as we know (almost) all nuclear reactions, physical laws and chemistry is identical for matter and anti-matter.
Unless matter came into contact with the sun you wouldn't know
cosmicpencil
#3
Dec19-09, 06:42 PM
P: 23
Dosent the gama ray ration differs?

Could this kind of sun permit life?, thanks.

Bob S
#4
Dec19-09, 07:04 PM
P: 4,663
Antimatter sun

I think the neutrino/anti-neutrino ratio would be different if the Sun were made of antimatter. The "missing solar neutrinos" problem was the focus of neutrino research for a while. Also, the solar wind (slow proton plasmas) would be antimatter, which would have been detected by now.
Bob S
mgb_phys
#5
Dec19-09, 07:05 PM
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Depends wether the question is, would we know if our sun was anti-matter - then yes very definitely.
If they meant could an anti-earth go around an anti-sun in a distant anti-galaxy, then yes.
tataraperz
#6
Dec19-09, 09:26 PM
P: 5
Could there be "humans" made of antimatter and be excactly equal to us in every aspect?
qraal
#7
Dec20-09, 12:46 AM
P: 775
Quote Quote by tataraperz View Post
Could there be "humans" made of antimatter and be excactly equal to us in every aspect?
Yes, there could. However there probably isn't enough antimatter in this Universe concentrated sufficiently to make an antimatter star with planets - matter out numbers antimatter about 1 billion or so to 1. Thus antimatter is spread out too thinly to meet up with other antimatter.

However cosmic rays do make some when they collide with regular matter - their relativistic energy gets turned into equal amounts of matter and antimatter. A magnetic field can split the two kinds of matter up and some antimatter can collect in the magnetospheres of the big planets. Perhaps a few micrograms or so. We could gather enough antihydrogen to make a snow-flake perhaps.
supergalactic
#8
Jan17-11, 02:46 AM
P: 3
Quote Quote by Bob S View Post
I think the neutrino/anti-neutrino ratio would be different if the Sun were made of antimatter. The "missing solar neutrinos" problem was the focus of neutrino research for a while. Also, the solar wind (slow proton plasmas) would be antimatter, which would have been detected by now.
Bob S
I think this is a really interesting topic, I read at the link below that there is in fact antimatter on the sun and in its flares (was published in 2003).

http://www.nasa.gov/vision/universe/...ntimatter.html

Kind of related, I wanted to ask, are both the sun and earth in the Orion arm for certain?
twofish-quant
#9
Jan17-11, 02:59 AM
P: 6,863
Quote Quote by Bob S View Post
I think the neutrino/anti-neutrino ratio would be different if the Sun were made of antimatter. The "missing solar neutrinos" problem was the focus of neutrino research for a while. Also, the solar wind (slow proton plasmas) would be antimatter, which would have been detected by now.
The signature of anti-matter is 511 kev Gamma rays.

Which have been detected in lighting

http://news.nationalgeographic.com/n...science-space/
supergalactic
#10
Jan17-11, 10:33 AM
P: 3
Quote Quote by twofish-quant View Post
The signature of anti-matter is 511 kev Gamma rays.

Which have been detected in lighting

http://news.nationalgeographic.com/n...science-space/
Whoa 100 trillion positrons, this just happened and I guess it hit their spacecraft twice!?! Thought that might knock out all the electronics, wow, what a coincidence that it was over Egypt too!

Could it be that a lowt amount of positrons are always meeting with earths electrons, but when lightning happens, there is simply more antimatter present?

Either way, I think the baryon asymmetry theory might start changing. Thanks for sharing this, good find.
Radrook
#11
Jan26-11, 08:09 AM
P: 334
Imagine an antimatter rogue star plowing its way through a thick regular matter dust and/or predominantly hydrogen cloud. Harmless fireworks galore? Or the eventual disintegration of the star itself? Of course dust cloud density and duration of the passage have to be taken into consideration.
Janus
#12
Jan26-11, 10:42 AM
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Quote Quote by supergalactic View Post
Whoa 100 trillion positrons, this just happened and I guess it hit their spacecraft twice!?! Thought that might knock out all the electronics,
The total amount of energy released by the anihlation of that many positrons equals ~16 joules, or the amount of energy a 100w light bulb uses in 1/6 sec.
HallsofIvy
#13
Jan26-11, 02:59 PM
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Quote Quote by supergalactic View Post
Whoa 100 trillion positrons, this just happened and I guess it hit their spacecraft twice!?! Thought that might knock out all the electronics, wow, what a coincidence that it was over Egypt too!
What does being "over Egypt" have to do with any thing?

Could it be that a lowt amount of positrons are always meeting with earths electrons, but when lightning happens, there is simply more antimatter present?
No, lightning has nothing to do with "anti-matter".

Either way, I think the baryon asymmetry theory might start changing. Thanks for sharing this, good find.
lpetrich
#14
Jan26-11, 09:40 PM
P: 530
The macroscopic properties of an antimatter object are identical to those of its corresponding ordinary-matter object, with the exception of sign changes for electric charges and related quantities. Thus, an antimatter star would look exactly like an ordinary-matter one.

The weak interaction, however, violates charge symmetry (C), meaning that one can detect matter-antimatter asymmetry with it. It also violates parity symmetry (P), meaning that one can distinguish a reaction from its mirror image. But they conserve C and P together (CP), meaning that if one does not have some direction references, like the directions of distant stars and galaxies, one won't be able to tell ordinary matter from antimatter.

However, weak-interaction parity violation mostly affects of the directions of particles' spins, so it's VERY hard for it to have a measurable macroscopic effect.

All is not lost, however. Some decays of some mesons are known to violate CP, notably certain decays of neutral kaons. These can be used to distinguish ordinary matter and antimatter -- which way do the asymmetries go?
twofish-quant
#15
Jan28-11, 05:06 AM
P: 6,863
Quote Quote by Radrook View Post
Imagine an antimatter rogue star plowing its way through a thick regular matter dust and/or predominantly hydrogen cloud. Harmless fireworks galore? Or the eventual disintegration of the star itself? Of course dust cloud density and duration of the passage have to be taken into consideration.
I smell a test question for an intro astronomy class!!!!
lpetrich
#16
Jan28-11, 01:51 PM
P: 530
It should be easy to get rough estimates. The star will almost certainly be producing a stellar wind, and it will likely react with the interstellar medium before it reaches the star's photosphere. Where it reacts is another story; one will have to be careful about collision cross sections and mean free paths, however.

One also has to watch out for what happens when particles and antiparticles meet each other -- what they leave behind as they annihilate. Electrons and positrons will make gamma rays, and nucleons and antinucleons mostly pions. I say "nucleons", because protons and antineutrons can annihilate, as can antiprotons and neutrons. Pions are strongly interacting, and they will not travel very far in a nucleus. So an antiproton or an anti-alpha hitting a nucleus (or its matter-antimatter reversal) will cause the nucleus to fission or even disintegrate.
supergalactic
#17
Jan31-11, 05:00 PM
P: 3
Quote Quote by HallsofIvy View Post
What does being "over Egypt" have to do with any thing?
Egypt is like the hotspot of phenomenons and ancient science....


Quote Quote by HallsofIvy View Post
No, lightning has nothing to do with "anti-matter".
hmm...check this article...

http://www.ens-newswire.com/ens/jan2...-01-18-01.html

and this one...

http://news.nationalgeographic.com/n...science-space/

Direct quote - "But the lightning flash detected by Fermi appeared to have produced about 100 trillion positrons: "That's a lot," he said"

Looks like it does have something to do with anti-matter.
lpetrich
#18
Jan31-11, 07:40 PM
P: 530
Electric-potential differences can be huge -- they can go to 100 million volts or more. That's more than enough to produce electron-positron pairs.


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