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If there were equal amounts of matter and anti-matter in the universe, it would be easy to deduce that the universe has a net charge of zero, since a defining ‘opposite’ of matter and anti-matter is charge. So if a particle has charge, its anti-particle will have an equal but opposite charge. For example, protons have a positive charge – while anti-protons have a negative charge.
But it’s not apparent that there is a lot of anti-matter around as neither the cosmic microwave background, nor the more contemporary universe contain evidence of annihilation borders – where contact between regions of large scale matter and large scale anti-matter should produce bright outbursts of gamma rays.
So, since we do apparently live in a matter-dominated universe – the question of whether the universe has a net charge of zero is an open question.
It’s reasonable to assume that dark matter has either a net zero charge – or just no charge at all – simply because it is dark. Charged particles and larger objects like stars with dynamic mixtures of positive and negative charges, produce electromagnetic fields and electromagnetic radiation.
So, perhaps we can constrain the question of whether the universe has a net charge of zero to just asking whether the total sum of all non-dark matter has. We know that most cold, static matter – that is in an atomic, rather than a plasma, form – should have a net charge of zero, since atoms have equal numbers of positively charged protons and negatively charged electrons.
Stars composed of hot plasma might also be assumed to have a net charge of zero, since they are the product of accreted cold, atomic material which has been compressed and heated to create a plasma of dissociated nuclei (+ve) and electrons (-ve).
The principle of charge conservation (which is accredited to Benjamin Franklin) has it that the amount of charge in a system is always conserved, so that the amount flowing in will equal the amount flowing out.
An experiment which has been suggested to enable measurement of the net charge of the universe, involves looking at the solar system as a charge-conserving system, where the amount flowing in is carried by charged particles in cosmic rays – while the amount flowing out is carried by charged particles in the Sun’s solar wind.
If we then look at a cool, solid object like the Moon, which has no magnetic field or atmosphere to deflect charged particles, it should be possible to estimate the net contribution of charge delivered by cosmic rays and by solar wind. And when the Moon is shadowed by the tail of the Earth’s magnetosphere, it should be possible to detect the flux attributable to just cosmic rays – which should represent the charge status of the wider universe.
Drawing on data collected from sources including Apollo surface experiments, the Solar and Heliospheric Observatory (SOHO), the WIND spacecraft and the Alpha Magnetic Spectrometer flown on a space shuttle (STS 91), the surprising finding is a net overbalance of positive charges arriving from deep space, implying that there is an overall charge imbalance in the cosmos.
Either that or a negative charge flux occurs at energy levels lower than the threshold of measurement that was achievable in this study. So perhaps this study is a bit inconclusive, but the question of whether the universe has a net charge of zero still remains an open question.
Further reading: Simon, M.J. and Ulbricht, J. (2010) Generating an electrical potential on the Moon by cosmic rays and solar wind?
It could be a shocking situation if the net carge wasn’t zero. 😀
Of course we all know that the universe is quasi-neutral. But there are two very different issues here. (1) Matter vs anti-matter (2) Positive vs negative charges. I’m guessing that the article is derived from a report on Matter/antimatter Asymmetry, see:
* Tantalizing Clues as to Why Matter Prevails in the Universe: Surprisingly Large, ScienceDaily (Aug. 17, 2010) , in turn based on:
* “A new source of CP violation?“, Physics 3, 69 (August 16, 2010)
In 1959 Herman Bondi and R.A. Lyttleton proposed of “The possibility of a general excess of charge in the universe”. See “On the Physical Consequences of a General Excess of Charge” ( Proc. R. Soc. Lond. A 29 September 1959 vol. 252 no. 1270 313-333). This is not an endorsement.
I expect that the “Electric Universe” brigade will be wetting their knickers over this for all the wrong reasons!
I wonder whether CP violation occurs in an anti-matter universe in such a way as to balance the apparent asymmetry?
a molecule in the vacuum state will not have electrons in the ground state or lowest energy level. Excited electrons form electron holes, which are like positively charged black holes. Instead of anti-matter counterparts for electrons and positrons, the conceptual and mathematical opposite of an electron is the electron hole responsible for most acquired mass. If a vacuum state is filled with an electron, it becomes an electron, otherwise its vacuum state is treated as a positive charged particle such as when helium when losing an electron forms a hydrogen atom with a electron hole.
Fully symmetric Maxwell equations require a magnetic charge current density variable, allowing for either magnetic or electric charges, instead of standard zero magnetic charge. All particles have tiny magnetic fields, and Zweibel says the intergalactic magnetic fields lower bound is at least one ten million billionths earth’s strength, and not even associated with any galaxy or clusters suggests a primordial and fundamental magnetic field for the universe. Magnetic Monopoles are particles having one magnetic pole, that black hole singularities can explain. Large Mass black holes in natural units equal their Charge !
Einstein wrote papers that a black hole has the same mass and charge as an electron. A black hole has an event horizon where light cannot escape its gravity unobservable from the outside, but an electron black hole is a naked singularity observable from the outside without an event horizon where light escapes, and perhaps was Einstein’s EM white hole or wormhole?
the theory of everything and our desire to conquer overcome learn the truth behind the self-inherent ignorance of existance, and obtain all knowledge of everything the universe like God almighty while still alive as a being in Christ, not instead a buncha atoms and death forever as the 2nd law of TD sadly leads…amen
The total electric charge is probably zero. Imagine a positively charged particle. The electric flux lines radially diverge away (in fact involves something called the divergence theorem of Gauss) and end at some negative charge. If the number of positive and negative charges are equal then all these flux lines exit a + charge and enter a – charge. What would happen if there was an excess of some charge, say + charge. The electric flux lines would diverge and define some sort of data “at infinity” for a spatially flat universe, or if the universe were a three dimensional sphere the flux lines would wrap around almost endlessly. Both of these are problems. For the flat universe if would mean some sort of auxiliary data is required that is problematic. For the closed spherical universe things are worse. The endless wrapping of the field lines around the universe would set up an infinite energy density in the universe.
LC
does this include the messenger?
Right, an interesting set of questions (charge symmetry breaking, baryon symmetry breaking) and an interesting observation.
First, there is a lot of assumptions made specifically on the Moon model.
Second, I find the paper’s analysis confusing, as they conflate a lot of issues.
That cosmic rays (CR) are mostly protons and so charging isolated bodies isn’t new. That doesn’t imply that there was a baryon, lepton or charge asymmetry in the originating volume, it means that the CR production process isn’t charge neutral.
That CR charging doesn’t happen to high potentials can be observed in solar system bodies interactions I believe. (Whether or not the highly energetic CR flow should be integrated with the remaining fermions to a, implicitly suggested collisionless I think, “plasma”. Probably not, AFAIU CR-CR spallation is observed. The universe is _huge_.) More precisely there are probes that should have rejected the opposite.
The paper concludes with a wild proposal of electromagnetic interaction to the vacuum. Pure EU universe stuff, IMHO.
On the other, as seen twice (production, actual charging) unrelated question: Classically fields can’t be net charged to infinity in a flat universe. I see LBC covered that. Caveat that inflation disconnects observable universes from that requirement, so our observations could differ.
While I’m not up to Noether’s theorem and what it says on charge conservation and symmetry breaking, it is IMHO interesting that FRW universes globally must obey all field symmetries and spacetime time-energy symmetry (zero energy universes) to work. Simplicity at the helm!
The net charge of cosmic rays (galactic, not counting solar or anomalous) may be positive, in some accounting, but extraordinary care needs to be taken with this (my comments are related to TL’s “That cosmic rays (CR) are mostly protons”).
Electrons, and antiprotons, are likely to have far shorter mean free paths through the galaxy than protons (or heavier nuclei), and to lose their energy far faster than protons (due to scattering, etc). That doesn’t stop them from wandering the galaxy, much as most CRs do (think “galaxy as a leaky box”), so there is, very likely, some netting of charge.
So where do the de-fanged electrons go? Some, no doubt, do continue as low energy CRs (do such CRs exhibit a net negative charge? I don’t know, and I don’t know if anyone has looked closely enough); others no doubt simply become part of the ISM, and one day interact with the heliosphere …
While high energy CRs are certainly sexy, in terms of total CR charge they are trivial; low energy CRs vastly outnumber the sexy ones.
a huge thumbs down to IVAN3MAN for yet again attempting to troll the EU theory debate into this post.
get a life dude.
My reading (admittedly, I skimmed the article) was not so much that they were suggesting the universe as a whole has a net [excess] of any sign (+ or -) of charge, so much as that while the universe may be on the whole (averaged over its entire volume, be that finite or infinite) composed of equal and opposite charges, but that localized regions can become “out-of-balance” (or charged) WRT other regions.
That is to say, a planet or moon or star or satellite can acquire an excess of charges of one sign or the other (we know satellites in Earth orbit can acquire, I believe, a non-trivial negative charge) with respect to surrounding space.
If that be so, and individual objects can become, for instance, positively charged, does that mean that other adjoining regions will become charge depleted (thus equally and oppositely charged)? As an off-the-cuff example, if a satellite acquires a negative charge / potential, would the surrounding space charge then be at a positive charge / potential?
Again, it seems to me that what is suggested here is NOT that the universe “as a whole” has an excess charge, but that individual regions can acquire a non-trivial electric charge, thus violating substantially the notion of a purely electrically neutral universe. That is to say, the action of the electric fields generated between charged bodies (or charge-depleted / oppositely-charged bodies) should not be ignored out of hand.
At least that was my reading from a quick skim of the article.
1) On the whole, equal and opposite charges are probably the rule.
2) Locally, charges may become and remain unbalanced, requiring consideration of the electric force in local and potentially (pun intended) cosmological models.
Keeping in mind that Alfven’s CIVs (Critical Ionization Velocities between plasmas and “neutral” matter) and DLs (Double Layers or plasma sheaths) may play roles in such ionization, separation of charges and the maintenance of such separation, among other things.
@CAPPER,
Your accusation is known as “Shooting the messenger“; those EU/PC nuts would have turned up regardless, without me mentioning them!
@MGMIRKIN: wrt “Keeping in mind that Alfven’s CIVs (Critical Ionization Velocities between plasmas and “neutral” matter) and DLs (Double Layers or plasma sheaths)”.
As far as I know, no astrophysical examples of CIV have ever been found; certainly Verschuur’s work didn’t turn up any (when you look at the whole relevant literature, not just a careful selection of his papers).
DLs are very tricky things; the situations in which they can occur are not as common as you might think, and their role in “such ionization, separation of charges and the maintenance of such separation, among other things” isn’t straight-forward at all. On top of that, what we can observe, in astronomy (beyond the solar system), and infer is magnetic fields (electric fields, unless quite intense, are essentially invisible). But never mind, as long as the astrophysical models faithfully represent the relevant plasma physics, you can work out at least some parameters of any electric field if you want to. Of the thousands of recent published papers with plasma physics-based astrophysical models, which do you consider to be problematic?
Re cosmology: I’m not sure if you saw my earlier comment about CRs and the galaxy being a ‘leaky box’ (did you?), but I can’t see how this paper has any relevance to cosmology.
A symmetric electromagnetic model with a magnetic monopole is of course explored. The Dirac monopole string is a way of trying to construct such a theory. The electric charge q and the magnetic monopole charge turn out to be related to each other by the Bohr-Sommerfeld relationship
qg = n-hbar
for n an integer and hbar the unit of action. This in a general setting plays a role in something called S-duality in string theory. However, for practical considerations there are not magnetic monopoles. Magnetic fields exist in dipoles.
If the universe had a net charge, and by analogy a net angular momentum, there would be a BPS term that would lead to pathologies. In particular the universe would have closed timelike curves and various causality violating effects.
LC
@mgmirkin
You are assuming that when a satellite or space object gets bombarded by a charge that the charge will stay there forever.
Charge repels each other so when there is a big build-up of a certain charge then more and more charge gets ejected over a period of time.
Yes and I have to add to my last post. An object that gets a certain charge will also repel more and more incoming charge so the increase of charge stops at a certain level and as long as it get bombarded with that charge.
Mirror mirror, on the wall, is your symmetry about to fall?
How can matter then be thrust past holes in reality’s polar trust?
Symmetrical synthesis a central glow of our galaxy’s torus material flow!
Monopole magnets so hard to figure behind momentum’s nuclear trigger?
Gravity holds us to the Earth so dear, our magnetic field holding back Sol’s tears.
Mirror mirror, on the wall, what is it that we seek to make our species tall?
…or something like that…. ~@; )
It appears that some individuals here (mention no names) are smoking crack!
@all
Thanks for some very insightful comments.
I liked the ambitious scale and scope of this ‘experiment’ – the many assumptions required to make it work is not that unusual in theoretical cosmology. I thought the conclusion about maybe missing low energy negative inputs a noteworthy (and testable) finding.
But, like TL OM, I found the alternative suggestion of charged objects interacting with the vacuum a bit out of left field (and not obviously testable – or explained fully). So I didn’t mention that in the write up.
@ mgmirkin
Your skim missed this statement in the abstract: “As the cosmic rays arrive from deep space, these findings would imply a charge imbalance in the cosmos. This is in distinct conflict with a charge neutral universe”.
There is probably a simple reason for why cosmic rays are primarily positively charged. Positive charged species are comparatively massive, where as the electron is light weight and the power of Brehmsstralung emission is proportional to acceleration-squared a^2. By Newton’s second law a = F/m, and for a magnetic force applied to a charge the acceleration is proportional to 1/m^2. Therefore electron emit their kinetic energy far more in the presence of galactic magnetic fields and other magnetic fields. The mass of the electron is about 1/2000 times that of the proton, so the Brehmasstralung power is 4 million times that of protons with the same velocity.
LC
@LAWRENCE B. CROWELL,
Er… one of us here must be tired… according to Wikipedia, electrons lose energy due to bremsstrahlung at a rate of [m(p)/m(e)]^4 ≈ 10^13 times higher than protons do.
(I hope that equation comes out right!)
in this case, there wasn’t even a messenger to shoot. Vanka was just firing blindly into the dark unlit corners of his own personal electric universe fantasy troll.
@ IVAN3MAN_AT_LARGE; I was thinking of the nonrelativistic form of the Brehmasstralung power. For highly relativistic particles the Lorentz factor boosts the rate.
LC
Seems likely to me that a supernova explosion will produce a large amount of aligned positive charged H+ cosmic rays that being light enough leaves the galaxy. The intergalactic medium nearer galaxy clusters is probably denser with H+ cosmic waves. supernova shock waves that travel slightly slower, could carry the lighter negative charges bent by the suns magnetic field.
I’ve, only now, had a chance to go through this paper in some detail. Like Torbjorn Larsson OM, I find it confusing (has anyone else actually read the whole thing?)
I also found the treatment of low energy particles inconsistent, and the possibility of quite local effects at the Apollo 15 site missing.
I rather doubt it it will be published any time soon!
I read this paper through. I find it to have elements of confusion. The problem is that the moon is not at all a good “detector” for whether there is a net charge to the universe. There are too many complicated environmental factors that contribute noise.
LC
Yuk!! Bad Science ….
And there isn’t much to say for the article either. The first paragraph sets the tone with pure tautological baffle-speak.
“If there were equal amounts of matter and anti-matter in the universe, it would be easy to deduce that the universe has a net charge of zero, since a defining ‘opposite’ of matter and anti-matter is charge.”
Which is another way of saying that if the total electric charge in the universe is zero, then the total electric charge in the universe is zero.
How many words does it take to say nothing at all?
@all
To be fair to the authors – it’s on arXiv and is not meant to be a finished product. Perhaps they will find these comments and find them helpful – hope so.
@cometstorm
Bad science is making rash claims without willingly offering your evidence/working up for public scrutiny. You can still do good science, even if someone later demonstrates you got it all wrong through peer review etc.
Re the article, note the sentence starts with “if…” – the point being that there aren’t obviously equal amounts of matter and anti-matter – which is both surprising and means we can’t just assume a net charge of zero.
The article is about whether the net charge is zero – this is not the same as the total charge.
How many words does it take to say nothing at all? Three.
@Steve Nerlich: I think it’s likely to need a very great deal of re-work and additional work before the authors are ready to even think of submitting it to a decent, relevant journal (there are some journals that would take it pretty much as it is, but, to misquote one of the Marx brothers, if I were an author, I wouldn’t want to be published in a journal that would accept a ‘my paper’ like this!). There are a lot more shortcomings than have been mentioned explicitly so far in these comments.