Antimatter black-holes: possibilities/consequences

[lawcat]

I still do not understand, aside from CraigD's post in a one of the threads, how do we get from opposite nature of quantum electrodynamics of antimatter to opposite behavior of antistars or antiplanets. It seems to me that even though the standing wave function, such as spin and orbital, are opposite in antimatter compared to matter, an antistar that would form from quantum interactions would be indistinguishable from a regular star of pertinent properties as far as gravitational well goes. Then, the antimatter blackhole, if one should exist, should be indistinguishable from a matter blackhole as well.

In other words, to presume that matter/antimatter distinction has a relation to gravitational pull is to say in essence that a spin of a black hole has some rational relationship to what falls in. My understanding, albeit limited, is that once there is a well, everything falls in. To the extent that some matter may colide with antinmatter in the abyss there will be annihilation. True?

Since balck hole has three pertinent characteristics: mass, momentum, and charge; and since mass really means energy; then, is there really antimass, antienergy, or anticharge that would make a difference?

[Qfwfq]

Symmetry principles are fundamental to physics. Matter and antimatter have the same energy-momentum tensor. The conjecture that an atom and anti-atom gravitationally repel each other would be such an egregious contradiction of the equivalence principle that, although I don't think it has been specifically tested, I find it hardly conceivable. Even trying to think of writing the field equation with the energy-momentum tensor split into that of matter and that of antimatter doesn't seem to work; offhand I think it would lead to some reductio ad absurdum.

[modest]

I believe there has been some work done on it,

 

Accelerated expansion and time reversal symmetry in general relativity

 

The effects of space-time reversal (PT), proper time reversal (τ → - τ), and charge reversal (q → - q) are examined in the context of general relativity. The results imply accelerated repulsion between matter with past-pointing 4-velocity and matter with future-pointing 4-velocity. Past-pointing matter is thus proposed as a “dark energy” candidate...

 

If the predictions of general relativity regarding past-pointing matter are as accurate as the

more commonly considered aspects of the theory, gravity must have expelled most τ – matter to cosmological distances.

 

http://arxiv.org/ftp/gr-qc/papers/9906/9906012.pdf

 

Gravitation, C, P and T symmetries and the Second Law

 

The intimate links between gravitation and the second law are summarized and two less known relations between gravity and thermodynamics are studied. Firstly, the information cost required to operate a Maxwell’s demon on a curved spacetime is estimated using the Kolmogorov-Sinai entropy. More importantly, the charge and time (C and T) reversal properties of the Kerr-Newman solution in General relativity show that this solution, similarly to the Dirac equation, appears to represent both a particle and its antiparticle and suggests a definition of antimatter in general relativity. This definition leads to a parameter free explanation of the cosmological constant term observed in the supernovae data. The relation of this definition of antimatter with the coupled systems through opposite time arrows studied by Schulman is also emphasized.

 

http://arxiv.org/PS_cache/arxiv/pdf/0804/0804.4199v1.pdf

 

Space-time reversal, antimatter, and antigravity in general relativity

 

Large scale matter-antimatter symmetry and repulsive gravitational interaction between matter and antimatter is proposed as an hypothesis to explain the recent observation of a speed-up of the expansion of the universe. In such a cosmological model the net force on the universe is repulsive even with a cosmological constant equal to zero. A reinterpretation of the meaning of space-time reversed solutions in general relativity suggests the possibility of repulsive gravitational interaction between matter and antimatter.

 

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

 

It's so far over my head I just don't know how serious to take it.

 

~modest

[Hasanuddin]

I still do not understand, …, how do we get from opposite nature of quantum electrodynamics of antimatter to opposite behavior of antistars or antiplanets.

I believe your conflict can be resolved by replacing the word “opposite” with the word “mirror.” This subtle change allows for your later (rebuttal) conclusion, that I am in agreement with

… an antistar that would form from quantum interactions would be indistinguishable from a regular star of pertinent properties as far as gravitational well goes.

Yes, I believe you are correct. AMBH would similarly affect neighboring antimatter in an antimatter galaxy in an indistinguishable fashion to how matter-based black-holes affect the matter in a galaxy such as our own. Remember, the notion of gravitational repulsion is only between opposites; matter/matter interaction would be expected to be mirror-identical to antimatter/antimatter interactions.

 

After this point your post seems to become a bit clouded and jumbled. There is however a possible misconception that is also appearing in other posters’ replies. The question has to do with the “information” of the pre-compacted material after it has been accreted. The simplified version of this was summed up

Black holes are said to destroy information, ie they only keep the bare minimum of information of what they have sucked in.

This all refers back to that “No-hair theorem” (okay Modest, theorem it is, I just feel that in modern usage of words that term gives an unearned “feeling” of absolute completeness, of which we should all remain skeptical until physically proven.) In other words, according to this concept, the only expected informational traits that a black-hole will retain of the material consumed are mass, charge, and angular momentum. Okay, cool, lets just assume that to be true and work with it.

 

What is mass? This is a basic, but not an idle, question. The knee-jerk answer is mass is matter. However, to answer the question that way is the same as saying, “Charge is positive.” Although the statement is true, it is ludicrous in its incompleteness. Mass, just like charge, comes in two types: matter and antimatter.

 

Therefore, if mass information is retained, a black-hole formed from matter would retain this information. Similarly a black-hole formed from antimatter would retain that information. Correct?

 

Therefore if mass information is retained after accretion, then AMBH formed from antimatter would be distinguishable from matter-based black-hole. This assertion is made using essentially the same logic as was earlier proposed to envision a highly charged black-hole, if and only if, it accreted more of one type of charge than another. Please reexamine that conversation

I only truly agree with only one sentence here. It is also the only sentence that was presented categorically, “Black holes will suck in all sorts of matter like electrons and protons, if it sucks in more electrons the black hole will have a net negative charge.” Ya, but so what? Under what conditions would a black-hole be sucking up more electrons than protons? Where does such a charge imbalanced section of the galaxy or Universe exist.

Essentially, I am presenting a nearly identical scenario—which is also compliant to no-hair predictions—but using the variable of mass rather than charge. The biggest difference between the two scenario is that for the Dominium case, I have presented a logistical scenario of how conditions would have developed to create regions predominantly of either matter or antimatter that could have lead to either AMBH or matter-based ones.

 

The biggest of all questions is does matter and antimatter gravitationally attract or does it repel? Keep your fingers crossed and the folks at AEgIS could have our answer before the year is done.

[Moontanman]

A question, since positive and negative charges attract each other why would you expect positive and negative mass to repel each other?

[Hasanuddin]

Hi Moontanman,

 

Please refer to the threads: http://hypography.com/forums/alternative-theories/19536-the-dominium-model-part-2-a.html and http://hypography.com/forums/alternative-theories/18910-the-dominium-model-by-hasanuddin.html

If you still have questions, post them there. Let's stay focused on AMBH, no-hair theorem, or related topics on this thread.

 

edit: I don't mean to be rude, but this conversation is very interesting. Post 21, which you capped, presents a very profound challenge. I would like that challenge to be fully considered

[Jay-qu]

Sorry, but I only truly agree with only one sentence here. It is also the only sentence that was presented categorically, “Black holes will suck in all sorts of matter like electrons and protons, if it sucks in more electrons the black hole will have a net negative charge.” Ya, but so what? Under what conditions would a black-hole be sucking up more electrons than protons? Where does such a charge imbalanced section of the galaxy or Universe exist. Sorry, but I am not partial to hypotheticals that do not exist in nature or could not be reproduced.

 

After that point, I agree with nothing, again because the conditions do not fit with what anyone would expect from nature. “An antimatter black hole may have sucked in positrons and negatrons, if it sucked in more positrons the black hole will have a net positive charge.” {First, by negatrons you mean “antiprotons,” correct? Let’s just stay with traditional definitions for everyone following along.} Secondly, again, why should there be a charge imbalance to set this hypothetical up in the first place?

 

The last part of this post is pure fantasy. You take you two charge-imbalanced black-holes that you fancifully created in two exotic unknown and unspecified regions of the Universe. Now, suddenly, you move these to objects within range of each other? How? We can’t consider your conclusions until you can show us why/how conditions are set.

 

Firstly I apologise for the incorrect word for antiprotons, my mistake.

 

What you have tried to say in rebutting my post is completely false. The laws of physics do not care about the improbability of such situations. It is not a matter of this being unrealistic, it only matters that what I proposed is allowed by the laws of physics and is thus a valid example.

 

What I have done is called a thought experiment. I like how you attempt to speak for everyone with "we cant consider your conclusions until you can show us why/how conditions are set" mm Im sure that is a very commonly used method of rebuttal in peer reviewed science. It is equivalent to saying 'since performing said experiment is impractical (NOT impossible) all else you have said must be ignored'. Thats just pure ignorance.

[Jay-qu]

Hasanuddin you are making claims that are not only unsupported but also go against the common wisdom of physics - namely: "Mass, just like charge, comes in two types: matter and antimatter."

 

As has been said before, matter and antimatter have opposite charges - mass is NOT a charge and in our conventional models is the same for both matter and antimatter. This means that matter and antimatter attract each other gravitationally. Gravity is a fundamentally attractive force, it does not act in the opposite way - this is consistent with all observations.

[lawcat]

I believe there has been some work done on it,

 

It's so far over my head I just don't know how serious to take it.

 

~modest

 

Thanks again Modest. Your post was of great help. Do you read Ripalda's paper like this: Ripalda takes Lorentz factor - Wikipedia, the free encyclopedia, and mathematically deduces that the square root in denom produces negative and positive Lorentz factor reuslts. Then, Ripalda concludes if Lorentz factor can be positive and negative, then the proper time direction can be positive and negative. Next, Ripalda concludes that such sign change demands the change in sign of momentum and mass. This change to Ripalda means that the stress-energy tensor can be positive and negative; a proof, in accordance with Einstein's field equations that antimatter gravity is negative, whereas matter gravity is positive. But, Ripalda prefaces all this with the statement that the signs here are not intrinsic properties but depend on the motion.

 

Chardin invokes Berkenstein-Hawking, and Kerr-Newman's formula's to argue that such antigravity is consistent with the universal prinicple of increasing entropy.

 

So, in those three papers, we go from QED to SR to GR to 2nd law, in a mathematically consistent way?

But everything rests on Lorentz factor being negative or positive. Is that a valid physical assumption? Can it be applied to say that mass and stress-energy tensor can be negative and positive?

[Qfwfq]

Imagine some source is spewing out ions and the process involves a magnetic field that separates them into a positive and negative jet. A highly massive object somewhere in the neighbourhood might be invested by one of the two jets. Not so absurd after all.

 

It's so far over my head I just don't know how serious to take it.

Yes it's not a simple matter, but I really just loved the drawing of Maxwell's demon!

 

A question, since positive and negative charges attract each other why would you expect positive and negative mass to repel each other?

From the fact that, contrary to like electric charges, masses attract and don't repell each other.

 

Your point the other day about photons had a tacit assumption, of mutual attraction being a transitive property. While this makes your argument inconclusive (as you put it), your mention of the fact that some particles coincide with their antiparticles gave me a good hint toward finding a reductio ad absurdum that I think probably follows. :D The simplest way to put it is that, on one hand, the photon must be attracted to both because it is both and, otoh, it must be repelled by both because it is the opposite of both. This contradiction could only be resolved if it were not deflected at all, contrary to what we observe.

 

In any case I went to bed pondering about the effect the conjecture would have on existing data. Considering that the fields in the structure of different materials ought to have differing content of virtual pairs in their Fock spaces, one might work out what kind of deviations to expect from the equivalence priniple applied to the overall material; this is the same kind of reasoning used for testing the principle for the different fundamental interactions. The virtual pairs would be "missing mass" regarding gravitaional attraction, but are certainly not missing inertial mass. A carefully conducted quantitative computation for materials on which the principle has been tested might even settle the matter already.

[Hasanuddin]

Hasanuddin you are making claims that are not only unsupported but also go against the common wisdom of physics - namely: "Mass, just like charge, comes in two types: matter and antimatter."

 

As has been said before, matter and antimatter have opposite charges - mass is NOT a charge and in our conventional models is the same for both matter and antimatter. This means that matter and antimatter attract each other gravitationally. Gravity is a fundamentally attractive force, it does not act in the opposite way - this is consistent with all observations.

Actually, nothing in what I am saying conflicts with heart-felt truths of physics. Perhaps I used the wrong hinge-word in the statement you’ve quoted. I agree “types” is borderline incorrect, though “expressions” would be much more accurate and descriptive of my point:

 

There are two expressions of charge; there are two expressions of mass.

How’s that? I don't believe there is anything new in making that statement. Given the no-hair theorem, and given the correctness of the above statement, I stand by the assertiong that:

 

1. The only information retained by something accreted in a black-hole are mass, charge, and angular momentum.

2. The two expressions of mass are as either matter or antimatter

3. Therefore, AMBH will retain signature aspects of being antimatter, & v.v.

 

This quote goes on to argue (it appears) that the only difference between matter and antimatter is reversed charge, a belief that it “goes against the common wisdom of physics.” If this were true, there should be no annihilation events between matter and antimatter, because there are no annihilation events between common collisions of common oppositely charged particles. Please reconcile.

 

Lastly, the above quote concludes by proclaiming prior-knowledge the exact outcome of the AEgIS experiment before those results are published. WELCOME TO AEgIS It is fine to have opinions, but please be sensitive to areas that are still unknown. The gravitational relationship between matter and antimatter is still an unknown. Therefore, for this discussion we need to be able to discuss both options with a degree of skepticism that leaves alive the other option. Once AEgIS weighs in, the conversation should move more one-sidedly (assuming and hoping that AEgIS gives conclusive results.)

[Qfwfq]

Actually, nothing in what I am saying conflicts with heart-felt truths of physics.

Who accused you of contradicting your own belief?

 

Anyway, physics is not a religion; truth in physics is not what you feel in your heart. This is a science forum and has some rules, odd claims must be supported.

 

This quote goes on to argue (it appears) that the only difference between matter and antimatter is reversed charge,

The quote does not say that. It does not even appear to state it being the only difference.

 

Lastly, the above quote concludes by proclaiming prior-knowledge the exact outcome of the AEgIS experiment before those results are published.

This is nitpicking, it's obvious he meant well known observations, which doesn't include unpublished results.

[modest]

Your post was of great help. Do you read Ripalda's paper like this...

 

thank you. I don't feel qualified-enough or informed-enough about the papers to comment on what you said. If I have time to look at them in detail I might get back to you. Sorry.

 

Your point the other day about photons had a tacit assumption, of mutual attraction being a transitive property. While this makes your argument inconclusive (as you put it), your mention of the fact that some particles coincide with their antiparticles gave me a good hint toward finding a reductio ad absurdum that I think probably follows. :D The simplest way to put it is that, on one hand, the photon must be attracted to both because it is both and, otoh, it must be repelled by both because it is the opposite of both. This contradiction could only be resolved if it were not deflected at all, contrary to what we observe.

 

Good point. Craig also brought up the issue in regards to gluons,

 

Consider, by way of explanation, that most of the mass of ordinary matter is not due to particles that are not their own antiparticles – quarks and electrons – but due to gluons. For example, for an atom of hydrogen, each of the 2 U quarks in its proton mass about 3 MeV, the 1 D quark about 6, its electron about 0.5, and the gluons binding the 3 quarks together about 926, so about 97% of its mass is in the form of gluons, a ratio roughly the same for all atomic matter. For atomic matter to gravitationally attract atomic matter, but repel atomic antimatter, the anti-gluons in antimatter must gravitationally interact differently than the gluons in matter. However, as gluons and anti-gluons are the same particle in the Standard Model, they can’t.

 

I would wonder... does the Higgs mechanism give mass to photons or gluons?

 

~modest

[Jay-qu]

Your point the other day about photons had a tacit assumption, of mutual attraction being a transitive property. While this makes your argument inconclusive (as you put it), your mention of the fact that some particles coincide with their antiparticles gave me a good hint toward finding a reductio ad absurdum that I think probably follows. :) The simplest way to put it is that, on one hand, the photon must be attracted to both because it is both and, otoh, it must be repelled by both because it is the opposite of both. This contradiction could only be resolved if it were not deflected at all, contrary to what we observe.

 

Beautiful argument - Hasanuddin I would like you to comment on what you think about the above quoted text by Qfwfq.

 

Actually, nothing in what I am saying conflicts with heart-felt truths of physics. Perhaps I used the wrong hinge-word in the statement you’ve quoted. I agree “types” is borderline incorrect, though “expressions” would be much more accurate and descriptive of my point:

 

There are two expressions of charge; there are two expressions of mass.

How’s that?

Physics does not care about what word you ascribe to properties of matter. Physics is invariant with respect to lexical transformations - so I dont care if you call them 'whosathingoes' it doesnt change your initial argument.

This quote goes on to argue (it appears) that the only difference between matter and antimatter is reversed charge, a belief that it “goes against the common wisdom of physics.” If this were true, there should be no annihilation events between matter and antimatter, because there are no annihilation events between common collisions of common oppositely charged particles. Please reconcile.

Well then to solidify the argument of the middle sentence, provide me with experimental evidence of a case when particles with opposite charges do not annihilate each other - and I dont just mean opposite electric charges, I mean all charges being opposite.

Lastly, the above quote concludes by proclaiming prior-knowledge the exact outcome of the AEgIS experiment before those results are published.

Not it does not, and it is not just my opinion but many. I am happy to be wrong when shown proof to the contrary. I am only saying that many people have the intuition that matter and antimatter do not have 'opposite' mass.

 

Good point. Craig also brought up the issue in regards to gluons,

 

I would wonder... does the Higgs mechanism give mass to photons or gluons?

 

~modest

 

The Higgs does not couple with the photon or gluons, therefore these bosons remain massless.

[Hasanuddin]

With regards to photon interaction to black-holes (AMBH or matter-based) the following discussion was asserted.

Your point the other day about photons had a tacit assumption, of mutual attraction being a transitive property. While this makes your argument inconclusive (as you put it), your mention of the fact that some particles coincide with their antiparticles gave me a good hint toward finding a reductio ad absurdum that I think probably follows. The simplest way to put it is that, on one hand, the photon must be attracted to both because it is both and, otoh, it must be repelled by both because it is the opposite of both. This contradiction could only be resolved if it were not deflected at all, contrary to what we observe.

The problem is that a reductio ad absurdum is not actually reached because prevailing truths are ignored. Specifically, the line it (photons) must be repelled by both because it is the opposite of both. This is an absurd premise, not an absurd conclusion. It is an established truth that light display attraction to known matter-based black-hole. When using an absurd premise, the consequence that the resulting conclusion is also absurd to be expected and is irrelevant to the issues being discussed. Rather that making up scenario that are easily brushed aside (strawman), please address the actual syllogism put forward:

 

a. Light is the antiparticle of itself

b. As the antiparticle of itself it will be expected to feel the same types of stimulus as it does from particles, as it does from their equivalent antiparticles

c. Light is observed to be attracted to matter-based black-hole

Therefore, light is expected to be observed attracted to AMBH

 

Folks, please let us focus on the science and logic. To chastise my wording, yet not to respond to the message being delivered is a waste of all of our time. For example, within this thread I brought up a very basic, yet very profound question, “What is mass?” To my first attempt to define how matter and antimatter fit into that question. I said “Mass, just like charge, comes in two type: matter and antimatter.” In response

As has been said before, matter and antimatter have opposite charges - mass is NOT a charge and in our conventional models is the same for both matter and antimatter.

This assertion was questioned by myself saying, “This quote goes on to argue (it appears) that the only difference between matter and antimatter is reversed charge, a belief that it “goes against the common wisdom of physics.” To that Qfwfq injected on Jay-qu’s behalf

The quote does not say that. It does not even appear to state it being the only difference.

My request is this, if you feel that misunderstandings are occurring, please clear them up. To condemn my words, yet give no explanation for your views is not fair to me or anyone else trying to read along.

 

Though I tried to clear up matters by redefining my assertion for the relationship of mass, matter, and antimatter saying, Perhaps I used the wrong hinge-word in the statement you’ve quoted. I agree “types” is borderline incorrect, though “expressions” would be much more accurate and descriptive of my point: There are two expressions of charge; there are two expressions of mass.

The only response forthcoming was

Physics does not care about what word you ascribe to properties of matter. Physics is invariant with respect to lexical transformations - so I dont care if you call them 'whosathingoes' it doesnt change your initial argument.

Again, please address the issues. If you do not feel that the statement advanced is correct… then please rebut the science, set the record straight, and show/elaborate what the actual dynamic is.

 

Later on in this post, Jay-qu tried to turn the tables by redefining the argument. The argument posited related the known dynamics of all types of electrostatic systems to the partially documented dynamics of gravitational systems. The expressions of mass vs the expressions of electric charge were on that table. I had also posited that the problem of simplistically stating that antimatter is the same as matter, but the electric charges are reverse (as Jay-qu appeared to do in the 1st quote above) is that annihilation events cannot be explained. To that assertion came this table-turning reply

provide me with experimental evidence of a case when particles with opposite charges do not annihilate each other - and I dont just mean opposite electric charges, I mean all charges being opposite.

First of all, the burden of proof in on Jay-qu to reconcile his first statement with the known occurrence of annihilation events. Secondly, and most importantly, everything that I have advanced up to this point regarded electric charges. I know of only two expressions of charge, + & -, if there are more, that’d be news to me, but I’d be interested. Please Jay-qu elaborate your points. How can one say that matter and antimatter are charge inversions of each other, yet not account for stable electrostatic systems vs known annihilation of matter and antimatter?

[Jay-qu]

Of course the burden of proof is on me.. god forbid you be required to show all of the physics community why we are wrong, instead we must show every person with a physically unfounded hypothesis why they are wrong. Sorry thats not how the science community works. If you have a strange claim you show the proof.

 

Now if you can get off your high horse for a minute and actually address the issues we raise in our posts, instead of attempting to insult us by saying we are ignoring your real concerns. It is you that keeps ignoring flaws that we are raising in your arguments.

 

It is a rule of this site that you must present evidence (in the form of a link or document) of any claims that you make in your posts. So again, as I asked you above please provide some experimental evidence of a case when particles with opposite charges do not annihilate each other - and I dont just mean opposite electric charges, I mean all charges being opposite.

 

I ask this because your earlier post hinges on providing this proof, to cast this aside and ignore it would be allowing your incorrect posts on our site to go unchecked or unchallenged.

[Hasanuddin]

Jay-qu,

 

The last post in this series is way too emotional. On one hand you accuse me of insulting you—this is a misunderstanding for I never intended any personal offense. If you do find something I said abusive, then please quote such foul words so that I might apologize or explain. In the very next breath you use words such as “unfounded,” “strange,” and the phrase “get off your high horse” … yet you never elaborate what exactly is so distasteful to you. Let us try to start afresh. In this post I will reiterate the syllogistic points that I am making. If there is a flaw, please highlight such areas so that we may have a meaningful discussion.

 

On this thread I have actually only attempted to present two lines of thought:

RE: AMBH and no-hair

A: No-hair theorem predicts that the only information retain from material compacted into black-hole material are mass, charge, and angular-momentum

B: Charge comes in two different expressions

C: Therefore, scientists believe that a black-hole consuming an imbalance of charge, say “positive,” will result in a black-hole retains that information and would exhibit dynamics of being net “positive.”

D: Mass is displayed via two different expressions

E: Therefore, given “C” we should believe that a black-hole consuming an imbalance of one expression of mass, say antimatter, will exhibit dynamics of being net antimatter.

RE: Light interaction with AMBH

A: Light is the antiparticle of itself

B: Therefore photons have as much in common with particles as they do with their equivalent antiparticles

C: Light has been observed to bend (attractively) as a result of the influence of matter-based black-hole

D: Therefore, light would be expected to bend (attractively) as a result of the influence of AMBH

 

Please, if there are issues/concerns with either of these lines of reasoning, please introduce them to this discussion.

 

Tangentially related to this thread, but also discussed, are the interactions of matter with antimatter. Though such discussions are more appropriate for either of the two Dominium threads,

http://hypography.com/forums/alternative-theories/18910-the-dominium-model-by-hasanuddin.html

http://hypography.com/forums/alternative-theories/19536-the-dominium-model-part-2-a.html

However, if one feels it necessary and relevant to this conversation, so be it. I only set forward one request: that all viable options be considered. In this case that means simultaneously discussion both paths, gravitational-repulsion & universal-attraction. This request is a result of the following reasoning.

RE: Potential gravitational dynamics of AMBH

A: No understanding exists for the actual gravitational interaction between matter and antimatter (the AEgIS experiment will be the first to weigh in on this question, but results are not yet out.)

B: Therefore, when considering questions where matter, antimatter, and gravity all play roles, then we must consider both paths (gravitational repulsion & universal attraction.)

C: AMBH, theoretically, have the potential of interacting with matter

D: Therefore, when discussion such potential interactions, both paths (gravitational-repulsion & universal attraction) need to both be considered and discussed.