Protons and antiprotons appear to be true mirror images

Protons and antiprotons appear to be true mirror images
A cut-away schematic of the Penning trap system used by BASE. The experiment receives antiprotons from CERN's AD; negative hydrogen ions are formed during injection into the apparatus. The set-up works with only a pair of particles at a time, while a cloud of a few hundred others are held in the reservoir trap, for future use. Here, an antiproton is in the measurement trap, while the negative hydyrogen ion is in held by the downstream park electrode. When the antiproton has been measured, it is moved to the upstream park electrode and the hydrogen ion is brought in to the measurement trap. This is repeated thousands of times, enabling a high-precision comparison of the charge-to-mass ratios of the two particles. Credit: CERN

In a stringent test of a fundamental property of the standard model of particle physics, known as CPT symmetry, researchers from the RIKEN-led BASE collaboration at CERN have made the most precise measurements so far of the charge-to-mass ratio of protons and their antimatter counterparts, antiprotons.

The work, published in Nature, was carried out using CERN's Antiproton Decelerator, a device that provides low-energy antiprotons for antimatter studies.

CPT invariance—which the experiment was meant to test —means that a system remains unchanged if three fundamental properties are reversed—C (charge), which distinguishes matter from antimatter, P (parity), which implies a 180 degree flip in space, and T (time). It is a central tenet of the , and implies that must be perfect mirror images of matter, with only their charges reversed.

"This is an important issue," says Stefan Ulmer, who led the research, "because it helps us to understand why we live in a universe that has practically no antimatter, despite the fact that the Big Bang must have led to the creation of both. If we had found violations of CPT, it would mean that might have different properties—for example that antiprotons might decay faster than protons—but we have found within quite strict limits that the charge-to-mass ratios are the same."

To perform the research, the team used a scheme similar to that developed by the TRAP collaboration in the 1990s. They received antiprotons and negative hydrogen ions—as a proxy for protons—from the Antiproton Decelerator, and then trapped single antiproton-hydrogen ion pairs in a magnetic Penning trap, decelerating them to ultra-low energies. They then measured the cyclotron frequency of the pairs—a measurement that allows scientists to determine the charge-to-mass ratio—and compared them to find how similar they were. In total, they measured approximately 6,500 pairs over a 35-day period.

"What we found," says Ulmer, "is that the charge-to-mass ratio is identical to within just 69 parts per trillion." This measurement has four times higher energy resolution than previous of proton-antiproton pairs, and further constrains the possibility of violations of CPT invariance. "Ultimately," he says, "we plan to achieve measurements that are at least ten or a hundred times more precise than the current standard."

The work also has implications for what is known as the weak equivalence principle—the idea that all particles will be affected by gravity in the same way, regardless of their mass and charge. The team used their findings to calculate that within about one part per million, antimatter and matter behave in the same way with respect to gravity.

According to BASE member Christian Smorra, "There are many reasons to believe in physics beyond the standard model, including the mystery of dark matter and, of course, the imbalance between matter and . These high-precision measurements put important new constraints and will help us to determine the direction of future research."


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Measuring the magnetism of antimatter: Researchers measure antiprotons more accurately than ever before

More information: High-precision comparison of the antiproton-to-proton charge-to-mass ratio, Nature, DOI: 10.1038/nature14861
Journal information: Nature

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Aug 12, 2015
This is an important issue," says Stefan Ulmer, who led the research, "because it helps us to understand why we live in a universe that has practically no antimatter, despite the fact that the Big Bang must have led to the creation of both


Obviously, your calculations are wrong.


Aug 12, 2015
This is an important issue," says Stefan Ulmer, who led the research, "because it helps us to understand why we live in a universe that has practically no antimatter, despite the fact that the Big Bang must have led to the creation of both

Obviously, your calculations are wrong.

However, given that antimatter exists (it can be created in lab conditions), the question of why the universe is one type (or a mix) instead of the other rather obviously presents itself. Apart from actually observing the creation of the universe (good luck with that) to figure out the disparity, how would you suggest this be investigated, and where the researchers' calculations might be wrong, as you claim?

I suggest that there is no "obviously" about it - the calculations may indeed be wrong but I'm certain that this is far from obvious or those same calculations would have had the obvious error(s) corrected.

Aug 12, 2015
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Aug 12, 2015
I suggest that there is no "obviously" about it - the calculations may indeed be wrong but I'm certain that this is far from obvious or those same calculations would have had the obvious error(s) corrected.


What "calculations"? There's nothing in the article about calculating anything, only making "measurements" in the production of anti-matter.

Aug 12, 2015
I suggest that there is no "obviously" about it - the calculations may indeed be wrong but I'm certain that this is far from obvious or those same calculations would have had the obvious error(s) corrected.

What "calculations"? There's nothing in the article about calculating anything, only making "measurements" in the production of anti-matter.

Yes, technically correct however I made an assumption that @Returners was referring to calculations implied in the article end-quote from Smorra about the imbalance of matter and antimatter and the "important new constraints" on the Standard Model. Perhaps I ought to have been more explicit in this; my apologies for the oversight.

Aug 12, 2015
The actual Nature article states 'From 13,000 frequency measurements we compare..obtain (q/m){-p}/(q/m){p}-1=1(69)x10^-12...' So it seems here that the values depended on the observation of the experiment and not just equations. Having said that the equations used in the article are more to do with equipment expectations/measured cyclotron frequencies and this needs to be examined by other experts, that is confirmed and repeated. Whether equipment standards are adequate is something I can't comment on...perhaps someone here can. It is empirical measurements that are being reported and and not a set of theoretical equations and those equations that are there seem to be 'standard acceptable' as used in other trap (one particle) experiments. The part that has always intrigued me is the 'T' in CPT, can we be sure of characteristics of time-reversal. Any ideas?

Aug 12, 2015
I suggest that there is no "obviously" about it - the calculations may indeed be wrong but I'm certain that this is far from obvious or those same calculations would have had the obvious error(s) corrected.


Model disagrees with observation, therefore model is wrong.

Obviously.

Aug 13, 2015
I suggest that there is no "obviously" about it - the calculations may indeed be wrong but I'm certain that this is far from obvious or those same calculations would have had the obvious error(s) corrected.


Model disagrees with observation, therefore model is wrong.

Obviously.


This is an important issue," says Stefan Ulmer, who led the research, "because it helps us to understand why we live in a universe that has practically no antimatter, despite the fact that the Big Bang must have led to the creation of both
Understand you say? It just makes your lack of understanding more apparent, Stefan... ;-)


I'm continuously amazed by the arrogance of amateur web pundits. When you guys start getting paid to do physics research and actually publish something worthy, only then start taking yourselves seriously. Only then will the rest of us do likewise.

Aug 13, 2015
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Aug 13, 2015
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Aug 13, 2015
Article states:- "..why we live in a universe that has practically no antimatter, despite the fact that the Big Bang must have led to the creation of both.."

There is another possibility given what we know of uncertainty & variance...

That there was an almost equal amount of matter/antimatter at the point of initiation which produced enough energy for the 'so called' big bang like event but, the variance in amount, although of many millions of a % difference show one type of matter is left over after all the annihilation conclude.

Although appears Vast in our matter based universe, what we may be seeing is just that small % left over, then as such, there is no problem re where anti-matter went etc.

The CMBR fine details & other clues founded at deepest level of QM which shares part of the paradigm may well cover this satisfactorily, in that case the variance although very small still results in a net amount of matter we observe.

I don't see a problem with that.

Aug 13, 2015
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Aug 13, 2015
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Aug 13, 2015
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Aug 13, 2015
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Aug 13, 2015
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Aug 13, 2015
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Aug 13, 2015
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Aug 13, 2015
Returners proselytising to a static deterministic opinion mode
Model disagrees with observation, therefore model is wrong. Obviously
Ugh !
Awful narrow simplification not worthy of intelligent cognition

In Science, especially Physics one learns early on issues of uncertainty in any & all measurements but, along with mathematics of limits & calculus & especially integration one can produce a valid model which carries through those measurement errors and through equivalent calculations as per the data pass through and generate valid "Error Bars"

One direct & practical application of the value of modelling & how it deals with obvious chaos & integration is the petrol spark ignition engine & its modelling performed by an engine computer

ie Chaotic process of combustion but, integration re heat/power is not. There is however an error bar/range which pops out & is measurable directly Eg Lambda/stoich, the feedback is fed back as Eg, same paradigm re AGW

Continued

Aug 13, 2015
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Aug 13, 2015
swordsman stated
"Antimatter" is a false term
Not when it comes to annihilation surely as both "resolve" to energy re E=mc^2

swordsman states
A black hole might be considered fit this term, but a black hole does contain matter, and a great deal of it
BH attracts matter/anti-M re gravitation & afaik mass of both protons <-> anti-protons is (so far) same

swordsman claims
Glitzy terminology might get attention, but at the sacrifice of reality
No. Although, from your earlier posts I see where your opinion originates

Consider Protons/anti-P fall into BH & annihalate but, after they've crossed the event horizon, all energy released eg gamma etc will be unable to escape thus be drawn to the massive center which may after-all be a sea of energy ie not as particles

Mass/energy in BH conserved whether anti-P or not, gravitation continues unabated

I don't accpet center of BH has zero size, likely n-planck relationship

BH gravitation confirmed re observation

Aug 13, 2015
Still using a quadro-polar unit of measure, i.e. mass, as a unit of measure of a mono-polar object! Why not start over with just + and - points within a 4D space. I would use c = lambda nu to define equal units, thus a unit-less hypothetical space. Didn't want to use "abstract" since all the measurements are real, from +/- infinity. So we can assemble, +1 and -1 into any form and number we wish. Just keep an eye upon the sea of the faster moving charges each object may be placed, it always finds a stable point without interference. Is charge elastic or transparent? We know how it moves, relatively, conceptually no limits, so ...

Maybe we should rethink anti-matter is not anti- at all! In fact, we haven't began to define charge; but do we have some cool tools!

Aug 13, 2015
You may discern from a 4D model, that reversing the charge of a single atom within empty space will produce the same gravitational field. Since gravitation is always attractive, regardless of the mass of the proton and the electron, neutron as a pair, leaves only the particle count without a proper description of the state of matter, i.e. mass is not a proper unit of measure. It's only the field we measure. Since all particles states superimpose to produce a summation of the potential field, gravity. But don't miss the simulation of a single particle's field as it moves by itself in empty space, i.e. pick your relative perspective carefully. E = MC^2 is nonsense created from quanta and deBroglie, m is no-where properly defined and has never been axiomatic.

If it is only charge, is charge transparent? The fields overlay and add in this vector space, so ... each point has a set of attributes. Define each element's possible state. then we try to define matter.

Aug 14, 2015
I suggest that there is no "obviously" about it - the calculations may indeed be wrong but I'm certain that this is far from obvious or those same calculations would have had the obvious error(s) corrected.


Model disagrees with observation, therefore model is wrong.Obviously.


Dark Matter Enthusiasts would disagree with you......but then again, how many of them have ever seen a Differential Equation they could solve?

Aug 14, 2015
Benni with very Best he could do
Dark Matter Enthusiasts would disagree with you......but then again, how many of them have ever seen a Differential Equation they could solve?
Why continued pre-occupation with DE's, they are taught as standard in most high school 'year 12' prior to university level.

You seem to be tangentially implying your maximum level of education is DE's, so is this taken as confirmation you have missed out on uni studies so therefore your implication of higher study in may other posts are false ?

Benni I've challenged you on a few occasions over the past months as have others & especially so re this DE re heat/climate

https://en.wikipe...transfer

In respect of your jibe re claiming unknown people cannot do what you imply you can, then why have you never been able to; address it, manipulate or even pursue some evaluation under appropriate conditions.

Eek a real DE - oh no !

Lol

Aug 14, 2015
I'm continuously amazed by the arrogance of amateur web pundits. When you guys start getting paid to do physics research and actually publish something worthy, only then start taking yourselves seriously. Only then will the rest of us do likewise
Whoa. First he needs to get sober and then he needs a decade or so of education and experience.

Getting sober is the hard part eh Lrrrkrrrr?

Aug 15, 2015
thus be drawn to the massive center which may after-all be a sea of energy ie not as particles

Particles that aren't indivisible (electron? quarks?) will be torn apart/decay long before they reach the center. Forces like the weak force (and the strong force) are limited to below the speed of light. So any kind of spatial imbalance (nucleons within a nucleus or even the quarks within nucleons) means that some will stop feeling the forces of their brethren that are further 'in' once the event horizon is crossed.
(Actually this means that such composite particles as protons, neutrons - and of course entire nuclei - will already disintegrate ever so slightly before they hit the event horizon whne the imbalance grows large enough)

Aug 16, 2015
thus be drawn to the massive center which may after-all be a sea of energy ie not as particles

Particles that aren't indivisible (electron? quarks?) will be torn apart/decay long before they reach the center. Forces like the weak force (and the strong force) are limited to below the speed of light. So any kind of spatial imbalance (nucleons within a nucleus or even the quarks within nucleons) means that some will stop feeling the forces of their brethren that are further 'in' once the event horizon is crossed.
(Actually this means that such composite particles as protons, neutrons - and of course entire nuclei - will already disintegrate ever so slightly before they hit the event horizon whne the imbalance grows large enough)

How do you know this? PhD does not know truth, for them its a search. Common sense not included. did anyone find anything other than charge? Anti-matter, huh? Nonsensical!

Aug 16, 2015
'Particles that aren't indivisible (electron? quarks?)...Did you intend a double negative here? 'aren't indivisible ' implies that they ARE divisible..electron & quarks divide into what? (other than gamma)

Aug 18, 2015
The really interesting part of this is the finding that matter and antimatter behave the same WRT gravity to within a few PPM.

Aug 18, 2015
'Particles that aren't indivisible (electron? quarks?)...Did you intend a double negative here?

Good catch...I was trying to write indivisible...but wanted to change to "not divisible"...and stuff got jumbled.

It is currently uncertain whether electrons or quarks can be split given sufficiently high energies. If they can't be split then they would (presumably) survive inside a black hole.

How do you know this?

Forces are mediated via force carriers (photons, gluons, W/Z bosons....possibly gravitons, but the latter has, as of yet, no experimental evidence to back it up). As such the force carriers are limited to the speed of light (or below). Put that together with the fact that at - or within - the event horizon nothing can move further away from the center of a black hole and you get the conclusion I have outlined above.

Aug 18, 2015
When particles move past the event horizon of a black hole, the relativistic effects that convert space into time are maximally contorted, such that the putative singularity at the center of the black hole becomes their future, not just their destination. What this means in real terms no one knows, but it is indicative of the weird physics that must obtain beyond the event horizon.

There might be unicorns in there, but if there are, we'll never know.

Personally my opinion is that all the mass a black hole "eats" is trapped in the region just outside the event horizon. The shell theorem means that this cannot be distinguished from it being inside the event horizon; the gravity effect will be the same. Nothing, in this view, ever passes the event horizon; it just keeps getting more and more infinitesimally closer to the event horizon.

contd

Aug 18, 2015
contd

This is dictated by the fact that as things come closer and closer to the event horizon, their apparent time grows slower and slower according to relativity.

Thus, my answer to "what's inside a black hole" is "nothing." All the mass the hole has, as we see it, is concentrated into the region just outside the event horizon, going slower and slower, and never quite crossing the event horizon because it can never get there due to time dilation.

I am surprised that no one ever notes this as a possibility in the literature.

If there is any material inside the hole, it is what was already inside the event horizon at the time the hole was formed; everything else the hole has "eaten" since that time is, as I say, concentrated just outside of the horizon.

That is, if relativity is correct in the ultraviolet limit.

contd

Aug 18, 2015
contd

For reference, the shell theorem states that if all the material supposedly inside the radius of a sphere were concentrated on that sphere's surface, outside the sphere no difference could be told between that situation and the situation where the material is evenly distributed within the sphere, nor the situation where all the material is concentrated at the center of the sphere. This theorem has been known since the seventeenth century, and was first proved by Sir Isaac Newton. https://en.wikipe..._theorem

Since it is a theorem, not a theory, it is capable of mathematical proof, and Newton provided that proof.

See conclusion #1 in the introduction of the Wikipedia article.

Aug 18, 2015
This is dictated by the fact that as things come closer and closer to the event horizon,

However the subjective time of someone approaching the event horizon does not change. So they definitely would cross over (if they could cross over whole, that is).
What an outside observer sees is just the last few seconds stretched out to infinity (well..not even that. As the number of photons emitted prior to crossover is finite. So there is a time by which the last photon - severly redshifted and at a much later date as it may be - is recieved)

The shell theorem comes about because all paths that cross the event horizon end up at the singularity. So however you are looking at the event horizon you are always looking in direction of the singularity. But the way I see it that in no way says that stuff stays at the event horizon (that is only an apparent effect...it would also go counter to all kinds of conservation laws, like conservation of momentum).

Aug 19, 2015
This is dictated by the fact that as things come closer and closer to the event horizon,
However the subjective time of someone approaching the event horizon does not change. So they definitely would cross over (if they could cross over whole, that is).
Hmmmm, seems to me (supposing we agree to ignore the tidal spaghettification problem as you have) that the last few seconds before encountering the EH would get stretched out from the rest of the universe's POV, eventually into billions of years. I don't see how anything can ever be observed (again, from the outside universe's POV) to actually cross the EH. It'll just seem to get closer and closer more and more slowly. Can you please explain why not?

it would also go counter to all kinds of conservation laws, like conservation of momentum
I'm not quite clear on how it would violate momentum conservation. Can you explain that more carefully, please?

contd

Aug 19, 2015
contd

I should be careful here to note that the shell theorem merely explains why we couldn't tell if this situation (all the mass that's supposedly past the event horizon is actually packed just outside it) were correct, or if the mass had actually passed the EH; the gravity effects would be essentially the same. It's time dilation as you approach the EH that is the actual cause of this (assuming of course that I'm right, and I can't see, given that time dilation, how I can be wrong).

Suppose, for the sake of argument, again ignoring spaghettification by tidal forces, we could send a probe in very close to the EH, and then have it come back. Wouldn't it come back to find out millions or billions of years had passed in the outside universe? My understanding is that at the actual EH, time dilation is infinite, from the POV of the rest of the universe. Is that not correct?

Aug 19, 2015
I looked this up on Wikipedia here: https://en.wikipe...dilation

Note that I rearranged the equation to give coordinate time instead of proper time as the output.

It says the ratio of coordinate time (far away from the black hole) to proper time (falling into the black hole) is:

t[c] = t[p] / ⎷(1 - r[s]/r)
Where,
t[c] is coordinate time
t[p] is proper time
r[s] is the Swartzchild radius (i.e. radius of the EH)
r is the distance of the close in observer from the center of the BH

Now, if r = r[s], then r[s]/r = 1, 1 - 1 = 0, and ⎷0 = 0. Thus, an observer far from the BH sees the proper time of the observer at the EH as stopped; any amount of proper time is an infinite amount of coordinate time. I was pretty sure I was right about that. I think I'm right here. I might not be for a Kerr BH (rotating) and I'd be interested to know by how much I'd be off, say at the equator of the BH.

Aug 19, 2015
I don't see how anything can ever be observed (again, from the outside universe's POV) to actually cross the EH. It'll just seem to get closer and closer more and more slowly. Can you please explain why not?

I agree with the observation part. We see the not-quite-crossing-over forever...in theory. In practice we see the object fading so far into the low end of the electromagnetic spectrum that it becomes undetectable by even theoretical receivers due to th massive redshift almost instantly.

Also remember that 'seeing' is the act of receiving at least one photon. The object doesn't suddenly start emitting more photons just because it gets close to the event horizon.

I'm not quite clear on how it would violate momentum conservation

If the matter were truly stuck at the event horizon then all motion would be reduced to a tangential trajectory. Any kind of radial momentum it had would somehow go 'poof'...and I'm not sure by which mechanism that would be possible.

Aug 19, 2015
I should be careful here to note that the shell theorem merely explains why we couldn't tell if this situation (all the mass that's supposedly past the event horizon is actually packed just outside it) were correct, or if the mass had actually passed the EH; the gravity effects would be essentially the same.

I agree with this. My point is:
From the outside we don't see stuff pass the event horizon.
From the outside we cannot tell whether stuff is on the event horizon or inside by any kind of measurement.
However: Stuff does pass the event horizon nevertheless.

Wouldn't it come back to find out millions or billions of years had passed in the outside universe?

Still that does not prevent the probe itself from crossing over (if it chose to do so instead of coming back). It is accelerated inwards on its trip and would cross over in finite time in its own reference system (i.e. send out a finite number of photons before it crossed over).

Aug 19, 2015
There's also the issue that the event horizon isn't static. Anything being added to the black hole will increase the radius of the vent horizon. If nothing ever could reach the event horizon then a black hole couldn't grow.
So we could get to the paradoxical situation that stuff resides on the horizon but the horizon grows...which means having that stuff move further away from the singularity. which - I think - isn't allowed.

Aug 19, 2015
Anti-matter is only theory, not fact. Quarks are theory, not fact. GR is theory, not fact. Given only + & -, call it charge, we know the calculations, we know mass does not define charge, we know we do not know what charge really is. So its all in your head! Best to start over, define gravity as a field, true. Why not a superposition of the charges? Mass not included! Hindsight! Think! Divide all mass by the sum of the proton and electron mass, i.e. number of particle pairs, the dynamics?? Neutrons are a containment of a + & - charge. Nothing else. Simple, simulate only the +1 and -1 withing a 4D space using c=lambda nu -> a unit for all dimensions with the globe from each charge defined, etc. Do something other than create things that pop into your head! The above is an exercise in "religion", i.e. a belief, not logic or science.

Aug 19, 2015
A containment, +&-, as a neutron will be stable and zero when alone in space. Any field will separate; therefore, a containment is required, such as a nucleus. Simulate it. For anti-matter, try a proton as a rota-tor about an electron, simply define the necessary relative velocity to place the + in orbit. Send this atom into a field of normal atoms for our world or a cloud chamber. "Oh I see said the blind man as he picked up his hammer and saw entire galaxies of matter with different rota-tors collide and throw off excessive gamma particles from extremely fast reactions!

Aug 19, 2015
I don't see how anything can ever be observed... to actually cross the EH. It'll just seem to get closer and closer more and more slowly.
I agree with the observation part.
I'm more interested in the gravitational part.

We see the not-quite-crossing-over forever...in theory. In practice we see the object fading so far into the low end of the electromagnetic spectrum that it becomes undetectable by even theoretical receivers due to th massive redshift almost instantly.
But it's still, from our POV, just outside the EH. And I can't see, if the equations I posted or correct, how it can ever actually pass it in our universe.

Also remember that 'seeing' is the act of receiving at least one photon. The object doesn't suddenly start emitting more photons just because it gets close to the event horizon.
Sure but the question is whether the mass ever actually crosses the EH, and the answer appears (from those equations) to be "no."

contd

Aug 19, 2015
contd

I'm not quite clear on how it would violate momentum conservation
If the matter were truly stuck at the event horizon then all motion would be reduced to a tangential trajectory. Why? Just because the BH and EH are rotating doesn't impart rotation to infalling matter.

Aug 19, 2015
I should be careful here to note that the shell theorem merely explains why we couldn't tell if this situation... were correct, or if the mass had actually passed the EH; the gravity effects would be essentially the same.
I agree with this. My point is: ...Stuff does pass the event horizon nevertheless.
In its own frame, but from the POV of the rest of the universe nothing ever has; it hasn't been long enough (and if those equations are correct, it never will be).

Wouldn't it come back to find out millions or billions of years had passed in the outside universe?
Still that does not prevent the probe itself from crossing over (if it chose to do so instead of coming back).
But it will never happen according to our POV.

contd

Aug 19, 2015
contd

It is accelerated inwards on its trip and would cross over in finite time in its own reference system (i.e. send out a finite number of photons before it crossed over).
I agree with this, but point out that (again, if the equations from the Wikipedia article are correct, and I believe they are, with, again, the proviso that it may not be so for a real (i.e. Kerr) BH), nothing ever actually "falls in" past the EH according to coordinate time (that is, our time as observers far from the BH).

I'm really interested in whether the exposure of the ergosphere has any impact on this situation.

Aug 19, 2015
There's also the issue that the event horizon isn't static. Anything being added to the black hole will increase the radius of the vent horizon. If nothing ever could reach the event horizon then a black hole couldn't grow.
So we could get to the paradoxical situation that stuff resides on the horizon but the horizon grows...which means having that stuff move further away from the singularity. which - I think - isn't allowed.
Now this is a fairly strong argument, but it's controverted by the shell theorem. I'll point out that we can't detect the EH for a BH; we can only observe its apparent mass.

OTOH, perhaps the mechanism is that the EH "grows past" the matter, at the last moment due to the addition of mass *even though it starts out past the EH*. After all, the location of the EH is determined by X mass within R radius, and you can't keep adding mass to a shell just outside the radius without increasing the radius. I suspect this is the answer to my conundrum.

Aug 20, 2015
In its own frame, but from the POV of the rest of the universe nothing ever has;

But we don't observe all the events that happen in the frame of the thing passing the event horizon. We only observe the part until it reaches the event horizon - and that part stretched out over, for us, infinity. The rest of the journey is cut off from our perception (but not from what actually happens). The arbiter of what is real is not a far off observer but the object.

If the matter were truly stuck at the event horizon then all motion would be reduced to a tangential trajectory. Why?

All paths at the EV are almost completely radial.
If the stuff truly did not cross the EV then the radial component relative to the EV must be reduced to zero (or as close as makes no difference). This would mean all radial momentum would have to become zero and only tangential momentoum would (could) remain. I can't get that to work with conservation of momentum.

Aug 20, 2015
If particles and waves are the same; then each charge would be transparent. If so, a black hole would disappear from reality, i.e. infinite density, therefore no field. So maybe we're wrong!

So infinite density is fantasy! It makes no sense!

Aug 20, 2015
The arbiter of what is real is not a far off observer but the object.
That sounds more like philosophy than physics. It also seems like a footless dispute to me; we could argue all night about which twin is "right" in the twin paradox. Fact of the matter is, they're both right in their own frames. Same here.

If the matter were truly stuck at the event horizon then all motion would be reduced to a tangential trajectory. Why?
All paths at the EV are almost completely radial.
No, that's a constraint on all stable orbits. Better double-check your references on that one.

Aug 21, 2015
The arbiter of what is real is not a far off observer but the object.
That sounds more like philosophy than physics. It also seems like a footless dispute to me; we could argue all night about which twin is "right" in the twin paradox. Fact of the matter is, they're both right in their own frames. Same here.

If the matter were truly stuck at the event horizon then all motion would be reduced to a tangential trajectory. Why?
All paths at the EV are almost completely radial.
No, that's a constraint on all stable orbits. Better double-check your references on that one.

The way I see it, everyone seems to know all this yang makes no sense!

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