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Spinning Black Hole's Edge Rotates At Nearly the Speed of Light
astroengine writes "Astronomers have directly measured the spin of a black hole for the first time by detecting the mind-bending relativistic effects that warp space-time at the very edge of its event horizon. By monitoring X-ray emissions from iron ions (iron atoms with some electrons missing) trapped in the black hole's accretion disk, the rapidly-rotating inner edge of the disk of hot material has provided direct information about how fast the black hole is spinning. Astronomers used NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) — that was launched into Earth orbit in June 2012 — and the European observatory XMM-Newton measured X-ray radiation as a tool to directly infer the spin of NGC 1365's black hole. 'What excites me is the fact that we are able to do this for the very massive black holes at the centers of galaxies but we can also make the same measurement for black holes in our galaxy ... black holes that resulted from the explosion of a star ... The fact we can extend this from billions of solar masses to 10 solar masses is pretty cool,' Fiona Harrison, professor of physics and astronomy at the California Institute of Technology, Pasadena, Calif., and principal investigator of the NuSTAR mission, told Discovery News."
i love how this summary explains what an ion is, but assumes i know the definitions of black hole, x-ray, and solar mass. great writing, folks!
Have they shown that the black hole is rotating near c, or just that the accretion disk is rotating near c at the event horizon? The accretion disk and the black hole are not necessarily spinning in sync. If they mean the accretion disk, then, like DUH: if it wasn't rotating near c, it would fall straight in and there wouldn't be a disk.
My thought has always been that black holes are black because the particles they are made from move faster than the speed of light, therefore don't give off light radiation...same with the theory of Dark Matter/Energy....they all contain particles that have aspects that move FTL, and when crossing the FTL barrier means not that it doesn't have mass, that it abnormal mass... But what do I know, I'm not a scientist, or really all that smart. Meh...one of those theories I came up with decades ago after watching too much discovery channel.
Could the near light speed rotation of the SMB be equivalent in some way to having extra mass at the core of the galaxy? In other words, does this change how much dark matter there must be?
I come here for the love
The speed of light is influenced by gravity?
The speed of light in a vacuum is a constant. It never changes.
Time, on the other hand, is different almost everywhere. My hypothesis is that the the speed of light and time have switched places in someones private universe.
But does it run Linux?
Gravity certainly bends light. But as far as slowing it down, I always thought was a constant represented by the letter "c".
I had a Honda Civic that could go the speed of light. It sucked because nothing ever showed up in the rear view mirror.
Let's make like a bird... and get the flock outta here.
http://helios.gsfc.nasa.gov/qa_sp_gr.html
" Yes, light is affected by gravity, but not in its speed. General Relativity (our best guess as to how the Universe works) gives two effects of gravity on light. It can bend light (which includes effects such as gravitational lensing), and it can change the energy of light. But it changes the energy by shifting the frequency of the light (gravitational redshift) not by changing light speed. Gravity bends light by warping space so that what the light beam sees as "straight" is not straight to an outside observer. The speed of light is still constant."
Dr. Eric Christian
Speed is distance over time. If time slows down, then light will appear to slow down to an observer in another frame of reference. However, speed is unaffected, it takes the same amount of time to cover a set distance within the same frame of reference - it just appears to be slower to an outside observer.
In my limited understanding of these things, (mostly from articles meant for mass consumption, not scholarly journal papers), I imagine a black hole to be so massive not even light can escape its gravitational pull. Which technically means the escape velocity is the speed of light. So anything at the event horizon should be at the speed of light. This is of course, a naive view. The escape velocity is based on Newtonian, not Relativistic, physics.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
So many people (a number of whom who should know better) get this totally wrong because you always here that a black hole has "such powerful gravity that not even light can escape!!!111!!!"
This is another failing of Science Channel styled science shows*. They neglect to tell you that light doesn't escape because the gravity well created by a black hole warps space, not because photons are pulled on by gravity. It may sound like I'm splitting hairs since the overall end result is the same but a lot of people mistake it as meaning that light is sucked in to the black hole because particles with mass are also sucked in. This also doubtlessly leaves people scratching their head over the misconception that maybe the gravity is forceful enough to actually attact the light.
* Yeah, I'm the guy who complained about definitions being used too often in another thread.
it is just that our warp tech is not yet caught up with your honda civic.
I think you should have somebody take a look at your shift key.
Let's make like a bird... and get the flock outta here.
c is a constant represents the theoretical maximum speed of light. The problem is that the speed of light is not constant. Light slows down in a medium.
Learn to love Alaska
Moving close to the speed of light relative to what?
As with most deep space observatiosn and calculations.... They are all built from a house of cards. Too many assumptions and too many variables. We may soon actually find out that the edge of a blackhole is not moving at all instead of at the speed of light and then a few tweaks to the first theory or a few assumption and bam, yep, now we think its not moving at all.
In some mediums, light moves faster than it does through a vacuum. c is the speed of light in a vacuum, not the "theoretical maximum speed of light"
It may sound like I'm splitting hairs since the overall end result is the same but a lot of people mistake it as meaning that light is sucked in to the black hole because particles with mass are also sucked in. This also doubtlessly leaves people scratching their head over the misconception that maybe the gravity is forceful enough to actually attact the light.
Light has momentum (which "require" mass in more classical thinking). Light is "moved" by gravity (which indicates mass). If mass distorts space so that it makes light and particles behave the same, then why is it a misconception to think of light as a particle? It's both a particle and a wave, thus *is* a particle.
Learn to love Alaska
If it's anything like my last Honda Civic, that's because the mirror fell off and is sitting under the passenger seat.
Learn to love Alaska
Doesn't the light have a constant speed for all observers but it's frequency is shifted for an observer in a different frame of reference ?
You seem to regard science as some kind of dodge... or hustle.
Wrong, so very wrong.
Not a physicist of any kind, but I had thought that information could not cross the event horizon? If that is true, then how can we construe that the speed of matter near the event horizon indicate the speed of rotation of the black hole? Wouldn't it only indicate the speed of that particular matter? Educate me if I'm wrong!
Most of the Science Channel-style science shows I've seen that cover the issue not only cover that light doesn't escape the gravity well because the gravity of the black hole warps space, but also covered that that's how all gravity works, not just a special variation related to "black holes" as the source or "light" as the affected entity. (As do the more technical, less Science-Channel-ish, works that I've seen addressing the same subject matter.)
The "sucked in" analogy is exactly as accurate (or inaccurate) applied to light as it is to "particles with mass".
Which actually is correct (except for "here" instead of "hear" :-)). What's wrong is the imagination that this is because the light is slowed down when going outwards (actually in some sense the light is slowed down, because the time as seen from outside is slowed down; but that's independent of the direction, and of course locally it is still going with c). The real reason is that the spacetime (not space, spacetime) is curved in a way that there's no way out when going at light speed or below. That is, the outward-going light is still going with light speed, but will not get out, but eventually reach the singularity. Yes, that seems paradox, since the singularity is "in the middle" (which isn't entirely accurate either; for a non-rotating black hole it is actually in the future), but that's because we are not very good in imagining curved four-dimensional spacetimes.
The Tao of math: The numbers you can count are not the real numbers.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
No, time is the same everywhere, too. Only the length of timelike paths depends on how you move. But ultimately it is not too different from the fact that the length of spacelike paths depends on the way you take. Except that for spacelike paths, the direct path is the shortest, while for timelike paths, the direct path is the longest.
The Tao of math: The numbers you can count are not the real numbers.
TFA mentions a fact that I'd read about before, that the black hole's rate of rotation increases as it collapses due to the conservation of momentum. But since no matter can actually mover faster than the speed of light, is the collapse limited by this maximum rotation rate? Would the black hole cease collapsing when the rotation rate neared the speed of light?
-----
Sorry, I'm only a 1336 h4x0r.
Light (photons) have no mass. Mass will deform the space-time fabric around the object creating a well of sorts. This "space-time well" can be very "deep" for a black hole because is so massive. So deep it can trap light.
The article talks about the implicit spin of a black hole. It is implicit because it can't be measure directly. It is based on the amount of photons (i.e. X-rays) it emits and the difference of those emissions when the black hole is not rotating, is rotating against the debris spiraling into it (accretion disk), or is rotating with the debris spiraling into it. There seems to be correlation between those emissions and the the rate and direction of rotation relative to the accretion disk.
In some mediums, light moves faster than it does through a vacuum.
No, it doesn't. Not only does such a material not exist, it is proven beyond any reasonable doubt to be impossible.
c is the speed of light in a vacuumm
Hey! You got something right!
not the "theoretical maximum speed of light"
And right back to wrong. Nothing can travel through space (empty or otherwise) at faster than c, that is the central concept of relativity.
And you're always adjusting the in-dash clock.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
FTA:
Imagine a sphere more than 2 million miles across - eight times the distance from Earth to the Moon - spinning so fast that its surface is traveling at nearly the speed of light. Such an object exists: the supermassive black hole at the center of the spiral galaxy NGC 1365.
If it were a rigid body,
Rotation Rate omega = Tangential Speed nu / 2pi * Radius r = 186 280 mi/s / 6.2832 * 2e6 mi = 0.014824 cyc/sec = 0.88942 cyc/min
Roughly one revolution per minute. Not an amazing rotation rate for objects of scales we're used to, but for something 2 million miles across it's pretty impressive.
Now, an event horizon is anything but a rigid body, so I could be waaaaay oversimplifying. But the article says "imagine a sphere..."
Anyone care to extend the math to apply to something other than the theoretical physicist's favorite imaginary object?
I can see the fnords!
If I were to build a disc with its inner ring located near (but not inside) the event horizon of this black hole, and an outer ring located a few million kilometers away, at what speed would the outer section of the disc spin? What would happen along that outer edge?
!#@%*)anks for hanging up the phone, dear.
Time and space are influenced by gravity, and speed depends on both.
Three dimensions.are mind boggling enough, once you are inside the BH, light is bent such that all directions are pointing towards the "middle", it's sort of like the 3D equivalent of asking which way is north when you are at the south pole.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Probably the CNN question would be if supermassive black holes are caused by global warming or maybe that they started to rotate so fast due to global warming. Anyway, small things after they ask if the bing bang was caused by global warming.
In some mediums, light moves faster than it does through a vacuum.
No, it doesn't. Not only does such a material not exist, it is proven beyond any reasonable doubt to be impossible.
That depends on what exactly you mean with the "speed in the medium".
You certainly can have a phase velocity larger than c, and AFAIK you also can have a group velocity larger than c. What you cannot have is a signal velocity larger than c.
The Tao of math: The numbers you can count are not the real numbers.
Actually it is already a misconception that particles are sucked in. Particles can fall in, but they also can orbit the black hole (as long as nothing else is in the way), just as they can orbit earth. If they get too close they no longer can orbit the black hole for the simple reason that they would need to go faster than light to do so.
The Tao of math: The numbers you can count are not the real numbers.
Not to repeat what other replies are saying, but I think maybe you mean "In some mediums, charged particles can be found travelling faster than the speed of light in that medium". Are you thinking of cherenkov radiation?
For a non-rotating black hole in Schwarzschild coordinates, the radial vector inside the horizon gets timelike, that is, the singularity is not really "in the middle" but "in the future". This quite intuitively explains why you cannot go "outward": The "outward" direction is actually the past direction.
Now, Schwarzschild coordinates are not the full story, but neither are Eddington-Finkelstein coordinates (which obviously are what you had in mind). The complete structure of the Schwarzschild solution can only be seen in Kruskal coordinates, where you on one hand quite literally see that the singularity is in the future (for any world line starting outside the black hole and entering it), but you would still be able to evade it if you could travel faster than light (while in Schwarzschild coordinates it looks as if you'd have to travel backwards in time).
Anyway, light is not "bent towards the middle", that's only the result of non-ideal coordinates where the singularity appears spacelike while it is actually timelike.
For rotating black holes, things are more complicated (there are two horizons, the singularity is spacelike, but not a point, and inside the black hole there occur closed timelike curves).
The Tao of math: The numbers you can count are not the real numbers.
Well, at the big bang, it was extremely hot everywhere in the universe. So how could that have happened except by global warming? :-)
The Tao of math: The numbers you can count are not the real numbers.
Are they sure they're not seeing the light-speed reflections of another source? If I shine a laser at the moon and wiggle it, I can make the dot "move" really fast.
Please explain time, please explain whether it is continuous or not. And if you have time explain further relative to this case :)
thanks
Don't you just love armchair physicists!!!
My karma is bad. Don't get too close!!!
Light has momentum (which "require" mass in more classical thinking). Light is "moved" by gravity (which indicates mass)
Also light has energy which is mass in Relativistic thinking, and is moved by (and moves other things by) gravity which is due to it's energy (same as mass).
This is confusing because people think of "mass" as the things photons don't have and matter does (which is true if we mean intrinsic mass), but also think of "mass" as the thing which effects/is affected by gravity and makes objects resist acceleration, when that's actually the relativistic mass (= energy).
It's both a particle and a wave, thus *is* a particle.
A photon is a quantum mechanical particle, which is a thingie which behaves kinda like a classical particle and kinda like a classical wave but not exactly like either.
However the key thing about quantum mechanics is that stuff is quantized... like particles are. So we call them particles. There is no misconception in doing so.
The enemies of Democracy are
Ironically I iron my clothes with iron iron ions
In some mediums, light moves faster than it does through a vacuum.
No, it doesn't. Not only does such a material not exist, it is proven beyond any reasonable doubt to be impossible.
Your statement would seem to be contradicted by this theory on faster-than-c speeds between 2 Casimir plates.
It does not. It only looks that way due to the reactions with electrons.
You must also think that light travels in a straight line?
GR assumes time is continuous. There have been some theories that space and time may be quantized, but none so far have any great evidence pointing their way, and some have evidence pointing away from them when they were able to make predictions that are measurable. Further research on the topic is on going. Even if it turns out space-time is not continuous, it would probably only be relevant to small black holes, which is where the idea got a big jump when trying to deal with information theory and small black holes.
c is a constant represents the theoretical maximum speed of light. The problem is that the speed of light is not constant. Light slows down in a medium.
meh, you are almost right.
C is a constant that represents the maximum speed of light *in a vacuum*.
That "in a vacuum" piece is quite important. The medium itself has no effect on the constant c ( constant is a constant), but each medium has its own value of light propagation speed which is *always* less than c.
Think of 'c' as the speed of reality.
I take your reasonable doubt and counter it with un-reasonable doubt.
Thats more than enough for many people, sadly.
If they get too close they no longer can orbit the black hole for the simple reason that they would need to go faster than light to do so.
So you are saying that the singularity curves time-space so much that you'd have to travel infinitely far to be able to leave a black hole, and speed is irrelevant. The light orbits the singularity inside the event horizon, and will never leave, nor contact the singularity itself. Or something like that.
Learn to love Alaska
You must also think that light travels in a straight line?
Light thinks it does, just like standing on a trampoline and rolling a ball, the ball travels in a straight line, in a curve around you. Gravity curves space such that light travels in a straight line, and the universe curves around it.
Learn to love Alaska
C is a constant that represents the maximum speed of light *in a vacuum*. That "in a vacuum" piece is quite important.
If there is no material in which light travels faster than C, then your clarification is irrelevant.
Learn to love Alaska
If the matter on the outer edge of the disc is spinning near the speed of light, and if that matter is gravitationally bound to the rest of the disc and the black hole itself, then eventually the outer edge of the disc should act as a brake on the entire black hole's spin rate (because it can't exceed c). If it were to experience additional imparted momentum, what would happen to spacetime at the edge? I'm curious what the frame-dragging implications of this are.
Is this simply a matter of the amount of energy needed to approach c is so large that even galactic-sized energies aren't significant?
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Could we no use the spinning black hole at light speed to beam unlimited energy to sol? Do this before this gets erased. My time on this planet is limite
The propagation of the electric and magnetic fields slows down in bulk when going through media. It does involve the electrons the vast majority of the case, but that doesn't change that the light is actually slowing down. It is not like that light is simply bouncing between atoms except for when you get to light with really short wavelengths.
Light in a vacuum does travel in a "straight line" although the definition of straight line usually becomes a geodesic when dealing with curved surfaces.
There is a distinction to be made between sucking and pulling (as far as physics...). But for others trying to use that to make some point about gravity are missing the actual point. It is a leaping off point to describe the behavior of pressure and air, to give examples of how atmospheric pressure does useful things for us. That is where the distinction is pedagogically useful, and not so much insightful into gravity.
The light orbits the singularity inside the event horizon
The only place the light can fully orbit the black hole is exactly at the event horizon, and it is an unstable orbit that would be destroyed by any other near by matter. Once inside the event horizon, light cones all point inward to the point that even at the speed of light, you could not remain at a constant radius from the center.
Objects in Mirror are closer than they appear.
The only place the light can fully orbit the black hole is exactly at the event horizon, and it is an unstable orbit that would be destroyed by any other near by matter. Once inside the event horizon, light cones all point inward to the point that even at the speed of light, you could not remain at a constant radius from the center.
So light slows down inside singularity? Because at the speed of light, it would be in a stable orbit at the event horizon, right?
And an unstable orbit is an orbit, still a "full" orbit.
Learn to love Alaska
Objects in Mirror are bluer than they appear.
FTFY
USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
There is no inside the singularity, it is a 0 dimensional point or a 1 D ring in GR (which may be wrong about that and superseded by a new theory in the future...). And regardless, the speed of light is constant, both inside and outside the event horizon. If you look at an expression showing what speed is needed for an orbit, you get something below the speed of light outside the black hole (as long as it is in the same direction as a spinning black hole, or either direction for non-spinning black hole), the speed of light right at the event horizon, and above the speed of light inside the black hole.
And by fully orbit, I mean go in a repeating pattern around the black hole. You could in principle call the parabolic trajectory of an object dropped to the ground an orbit even though it intersects with the Earth, and in the same sense any trajectory within the event horizon will intersect with the singularity. The trajectory of any object or light within the event horizon will never return to the same radius as it previously was. The trajectory of light outside the black hole would only pass any given radius at most twice, absent a third compact object that could spin it back around. That would be analogous to a hyperbolic classical orbit, it goes in, either crosses the event horizon never to leave, or comes out to never come back to the black hole.
The only place that light can orbit, as in visit the same radial distance more than twice, would be exactly at the event horizon. But it is impossible outside of some deficit in GR to get light into such and orbit, and any light in such an orbit would leave the orbit in the presence of any other matter additional matter outside the black hole. That is why it is unstable, because the smallest push will change the trajectory into something that will never come back.
"speed of light" is meaningless -- because it's not a constant. Might as well talk about the "speed of a honda civic".
I thought "the speed of a honda civic" was "fast and furious"... :)
Excuse me, wtf r u doin?
So light slows down inside singularity? Because at the speed of light, it would be in a stable orbit at the event horizon, right?
Yes and no. Light doesn't actually slow down. Time does. If a photon, at 300.000 km/s, gets close to the event horizon time slows down, so while it may still move 300.000 km in a second, that second takes longer and longer to pass. At the event horizon it takes an infinite amount of time.
Therefore if you are looking at it from the outside (and if the light you are using to look with doesn't have these pesky relativistic effects we are talking about) you'd think the photon has stopped.
[/armchair physics without much official education in the direction]
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
So when Milamber (in one of the books of Feist) moves the Lifestone a bit into the future to make it undetectable (you're always a bit late. You just missed it) he risked creating a black hole?
It sucked because nothing ever showed up in the rear view mirror.
It sucked because nothing showed up, or nothing showed up because it sucked?
Was your Civic black?
I was blinded by the black hole. No wonder I can't see it. All I see is all the starry affects circuling the galaxy around my head. Maybe, I need new gravitional lensed bifocal glasses due to my age.
"c is the speed of light in a vacuum"
But is it different depending on what sort of vacuum it is in?
EG would it be faster in A Dyson than in a Dirt Devil?
What's funny about this is if it isn't a constant, then why's it widely considered a limit?
When talking to the astrophysicists here, questioning their belief that the speed of light is unbreakable often gets the same reaction as questioning that the Bible happened to a fundamentalist Christian.
Science and religion really are two sides of the same coin.
Ironic captcha: tenant
Someone's been watching a bit too much Friendship Is Magic...
Spinning at "nearly the speed of light" is o.k.
Note: Anything faster will certainly not be approved.
Signed,
A. Einstein
Chief relativity supervisor
Umm, there have been several tested and failed models of variations in the speed of light to account for various cosmological scale effects. Additionally, at the small scale, chances in the speed of light alone would have messed up spectroscopic data that we have a plethora of now showing it doesn't.
If time slows to zero at the event horizon, then no matter could ever enter a black hole, right?
Learn to love Alaska
The problem is that uneducated people hear terms and take them in the non-scientific meaning, which often conflicts with reality. Science is like all tech fields. Nobody outside the field knows or cares about the terminology. 10 Gbps fiber is "baseband" and 128kbps DSL is "broadband" from the original definitions. But idiots misused the terms so much that the field gave up and neither term has any meaning anymore beyond "broadband" means "feels fast" and "baseband" means the floorboard that holds your carpet in place, or whatever "regular" people think of when they hear it.
The current scientific models seem agree that nothing can be accelerated from below the speed of light to above it, nor decelerated from above the speed of light to below it. There is nothing that indicates that nothing may travel faster than the speed of light, just corollaries that indicate that if anything is, we'd never be able to detect it. That you don't understand that (or are lying about what you believe) doesn't change reality, or what it's widely considered to be.
Learn to love Alaska
From the frame of reference of a distant observer, it appears no matter crosses the black hole. Instead, the matter gets closer and closer, but more and more red shifted, so it will still essentially disappear from view as all emissions are red shifted way into the radio region and emitted energy drops.
This comes about because essentially all observation from a distance needs to be carried by a signal that is at the speed of light or slower. When climbing out of the gravitational well removes a lot of energy from the photons, so they get red-shifted. And for more difficult to explain reasons, the speed of light is still the same, instead the meaning of distance gets messed up from such a point of view, so it is as if the signals are having to travel from very far, but still at the speed of light.
From other frames of references, things will cross the event horizon with no change, and particularly from the view of something falling into the black hole, the center is reached in a short, finite time.
The next question that brings up is, "What is the minimum energy of a photon?"
Learn to love Alaska
I don't know the book (I hope I don't have to hand in my geek card because of this :-)), but if the Lifestone is a bit in the future, shouldn't you be a bit too early? If I arrive at the place where an event shall happen, and the event is ion the future, I'm too early. If I'm too late, the event is already in the past.
Anyway, in the Schwarzschild solution, the singularity being in the future means you will get to it, because you simply cannot avoid going to the future.
The Tao of math: The numbers you can count are not the real numbers.
Well, in General Relativity time is continuous, and it is a dimension of spacetime. Spacetime is four-dimensional, with three space dimensions and one time dimension. Actually the time dimension only differs from the space dimensions by the sign in the metric (which basically means that as soon as time is involved, things are often reversed to what we are used in space, but the important part is that it makes it impossible to rotate the time dimension to a space dimension or vice versa; the metric is basically an onject which tells us how to measurte distances and angles). Also, while there are three space dimensions, there's only one time dimension (this makes it impossible to just turn around in time, as we can do in space). Note that this doesn't mean there's only one time direction; you can rotate the time axis in spacetime. That's known as boost; it's exactly what you do if you accelerate. Note that this is even true if you use a Newtonian spacetime, as one can easily convince oneself by simply drawing the world lines (i.e. the line describing at which place an object is at each point in time; to draw it, you certainly have to remove at least one spacial dimension). What's new in Special Relativity (which basically is a special case of General Relativity, namely the case of flat spacetime) is that also the space axis is turned on a boost, and in a way that the speed of light is the same in both systems. The time which elapses for you between two events is just the length of the world line (measured with the space time metric, with the different signs for space and time coordinates). Due to the different sign, the direct way is the one which takes the most time (unlike in space, where a detour makes the way longer). That's basically because if you detour in space, the change in the orthogonal direction adds to the distance, while for time, it gets subtracted (actually it's in the square of the distance where this addition/subtraction occurs, but the qualitative effect is the same: Moving in other dimensions at the same time adds to a length of a spacial path, but subtracts from the elapsed time, which is the length of the world line). This difference is generally known as twin paradox (the travelling twin makes the detour, and therefore he needs less time, and thus is younger than the waiting twin when he returns).
Now General Relativity adds to the mix that the spacetime is curved (and the curvature depends on the energy and momentum of the matter inside). That works in principle the same way as for example the curvature or earth's surface. For example, imagine two people meet somewhere at the equator, and one goes 5000 km west, and then 5000 km north, while the other first goes 5000 km north, and then 3535.5 km west. Then they get (approximately) to the same place, although the second one has gone a shorter distance. Quite similarly, someone going closer to the black hole and then remaining there will need less time than someone first waiting far away from the black hole and only then going close to it to meet the other one.
Note that the analogy goes even further: After going first north and turning west, to keep going west you have to constantly turn right (i.e. to accelerate in the direction of the pole). If you just went straight on, you'd start moving southwards, as if the pole would push you away. The acceleration causes you to keep at fixed distance from the pole. Similarly, the observer going close to the black hole (assuming he does not orbit it) has to accelerate away from it to not fall in; again this is the effect of curvature (of spacetime in this case). However spacetime around a black hole is curved in a way to make unaccelerated motion go towards it instead of away from it, thus the acceleration has to go away from it (orbiting is another way to keep from falling in; this option is not available in the earth surface analogy).
The Tao of math: The numbers you can count are not the real numbers.
In principle you could probably have a photon with a wavelength comparable to that of the observable universe, which would give an energy of almost 10^-52 J and associated with a temperature of 10^-29 K. Constructing an antenna or object that efficiently couples at that wavelength and sticks around long enough for attohertz frequencies might be another issue, and there is probably a lot of junk in the way further hindering that, even assuming there is not some unknown effect over such large distance scales that would block it.
For stuff falling into a stellar sized black hole though, it would quickly red shift out of view. Within one second, visible light would be redshifted to frequencies on the order a few Hz, which would have a wavelength larger than the black hole. After about an hour or so you would reach wavelengths on the size of the universe, and after about a day even high energy gamma rays would be redshifted to such an extreme value. (For a large black hole, like the one at the center of the galaxy, multiply these time scales by 10 million).
I would have to think for a while about the implications are of releasing a photon with that large of a wavelength is. Although I don't know how much it would matter, as it may very well just be easily absorbed by any intermediate matter, and if not, would be too weak to detect anyways. You could have something as outputting equivalent to the total luminosity of the milky way galaxy, and it would come out weaker than a light bulb at the same point that the 180 billion light year photons are coming out.
There might be a misconception about particles. The idea that material can be broken down to indivisible particles dates back to Aristotle. In the 20th century we proved that, well, actually, "atoms" aren't indivisible at all; there are electrons. The Plum Pudding model gave way to the Bohr model, which postulated that actually these atomic "particles" are mostly empty space and the electrons orbit the positive core in an eliptical pattern. But really that's it, the protons and electrons and neutrons are the elementary particles.
Oops, looks like there are smaller particles. And it looks like those smaller particles are made up of even smaller particles, and so on.
It wouldn't surprise me in the least if, as it turns out, everything we think is a "particle" is just a whirlpool in an all-expansive medium. This would make our current model of physics completely wrong, and it wouldn't be the first time in history that this were the case.
It is not like they haven't and are not continuing to test and look for structure of current fundamental particles. There have even been proposals for possible component parts, but they don't quantitatively hold up. The electron has been confirmed to be structureless down to a scale of at least 10^-22 m. The electron does interact with a soup of virtual particles, but the impact of that on electrons has been known for some time and the base theory, quantum electrodynamics, has been incredibly accurate quantitatively. The equivalent for exploring proton and neutron structure and interaction of quarks, quantum chromodynamics, is much more mathematically and computationally challenging, and the upper bound on their size or substructure size lags behind a couple orders of magnitude from the electron.
For comparison, the size difference between the size of an atom and that of a proton is about four orders of magnitude. Any structure to quarks would have to be at least another four or five orders of magnitude smaller to have not been seen by previous efforts, and another four orders of magnitude smaller for structure of an electron.
The enemies of Democracy are what?
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
Light in a vacuum is the fastest speed
Light between the Casimir plates is less c
Some particles can move through a medium faster than light can move through said medium
The particles are not moving faster than c, just faster than light in that medium.
Strange stuff still happens, but still does not violate c.