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Mysterious Force Affects Pioneer 10 & 11 Probes
JabbaTheFart writes "The Guardian is writing that something strange is tugging at America's oldest spacecraft. As the Pioneer 10 and 11 probes head towards distant stars, scientists have discovered that the craft - launched more than 30 years ago - appear to be in the grip of a mysterious force that is holding them back as they sweep out of the solar system.
Some researchers say unseen 'dark matter' may permeate the universe and that this is affecting the Pioneers' passage. Others say flaws in our understanding of the laws of gravity best explain the crafts' wayward behaviour."
It'd just be great if after all this time we actually find out something like it's not possible to leave the solar system without some sort of extreme propulsion system.
It could be an example of gravitiontational rippling.
a very large gravity well may have a ripple that exists some distance from the center of the gravity well. The sun's gravity well is big enough for us to notice this while the sun and other planets we did not notice it. we MIGHT be able to notice something if we look at the data as these probes appriached and passed juipter.
Do not look at laser with remaining good eye.
From TFA They had been tracking the probes using the giant dishes of Nasa's Deep Space Network.
This doesn't quite quench my thirst for information: does this mean the probes are still sending radio waves/signals, or just irradiating passively?
Sigged!
im not scientist, and surely these articles are written for the layman, but all of the articles i've read say "something more than the sun's gravity is pulling at the probes"
wouldn't the planets, especially jupiter, and saturn, and ALL of the misc tiny asteroids in the various belts, exert a pull on the probes as well? some sort of combined solar system gravitational force since the probes are well beyond the last planet?
doesn't seem that complicated to me, but im definately coming at it from a relatively uneducated perspective then who's saying something's wrong in the first place.
One thing that is rare for them to admit is not knowing why something happens.
According to my physikcs teacher, this is quite often the case. Physics describe how things happen, the question why they happen is left to the philosophers.
Life is just nature's way of keeping meat fresh.
I remember reading a quite striking short story about a crystal shell surrounding every solar system and it can only be broken from inside. It works like a semi-permeable interface, preventing aliens coming /communicating inside. A civilization will only manage to get outside of the shell by breaking the "egg". I can't remember the writer of the story nor the name but I think I read it on either Asimov or Analog in the last couple of years. Can anyone recall this story and remind me of its writer please?
This isn't news. The slowing-down effect has been seen before, on some other probe. I even remember
But expecting /. editors to recall that would be like expecting them to get effect and affect correct.
You cannot apply a technological solution to a sociological problem. (Edwards' Law)
According to this paper, it could be drag from dust in the outer solar system.
Um, I'm way out of my area of expertice here, so forgive me if this is utter drivel.
The probes are basically big lumps of metal moving at high speed through space.
How much do we know about the magnetic fields in deep space?
Could this be some fairly boring electromagnetic effect?
Quidquid Latine dictum sit, altum videtur (anything said in Latin sounds important)
I have no idea whether the effect would be so big though.
Some (Majorana?) even thought some kinds of matter were radiating "pushing gravity", but I'm really leaning dangerously far out of the window by guessing that this is the way that a black hole a the center of the galaxy causes the anomaly in galactic rotation curve that is observed (that anomaly suggests more (gravitational) pull, too.)
Please note that the arguments derived from thinking about Pushing gravity might apply even if gravity is not considered pushing by the physics used.
I'm still trying to figure out what people mean by 'social skills' here.
As a sci fi reader, I of course hope that light speed is a breakable barrier.
As someone who studied physics, I'm not too hopeful. The speed limit isn't the result of a few shaky theories, but rather a pretty deeply engrained part of our understanding. If it turns out not to be true, then most of the physics that has been done for the past 150 years is flat out wrong. It would be like discovering that DNA isn't where the genetic code is held, as disasterous, and at this point in our study, as unlikely.
In Capitalist America, bank robs you!
Has this effect been observed as to the Voyagers?
Excellent illustration (updated daily!) of all these probes and their vitals (trajectories, distance, speed, etc.) at Heavens-Above .
Bush Lies On the Record.
Setting your speed at "c" and it takes a while to get out of the Solar System. Set it at a few AUs per second and you can clear the solar system more quickly, but once you are out, it seems like you are not moving at all. Once you accelerate to a light year per second, things start moving a bit, especially the neighboring stars, but it is still pretty slow going on a galactic scale. If you want to get out beyond the galaxy, I recommend going perpendicular to the galactic plane and accelerating to a few thousand light years per second (ummm...that is rather fast, don't you think).
Doing this gives you a pretty good perspective on things. Once you are in inter-galactic space, if you aren't moving about a thousand light years per second, it seems like you aren't moving at all. For an even better perspective of mixing size and speed, try manually flying back to Sol. It seems easy, and you even decelerate a bit, but it seems like you are going kind of slow until you suddenly zip past Sol doing about 100 light years per second. Go back and try again.
Back to the original point, yeah the speed of light is fast, but on a galactic and/or universal scale, it isn't that fast. I too hope they either find some loopholes in relativity, or find some loopholes in the universe (such as Asimov's idea of Hyperspace), or we won't be going anywhere anytime soon.
Yeah, I know this is deeply in the realm of Science Fiction, but I'm kind of hoping that it becomes Science Fact someday...
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
speaking of gravitational rippling, maybe you can answer a question for me...
Special relativity says there isn't any particular speed that is at rest, right? Speeds are always relative, right?
But gravitational rippling leaks energy until the object is at rest, right? So there must be a rest state of zero speed.. so there must be an absolute zero speed?
I heard other things.
If you read TFA, you'll notice that they are talking about a force acting equally on *both* probes.
Claims that this is a new effect are a bit too early, though.
Occam's razor doesn't mean that scientists should stop investigating because there _may be_ a simple explanation. If there are interesting, unexplained things, one has to go down and calculate every traditional force(/space time curvature) which may act on the spacecraft; numerical simulations of the radiation pressure of the RTGs, taking the geometry of the space craft into account. Other external electromagnetic forces. Etc.pp.
Then, there will probably be a traditional explanation of the effect. If not send some probes out too further investigate the effect. After all, experimental physics is not only about testing the theory's POV, it is also about exploring the world and finding new effects.
You can have wrong calculations by theoreticians even in such fields where there is a fundamental theory capable of explaining everything. (This includes nearly every field of physics today - except nuclear/particle physics and astrophysics).
no we are plowing through space and therefore the deep gravity well of our sun is causing a ripple around it. (so the hypothesis goes, there is no tests done to try and test the hypothesis) It's an effect of all gravity wells, Like Radio frequency transmission has "ripples" off from the center transmission frequency Gravity well could have the same thing kind of like a subharmonic but extremely weaker.
This is all simply WILD speculation. until there are experiments and tests ran that is all it can be.
Do not look at laser with remaining good eye.
As it happens, The Economist recently ran an article addressing some of these issues. The article also provides context and perspective that should be of interest to those participating in this discussion. For convenience, the full text is reproduced below; it is also accessible online (may require paid subscription).
----
Gravitational anomalies
An invisible hand?
Aug 19th 2004
From The Economist print edition
[Image]
An unexplained effect during solar eclipses casts doubt on General Relativity
"ASSUME nothing" is a good motto in science. Even the humble pendulum may spring a surprise on you. In 1954 Maurice Allais, a French economist who would go on to win, in 1988, the Nobel prize in his subject, decided to observe and record the movements of a pendulum over a period of 30 days. Coincidentally, one of his observations took place during a solar eclipse. When the moon passed in front of the sun, the pendulum unexpectedly started moving a bit faster than it should have done.
Since that first observation, the "Allais effect", as it is now called, has confounded physicists. If the effect is real, it could indicate a hitherto unperceived flaw in General Relativity--the current explanation of how gravity works.
That would be a bombshell--and an ironic one, since it was observations taken during a solar eclipse (of the way that light is bent when it passes close to the sun) which established General Relativity in the first place. So attempts to duplicate Dr Allais's observation are important. However, they have had mixed success, leading sceptics to question whether there was anything to be explained. Now Chris Duif, a researcher at the Delft University of Technology, in the Netherlands, has reviewed the evidence. According to a paper he has just posted on arXiv.org, an online publication archive, the effect is real, unexplained, and could be linked to another anomaly involving a pair of American spacecraft.
Three different types of instrument have been used to detect the Allais effect. The first are conventional pendulums, such as the one Dr Allais used originally. The second are torsion pendulums, which work by hanging a bar that has weights at each end from a wire. As the wire twists back and forth, the bar rotates in pendulum-like motion. The third are gravimeters, which are, in essence, very precise scales. All of these instruments measure the acceleration due to gravity at the Earth's surface, a quantity known as g. The Allais effect is a small additional acceleration, so tiny that it would take an apple about a day to fall from a tree branch if it were the only gravitational effect around.
Allez, Allais
Dr Duif has examined various conventional explanations for the Allais effect. He finds the most obvious suggestion--that it is a mere measuring error--unlikely, because similar results have been found by many different groups, operating independently and, in at least one case, without knowledge of Dr Allais's results.
He also discounts several explanations that rely on conventional physical changes that might take place during an eclipse. One of these is that the anomaly is caused by the seismic disturbance induced as crowds of sightseers move into and out of a place where an eclipse is visible. That seems unlikely, given that one of the experiments with a positive result was conducted in a remote area of China while another that had a negative result took place in Belgium, one of the most crowded parts of the planet. Dr Duif also considered the possibility that, because the moon's shadow cools the air during an eclipse, this cooler, and thus denser, air might exert a different gravitational pull on the instruments. This change could, he reckon
Gravitation rippling only happens to accelerating objects, so it does not violate relativity. It works the same way as brensstrahlung (ie., breaking radiation). It is believed that accelerating objects emit gravitons (gravity particles) in the same way accelerating charges emit photons (electromagnetic particles). The braking is relative to the object causing the acceleration.
Hmm, I've read about this on Slashdot before, and I'm pretty sure I've read about Modified Newtonian Dynamics before.
The gist is this: MOND is an alternative to the "dark matter" explanation. It makes a modification to newton's laws of motion, whereby gravitational strength.
The equation F = ma is well known, but with MOND the gravitational inverse square law changes to an inverse linear law when the acceleration due to gravity falls below a critical value, which is very small (i.e. you get pretty far away from the source of gravity).
This explains most of the observed behavior that is currently explained by dark matter, including the rotation of galaxies which seem to defy newton's laws. Unfortunately, there's still no derived theoretical basis for MOND; as of now it's a rather arbitrary explanation with equations that just seem to work pretty well, and many physicists do not take MOND seriously. Then again, "dark matter" seems just as silly.
A more in-depth explanation is available here.
Interestingly, the MOND critical value for the acceleration (a0) turns out to be the speed of light divided by the age of the universe.
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
MOND
/.
Well, it's what some physicists may be thinking, anyway. I suspect that the Guardian article is meaning to hint at this, as well. For those who don't know, MOND is a modification of standard Newtonian Dynamics that has to do with very small accelerations. I'd actually really, really like to see a MONDian calcuation of what the forces should be on those probes and see if it matches their current paths.
Wow. I think this is the second time I've advocated MOND (a theory which I just barely consider reasonable, and no where near verified) on
I couldn't tell if you were experimenting with poor-man's cryogenics or looking for the orange sherbet.
Oh, and see my journal for more ranting on the subject (it looks recent, but it's actually 1 or 2 years old).
I'm not a rocket scientist, but I wonder if this is one of the effects of passing through the heliopause. It sounds like Pioneer 10 and 11 are too weak to send any actual data these days, so they can't really report if they're coming in contact with the expected particles, for instance.
Then again, it appears that this effect has been noted since at least 1998, so it's hard to say what's really going on. I will note that the two spacecraft are spin-stabilized, so maybe there's some weird frame-dragging-esque effect going on. I guess the effect hasn't been as noticeable on three-axis stabilized craft, though that's kind of expected since they would more frequently be using thrusters to change orientation (which would probably slightly affect trajectory too).
Personally? In German the field of engineering is called "Ingenieurwissenschaften", i.e. engineer sciences.
The Tao of math: The numbers you can count are not the real numbers.
The casimir effect cannot exist, as I understand it, on large scales like that. Its a force that results from the interesting effects of bringing two conductive surfaces so close to one another that only certain wavelengths of virtual parties can exist between the plates, whereas all wavelengths exist on the other sides of the plates. As a result, there is vacuum pressure pushing the plates together.
Its worth mentioning that yes, this could be used to extract energy from the vacuum, although no one has figured out (a) how to do this on a large enough scale to be useful and (b) whether it would take more energy to position the plates than you could extract (see below).
Logically, the energy to seperate the plates from one another should equal the energy gained by their collapse together due to vacuum pressure, so that should mean this is no net-gain.
"Stumble before you crawl"
No, the singularity has finite mass. It has infinite density, but that's because it has zero volume.
Of course the black hole has not zero volume, because the term "size of the black hole" doesn't refer to the singularity (which might not actually exist; you can't just go into a black hole, look if there's a singularity inside, and come out again), but to the event horizon (which is the border of the region from where you cannot escape, nor can anything else, including light).
The Tao of math: The numbers you can count are not the real numbers.
The original paper on the anomolous acceleration came out, I think, in 1997 (I reviewed it in a graduate astrophysics class I was taking around then). The authors did a good job of discussing some of the possible explanations for the discrepancy, including leaks from the craft, dark matter, 'modified newtonian dynamics' (MOND), and others which I can't remember. None of the explanations they came up with really explained the magnitude or direction of the effect that was observed.
A little while after the paper was released a researcher pointed out, in a short, concise, article, that assymmetry in the way radiation from its ever-weakening energy sources (the RTGs mentioned) reflected from the craft, especially from the main communications antenna produced an acceleration of roughly the right magnitude and in the right direction.
It would have been great if MOND had provided the explanation (MOND has been proposed as an alternative to the bulk of the dark matter content in galaxies - not as an alternative to the content in the rest of the universe, though): I like observations which throw a wrench in our usual way of thinking about the universe - it makes things much more exciting. =;-)
#include "cunning_plan.h"
Actually, you're mistaken. It has infinite density not mass: theoretically a simple singularity has zero volume, thus its density is whatever its mass M is, divided by zero. That results in an infinity (and is why, actually, its called a singularity, a math term).
Moreover, there are no simple singularities, even in theoretical GR. According to Kerr, it can be demonstrated that all black holes [if they exist] have a "ring singularity" at their core, not a point singularity. The reason is simple: black holes rotate. If you have a point singularity w/ zero volume, there is no means to differentiate a rotating body versus a non-rotating body. Mathematically and conceptually, Kerr demonstrated that this means that singularities actually distort into a zero-thickness torus called a ring singularity (with its plane lying on the plane of rotation of the black hole). Inside the ring, it seems, there would be a tear. This was even realized by Einstein, and is the birth of the concept of an Einstein-Rosen bridge (and the subsequent dialog about wormholes/white holes).
"Stumble before you crawl"
Couldn't it be continuously hitting against clouds of dust?
How close are these probes relative to the Oort cloud? I would think that what we are witnessing is that the probes lack the velocity to escape and will eventually become part of the Oort cloud.
"I bow to no man" - Riddick
From the script of the first episode: From this it can be deduced that the maximum warp that the new engine was designed for was warp 5, but they were going to be testing out warp 4.5 for the first time.
If you use warp 4.5 = 91.125*c for 4 days you get 0.998 light-years. This is so close to a light-year (possibly rounding issues) that the writer who came up with 4 days probably forgot to multiply by the number of light-years to Kronos.
Even if you use warp 5, you get 1.37 light-years. Considering that Alpha Centauri is 4.4 light-years from Earth, the 4 days at warp 5 idea still sounds absurd.
Let's go Hurricanes!!! 2006 Stanley Cup Champions!!!
As everyone knows, spacetime is like a great black ocean criss-crossed with a bright blue grid, save only that this representation is in two dimensions (plus time), while the actual process happens in three(plus time). Significant masses float and bob on this ocean's surface, sending out ripples which distort the blue grid. These masses also happen to vibrate at the frequency of their mass, the accumulated harmonics of thier myriad energetic constituents and inertial qualities.
Just like a ripple on the surface of a liquid, by the effect we call gravity there is a trough-and-ridge structure surrounding the object in space time. These structural feature effects on spacetime are governed by such factors as the surface tension (E=mc^2), viscosity (planck constant) and temperature (CMB limit of ~3 Kelvin) of the continuum, the bouyancy(mass), size(volume) and speed (velocity) of the object thus placed.
The trough represents gravitational attraction, but the ridge describes a net negative effect (in other words, "anti-gravity").
Both the trough and the ridge have an average 'height' equal to the actual surface level of the surrounding medium, but the trough seems much deeper than the ripple seems tall- that is to say, the apparent gravitational attraction is far greater than the anti-gravital effect of the ridge. This is a very simple function to describe, it is commonly understood as the inverse square law of proportions (Newton). The main trough has much less area to find expression, being confined to the immediate area surrounding the object, while the ridge has the greater area to affect distortion, thus the appearing much weaker.
This effect seems almost invisible at our local scale (though numerous experiments have confirmed it), namely because of significant local interference (turbulence), which appears mainly as slight variations of gravitic potential, though which also lay in the trough of our host star, thus loosing again a significant proportion of inherent amplitude. It is curious to note that these ripples have heretofor been attributed to such things as 'groundwater storage' and 'ice coverage' on the surface of the planet Earth, a reasonable supposition about the variance in planetary mass, but a ridiculous consideration regarding system-wide gravity effects).
As these probes wend their way starward, they must cross over the features created and accumulated by the disturbance of our solar system. Just like watching a piece of driftwood tossed around by the tide, the probes must express curious responses to these forces.
By way of a final note, let me just say that there is much yet to be said on the secondary effects of this phenomenon, namely the interference patterns created by a large system in motion, the cumulative effects at scale, the 'apparent' expansion of our universe and the ramifications of the structure known as a 'black hole'
Signed,
Professor MOMOCROME
-1 Dead series reference
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
http://www.spacedaily.com/news/voyager1-03c.html contains some interesting data that may be a clue:
:-) ).
"The location of the heliopause, which marks the outermost edge of the solar system, is a subject of scientific speculation. In two papers recently published in the journal Nature, scientists debated whether Voyager 1 has already reached the termination shock, a sign that the heliopause may be near. The termination shock is caused by a reduction in the speed of the solar wind as it slams into cooler plasma at the edge of the solar system and is similar to the sonic boom that occurs on Earth when an airplane crosses the sound barrier."
So my guess (IANAAP) is they have lost their (solar) wind in the back they had and hence the decceleration. It may not be so simple, though. Perhaps the space on the inside of the heliopause sphere is constantly "sweeped" by solar wind and therefore might have lower density then surroundings (picture: we are in a kind of a solar bubble!
There is a way to put my hypotesis to test: check the temperature readings for signs of friction, or perhaps even cooling.
You say the writer screwed up the calculation, I say he conveniently forgot to do the math and worked in 4 days based on his storyboard timeline. Sure they could imply dead days but that makes the action seem much more spread out which can kill the pacing and energy of a show.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Some of the novels (I know, non-canon...but like anybody seriously accepts "Enterprise" as canonical) claim that the old warp 4.5 limitation was due to the lack of dilithium to focus the warp field. Once dilithium was introduced, warp 8-12 became possible. And even higher, when alien races take over the engine room and make bizarre modifications to Scotty's "wee bairns".
Constitutionally Correct
gaining mass by gathering dust?
bj
What if the probes are actually encountering drag of some type. The sun has been blowing out particles in the form of solar wind for about 6 billion years. What if the these particles do not escape in to interstellar space as thought but instead go into orbit around the sun at about this distance. Over the billions of years these particles could build up till flying a spaceship into this area would slow it down and change it's direction.
If solar wind couldn't explain it what about left over gasses from the formation of the solar system? Theory states that the sun blew away all these gases from the inner solar system but what about outside? There has to be a region where these gases would still exist.
But ether from the effects of solar wind or left of matter from the begining of the solar system the effect would be the same. Inside the solar system space would be realitivly empty where the effect of solar wind, gravity from the planets, and light pressure from the sun would keep it "clean." Outside the solar system there would be an area where the gases form a shell around the system. These gases don't have enough energy to escape the suns weak gravity so they just stay there building up over the years.
In effect the probes would be hitting areas of space where the gase is more dense. If present in enough quantity it would slow the ship down. What about the voyager probes? Are they experincing the same effect?
Supporting World Peace Through Nuclear Pacification
Humankind's challenge is to evolve into something that can cross interstellar distances and colonize other solar systems efficiently. How this is to be accomplished (biomechanoid, or some other exotic technologies which are beyond our understanding) is an exercise left for future generations. Arthur C. Clark thought the same in The City and the Stars (et al) with the massless mind "Vanamonde" and his peers.
If such a species had already evolved, and FTL was available to it, we would be a sitting duck (assuming that we had desirable resources). As it stands, there is a great deal of time that must pass for such a species to reach us (hopefully).
The time required for interstellar colonization is nature's way of forcing us to be thorough and consistent, and to make many of our errors early on, perhaps before the effects upon our survival become critical.
Of course, this outlook for our initial stages of colonization must span hundreds of thousands of years. We might end up wiping ourselves out due to our infantile handling of the global ecology long before then.
But it's nice to have goals.
Measure the speed of light in two directions: parallel and perpendicular to the direction of motion of the Earth in its orbit. Compare the two to discover whether or not the Earth's velocity is added to that of light.
And guess what? It's been done.
Real Daleks don't climb stairs - they level the building.
Everyone seems to be operating under the assumption that a force is acting to push the probes closer. What better describes what is going on is that the probes are no longer being influenced by an outward force (perhaps solar wind). So lets say theoretically that the sun's gravity as we observe it is Gsun. But with this additional force now detected, we're really seeing Gsun = Gactual - Fnew.
The laws of physics don't just stop working. More likely, we just aren't observing the phenomenon correctly.
The answer is Archer was estimating and the actual time to Neptune and Back is under 6 minutes. Remember, it's pretty damn hard to turn a vehicle that is travelling at warp speed. They'd have to disengage, turn, and replot a new course for the return trip.
Actual time at 4.5 warp would be well under six minutes. Travelling at 4.5 warp for 4 days would cover much more distance than our little '6 minute' scenario would lead anyone to believe.
No I'm not a star trek geek, I just like playing devils advocate.
peace,
-Grokent
One of my favorite demonstrations from Physics class was when my teacher accelerated a ring of (non-ferrous!) aluminum into the cieling (nearly broke a light fixture) using an electromagnetic field.* This was the same day as he showed various non-ferrous pendulums being slowed to a stop in a fixed magnetic field due to eddy currents created in side the pendulum.
Moral of the story is that, even absent influences such as gravity and friction, a fixed magnetic field can change (slow) the velocity of a non-ferrous metallic object. Granted, though, you have a point about the fast drop in intensity with distance for magnetic fields...
*I don't remember how the device was constructed, or if the teacher even bothered describing it in detail. All I remember is that it plugged into 110 V AC, had a button he'd press, and it buzzed rather loudly while the button was pressed. The aluminum ring was shot into the acoustic tiles in the 20-foot ceiling hard enough to damage the tile, and the teacher admitted that he had actually broken a light fixture in a previous semester. Since then he aims more carefully.
"Space Exploration is not endless circles in low earth orbit." -Buzz Aldrin
That is what I though you were referring to. It's really only a Wild Ass Guess. Yes even Mr. Hawking makes those in the face of extremely little research and data.
first off Gravity is nothing like any other kind of energy output. In fact it is still pretty much undetectable on it's own and we can only detect it by it's effect on objects, it can not be detected directly. Calling it an energy output is stretching it to fit a current understanding.
gravity needs to be looked at differently, it's not an "output" it's an effect. Gravity is a side effect of mass. I can not have a mass the size of earth without gravity simply because of the distortion that mass has on the fabric of space.
Therefore, looking at gravity and any ripples that may or may not exist around any gravity well can not be looked at as an energy output. The gravity ripple I am describing is like that of the rings of saturn. they simply reside there. the ripple of gravity that I am proposing to exst outside the oort cloud that is directly or even indirectly having an effect on the spacecraft is probably static (or fluctuates with the gravity well's fluctuations)
The only example I can come up with is that the fabric of space is not simply a "rubber sheet" that many use to explain a gravity well but more of a fliud bath that has a very high specific gravity. the displacement of a gravity well will have to go somewhere and may manifest as a gravity ripple "sphere" that encircles the gravity well at a specific distance and strength determined by the size of the gravity well. (we have to think in 4 or more dimensions, and this is where many people get lost)
That is why I think someone needs to carefully study the data of the probes as they approached and departed Jupiter and Saturn to see if anything is detected. (granted the radius of the ripple of Jupiter may be well inside the earth orbit) although the size of Jupiter is significantly smaller than that of the SUN and therefore will have a significantly smaller ripple strength and size, and may be undetectable from the data.
Do not look at laser with remaining good eye.
It is not necessary for a black hole to be of infinite density... It merely needs to be of sufficient density to fit within it's own Schwarzchild Radius (the distance at which the gravitational field becomes strong enough to prevent all light from escaping).
All massive bodies have a Schwarzchild Radius... But most bodies are too "fluffy" to fit inside it and so they don't form an event horizon.
Matter can degenerate very far before it can fit inside it's SR... electron degeneracy, neutron degeneracy, and even quark degeneracy are all forms of superdense matter which is still too fluffy to form a black hole. (I believe a good candidate for a quark star supernova remnant was found a couple years ago.) It is possible that there is another level of degeneracy below quarks where matter crosses the "Schwarzchild Density", exposing an external event horizon, and yet stops condensing down to infinity...
One theory I've heard is that perhaps that level is string degeneracy... Maybe black holes are some solid condensate of strings (in some form other than quarks) beyond which matter can't condense any further. The idea is that the supernova remnant always ends up with a finite radius but one so small that it fits inside it's event horizon. We would never be able to see such a condensate because any chunk of it would always have an event horizon around it.
The whole "infinite density singularity" and "divide by zero" thing seems too sloppy for the actual universe to me. For one thing, it seems to me that it violates the Heisenberg Uncertainty Principle, mandating that the non-zero mass black hole have infinite energy.
On a side note... regarding the "infinite mass" thing, people seem to have this idea that if you get anywhere near a black hole, you will get sucked in... As if BH's are kind of gigantic vacuum cleaners or something. In actuality, black holes start out at about half the mass of their original star (those that form from supernovas). They don't have any more gravity than half of what their seed star had. So you can hang out in orbit around one just fine. The super gravity of black holes only comes to play when you get really really close to their center of mass... much closer than you could get when the BH was in it's original star form.
wag more
bark less
Ok so what you are saying, or what this implies, is that a black hole doesn't actually *have* zero volume, but rather its volume is continually decreasing toward zero without actually reaching it?
What the other poster said is true, but also the trick is that saying the density is 'infinite' isn't really specific enough. There's a whole field of research in maths of infinity, which I thankfully haven't strayed down just yet.
Basically saying a value is 'infinite' is just saying it approaches some unattainably large value, but doesn't tell you about how 'fast' it may be approaching it (this is easier to visualize if you picture a function going to infinity along some axis, rather than one specific point).
So basically in your above post saying infinity = infinity was the mistake in your logic. Not all infinites are created equal, is the really mind bending thing.