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Scientists Find Evidence of Black Holes Sucking
Sawopox writes "A bunch of guys a lot smarter than I am managed
to find evidence of matter being sucked into a blackhole at roughly 6.5 million mph. " Yeah, but what kinda mileage does that matter get?
So does this mean that matter can travel faster than light? Why of course it does... :)
Well, if you're starting from rest (i.e. zero kinetic energy), it's actually an infinite percent increase in KE, but that wasn't my point (besides, it's the *total* energy that's increased by just 0.005%). Consider this: accelerating a 1 kg object to 0.01c will require 4.5x10^12 joules of energy. To put things in perspective, that's 1,250,000 kilowatt hours. A typical household uses around 1000 kWh per month (that's a rough figure). So the energy needed to get that 1 kg block up to 6.5 million mph could power a dwelling for over 100 years! If you ask me, that's pretty impressive.
Actually, gravity is merely a manifestation of the curvature of space-time (if we believe Einstein), so it is not "created" in this sense. It is "caused" (this is bad terminoligy) by the mass concentration of every piece of matter. So, yes the pen "attracts" you (meaning, that it curves space time, but not enough so that you are drawn to the curvature. Actually, you "attract" the pen far more than it "attracts" you (you have a much greater mass)
About the whole acceleration thing, it's a vague memory here, but apparently the object that undergoes acceleration experiences the time dialation.
You're thinking of the twin paradox, most likely. Here it is, in one phrasing:
The solution to the paradox is, as you observed, based on the fact that one of the twins underwent acceleration, whereas the other did not. But I'm dredging this up out of my memory from my undergraduate physics courses, which took place a few years ago -- so I can't cite the full details.
light speed is actualy..... 300,000 feet per second per second.... i dont' know where ya'll are getting these other #'s....
Speed is measured in units of distance/time. "Distance over time" -- not "distance over time over time". Your figure of 3x10^5 ft/s^2 would be an acceleration, not a speed.
The speed of light, to 3 significant figures, is 3.00x10^8 m/s. You can convert that to whatever units you like.
What makes a black hole is not a certain amount of mass, just a certain amount of mass concentrated within a certain area. There's a certain critical density, you see.
Assuming you could pack the matter tightly enough, you could make a black hole massing only a few grams or less. In fact, for practical reasons, a laboratory-created black hole probably wouldn't have much more mass than that.
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DNA just wants to be free...
for us 'merkins
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DNA just wants to be free...
according to the BIG Bang theory, the universe was once as small as a pea. All that matter in so little space = enormous gravity. And I do mean _ENORMOUS_. But then, it exploded. Gravity didn't do shit all to prevent it. I guess it was on a coffee break...
Gravity literally didn't exist prior to the big bang (or for a short period afterwards), nor did mass.
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DNA just wants to be free...
Oddly enough, falling into a black hole is one of the most efficient ways to get energy out of matter (the only better one I know of being to react it with antimatter). You get something like a third the e=mc^2 energy with the black hole, compared with 1 percent-like numbers for nuclear and 1e-10 for chemical fuels.
Here's a slightly more technical report on this from the BBC if anyone is still interested.
I'm just a CS student, but it still sounds pretty reasonable. Element compositions and temperature determine the wavelength of light that will be emitted from the matter. For generic space debris/gasses, the spectra tend to be pretty simple, so we can determine their composition by looking at which frequencies are emitted. Overall variation from the expected wavelengths are caused by the doppler effect (red/blue shifts). (sorry for the physics lecture)
There's really only one cause for 'bogus' redshifts: our expected wavelength for a given band isn't really the right wavelength (i.e. we think we're looking at a shifted band from helium instead of a slightly-shifted sodium band).
This misinterpretation probably won't happen. Relative to earth, matter is moving into the black hole from all directions, one half producing redshifts, the other producing blueshifts, and the region in between producing no shifts at all.
The region producing blueshifts (matter coming towards both us and the black hole) won't really be seen, because it's "behind" the black hole, and its light generally is absorbed inside the event horizon. But we'll still have emissions from matter moving perpendicular (no shift) and away from us (redshifted). We therefore have a background spectrum to compare the redshifts to, and can thereby rule out other sources.
Finally, those speeds are also reasonable. Stuff that we rocket into space can travel over 100,000 mph, and we can do that with the Earth's gravitational pull (Cassini does this tomorrow). Black holes have some serious pull ;)
Anyway, even if a black hole had really strong gravity, that doesn't mean it would "suck in" the whole universe. Gravity is attractive, but that doesn't mean that things will always travel toward something with gravity. Planets orbit the Sun rather than falling into it, for example. (Of course, in the long term their orbits would decay.)
If two black holes collide, you get one black hole and a bunch of gravitational waves.
That's where the aliens are. Better form a government committee to investigate ;)
black holes are just really heavy chunks of stuff. there is no other side. You just eventually smack into a chunk of stuff.
-I go to Rice, so figure out my email address
It won't go through the floor if you put it in orbit. You also won't have to put brakes in your car.
99.99...% of c would still take you over 4 years to get to the nearest star. Hardly a "sneeze"
TheGeek
http://www.geekrights.org
TheGeek
http://www.geekrights.org
Kill the monkey
Would the matter make a good beowulf cluster?
ahhh yeah, that sounds like it
:)
:)
wooohoo i'm not completely insane
glad to know my incoherent ramblings about incoherent ramblings are familiar enough to get a coherent statement out of them
Need a Catering Connection
Maybe it's beacuse most of my friends (and me included) learned BASIC as our first programming language. Hmm....In fact, I bet a lot of geeks learned like me, with an early version of DOS (2.0) and an Apple IIE (sorry, I was 5, I couldn't program in Binary or Hexadecimal yet!!!) learned to program BASIC.
That's my 1/50 of $1.00 US
JM
Big Brother is watching, vote Libertarian!!
--Justin Mitchell
"2nd Place is a fancy word for losing" --Bender (Futurama)
>>Yes, I've got a device that shoots out particles at damn near the speed of light - a torch ;)
Er, your torch emits photons AT the speed of light. A flashlight would do the same thing.
I was wondering if anything else could account for the redshift in the matter that they saw. I don't doubt the scientists, there's just something about that I can't put my finger on that feels a little weird. Not a physicist (or a good speller), just curious.
The title to your reply fits your posting perfectly.... Utter BS!!!
Doesn't matter, its all downhill.
the AC
Hemos is like...sci-fi fans;he thinks technology is cool, but he hasn't bothered to understand the science it's based on
NO,NO,NO!!! You would ripped apart (stretched) due to the gradient from the tidal forces. Oh, and don't forget exposure to high levels of radiation being emitted from the accretion disk.
well, since the matter is powered by gravity, which is caused (created? what's the word here? I didn't major in physics ) by the matter inside the black hole and a *lot* of matter is required to create gravity, I'd think you'd get the mileage (which I'm assuming to mean miles per x amount of fuel) by dividing the mass in the black hole by the combined distance traveled by the mass of the matter being sucked into the black hole, and since there's a *lot* of mass needed to make that much gravity, it's possible that my 1980 longbed pickup gets better mileage
I'm going to go find a life now.
Here in L.A. it's the Black Hoes that do the sucking! I know, a bad attempt at humor.
Well, since nobody else has said anything relevant,
I bought "The Black Hole" last week, so I guess I should watch it now.
Pope
It doesn't mean much now, it's built for the future.
I'll second that =)
LRJ
Very slow. Light travels at 186,000 miles a second, so that in hours would be...........669,600,000 million MPH.
at that speed you wouldn't feel it coming. You would be crushed before you even felt yourself being pulled towards it.
---Got Coffee?---
No, I'm really not smart enough to be authoritative on this, but I'll give it a shot:
/. populace.
Black holes aren't really "black." Stuff come out of them. That how they first discovered them a few years ago, by the radiation spewing out of one. If I remember correctly:
In empty space particles and anti-particles can be created and distroyed from essentially nothing (meaning no net change). If this happens right outside the event horizon one particle escapes while the other does not. It rushes off. While interesting, that doesn't seem to be getting me anywhere.
How about Hawking radiation? Black holes should have a non-zero temperature. Faster than light travel being possible allows radiation to escape, which is what has evidently been observed (no, I don't have a link handy). Black holes evaporate, supposedly. I suggest someone with more knowledge correct me before I inflict myself further on the general
Yes, but it is scale that matters. At synchrotrons, electrons hit 5-7 9's or so (.99999-.9999999 c), and protons can be accelated to tremendous rates (a few 9's) as well. Accelerating a kilogram of matter is a vastly, vastly more difficult procedure. Think of it instead of the kinetic energy that the matter has. Each kilogram has a kinetic energy of ~1*10^13 kj. This is equivalent to combusting 10^7 moles of octane, or 6*10^5 kg of gasoline.
I think it is about enough to vaporize one olympic size swimming pool of water. Consider, however, that a good fraction of a stars mass is accelerated, this is a number on the order of 10^30th kg, so the total energy is of the order 10^43 kJ. That _is_ alot. That is about enough to vaporize the earths ocean 10^20 times, or the entire solar system 10^10 times, give or take an order of magnitude or two
To observers outside the terd. Yes, it would take 4 years time to travel to the closest star. But, The terd itself would only experience a few days time because of the time compression effects at relativstic speeds.
The black hole should be running Windows. Then it would suck MORE.
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Win dain a lotica, en vai tu ri silota
But it's not operating in a vacuum...
Whatever happened to LISA?
It was a proposal to build a space-based zero-drag iterferometer for observing gravitational waves (eg colliding neutron stars) that would follow the Earth by orbiting at one of the La Grange points in the Earth's orbit...
I'm out of my tree just now but please feel free to leave a banana.
actually, the light has no trouble moving around just as fast as ever, whether it's inside or outside the event horizon. It's just that space inside the edge of the hole is curved so badly that it spirals right into the singularity. Outside the hole, space is merely slightly curved, so that the light (when it follows the geodesic) can move away from the hole. It's not really "escaping" or even trying to. Light just follows the various "bends" in spacetime.
Looks like a reply to this comment got sucked into a black hole.
I try to remember that people who deal with their area of specialty do have experience with things which are novel to me. Just last week I noticed there were two astronomical research projects with similar purposes operating independently. I was able to connect them, and left them to figure out for themselves how their differing techniques benefit both of them. They know how to do their jobs.
>If two black holes collide, you get one black hole and a bunch of gravitational waves. Assuming they do not collide directly. The gravitational waves are created by the black holes orbiting one another, the orbit shrinking and speeding up until they coalesce.
void post { post_random_comment("slashdot.org"); karma--; }
According to my calculations, my jizz leaves my penis at 0.0000093 c.
Don't loose your temper - its only spelling. :-)
I've always known black holes suck...now there's proof! :-)
My journal has hot
Accretion disks, almost by definition, are direct evidence of matter being sucked into a massive object, black hole, neutron star, white dwarf, etc. What the article doesn't say is that accretion disks are so hot and dusty that we haven't been able to see what's going on inside them. The finding of Doppler-shifted light allows us to determine, experimentally as opposed to theoretically, the speed of matter within the disk.
Light is not "sucked" into a black hole. It is red-shifted by the gravitational field. Any light that crosses the event horizon is red-shifted to undetectablity by the time it leaves the gravitational field. Light can also be "bent" by going near the strong gravitational field.
Current theory allows for Hawking radiation to escape, at a rate inversely proportional to mass. Black holes of small mass should lose energy so quickly that they explode.
The "tiny region" is relative. The more massive the black hole, the greater the radius of the event horizon, and the more even the gravitational gradient at the event horizon. It is possible that our entire universe is contained within the event horizon of a gigantic black hole. Current theory has difficulty explaining what happens to matter inside the event horizon. The density of matter inside a super-massive black hole would not have to be that great.
Light is not red-shifted as it "speeds away from the Earth", except for a very minor gravitational effect. Red (or blue) shifting is due entirely to the relative velocities of the observers.
Since the speed of light is constant, one must assume that they mean the red-shift from the light indicated that the matter was moving along at this speed relative to "stationary" gas of the disk.
The only way scientists have been able to ``see'' them up to now is by looking at the accretion disks
"How old are you in light-years?" "Why, about 30 feet."Or by observing the wobble of a star paired to a singularity. Other, so far unsuccessful, possibilities include observing gravitational lensing effects, and gravitons.
actually IIRC from when my calculus based physics teacher was rambling on and on and i was generally not paying very much attention.....
Time compression only happens when there is relative acceleration between the two frames of refrence (the 'terd' and the earth), so for the duration of the trip (at a sustained velocity one would assume), the advancement in time is the same for both frames......
What that means, i have no idea
Need a Catering Connection
since black holes are exerting so much gravitational force, this would have to be an incredibly "rigid" city. i think impossible by any technological standard, since black holes would possess enough pull to tear apart planets and stars. now, i can lessen the criteria to naturally occurring black holes as they require immense mass to occur ... and i could theorize it is possible to create smaller ones than the natural ones, but it is well beyond us at this point.
Welllllllll Mabbby. You also have to consider that time would be going much slower in your pants than in your brains. So maby your head could keep up with your pants. But it's been too long sense I took my physics courses, and I don't care too look it up again. Anyone care to do the math, would time slow down relative to position to keep you intact? (Not the mention the fact that to an outside observer you would never reach the center.)
Bravo! That was a very well planned attempt at fooling us into believing that you actually know what you are talking about by using BIG complicated words! Nice job! You have an extremely well developed vocabulary! Sorry, but it didn't fool me, but since nobody else is going to argue with you I assume that everyone here is a computer geek who knows nothing about physics or astronomy, and yes, I am an anomymous coward, and I am proud of it!!!!!!!!!!
that enough people don't know what a light year is that Yahoo felt compelled to explain it in the article.
In this universe black holes suck; in another universe, they rule!
---- "If we have to go on with these damned quantum jumps, then I'm sorry that I ever got involved" - Erwin Schrodinger
Well accually we guess mass of stars based upon how they affect other stellar objects. And to figure that out we have to figure out the mass of the stellar objects its affecting. Ultimatly the mass of most stars have been figured out, but honestly its alot of guess work. Pretty damn good, scientifically based guess work, but never the less alot fo guess work.
I forget who to attribute this idea to but here it is in a condensed form:
You build a large city around black hole that is circular in cross-section from any particular reference around the black hole (or non existent for part-spheres). If your city is rigid enough it won't go crashing into the black hole. Now have people live in the city. Lots of trash. Fill up a cargo ship with the trash and undock it. Let the ship descend relatively close (for a ship of course) to the event horizon. At this point release all the trash (as in detaching 95% of your ship) and soar away. The important thing here is that you are travelling tangentally with the event horizon so that the trash drops off in an almost direct path to the black hole and your ship travels in an upward arc toward your space station. Once you recapture the energy of the ship (which will be VERY economical if I remember correctly) you shouldn't have too many power requirements for your city. You'll have to remember to bring in alot of materials to make alot of trash.
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.
I am no scientist, but from what I hear is that the potential force that existed in singularity outweighted the gravitational force being exerted. Basically you had what was a spring that was being wound tighter and tighter until the force of that spring pushing out was greater than the force pushing in till it finally split, suppositivly the force was go great that the singularity, or whatever you want to call it, litterly turned inside out, and errupted into our universe.
>Wouldn't a Blackhole eventually consume
:-)
>all the matter in its galaxy?
I sort of doubt it since, as somebody else pointed out, the black hole would have no more mass than the stars it picked up so that stars in the arms would probably just stay in their orbits. The high energy radiation from the collisions of the matter as it got sucked in might give you more than a nasty sunburn if you were in close enough. Tidal forces might trigger novas in large suns as they got closer in which also wouldn't be too healthy.
>And then wouldn't it start sucking in other galaxies?
Not unless they were already on a collision course. I read something recently which gave
me the impression that that's a relatively rare occurence nowadays with the expansion of the universe, but that it was more common in the early universe.
>What happens when 2 blackholes collide?
Actually, I knew Jonathan Thornburg at the University of British Columbia, while he was working on his PhD thesis with that very subject. It took him a while longer than usual to complete it but (thinking about it) maybe he was just stalling for time until the computers got fast enough to do the number crunching. Jonathan had a combined CS and Astronomy background so (he claimed due to inspiration by some AI courses he took) he created a language for describing the mathematical interactions, and then wrote a compiler for it which generated C, with loop unrolling and a few other tidbits. He also created some tools to analyze the output which created pretty pictures. This was about 8-10 years ago so my memory is a bit vague, but you could probably order a copy of his PhD thesis from the UBC library if you're really keen on it
>Do astrophysisists need to have good spelling and gramar?
Well, UBC expected everybody to pass an english competency test after first year. The test required you to demonstrate good spelling and grammar and basic expository skills in writing a composition and a precis.
Most of the science students got through on the first try, it was the engineers who were notorious for repeating the test 1 or more times. I am not sure how the standings were within the various science branches, or how the science faculty compared to the business or arts faculties.
Most academics realize after a while that if you want others to read what you publish, the onus is on you to make it readable with good grammar and spelling. There aren't many jobs for astronomers outside of academe. Thus...
Did you know that black holes have no hair?
Laissez lire, et laissez danser; ces deux amusements ne feront jamais de mal au monde. - Voltaire
Of course, this information was actually dug up by Ken Starr as a part of the impeachment hearings...
Actually, the previous poster was right.
.9999...c. An observer on earth would calculate a much different number of cycles per second.
.9999c is almost like that. Time for the object flows very slowly to an outside observer.
Think of a photon bouncing between 2 parallel mirrors. Someone looking at that would count a certain number of cycles per second.
Imagine if this contraption were on a space ship flying to the nearest star at
About the whole acceleration thing, it's a vague memory here, but apparently the object that undergoes acceleration experiences the time dialation.
As a simpler case, picture an object traveling at the speed of light. Since nothing can travel faster, nothing in the object can move... no time. Traveling at
Time is relative. See my post above.
As you approach the speed of light in a given direction, the universe also contracts in that direction.
Relativity is very messed up. But, given enough energy, relativity does say that you can cross the universe in an infinitely small amount of time (relative to yourself).
I feel competent to comment on this...
Black holes do not suck, any more than vacuum sucks. It just irritates me when people say that.
Science doesn't suck. It blows.
since black holes are exerting so much gravitational force, this would have to be an incredibly "rigid" city. i think impossible by any technological standard, since black holes would possess enough pull to tear apart planets and stars.
No problem. The key here is distance. A black holde will rip apart a star that gets too near. We are not ripped apart by distant black holes, and a city built on a ring/sphere around a black hole will do just fine with enough distance. A star-sized black hole would of course force a city-ring similiar in size to the solar system...
As far as I know, the Large Hadron Collider at CERN will collide two 5 TeV streams into each other. That's a lot of energy. Even older particle accelerators like the one in the facility I work at, TRIUMF, can do 75% of the speed of light. BTW, TRIUMF is now home to the most intense radioactive beams facility in the world! Book your experiments now for a low, low price of only three million dollars. Space is limited.
Wah!
well, my rough quick calculation give 0.01c, but it's still pretty fast.
GRH
I believe light speed is roughly 3x10^8 m/s or 186,000 miles per sec for you non-metric wanks. :)
- Strangely enough that comes to 6.696 billion miles per hour. I suppose the light is trying to escape and is slowly being pulled in???
Kashani
- Why is the ninja... so deadly?
er.. I mean, 669,600,000 MPH, forget the million part.
Light speed is 670.615.200 mph, I believe
eek... I mean 696.6 million. My bad.. I spent the week end in Vegas... still hung over.
- Why is the ninja... so deadly?
If we could harness the energy of Black Holes, that would be one heck of a power plant. Hmmm...somebody A LOT smarter then me will have to figure out the specifics, however, it would be amazing.
That's my 1/50 of $1.00 US
JM
Big Brother is watching, vote Libertarian!!
--Justin Mitchell
"2nd Place is a fancy word for losing" --Bender (Futurama)
Modern Science (or Modem Science, for those of you that like to mispel things) continues to amaze me. They 'know' so much about black holes even though no one has ever touched them. I wonder how much of this is idle conjecture?
this sig limit is too small to put anything good h
some quick calulations....
6,500,000 MPH = 2,905,760 Meters/Sec = 2.9e6
Speed of Light = 299,792,458 Meters/Sec = 3.0e8
if you figure this out, you get the fact that it is only traveling at less then 1% the speed of light (the theoretical limit). now lets see how Relatively stacks up agenst say a 1 kg particle.
m=mo/sqrt(1-(v^2)/(c^2))
This brings the relative Mass to 1.000047 kg or a ~.005% diffrence in mass. No big deal... Havent they goten particals up to 10% the speed of light before in mass accelerators.
How the universe will end is, I think, still an open question.
If the universe is "closed", it will end at some point with a big crunch as everything collapses together due to gravity.
If the universe is "open", it will continue expanding forever.
If I remember correctly, current thinking is that the universe is "open".
Disclaimer: I am not a physicist.
something with that much gravity would have to be orbiting rather fast to stay in orbit.
As a believer in the Heisenberg-Bohr tranquilizing philosophy I can only contest this statement. It was contrived many years ago that black holes were not actually of physical existence but of a pseudo-perceptual existence, one which could only be brought upon by an intellectual being or beings (in this case the so-called 'astronomers' who are making this claim) thinking about seeing this phenomena taking place. However if we allow for an assumption that these so-called 'black holes' really do exist, we can easily put down the statement they've made regarding 'seeing matter being sucked into a black hole', where the 'black hole' they make reference to is claimed to be 'a dense region where extremely strong gravity sucks in everything, including light'. We can do this by applying this basic principle: consolidated holes in Heisenberg antiferromagnets are always drawn towards each other at rather large distances. This goes hand in hand with the Casimir force, which further substantiates my claim, it is caused by the alteration of the quantum zero-point spin wave energy. With the deficiency of a long-range Coulomb repellency among the holes, such an inclination introduces an instability of any charge-ordered state in the dilute doping hindrance. Therefore the 'black hole' of everyday understanding can not 'suck' at more than 6 million mph, or even 3 million mp3.
Nothing can ever suck without some stange act or quantum physics because "sucking" can only occur in a complete vaccume. Ditto about the quantum stuff. Geeze you guys. I know that and I am in high school.
Wouldn't a Blackhole eventually consume all the matter in its galaxy?
Nope. A black hole doesn't have any more mass than the star it originally came from (plus whatever matter has been sucked in).
Now, since stars are roughly spherical in shape, the center of mass is the center of the star, which is where the black hole is now. So once you get as far away from the black hole as the surface of the star was from its center, a black hole's gravitational pull is no stronger than that of the star itself. It's only when you get inside that radius that trouble begins.
Naturally the radius grows as more matter gets sucked into the black hole, but nothing short of an entire planet (and even then we're talking a planet the size of Saturn) is going to change the radius by any significant amount.
No, I'm not a physicist, by the way.
TN^T users know different...
Please, let's not make any Monica Lewinsky jokes here, OK?
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Did you know that black holes have no hair?
A quote worthy of John Archibald Wheeler, If im not mistaken.
Wow. Could this be the "Giant Sucking Sound" that Ross Perot warned us about in '92?
-- Raw --
IIRC, it's pretty much been determined that there is no way to tell one way or the other. Whether the universe will collapse or not is based on the amount of matter in the universe. If it's above a certain point, it will collapse, if it's below that point it will expand forever. The amount of matter in the universe, however, MUST be very close to that amount to the point that we really have no way of measuring it with enough accuracy to tell. If the amount was too far below the point the universe would have expanded far too fast for any planets or anything else to exist. If it were too high above that point it would have collapsed during the initial moments of its existence. In short, we'll just have to wait and see. Not like it matters a heck of a lot, unless something really screwy happens and it collapses in the next 50 years or so.
-matt
WRT the galaxy collisions: IIRC our galaxy is actually on a collision course with another galaxy as we both head towards the great attractor. This is still millions of years in the future, but it's pretty much gonna suck for anything living in either galaxy when it happens. As a side note, last i heard all we knew about the great attractor was that it was something with a whole butt-load of gravity sucking us, and many other things towards it. Anyone know anything else?
-matt
> Since the hole emits the same gravitational attraction in all directions, it should stay in the middle, right?
Nope, straight through the floor.