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Chandra Getting Results
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Truly simple systems... require infinite testing. -- Norman Augustine
Truly simple systems... require infinite testing. -- Norman Augustine
Re:X-Rays... (Score:1)
> blackhole produce an x-ray? and how are x-rays > produced here on earth for imaging
> etc?
Easy! We take really big trash compactors and smush down all those AOL floppies,CDs, and old National Geographics in our basement, stir in some MakeMoneyFast emails and mash 'em down even more until they form eensy-weensy little black holes, then dump gas into them to make X-Rays. In fact, next time you go to the dentist, ask them if you can open up the X-ray machine and play with the black hole inside. (If they offer you a complimentary somewhat-oversized white jacket, politely decline and run like hell!)
Re:X-Rays... (Score:1)
I believe that when gases are compressed down to that level, near the event horizon, the gas gets so hot that high-frequency gamma rays are emitted. Relativity does its thing, and you have x-rays (longer wavelength than gamma) once you get far enough out of the black hole's gravity field.
Now, there's an entirely different kind of radiation that's been theorized, Hawking radiation, which says that even a black hole with no matter flowing into it can emit radiation.
Quantum theory states that matter-antimatter particle pairs are spontaneously bursting into existence from the vacuum, and this happens constantly. Normally they just annihilate each other immediately. But when a particle pair pops into existence too close to the event horizon, one particle may get sucked in before the annihilation, and the other flees into outer space, and so it appears that the black hole is "emitting" particles. This is probably a half-assed way of stating the theory, but you get the point.
Satellite has two L's in it (Score:1)
Welcome to the club, baby, yeah!
Re:This is big (Score:1)
Don't be fooled. This is all a lie. (Score:1)
But now, NASA has it easy. By using digital technology and image processing software, they can generate anything that they want. They can scan a maple leaf or a half-eaten bagel, import it into Photoshop, invert it, switch the palette, and claim that it's a "black hole at the center of the galaxy M87 Virgo A." Hogwash, friends. Hogwash. God is not fooled, and neither am I. There are no black holes. There are no other "galaxies". The same can be said for all other types of deep-space objects. "Quasi-stellar radio sources?" What blatant liberal jargon! These are distractions, friends, distractions. Which brings me to my next point.
The astute reader is now wondering where all of our taxpayer money has gone, if in fact there is no Chandra X-Ray Observatory. The answer, I am sorry to say, is quite disturbing. NASA is nothing more than a front, a pseudo-agency established by liberals in the middle part of the previous century. The liberals wanted to put together something that sounded really expensive. And what sounds more expensive than space travel? What better way to fool millions of people and cheat them out of trillions of their hard-earned dollars?
And so began the Liberal Funding Agency. The money allocated by Congress to NASA is immediately funneled into various left-wing organizations. A sizeable chunk is used to prop up Communist dictators around the world. A large portion goes to fund Planned Parenthood clinics in cities around the nation. The National Organization for Women gets a piece of the action too. Same thing for various homosexual and black groups. The liberals also use this money to attack our children. They buy certain unacceptable books to stock public libraries with. "On the Origin of Species" by Darwin and "A Brief History of Time" by Hawking are among these heretical books. Their top priority is to enslave children; always has been, always will be. And our money is helping them do it.
So what you need to do, friends, is write your congressman and demand that NASA be dissolved immediately. Strike a blow against liberalism and multiculturalism. If we can work together, we can bring these people down once and for all. Thank you for your time.
Re:Is this news? (Score:1)
(I think that the other poster got confused between Kepler and Copernicus regarding the principles 1 and 2. And the models are from Friedmann, I think).
Guy Ouellette
guy.ouellette@ri.cgocable.ca
Re:How does chandra work? (Score:1)
This link might give you some of the info. that you are looking for:
http://xrtpub.harvard.edu/about/hardware.html
A new European Space Agency x-ray telescope has more mirror surface area, but does not have the resolution of Chandra. They are complementary spacecraft.
Re:Is this news? (Score:1)
A black hole do not grow faster than other objects (Score:1)
But so will anything else if something hits them. The earth for example is constantly bombarded with particles from space.
Consider a star with the mass m and radius r.
Then consider a black hole with the same mass.
At the distance r from the center of that black
hole you would feel exactly the same gravitational pull from the black hole as you would feel from the star if you were standing on its surface.
The difference is that the gravitational pull of the black hole keeps increasing if your distance is less than r. This is in contrast to the gravitational pull of the star if you are inside it. (Since you have lots of mass around you pulling at you you can no longer simplify the star as a point formed gravitational source.)
So, you would actually have a harder time getting a black hole to grow as opposed to getting a star to grow since objects can pass closer to the black hole without crashing into them.
(Allright, some inaccuracies in this post, a star does not have a surface you can stand on, and it also loses mass by emitting energy, etc, but that isn't the point of the post)
Re:about dark matter (Score:1)
but if matter tended to group together that much you'd expect larger stars to be more common than smaller stars.
Well that may be the case, however the bigger a star is the faster and hotter it burns its nuclear fuel and hence the shorter its life. Therefore there may actually have be more high mass stars in total over time, but at any one time there is going to be more of the stable long lived low mass stars.
Re:X-rays can beat black hole gravity? (Score:1)
-l
Re:about dark matter (Score:1)
Hmm... I just read an article in yesterday's paper about Chandra discovering a whole new swath of black holes. Here's the Yahoo bit. They're all under News Stories and notice how they're all in the last three days. Yahoo links. [yahoo.com]
That's really neat that this
Droit devant soi on ne peut pas aller bien loin...
Re:14 Billion Light Years (Score:1)
Erm, I don't know about you, but I find Heisenberg's Uncertainty Principle a much better explanation for why the known universe is lumpy. If it had been totally smooth while in the singularity, we'd have known the positions and velocities of everything! As it is, there were irregularities in the singularity which are also expressed as lumpiness now.
Another theory for why the Universe is lumpy is that there could be different parts of the Universe, some lumpy, some smooth, some curly, some I don't know what. But lumpy is what we needed to get where we are, so the Universe is lumpy so we can observe that it's lumpy.
Ahh, circular reasoning at its best.
Droit devant soi on ne peut pas aller bien loin...
Re:Is this news? (Score:1)
If this is the case, then how come it's still here?
I mean shouldn't it exist as the surface of a sphere making up the expanding boundary" of the universe?
I hope this helps. The universe is expanding in all directions with respect to all points. What I mean is:
1- the Universe looks pretty much the same no matter where you look and,
2- the Universe looks pretty much the same no matter where you look from.
These two observations, also known as Keppler's laws, mean that there is no detectable center of expansion. The cosmic background radiation (CBR) looks like it's coming from everywhere, and somebody else somewhere else would think some of it came from us.
So, in three dimensions, the Universe has no boundary. The fact that you're imagining it as a sphere means you're confused. One of the Keppler models does imply a spherical Universe... but in 4 dimensions. Just in case you're curious, the other two Keppler models imply a saddle-shaped and a disk-shaped universe (in space time).
Droit devant soi on ne peut pas aller bien loin...
Re:Is this news? (Score:1)
No, the universe was expanding at such a rate at the Big Bang that the light getting to us from then has been red-shifted down to the microwave zone. It is not dissipation, it is red-shifting.
Droit devant soi on ne peut pas aller bien loin...
Re:14 Billion Light Years (Score:1)
"We can observe that two regions of space which are not causally connected (ie a light signal cannot have travelled from one object to the other within the age of the universe) abide by the same laws of physics without there being any real reason why they should."
The fact that there CAN be two regions of space that are not causally connected lends support to "Inflation" correct?
I have always had a problem grasping that conjecture in the Big Bang theory. It is like we get to suspend the light speed limit for a few time factors of 10 just to make observations fit better.
If you have any more insight to this phenomena I would like to hear it.
Re:about dark matter (Score:1)
Re:This is big (Score:1)
Dark matter is a bit more local observation - by looking at the rotation speed and mass distribution of OUR OWN galaxy, we can conclude that most of its mass is not visible as stars. So it is not directly related to observing far away galaxies. - But it affects our estimate of the average density of matter in the universe.
These new galaxies were not visible because x-rays dissipate less over distance. New gamma ray observatory (GLAST [stanford.edu]) will see even more distant objects.
Re:about dark matter (Score:1)
Re:about dark matter (Score:1)
Dang.. (Score:1)
Re:That's Hawkings radiation (Score:1)
Err, not to be picky or something - it IS the accretion disk.. Very hot plasma around the black hole (but Above horison of course - in fact the closest part of the disk is (should be) about three times the radius of the horizon - depending on the rotation of the black hole)
One number that is very surprising - the matter falling into black hole can convert almost half of its rest mass into energy to radiate! Much more effective than fusion can be.
Re:So, are virtual (anti)paricle pairs "the aether (Score:1)
With all due respect to Dr.Hawking - it is far from being his idea.
From what I remember from "Physics of vacuum" course I took 8 years ago, there is a rather fancy way to avoid violating relativity dealing with this "sea" of particle. Until MathML is standartised, I can not quote relevant fromulas here
Re:3 Questions (Score:1)
2.) Once a wavelength gets altered in its journey, how can you tell that it was ever a different wavelength?
3.) My own amateur and thoroughly unresearched thought on the age of the universe is that the universe is spacially infinite (and not in a mobius strip sense). There may have been a big bang that caused our own neck of the woods, but I think that you could fly right out of our "universe" and into the next one without even realizing it (except that everything would suddenly be moving apart at a different speed than we are accustomed to). My logic behind this is:
a.) If you accept that the light we are seeing from distant galaxies is x years old with a direct correlation to the speed of light in a vacuum, then it makes sense that if we just look past those galaxies we'll see farther and farther into the past, right? And somewhere farther in the past is the Big Bang. Have we just not built a powerful enough telescope to see the Big Bang yet? Even if you agree with some arguments saying that the universe expanded much faster than the speed of light, the light given off from it would tend to travel... at about the speed of light, right? So we may never see the light on the leading edge of the BB, but we'd HAVE to see the light from the trailing edge at some time... if the Big Bang expanded at more than three times the speed of light, then perhaps the light from the trailing edge is still traveling at twice the speed of light away from us?!? Light traveling faster than the speed of light has to throw a wrench into someone's equation.
Again, thanks.
Re:Getting transcendental! (Score:1)
3 Questions (Score:1)
2.) X-rays are just another wavelength on the electromagnetic spectrum, right? What says that a wavelength can't get changed in the course of its travels across the universe? Passing through nebulae, slipping around black holes, etc. seems like a wavelength would change fairly often from light year to light year, right? What makes us so sure that the x-rays CHANDRA is imaging are pristine, untampered, reliable wavelengths? Is there no method of turning a microwave into an x-ray, and vice versa, or even degrading the wavelength into the visible spectrum (and back)?
3.) If we really are seeing 14 billion years into the past, and this represents something close to the beginning of the universe, why are we seeing galaxies? The big bang isn't reported to have exploded into tidy little galaxies. Why aren't we seeing large, hazy globs or strings, or something? If we are seeing galaxies (or whatever being viewable as bounded pinpoints), then doesn't that imply that the universe is vastly older than the oldest images we have yet seen?
Thanks.
Near IR, Far IR, Submillimetre, Microwave (Score:1)
Leaving aside the fact that there is a _huge_ distance between an average-frequency IR photon and an average-frequency microwave photon, there is another band in between the two, called "submillimetre" in the references I use.
The reason the article's observations on x-rays are important is that, while we knew that there were substantial quantities of x-rays being emitted from most directions in the universe, we didn't know where they were being emitted from (just that it was roughly uniform). The telescope had a much higher angular resolution than anything else we can look at the x-ray background with; it discovered that most of the x-rays were being emitted from tight regions in the same place as galaxies that we've seen using other telescopes. Thus, most of the x-rays are probably coming from galactic cores.
Re:Daily Astronomer (Score:1)
We really need a SlashBox(tm) for this one.
Re:Don't be fooled. This is all a lie. (Score:1)
john grimes, Chandra Science Mission Planner
Re:3 Questions (Score:1)
1) The universe is expanding.
Think about a pool of water. your thinking that if I cause a circular wave to start in the pool we have a center of that wave. But thats not what is happening. More equivalently would be that the whole pool grew. And to make in even more equivalent the pool which I am comparing to a universe is not in ground.
So at the beginning there was one point. Now that one point has grown to all points, so all points are that center point, as there is no center.
Does this help?
2) in a way you can't tell directly it was at a different wavelength. What you generally do is take a spectra of an object (lets say galaxy). The spectra tells me how many photons it is emitting at a certain wavelength. Now we know that most matter is hydrogen (can tell from the local universe) and we know the atomic transitions of hydrogen and at what wavelengths (on Earth) hydrogen gives off a lot of light. So basically we will compare the local galaxy (and our knowledge of atomic physics) to that far off galaxy and compare the shifts in wavelength. This is very, very reliable. Good question.
3) I don't want to touch this. Not because its all wrong, but because its my poor explanations skills will only confuse you more. Read more
John Grimes
Chandra Science Mission Planner
Re:How does chandra work? (Score:1)
specifically http://chandra.harvard.edu/about/telescope_system
john grimes
chandra science mission planner
Re:How did they calculated... (Score:1)
distance=time*velocity+.5*time^2*acceleration
Now this equation is very wrong in that its newtonian mechanics not GR but the GR equation is no where near as simple. But Hubble's comstant is basically your velocity term and then we have an accleration term (that recent evidence suggests is not sero) and then
Its a complicated equation that depends of constants that we only have very rough guesses for.
john grimes
chandra science mission planner
Re:bullshit article (Score:1)
john grimes
chandra science mission planner
Re:X-Rays... (Score:1)
[tiac.net]
www.tiac.net/users/shansen/belljar/xray.htm
The paragraph towards the end is the relevant bit
Re:Or turn it around... (Score:1)
~~~~~~~~~
auntfloyd
Re:14 Billion Light Years (Score:1)
The space-worthy DC-10s (which are modern aircraft)?
The evil overlord Xenu?
The $100,000 'treatments'?
You're not going to tell me that a 'religion' founded by a hack sci-fi writer based on spaceships and alien psychologists is fake, are you?
Geez, not even L. Ron's *cult* is imaginative. No wonder he was such a failure.
~~~~~~~~~
auntfloyd
Re:What noone has said - Congratulations! (Score:1)
To focus X-rays, one can either find a material that refracts X-rays so that lenses can be built, a material that reflects X-rays so that a reflecting telescope can be built, or find an alternative focusing technique.
X-ray lenses can be built, but the mass of metal required to bend X-rays to a respectable focal length may be too great for a satellite. X-ray mirrors may not be possible. I don't know what they actually use in the satellite, but I think they use an array of mirrors that reflect X-rays in a glancing manner, such that the incoming X-rays are almost parallel to the mirror.
It is interesting to note that the compound eyes of insects focus light in the same manner. Therefore, if the engineers wanted to make another X-ray telescope, they should consult entomologists and study the structures in insect eyes so that the next generation of X-ray telescopes may copy the design principles of insect eyes.
Re:about dark matter - it's simple (Score:1)
Re:Hemos is such an idiot (Score:1)
Re:X-Rays... (Score:1)
Color TV is 25,000 volts IIRC.
B&W TV is about 17,000 or 18,000 volts.
The X-Radiation is rather weak, almost negligible for B&W, but strong enough on color that you do not want to be right on top of it.
You bit (Score:1)
Re:Don't be fooled. This is all a lie. (Score:1)
Re:Don't be fooled. This is all a lie. (Score:1)
Wow, You mean I'm getting paid decent money
to maintain the networks for a Control Center that
doesn't do ANYTHING. You mean I watched a FAKE
satilite drift from a FAKE shuttle as it was
supposed to be happening?
Thanks, you opened my eyes!
Re:X-rays can beat black hole gravity? (Score:1)
Re:Black Holes (Score:1)
Re:X-Rays... (Score:1)
How did they calculated... (Score:1)
Moderate this down (-1, Dot Your "r"s, Cross Your "h"s)
--
Re:Dark matter as "optical molasses"? (Score:1)
Actually, that's one of the methods for detecting dark matter and/or black holes. Astronomers lookd for instances of gravitational "lensing," where a very massive object has distorted the light from a distant star. By measuring the distortion we can get an idea of the mass of the object causing the lensing.
Re:Too big to evaporate (Score:1)
Re:Is this news? (Score:1)
But maybe you can clear up something that bugs me about the whole "background radiation" thing.
If it's radiation left over from the big bang, then
didn't it radiate in all directions from the center of the universe at the time of the big bang?
If this is the case, then how come it's still here?
I mean shouldn't it exist as the surface of a sphere making up the expanding "boundary" of the universe?
This question never occurred to me when I was in physics class but it seems to make sense.
Where is the flaw?
---CONFLICT!!---
Or turn it around... (Score:1)
Now comes the bottom line: how insignificant am I, a human, in a cosmic scale? ...
Let's say that intelligence is truly unique in the Universe, and we are the only examples. That means even the lowliest human being is unique on a cosmic scale. After all, after you've seen the couple dozen or so star types, you've seen them all. But there's only one place in the Universe you'll find intelligence.
---
I think the BH may actually decrease in size (Score:1)
I don't know if this includes everything that gets sucked into the black hole, but it may very well since classic physics gets unclassical as matter accelerates to near c (speed of light).
For instance, using LaGrange equasions as v->c, the length/size of an object approaches infinity, time change approaches 0, etc. with respect to a stationary observer. This means a blach hole has infinite timeless mass? While I doubt that, there are other cleve ways of explaining what could happen.
Re:Getting transcendental! (Score:1)
Regardless, it is stuff that I like to think about which makes my head spin!
This should be front page news!! (Score:1)
This is what bothers me the most about coverage of the space program. Most people can't name 3 astronauts that where on the latest shuttle mision, but they can name the last 3 failures. I think it is because it is easier to understand, and report, a satelite crashing into a planet than it is to understand a discovery such as this.
Re:This should be front page news!! (Score:1)
Re:More Chandra Accomplishments (Score:1)
If you ask me, ALL Black Holes are cool. ;-)
Re:X-Rays... (Score:1)
The X-ray emissions of a CRT can be increased to hazardous levels in some cases simply by tweaking the high voltage to out-of-rating levels. Overdriving some color monitors can do this as well. You don't notice anything right away, because cataracts are long term eye damage.
Re:Is this news? (Score:1)
No, the EM radiation is infrared, not X-ray. Energy from the Big Bang has dissipated so much that infrared is the only thing left of it. Any radiation with higher frequency (eg. X-rays here) must certainly come from objects like stars, quasars, black holes, and the like. This does not affect the Big Bang theory at all.
There's a good website about this on... (Score:1)
X-rays can beat black hole gravity? (Score:1)
Even light gets sucked in by black holes, yet X-rays can get out? Does anyone know anything about this? I'm somewhat skeptical, but since i know nothing about the subject, any knowlege would be appreciated.
Re:Is this news? (Score:1)
Re:X-Rays... (Score:1)
If you can't figure out how to mail me, don't.
Re:More Chandra Accomplishments (Score:1)
Being an undersexed geek, I would have to agree, and state that most pink holes are cool too. :)
If you can't figure out how to mail me, don't.
Well that's very cool! (Score:1)
I've always been an armchair theoretical physicist, and I think this is fascinating. But what does this do to the 3 degrees above zero theory that said the background radiation was a residue of the big bang? Sure doesn't sound like it now...
So what does this do to the "big bang" theory?
If you can't figure out how to mail me, don't.
Getting transcendental! (Score:2)
Second, I'd like everyone to extend their imagination. The article talks about 70 million röntgen radiation (x-ray for the US) sources. That's like a lot. I mean, if you start thinking how big the universe is, it's just mindboggling. There are, as we all know, to quote Carl Sagan, "billions and billions" of stars.
And to think that what we are seeing right now is something which in actuality happened many thousands if not millions of years ago. That is, that EM radiation has travelled for a long time in space before we finally managed to observe it.
So the universe is BIG. Now bear with me for a second. Of the stupendous vastness of space and the multitude of stars, we know for certain that life exists on only one planet, the Earth. Therefore we think Earth is special. Well, it is. After all, it is our home. But Earth is just one out of many billions of objects in the universe. It's utterly and completely insignificant on a cosmic scale.
And if you zoom in to this planet, you'll find a lifeform, a human being. One human is insignificant to this whole planet. Hell, one human is insignificant to the country s/he lives in.
Now comes the bottom line: how insignificant am I, a human, in a cosmic scale?
This thought was a big "wow" to me. I'm insignificant! I'm a nano-scale microbe on a universal scale, and that feels wonderful!
Re:Is this news? (Score:2)
Maybe I don't understand something about /. moderation, but the above poster is absolutely correct, the people talking about the result taking a chunk out of big bang theory are making a catagoreical error; certainly doesn't deserve a score of 0. Why the hell do some people just HAVE to comment on something regardless of the fact that they know they don't know what they are talking about?
The article wasn't moderated -- all anonymous articles start with the score 0, as opposed to normal users. Moderators later can moderate anonymous articles up, but this one was just posted, so it remained with its initial score.
Hollywood Conspiracy! (Score:2)
Of course, everyone knows this is hogwash. Black holes are black, period. That's why they're called black holes and not multicolour rainbow holes!
This post is part of a larger conspiracy originated by Hollywood more than 20 years ago. You may remember a rather cheesy movie called "The Black Hole" that came out in 1979. Well, it seems clear this whole theory was created simply for sensationalization purposes. After all, who wants to watch a movie about a black hole in space that no one can see. Pretty boring stuff!
Of course, since then more and more movies and television shows took advantage of neat hole-in-space special effects, so it was obviously in their best interest to support this campaign of disinformation.
Fight the conspiracy!
(uh oh, I think I'm starting to sound like "The Conspiracy Guy" on Space!)
Re:Is this news? (Score:2)
I think the issue here is that a post based on misinformation has been moderated upward twice as "Informative" while a post providing correct information languishes at zero. The facts here shouldn't be controversial: even if the Big Bang Theory is a Big Bust, or even if the cosmic background radiation is a measurement error (doubtful, but for the sake of argument let's say it is), such radiation is in the microwave region, not X-ray. So this new discovery has nothing to do with the background radiation claims of the Big Bang Theory.
I don't want to be hard on the original poster-- many is the time that I've had this kind of an "Aha!," then further information shows me to be embarrassingly mistaken. And I'm sure the two moderators made exactly the same mistake the poster did. This happens all the time on Slashdot where something seems insightful/interesting/informative at first glance and gets moderated up (moderators are busy people, after all), with a correcting post coming some time later when there is so much else competing for moderators' attention that the correction lays untouched at 0 or 1.
Even though this offends my sense of justice a bit--misinformation getting marked as "informative" isn't one of moderation's finest hours--moderation works well enough that cases like this only call for its imporvement, not its abolition.
As for whether the original article being "news:" Hell, yes! The cosmos proves more wondrously strange each time we expand the "eyes" and "ears" we use to examine it. There is a good chance that there will be far more questions than answers generated in astrophysics during our lifetimes, given the new technologies we'll be able to point "out there," but that makes it all the more interesting and inspiring.
Re:about dark matter (Score:2)
First Haiku (humor, not troll) (Score:2)
Shouldn't one be taking care
of one's own wallet?
Re:This is big (Score:2)
This is light above the hole (Score:2)
NASA would use the GIMP! (Score:2)
himi
Anti-religous? (was: Re:14 Billion Light Years) (Score:2)
I realize that the scientologists have tried very hard to burn their bridges with the rest of the world (e.g. suing anyone that publishes negative info about them), but we should rise above their level and treat this message objectively. It's not flame-bait, it's a statement of opinion. I can see it neever going up any, as there wasn't much in the way of useful info, but it's not a first-post, and it was on-topic, so just leave it alone.
Would someone with some moderator points push the post back up to a 0, please (underrated would be fine).
14 Billion Light Years (Score:2)
Personally I'd be prepared to believe the latter. There seems to be a basic assumption that the entire universe must have been contained in the big bang, just becasue space is expanding outward as a result. How does this follow, exactly? Could the "force" of the big bang not be simply expanding a small section of the universe outward? In fact, the influence of surrounding matter would certainly be a good explanation for why the known universe is "lumpy".
I do agree that the matter in "our neck of the woods" would almost certainly all have come from the initial singularity, but why does that say anything about what is at the edge of the big bang propagation?
Then of course, I start wondering: does this mean that somewhere there's another big-bang like event that is speeding toward us at the speed of light? Will I feel it?
Re:14 Billion Light Years (Score:2)
Ok, so you made the point that:
1) My karma went up 2 points for this: no it didn't I start at a 2.
2) My weak grasp of physics made me leap to the silly conclusion that space/time could "expand into" something outside of it: nope agian. I am simply putting forth a question, but let's phrase it like this instead. If a singularity at the heart of a largish galaxy were to "explode" (actually I think I remember hearing a theory that this could happen if some massive gravitational force "smeared" the black hole out enough that part of it passed its own event horizon: was that Hawking?) what would we see? I think we would see something very much like a miniature version of our universe's big bang. We would see an area of space-time "expand" outward in the form of a catalysmic explosion and from inside that explosion there would be a beginning of time and a boundary to space that matched the orginal singularity's explosion.
Someone else said that their pet theory for why space is lumpy was the UP. I find this to be a circular answer, as the UP is an artifact of the complexity of our universe. Thus, the question remains: why is our universe complex? Why is everything not ordered in perfect symetry? Was it the hand of some capricious god or is there a force outside of our singularity-borne frame of reference. If there is a force outside of this frame of reference, does it interact with ours in the same way that our region of space would interact with the results of the above explosion? Could we, perhaps detect some trace of that outside?
As to my having the mathematical background to understand graduate-level physics/cosmology texts: no, I don't and I don't really think that should be relavent. In reading some of all and all of some of the sources that you cite for "amatures", I have come across this assumption time after time, and yet no one has ever stooped to explaining why. If the pros are to educate the masses (as I, for example, seek to educate others in the use of computers) simple assumptions must be clarified and explained.
I would, for example, never suggest that in order to question the assumptions of programming languages, a layman should read and understand Knuth's Art of Programming. It often takes a non-computer scientist (like Larry Wall, creator of Perl and a linguist by training) to question assumptions and come up with "the wrong answer". Often that wrong answer is, in fact, wrong. However if you cannot answer without re-stating the assumption (e.g. programming languages should not be context sensitive), you have a problem.
Thank you for the clarification on the current age theories. Last I heard there was a debate that set the lower limit at 9-point-something billion, but it certainly was a while ago, and I appreciate the update.
Re:14 Billion Light Years (Score:2)
This is circular. The uncertainty priciple is the result of a complex universe. Why is it complex? Why not an ordered smear of energy that could never result in... well, us; stars; galaxies; etc. What force acted upon the early universe to cause such a dramatic non-uniformity?
Too big to evaporate (Score:2)
In contrast, any black hole we observe from earth will have a stellar mass and will *not* evaporate. At least, not until long after the last star has reached thermal equalibrium with the rest of the universe.
Re:Is this news? (Score:2)
I doubt it has much influence on the big bang theory, but it is worth mentioning that there are a few reputable scientists which have doubts about the big bang.
The conspiracy theorists love to point out how the Vatican commishioned a priest who knew some physics to reinvolve the church in the discussions of the origin of the universe, then this guy descided that the idea that pushing something like the big bang on the scientific community would be the best way to do that. This guy ran arround to various scientists tring to push the idea and got noware untill people noticed the universe was expanding, then people started beliving him. (Note: You should not take this story as an argument against the big bang, but as a warning about how religious people follow there biases)
It is a good test of your understanding of the scientific method to think about exactly why the expansion of the universe provides evidence for the big bang. Example: if we lived in a cluster of galixies which had an eliptical orbit arround soemthing really big then it might appear that al the galaxies were moving appart. It's fun to think about what exactly is wrong with this alternative explination.
Jeff
Daily Astronomer (Score:2)
For the amateur astronomer or just the astro-curious, this NASA site ( http://antwrp.gsfc.nasa.gov/apod/astropix.html ) presents a different photo every day with explanation and reference links. This needs to be in your list of "sites to start the day with".
Dark matter as "optical molasses"? (Score:2)
I seem to remember an article [slashdot.org] on Slashdot about light slowing down as it passes through a Bose-Einstein condensate. Has anyone considered that the "dark matter" out there might also be transparent but dense, such that it slows down light in a similar manner?
We're talking about delaying light for about 2-5 billion years in order to make the math come out right. The researcher in that article thinks she can get it down to 120 feet per hour. If the light from our distant galaxies had to go through a couple lightyears of this goop before it reached us, that would account for the differences.
Yeah, it's easier just to say that there was stuff here before the big bang. But where, then, did it come from? And did it have a hand in creating the big bang?
Re:Dark matter as "optical molasses"? (Score:2)
New Ways to See Black Holes
http://www.npr.org/news/
We are living in fantastic times. I remember when I use to watch astronomy programs on PBS in LA in the late 70s(anyone else remember Krupp(sp?) from Griffith Observatory?) that all the important stuff was discoverd at the turn of the century with Einstein.
Man was I wrong.
Confirmation of extrasolar planets. We may be able to determine the atmosphere on some in the not too distant future!
Confirmation of black holes. I remember when they were just crazy scifi objects - fun to talk about, but you didn't really believe something so outside of human experience could exist. The book mentioned below is in many ways a history of people trying to come to terms with a concept so alien to our common sense notions of space and time.
Possible ocean on Europa...and life? In progress.
"Black Holes and Time Warps" by Kip Thorne is a great lay introduction to subject and its history. He is one of the authors of one of the classic texts on gravitation. I skipped the book for a long time because of its title - it sounded like other 'wacko' science books. It turned out to be a joy to read.
http://www.amazon.com/exec/obidos/ASIN/03933127
Todd Stewart
Software Engineer
3DO
Re:14 Billion Light Years (Score:2)
What fascinated me even more was that they thought the heavy X-ray emissions might be coming from black holes
My thought is that we might be near one of the "rims" of the universe and have been moving away from these point-sources ever since the beginning of the universe which may be expanding in certain regions faster than others. In this case, the X-rays have simply been following us and finally caught up
Re:about dark matter (Score:2)
One of the strongest pieces of evidence in support of the Big Bang theory is the very good match between the abundance of light elements (hydrogen, deuterium, helium, lithium and beryllium) predicted by the BB, and actually observed by us. The BB theory places some limits on the amount of the "critical mass density" of the universe which can be made up of ordinary baryonic matter. That limit is much less than 1.0, closer to about 0.1. What that means is that _if_ the BB is correct, and _if_ the universe contains the critical mass density, _then_ most of that mass density must be non-baryonic matter.
Now, baryonic matter is good old protons, electrons, and neutrons: we and most of what we can see in the current universe (stars, planets, galaxies, etc.) are made of baryons. The galaxies just discovered by Chandra are undoubtedly made of stars (baryonic). Black holes are made of baryons, under most scenarios in the literature. MACHOs are just low-mass stars or high-mass planets, and they, too, are baryons.
So what the heck _isn't_ baryonic? Well, neutrinos aren't. There was a hope about twenty years ago that most of the mass of the universe might consist of neutrinos -- but recent experiments indicate weakly that the neutrino mass is too small to do the job. A universe of neutrinos would also lead to large-scale structure of galaxies and galaxy clusters very different than that which we observe. So, neutrinos are probably out. That leaves exotic stuff: wierd particles called "axions" or "WIMPs", or "strange matter"; all of these are theoretical, not experimentally confirmed (as far as I know)
In short, _if_ the density of the universe is even close to the critical density, it means that a) some exotic sort of matter dominates or b) the current theory of BB nucleosynthesis is wrong.
Re:14 Billion Light Years (Score:2)
not really. Objects are still moving away from each other at sublight speeds. It's just that the space _between_ them is expanding really, really fast during the inflation period, so the net result is that they get too far apart to be causally connected. Yes, it makes observations fit better, but we stay within the rules at all times.
I would encourage you to e-mail me if you want more information.
More Chandra Accomplishments (Score:2)
Here's a link [yahoo.com] to another story about another one of Chandra's accomplishments: finding "the coolest black hole ever detected".
How does chandra work? (Score:2)
How does chandra work? How are X-rays focused? Pinhole camera? I doubt that because it would really cut down on light gathering.
Re:X-Rays... (Score:2)
X-rays are produced here by accelerating electrons to very high speed and smashing them against a target. Kinda like a miniature acelerator, I think. That's why televisions create x-rays, because the tube is essentially a low-energy particle accelerator, smashing the electrons against the phosphor of the screen and making them glow.
I'm not one hundred percent sure of how the black holes create them, but I think it has something to do with the kinetic energy of the electrons as they fall over the event horizon... someone feel free to correct me.
If you can't figure out how to mail me, don't.
Black Holes (Score:2)
George W. Bush- "Not a crackhead since 1974!"
What noone has said - Congratulations! (Score:2)
Re:X-rays can beat black hole gravity? (Score:3)
Re:Black Holes (Score:3)
This is big (Score:3)
Also I wonder how much closer this will put us toward making the universe a closed system?
Also the age of the universe is calculated finding the oldest light we can. This makes it sound like there may be much older things out there not giving off any light.
Re:14 Billion Light Years (Score:3)
You're more prepared to believe that there is matter in the universe that pre-dates the big bang than that we've got the age of the Universe slightly wrong? So we've got matter existing "before" the creation of space, time, and even the higgs scalar background necessary for "mass" to exist? Not only that but it surviving the singularity at t=0 ?
Anyway, moot point, last time I checked mosts people seemed to think the Universe was 12-15 billion years old +/- 10% ish, and the 14 billion figure in the article has probably got a pretty hefty error range on it itself. So it's perfectly possible that these were created after t=0.
Your grasp of elementary cosmology it fundametally flawed as you are attempting to apply traditional Newtonian/classical physics to the creation and expansion of the Universe. In your second paragraph you twice refer to space expanding outwards, this dosn't really make any more sense than the idea of events "before" the big bang, just as there was no time "before" the big bang for events to occur in, there is no "space" outside the universe for objects to exist in or for space to expand into. Modern physics, whether classical, quantum or relativistic, cannot be applied to to events outside the universe.
Your third paragraph almost touches on a valid physical point. We can observe that two regions of space which are not causally connected (ie a light signal cannot have travelled from one object to the other within the age of the universe) abide by the same laws of physics without there being any real reason why they should (major oversimplification, but that's a key point) and this is a topic of debate and research within the physics community.
If you've got very good (graduate level or better) physics and maths, plus good astronomy (at least one college course with "cosmology" or "extra-galactic" in the title) then try Principles of Physical Cosmology by Peebles, if not then wade through the last 10 years back catalouge of New Scientist, Scientific American, and Astronomy, and buy a copy of A Brief History of Time.
Re:Is this news? (Score:3)
I'm not an astronomer; anyone know what the ramifications this has on the Big Bang theory? My guess is that it doesn't disprove it. But it sure takes a big chunk out of it...
Ryan Kirk
rkirk@calpoly.edu
http://topflight.net
Precursors to Quasars (Score:4)
It is thought that quasars are early versions of galaxies where the formation gasses are being pulled into a central black hole ( billions of solar masses ) and shining tons of light. Then after awhile an equilibrium sets in and eventually spirals and other older type galaxys form. I often wondered what could have kicked this off.
This seems to be the answer. One of the things Hawkings theorized was that there could be primordal black holes created during the big bang. It is possible that trillions of these things existed and as such started the initial imbalance required to create structure as we see now in the visible part of our universe.
These objects are said in the article to be the oldest things ever observed. I would say just younger than the 2.7 degree kelvin background radiation marking the time when the universe was opaque.
These smaller primordal blackholes would collide and create the gravitational engines that galaxies would form around. Initially, they would suck in gas and burn like a quasar then eventually settle down and become boring old spirals like ours.
As things were far more compact at this time most of the primordals would be gone, but a few may have "slingshoted" from near misses and be cruising near light speed through the universe right now.
And you though a big astroid would be bad!
about dark matter (Score:4)
IMVHO, the "dark matter" is mostly a bunch of sub-stars like Jupiter (these are known as the Massive Astrophysical Compact Halo Objects, or MACHO, a term which covers all big dark matter, like black holes and brown dwarfs), which would have to be about a hundred times more common than stars to explain it. I believe in small MACHOs because small stars are much more common than large stars; a lot of people like to believe that black holes are common, but if matter tended to group together that much you'd expect larger stars to be more common than smaller stars.
That's Hawkings radiation (Score:4)
Hawkings radiation is interesting for a different reason. Some people had observed that black holes physics have a lot of similaries with thermodynamics. The mass of the black hole corresponds to entrophy, iirc. However there was some minor point where the behaviors differed, and Hawkings decided to explore the "impossible" case where black holes really did match thermodynamics. He eventually identified the quantum tunneling mechanism and all hell broke loose in the physics community. Hawkings radiation is now a classic example of a situation where important discovery was made by exploring something that first appears to be a mere coincidence.
As others have pointed out, the X-rays we're talking about here are due matter falling into the accretion disk.
Re:Well that's very cool! (Score:4)
People seem to be misunderstanding the significance of this discovery. For almost 40 years, we've known about an "x-ray glow" with no apparent source that was scattered all over the sky. With Chandra, astronomers have been able to resolve discrete sources for the x-rays, so we now know exactly where they're coming from. I don't think the x-ray glow was ever as uniform as the background microwave radiation, which is identical in all directions with no apparent source.
Re:X-rays can beat black hole gravity? (Score:4)