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Gravitational Waves
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2 Re: Gravitational Waves 2/11/2016, 1:19 pm
boards of FL
Amazingly, this discovery will now allow us to look back in time beyond the cosmic background microwave radiation leftover from the big bang. We will now be able to look back in time and observe the universe as it existed over 13 billion years prior to when god even created it.
Simply amazing.
Simply amazing.
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3 Re: Gravitational Waves 2/11/2016, 1:55 pm
Guest
Guest
It's also going to allow us to "see" in much greater detail the mass and orbits... even what is hidden from our current spectrum. There might be implications for space travel and engines too. The next decade and more will be full of advents.
4 Re: Gravitational Waves 2/11/2016, 7:17 pm
Hospital Bob
boards of FL wrote:
Simply amazing.
What's even more amazing is seeing bds and Pkr speaking with one mind and not at war with each other. I think after seeing this I have hope for the sunnis and shias.
5 Re: Gravitational Waves 2/12/2016, 3:30 pm
boards of FL
Bob wrote:boards of FL wrote:
Simply amazing.
What's even more amazing is seeing bds and Pkr speaking with one mind and not at war with each other. I think after seeing this I have hope for the sunnis and shias.
Not quite. Some people simply don't have a sarcasm detector.
PkrBum isn't capable of "agreeing" with someone on a subject like gravitational waves any more than a kindergartner is capable of "agreeing" that the derivative of 2x^2 with respect to x is 4x.
One necessarily has to possess some level of knowledge of the underlying subject matter in order to truly agree.
My original post was a sarcastic jab at the religous.
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6 Re: Gravitational Waves 2/12/2016, 4:30 pm
Guest
Guest
Then you'll be very surprised in the years to come. This detection came about as they are slowly dialing the device up. At first they thght it was part of the test on the lasers and alignment. It can go to much higher sensitivity... and will over the next five years. Then it will hopefully be setup in space and then the possibilities for it's discoveries and uses will take off. It will likely change humankind... like several other einstein theories already have.
7 Re: Gravitational Waves 2/12/2016, 5:42 pm
boards of FL
Yes, I'm aware of gravitational waves, how they're detected, what they imply, etc. etc.
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8 Re: Gravitational Waves 2/12/2016, 10:12 pm
Hospital Bob
I think it's probably a given that some alien intelligence has learned how to make use of gravity for propulsion.
I say that because a great many UFO sightings reveal objects which can seemingly defy gravity.
I say that because a great many UFO sightings reveal objects which can seemingly defy gravity.
9 Re: Gravitational Waves 2/12/2016, 10:15 pm
Hospital Bob
For over two decades, from 1948 to 1969, Dr. J. Allen Hynek was a consultant in astronomy to the United States Air Force. The subject of his advice, however, was not the fledgling space program or even the moon and stars above, but Unidentified Flying Objects. In 1973 he founded the Center for UFO Studies (CUFOS) and had serves as Director and editor of its journal, "International UFO Reporter."
STACY: Dr. Hynek, as a scientist, you go back as far with UFO phenomenon as probably anyone alive today. Exactly how did that relationship begin?
HYNEK: That's an easy story to tell. In the spring of 1948, I was teaching astronomy at Ohio State University, in Columbus. One day thee men, and they weren't dressed in black, came over to see me from Wright Patterson Air Force Base in nearby Dayton. They started out by talking about the weather, as I remember, and this and that, and then finally one of them asked me what I thought about flying saucers. I told them I thought they were a lot of junk and nonsense and that seemed to please them, so they got down to business. They said they needed some astronomical consultation because it was their job to find out what these flying saucer stories were all about.
Some were meteors, they thought, others stars and so on, so they could use an astronomer. What the hell, I said, it sounded like fun and besides, I would be getting a top secret security clearance out of it, too. At that time, it was called Project Sign, and some of the personnel at least were taking the problem quite seriously. At the same time a big split was occurring in the Air Force between two schools of thought. The serious school prepared an estimation of the situation which they sent to General Vandenburg, but the other side eventually won out and the serious ones were shipped off to other places. The negatives won the day, in other words.
My own investigations for Project Sign added to that, too, I think, because I was quite negative in most of my evaluations. I stretched far to give something a natural explanation, sometimes when it may not have really had it. I remember one case from Snake River Canyon, I think it was, where a man and his two sons saw a metallic object come swirling down the canyon which caused the top of the trees to sway. In my attempt to find a natural explanation for it, I said that it was some sort of atmospheric eddy. Of course, I had never seen an eddy like that and had no real reason to believe that one even existed. But I was so anxious to find a natural explanation because I was convinced that it had to have one that, naturally, I did in fact, it wasn't until quite some time had passed that I began to change my mind.
STACY: Was there ever any direct pressure applied by the Air Force itself for you to come up with a conventional explanation to these phenomena?
HYNEK: There was an implied pressure, yes, very definitely.
STACY: In other words, you found yourself caught, like most of us, in a situation of trying to please your boss?
HYNEK: Yes, you might as well put it that way, although at the same time I wasn't going against my scientific precepts. As an astronomer and physicist, I simply felt a priori that everything had to have a natural explanation in this world. There were no ifs, and or buts about it. The ones I couldn't solve, I thought if we just tried harder, had a really proper investigation, that we probably would find as answer for. My batting average was about 80 per cent and I figured that anytime you were hitting that high, you were doing pretty good. That left about 20 per cent unsolved for me, but only about three or four per cent for the Air Force, because they used statistics in a way I would never have allowed for myself. For example, cases labeled as insufficient information they would consider solved ! They also had some other little tricks. If a light were seen, they would say, "aircraft have lights, therefore, probable aircraft." Then, at the end of the year, when the statistics were made up, they would drop the "possible" or "probable" and simply call it aircraft.
STACY: What began to change your own perception of the phenomenon?
HYNEK: Two things, really. One was the completely negative and unyielding attitude of the Air Force. They wouldn't give UFOs the chance of existing, even if they were flying up and down the street in broad daylight. Everything had to have as explanation. I began to resent that, even though I basically felt the same way, because I still thought they weren't going about it in the right way. You can't assume that everything is black no matter what. Secondly, the caliber of the witnesses began to trouble me. Quite a few instances were reported by military pilots, for example, and I knew them to be fairly well-trained, so this is when I first began to think that, well, maybe there something to all this.
The famous "swamp gas" case which came later on finally pushed me over the edge. From that point on, I began to look at reports from a different angle, which was to say that some of them could be true UFOs.
STACY: As your own attitude changed, did the Air Force's attitude toward you change, too?
HYNEK: It certainly did, quite a bit, as a matter of fact. By way of background, I might add that the late Dr. James E. McDonald, a good friend of mine who was then an atmospheric meteorologist at the University of Arizona, and I had some fairly sharp words about it. He used to accuse me very much, saying you're the scientific consultant to the Air Force, you should be pounding on generals' doors and insisting on getting a better job done. I said, Jim, I was there, you weren't you don't know the mindset. They were under instruction from the Pentagon, following the Robertson Panel of 1953, that the whole subject had to be debunked, period, no question about it. That was the prevailing attitude. The panel was convened by the CIA, and I sat in on it, but I was not asked to sign the resolution. Had I been asked, I would not have signed it, because they took a completely negative attitude about everything. So when Jim McDonald used to accuse me of a sort of miscarriage of scientific justice, I had to tell him that had I done what he wanted, the generals would not have listened to me. They were already listening to Dr. Donald Menzel and the other boys over at the Harvard Astronomy Department as it was.
STACY: Did you think you would have been shown the front door and asked not to come back?
HYNEK: Inside of two weeks I imagine. You're familiar with the case of Tycho Brahe and Johannes Kepler from the history of astronomy? Brahe had the observations and didn't know what to do with them, and Kepler, who was nearsighted and couldn't make the observations, did. So essentially, I played Kepler to the Air Force's Tycho Brahe. I knew the Air Force was getting the data and I wanted a look at it, so I made very full use of the copying machines at Wright-Patterson. I kept practically a duplicate set of records because I knew that someday that data would be worth something. Toward the end, however, I was barely speaking with Major Quintanilla who was in charge. We had started as really good friends and then things got very bad because he had one lieutenant who was such a nincompoop, it seemed to me. Everything had to be "Jupiter or Venus" or this or that. You have no idea what a closed mind, what a closed attitude it was. I kept doggedly on, but I can safely say that the whole time I was with the Air Force we never had anything that resembled a really good scientific dialogue on the subject.
STACY: They weren't really interested in an actual investigation of the subject then?
HYNEK: They said they were, of course, but they would turn handsprings to keep a good case from getting to the "attention of the media". Any case they solved, they had no trouble talking to the media about. It was really very sad.... I think their greatest mistake in the early days, however, was not turning it over to the universities or some academic group. They regarded it as an intelligence matter and it became increasingly more and more embarrassing to them. After all, we paid good tax dollars to have the Air Force guard our skies and it would have been bad public relations for them to say, yes there's something up there, but we're helpless. They just couldn't do that, so they took the very human action of protecting their own interests. What they said was that we solved 96 per cent of the cases and that we could have solved the other four per cent if we had just tried harder.
STACY: Was it the famous Michigan sightings of 1966, explained away as "swamp gas" that finally did lead the Air Force to bring in a reputable university?
HYNEK: Yes, that, as you know, became something of a national joke and Michigan was soon being known as the "Swamp Gas State." Eventually, it resulted in a Congressional Hearing called for by then state Congressman, Gerald Ford, who of course later went on to become President. The investigation was turned over to the Brian O'Brien Committee who did a very good job. Had their recommendations been carried out, things might have turned out much better than they did. The recommended that UFOs be taken away from the Air Force and given to a group of universities, to study the thing in a as wide a way as possible. Well, they didn't go to a group, they went to a university and a man they were certain would be very hard-nosed about it, namely, Dr. Edward Condon at the University of Colorado. That was how the Condon Committee and eventually the Report came to be.
STACY: Were you ever called on to testify before, or advise the Committee?
HYNEK: In the early days they called on me to talk to them, to brief them, but that was the extent of it. They certainly didn't take any of my advice.
STACY: By 1968, the generally negative Condon Report was made public and the Air Force used its conclusions to get out of the UFO business. Were you still an official advisor or consultant at that time?
HYNEK: Oh, yes, I was with the Air Force right up until the very end, but it was just on paper. No one had cut the chicken's head off yet, but the chicken was dead. The last days at Blue Book were just a perfunctory shuffling of papers.
STACY: In terms of the UFO phenomenon itself, what was going on about this time?
HYNEK: Well, as you know, the Condon Report said that a group of scientists had looked at UFOs and that the subject was dead. The UFOs, of course, didn't bother to read the report and during the Flap of 1973, they came back in force.
11 Re: Gravitational Waves 2/13/2016, 6:51 am
Hospital Bob
Hallmarkgard wrote:
That's a brilliant parody. It took me a few minutes to see the kicker (the weather balloon labeled as swamp gas). Love it. lol
13 Re: Gravitational Waves 2/13/2016, 11:48 am
boards of FL
Think about it like this. When we "see" something, what that really means is that we're able to interpret light waves that manifest in the electromagnetic spectrum. More importantly stated, that information comes to us in a "wave like" form. Einstein theorized that gravity must necessarily propagate throughout the universe in a similar fashion. This recent discovery proves that fact.
But what that really means is that we can now observe the gravitational "wave like" signature of every "thing" that has mass and exhibits an influence on space and time.
We can't "see" a black hole. I place "see" in quotes because we can't really see black holes. They emit no light. We can only infer there presence by the absence of regularly occurring properties. But they do emit a gravitational signature, which propagates the universe in a wave like fashion. So we can now "see" them - as well as other undiscovered masses in the cosmos - in the same sense that we can "see" light.
But what that really means is that we can now observe the gravitational "wave like" signature of every "thing" that has mass and exhibits an influence on space and time.
We can't "see" a black hole. I place "see" in quotes because we can't really see black holes. They emit no light. We can only infer there presence by the absence of regularly occurring properties. But they do emit a gravitational signature, which propagates the universe in a wave like fashion. So we can now "see" them - as well as other undiscovered masses in the cosmos - in the same sense that we can "see" light.
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14 Re: Gravitational Waves 2/13/2016, 4:09 pm
Hospital Bob
When it comes to UFO's, I'm like Fox Mulder. In other words, I want to believe.
And I did believe for a long time. But now I don't. And there's one good reason why.
We have almost overnight gone from a very few people having big bulky cameras on their person, to virtually everyone now having a camera in his pocket.
And we still don't have any better UFO photos than we did before.
Doesn't add up.
And I did believe for a long time. But now I don't. And there's one good reason why.
We have almost overnight gone from a very few people having big bulky cameras on their person, to virtually everyone now having a camera in his pocket.
And we still don't have any better UFO photos than we did before.
Doesn't add up.
15 Re: Gravitational Waves 6/23/2016, 9:44 am
Guest
Guest
http://m.csmonitor.com/Science/2016/0623/Why-gravitational-waves-matter
There was big news in astrophysics this week: An experiment detected ripples in space-time,known as gravitational waves,created by two black holes colliding in space 1.4 billion light-years from Earth.
That certainly sounds … complicated. But what's the big deal,exactly? Why are scientists so excited about this new discovery?What does it tell them about the universe?Let's break it down.
The first significant thing about LIGO's direct detection of gravitational waves is that it happened at all.
But first,let's back up a bit and talk about Albert Einstein. He was a smart guy —he figured out a lot of really subtle stuff about the universe,including that space is not a fixed,rigid backdrop,like a stage on which cosmic events play out. Instead,Einstein showed that space is flexible and influenced by the objects and events within it. Very massive objects create curves in space,kind of like the way a bowling ball curves a mattress when placed on top of it.
(Einstein also showed that space and time are intimately linked —both are threads in the universal fabric that he called space-time. We'll gloss over this relationship for the sake of brevity.)
So what does this have to do with gravitational waves?If a massive object can curve space-time,then moving a massive object can create ripples in space-time. Think of a canoe moving across a lake,sending ripples across the surface of the water;or a mallet striking a drum, creating vibrations on the surface.
The Laser Interferometer Gravitational-Wave Observatory,better known as LIGO,was the first experiment ever to directly detect these ripples in space-time,so it's the first direct physical evidence that they actually exist. Its first detection came in September 2015,100 years after Einstein first predicted their existence. It's also been 40 years since people started working on the early incantations of the technology that LIGO uses to detect gravitational waves.
So these ripples in space-time confirm Einstein's theory (although it had already been shown to be fairly airtight). Gravitational waves are an extreme illustration of general relativity;in the past,those extreme examples existed only on paper,in the theoretical world. Data can always help scientists learn more about the universe,and if Einstein's theory needs to be adjusted (to make it compatible with quantum mechanics,for example),it's possible LIGO could find where. (LIGO's executive director said he's doubtful that LIGO will find these kinds of cracks or lose ends in Einstein's theory,but it is a possibility.)
But wait —there's more.
About these ads Black hole hunters
The LIGO discoveries have "launched a new era in astronomy," according to a statement from Northwestern University,where scientists are studying the gravitational waves to try to understand the black holes that created them. Other sources with LIGO have also talked about a "new era" or "new field of astrophysics," or have noted that LIGO is opening "a new window" to the universe.
That's a big claim. So how is LIGO driving this revolution?
Think of it this way: If every observatory and telescope in the history of humanity allowed people to "see" the universe,LIGO is now allowing us to "hear" it. And no one has ever heard the universe in this way before. Imagine what it would be like to suddenly gain not just a new view of the world around you,but the ability to detect an entirely different kind of information.
Just about every observatory or telescope that is studying the universe collects light —or,in some cases,other particles. Light comes in many flavors,such as X-rays,gamma-rays,visible light and radio waves. Different objects radiate different wavelengths of light. For example, your body produces enough heat to radiate infrared light,but it would take something as hot as an electric stove to radiate optical light. Looking at the universe in different wavelengths of lightreveals different objects and processes,and sometimes,it reveals things that are hidden for other reasons.
OK,but what if you want to look for an object that doesn't radiate light?
Black holes are called black holes because they have such a strong gravitational pull that even light can't get away from them. As a result, they're typically represented in images and illustrations as big,black spheres in space —they don't emit light,and they don't radiate light.
There are other ways to "see" black holes. For example, sometimes material around the black hole radiates light,and that can at least reveal the silhouette of one of these monsters. It's also possible to detect a black hole via its gravitational influence on stuff around it. (This is also how scientists detect dark matter,more mysterious stuff that makes up a big part of the universe.)
But for the black holes detected by LIGO,and most black holes between 10 and 100 times the mass of the sun,scientists with LIGO say it's unlikely that these techniques will work. That's because there's no material around these black holes;it gets flung away as the black holes circle around each other. That means these black holes are invisible —except to a gravitational-wave detector.
Plus,a purist will tell you that all of those above methods are indirect. If someone wants information created directly by the black hole,then gravitational waves are it.
So LIGO can see things that no other observatory can,and that's a big reason why people are calling this the beginning of a new era of astrophysics. LIGO will spot many other objects,including exploding stars (supernovas) and mergers between neutron stars,or the nuggets of leftover star explosions that are just slightly not dense enough to become black holes.
But there will also be great discoveries when LIGO works with light-based telescopes and observatories. Those instruments can "see" the universe,and LIGO can "hear" it —and they're best when used together,just as movies are best when they are both seen and heard or food is best when both tasted and smelled. "Multimessenger astronomy" refers to the combination of different kinds of astronomical information,such as light and gravitational waves. It's a new chapter in astrophysics,and LIGO has just given it a big boost.
LIGO's black holes
To get a taste of what kind of information gravitational waves can provide,take a look at LIGO's two detections. The first signal,detected in September 2015,was created by two black holes that had masses 29 and 36 times that of the sun,respectively. They created a new black hole with a mass just shy of their combined masses. (Some of the mass was lost as energy in the merger.) The second detection was also created by two black holes that had masses 7.5 and 14 times that of the sun,respectively.
The mass of a black hole provides some insight into how it formed. All four of these black holes were likely born from single,massive stars. Those stars burned brightly,but then ran out of fuel and collapsed on themselves,crunching matter into such an incredibly small space that the density of the remaining object cannot be clearly described by modern physics.
But the specifics of each star's living situation can vary,according to Vicky Kalogera,an astrophysicist at Northwestern University and a member of the LIGO Collaboration.
The smaller black holes detected by LIGO probably formed from stars that lived close together,stayed together after death and eventually spiraled toward each other and merged. Contrast that with black holes that are close to 20 times the mass of the sun,which likely formed ingreat clusters of stars (a "mosh pit" of stars,as the statement from Northwestern University described it).
How many black holes form in clusters,and how many form outside clusters?How many black hole mergers take place in the universe each day?How big do these black holes get?Can they reveal any new information about the monster black holes at the centers of galaxies, which have masses that range from millions to billions of times the mass of the sun?
These are questions that scientists now have a better shot at answering because they can detect black hole mergers directly,and quickly figure out the exact masses of those black holes.
Just the beginning
LIGO detected two confirmed black hole mergers in its first science run,which lasted about six months. Currently,LIGO is operating at only about 40 percent of the sensitivity it was designed to achieve. Gradual improvements by the LIGO team will slowly drive that percentage up,and with each bump in sensitivity,LIGO is expected to detect more and more objects. According to David Reitze,executive director of the LIGO Laboratory,if the detector is 25 percent more sensitive in its next run (which starts in September),the LIGO Collaboration can expect six to eight detections,instead of two.
Meanwhile,a companion gravitational-wave detector is scheduled to go online in Italy in January,and there are plans to have detectors in Japan and India in the future. A space-based experiment is laying the groundwork for space-based gravitational-wave detectors. And a collaboration of scientists is working on measuring gravitational waves by studying pulsars,or neutron stars that radiate beams of radio waves.
LIGO's discovery means a lot of things to the astrophysics community; it might actually be the beginning of a new era.
There was big news in astrophysics this week: An experiment detected ripples in space-time,known as gravitational waves,created by two black holes colliding in space 1.4 billion light-years from Earth.
That certainly sounds … complicated. But what's the big deal,exactly? Why are scientists so excited about this new discovery?What does it tell them about the universe?Let's break it down.
The first significant thing about LIGO's direct detection of gravitational waves is that it happened at all.
But first,let's back up a bit and talk about Albert Einstein. He was a smart guy —he figured out a lot of really subtle stuff about the universe,including that space is not a fixed,rigid backdrop,like a stage on which cosmic events play out. Instead,Einstein showed that space is flexible and influenced by the objects and events within it. Very massive objects create curves in space,kind of like the way a bowling ball curves a mattress when placed on top of it.
(Einstein also showed that space and time are intimately linked —both are threads in the universal fabric that he called space-time. We'll gloss over this relationship for the sake of brevity.)
So what does this have to do with gravitational waves?If a massive object can curve space-time,then moving a massive object can create ripples in space-time. Think of a canoe moving across a lake,sending ripples across the surface of the water;or a mallet striking a drum, creating vibrations on the surface.
The Laser Interferometer Gravitational-Wave Observatory,better known as LIGO,was the first experiment ever to directly detect these ripples in space-time,so it's the first direct physical evidence that they actually exist. Its first detection came in September 2015,100 years after Einstein first predicted their existence. It's also been 40 years since people started working on the early incantations of the technology that LIGO uses to detect gravitational waves.
So these ripples in space-time confirm Einstein's theory (although it had already been shown to be fairly airtight). Gravitational waves are an extreme illustration of general relativity;in the past,those extreme examples existed only on paper,in the theoretical world. Data can always help scientists learn more about the universe,and if Einstein's theory needs to be adjusted (to make it compatible with quantum mechanics,for example),it's possible LIGO could find where. (LIGO's executive director said he's doubtful that LIGO will find these kinds of cracks or lose ends in Einstein's theory,but it is a possibility.)
But wait —there's more.
About these ads Black hole hunters
The LIGO discoveries have "launched a new era in astronomy," according to a statement from Northwestern University,where scientists are studying the gravitational waves to try to understand the black holes that created them. Other sources with LIGO have also talked about a "new era" or "new field of astrophysics," or have noted that LIGO is opening "a new window" to the universe.
That's a big claim. So how is LIGO driving this revolution?
Think of it this way: If every observatory and telescope in the history of humanity allowed people to "see" the universe,LIGO is now allowing us to "hear" it. And no one has ever heard the universe in this way before. Imagine what it would be like to suddenly gain not just a new view of the world around you,but the ability to detect an entirely different kind of information.
Just about every observatory or telescope that is studying the universe collects light —or,in some cases,other particles. Light comes in many flavors,such as X-rays,gamma-rays,visible light and radio waves. Different objects radiate different wavelengths of light. For example, your body produces enough heat to radiate infrared light,but it would take something as hot as an electric stove to radiate optical light. Looking at the universe in different wavelengths of lightreveals different objects and processes,and sometimes,it reveals things that are hidden for other reasons.
OK,but what if you want to look for an object that doesn't radiate light?
Black holes are called black holes because they have such a strong gravitational pull that even light can't get away from them. As a result, they're typically represented in images and illustrations as big,black spheres in space —they don't emit light,and they don't radiate light.
There are other ways to "see" black holes. For example, sometimes material around the black hole radiates light,and that can at least reveal the silhouette of one of these monsters. It's also possible to detect a black hole via its gravitational influence on stuff around it. (This is also how scientists detect dark matter,more mysterious stuff that makes up a big part of the universe.)
But for the black holes detected by LIGO,and most black holes between 10 and 100 times the mass of the sun,scientists with LIGO say it's unlikely that these techniques will work. That's because there's no material around these black holes;it gets flung away as the black holes circle around each other. That means these black holes are invisible —except to a gravitational-wave detector.
Plus,a purist will tell you that all of those above methods are indirect. If someone wants information created directly by the black hole,then gravitational waves are it.
So LIGO can see things that no other observatory can,and that's a big reason why people are calling this the beginning of a new era of astrophysics. LIGO will spot many other objects,including exploding stars (supernovas) and mergers between neutron stars,or the nuggets of leftover star explosions that are just slightly not dense enough to become black holes.
But there will also be great discoveries when LIGO works with light-based telescopes and observatories. Those instruments can "see" the universe,and LIGO can "hear" it —and they're best when used together,just as movies are best when they are both seen and heard or food is best when both tasted and smelled. "Multimessenger astronomy" refers to the combination of different kinds of astronomical information,such as light and gravitational waves. It's a new chapter in astrophysics,and LIGO has just given it a big boost.
LIGO's black holes
To get a taste of what kind of information gravitational waves can provide,take a look at LIGO's two detections. The first signal,detected in September 2015,was created by two black holes that had masses 29 and 36 times that of the sun,respectively. They created a new black hole with a mass just shy of their combined masses. (Some of the mass was lost as energy in the merger.) The second detection was also created by two black holes that had masses 7.5 and 14 times that of the sun,respectively.
The mass of a black hole provides some insight into how it formed. All four of these black holes were likely born from single,massive stars. Those stars burned brightly,but then ran out of fuel and collapsed on themselves,crunching matter into such an incredibly small space that the density of the remaining object cannot be clearly described by modern physics.
But the specifics of each star's living situation can vary,according to Vicky Kalogera,an astrophysicist at Northwestern University and a member of the LIGO Collaboration.
The smaller black holes detected by LIGO probably formed from stars that lived close together,stayed together after death and eventually spiraled toward each other and merged. Contrast that with black holes that are close to 20 times the mass of the sun,which likely formed ingreat clusters of stars (a "mosh pit" of stars,as the statement from Northwestern University described it).
How many black holes form in clusters,and how many form outside clusters?How many black hole mergers take place in the universe each day?How big do these black holes get?Can they reveal any new information about the monster black holes at the centers of galaxies, which have masses that range from millions to billions of times the mass of the sun?
These are questions that scientists now have a better shot at answering because they can detect black hole mergers directly,and quickly figure out the exact masses of those black holes.
Just the beginning
LIGO detected two confirmed black hole mergers in its first science run,which lasted about six months. Currently,LIGO is operating at only about 40 percent of the sensitivity it was designed to achieve. Gradual improvements by the LIGO team will slowly drive that percentage up,and with each bump in sensitivity,LIGO is expected to detect more and more objects. According to David Reitze,executive director of the LIGO Laboratory,if the detector is 25 percent more sensitive in its next run (which starts in September),the LIGO Collaboration can expect six to eight detections,instead of two.
Meanwhile,a companion gravitational-wave detector is scheduled to go online in Italy in January,and there are plans to have detectors in Japan and India in the future. A space-based experiment is laying the groundwork for space-based gravitational-wave detectors. And a collaboration of scientists is working on measuring gravitational waves by studying pulsars,or neutron stars that radiate beams of radio waves.
LIGO's discovery means a lot of things to the astrophysics community; it might actually be the beginning of a new era.
16 Re: Gravitational Waves 6/23/2016, 10:23 am
Floridatexan
http://www.universetoday.com/118640/uncovering-the-starry-night-planck-images-touch-upon-van-gogh/
New images returned by the Planck telescope (right) begin to rival the complexity and beauty of a great artists imagination - Starry Night.A visulization of the Planck data represents the interaction of interstellar dust with the galactic magnetic field. Color defines the intensity of dust emissions and the measurements of polarized light reveals the direction of the magnetic field lines. (Credits: Vincent Van Gogh, ESA)
New images returned by the Planck telescope (right) begin to rival the complexity and beauty of a great artists imagination - Starry Night.A visulization of the Planck data represents the interaction of interstellar dust with the galactic magnetic field. Color defines the intensity of dust emissions and the measurements of polarized light reveals the direction of the magnetic field lines. (Credits: Vincent Van Gogh, ESA)
17 Re: Gravitational Waves 6/23/2016, 10:49 am
Guest
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Wow... that's a trip. It's like he subconsciously sensed gravity.
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