Meanwhile in Space

[Vibe]

I wonder though, for how long has this experiment been running? If we've been listening for months and we only get something that matches now, does that frequency of detection actually match what we would expect, knowing the expected frequency of the events that could trigger the system?

It's been running for years. They detected now because they improved the technology/machinery, from what I heard. They're planning to improve it even more, increasing the range of detection.
Initial LIGO operations between 2002 and 2010 did not detect any gravitational waves. In 2004, under Barish, the funding and groundwork were laid for the next phase of LIGO development (called "Enhanced LIGO"). This was followed by a multi-year shut-down while the detectors were replaced by much improved "Advanced LIGO" versions.[23] Much of the research and development work for the LIGO/aLIGO machines was based on pioneering work for the GEO600 detector at Hannover, Germany.[24][25][26] By February 2015, the detectors were brought into engineering mode in both locations

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Apparently they also did fake signals here and there to see if the scientists at LIGO could differentiate between the real thing and the fake one. I belive they also knew the two black holes would merge based on surrounding cosmic objects. So if I understand correctly, they heard it first then they also detected it with the lasers.

[The_Bloody_Nine]

I wonder though, for how long has this experiment been running? If we've been listening for months and we only get something that matches now, does that frequency of detection actually match what we would expect, knowing the expected frequency of the events that could trigger the system?

As far as I remember we can expect much more frequent detections and there may have been other g-waves detected since the one from last year. They only have been so busy proofing that the one was nearly 100% certainly true. Also like Vibe said since February LIGO is shut down to make further improvements, I guess there will be much more frequent detections with further improvements and better understanding of this complete new way of 'perception'.


cool other topic:

http://www.universetoday.com/127527/nasa-thinks-theres-a-way-to-get-to-mars-in-3-days/

[Kafein]

Well, if we matched the detection to an actual, defined event then my point is moot.

[Vibe]

Well, if we matched the detection to an actual, defined event then my point is moot.

What do you mean by actual, defined event? Something that we can observe or what?

[Kafein]

Something like "this binary system right there".

[Vibe]

Something like "this binary system right there".

Kinda hard to point at something you don't see. But apparently they need another facility in Europe to triangulate to the source location (distance between the two in US not far enough? dunno), then we can point and say 'right there'.

[Kafein]

Kinda hard to point at something you don't see. But apparently they need another facility in Europe to triangulate to the source location (distance between the two in US not far enough? dunno), then we can point and say 'right there'.

That I can easily understand. There's "tri" in triangulate. Finding the origin from two points is going to leave you with a whole surface. Some sort of funny two-sheeted hyperboloid where a section would look like when you put this into wolfram alpha: ((x - 5)^2 + y^2)^(1/2) -  (x^2 + y^2)^(1/2) = 1. You need a third origin to further pinpoint the location of the source, and then on the top of my mind you will still have a whole curve of possibilities until you add a fourth point.

That at least is true if we start from the assumption that we only know the distance between the experiments and not the distance to the thing being detected. If we do it's merely a trilateration.

[Vibe]

That I can easily understand. There's "tri" in triangulate. Finding the origin from two points is going to leave you with a whole surface. Some sort of funny two-sheeted hyperboloid where a section would look like when you put this into wolfram alpha: ((x - 5)^2 + y^2)^(1/2) -  (x^2 + y^2)^(1/2) = 1. You need a third origin to further pinpoint the location of the source, and then on the top of my mind you will still have a whole curve of possibilities until you add a fourth point.

That at least is true if we start from the assumption that we only know the distance between the experiments and not the distance to the thing being detected. If we do it's merely a trilateration.

Actually the "tri" in triangulate comes from earth's position relative to the sun, at least when it comes to measuring distances to stars.

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I don't know how it's going to work in this case though, since we're not using light to determine location. Might be that the gravity waves change much faster than 6 months it takes for earth to get into correct position - in fact I have no idea how fast that black hole merger was.

[Kafein]

Actually the "tri" in triangulate comes from earth's position relative to the sun, at least when it comes to measuring distances to stars.

That's not where the tri comes from. The problem of finding the distance to a star is completely different. You know what the direction to the star is, you simply don't know how far it is. In the case of this experiment, I'm not even convinced we know where to look, and that's the problem I was trying to formulate.

The experiment on gravitational waves relies on very tight temporal constraints that do not exist when you want to know the distance to a star. And if we try to look at a recurring event with the same device, you'd have to figure out what to listen to, 6 months later. My understanding is that we roughly know how a binary system sounds like, but I don't think we can tell them apart. For that you need to at least have an idea of where it is when you do the experiment at a given time.

It's very similar to how your brain has to take two audio inputs and figure out where the sounds are coming from. To achieve this you need to be able to categorize the sounds first and infer the position for every sound separately afterwards.

[The_Bloody_Nine]

Only watched it partially, but it's nice because it reminds you what it actually means to get into GEO. Good job on the coverage with those nice animations and informations their giving.

[The_Bloody_Nine]

[The_Bloody_Nine]

I know always the same topic, but those are some damn nice pictures imo:

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(click to view more)

[Vibe]

Spider Nebula
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[Gmnotutoo]

What are everyone's personal thoughts on what happens involving a blackhole? I'm curious to what other people think about this because there a lot of possibilities.

I'm under the impression that either every black-hole contains it's own universe or they are actually stars, just really tiny heavy ones condensed into a single point.

[Leshma]

Dunno about black holes containing whole universe(s) but latest theory from Stephen Hawking says something along lines that matter black holes "regurgitate" could contain information about history of our universe.

http://www.independent.co.uk/news/science/stephen-hawking-black-hole-hairs-information-problem-a6819986.html

Apparently, some matter does leave the black hole and information it carries is "encrypted" (randomized, all over the place) or in other ways currently useless for us. My personal belief is that same thing happens with our conscience/mind&soul when we die. Energy transforms but is information it carries truly lost? Maybe there are ways to fix the glass after it shatters, to go back in time? It would render basic laws of physics useless but isn't that we all desire? Anyway, black holes are best thing in universe to research if you want to find out is our knowledge about universe set in stone or just subset of bigger knowledge bank that governs our and maybe many more universes. Problem is, we have no means to directly experiment on black holes. For the time being.