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GW190521 article. This is not a forum for general discussion of the article's subject. |
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A news item involving GW190521 was featured on Wikipedia's Main Page in the In the news section on 4 September 2020. |
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Created talk-page for the " GW190521g" article - Enjoy! :) - and - Stay Safe and Healthy !! - Drbogdan ( talk) 02:03, 26 June 2020 (UTC)
If interested, ITN discussion at => Wikipedia:In the news/Candidates#GW190521 - Drbogdan ( talk) 01:24, 4 September 2020 (UTC)
The article in the New York Times says "7 billion years ago" in two spots and "17 billion light-years away" in one spot that I saw. One might assume that "7 billion years ago" implies "7 billion light years away," because gravitational waves travel at the speed of light. The waves were emitted from a distance of 7 billion light years at a time 7 billion years ago. In the intervening seven billion years of elapsed time, the Universe expanded and the location of the event, previously at a distance of 7 billion light years, is _now_ at a distance of 17 billion light years (the meanings of _ago_, _now_, and _distance_ are not trivial, requiring careful calculations in standardized cosmological coordinate systems and reference frames). 97.113.128.35 ( talk) 15:05, 5 September 2020 (UTC)
References
How can this be 17 BILLION light years away when that's greater than the age of the universe? -- Veggies ( talk) 13:49, 4 September 2020 (UTC)
@ Veggies: Thank you for your Question - this NYT quote may also help => "The event unfolded at an almost unimaginable distance from Earth — in a spot that is now 17 billion light-years away according to standard cosmological calculations that describe an expanding universe." [1] - in any case - Stay Safe and Healthy !! - Drbogdan ( talk) 14:13, 4 September 2020 (UTC)
That is possibly a typo. This article says Seven billion. https://www.bbc.com/news/science-environment-53993937 [2] Mr. 123453334 ( talk) 23:35, 14 September 2020 (UTC)
The 5.3 Gpc number is coming from the original paper, but it is not the "distance", it is the "luminosity distance". The luminosity distance is very different from the actual distance. Journalists probably took the luminosity distance number and confused it for the actual distance. GehNgiS ( talk) 13:49, 8 August 2021 (UTC)
I contacted R. Abbott (the first author in the paper) who was kind enough to get me an answer from one of his colleagues.
They confirmed that the red shift must be taken into account and they pointed me to an online calculator: http://www.astro.ucla.edu/~wright/DlttCalc.html
In this calculator, if you enter "7.05" for "light travel time in Gyr" and click on "flat", the calculator will give "The luminosity distance DL is 5302.7 Mpc or 17.295 Gly."
To sum it up, the observed luminosity distance is 5.3 Gpc or 17.3 billion light-years. However, this is not the actual distance. This 5.3 Gpc luminosity distance, assuming the universe is flat, means that the light/gravity waves traveled for 7.05 billion years, which gives a distance of 7.05 billion light-years. GehNgiS ( talk) 19:17, 11 August 2021 (UTC)
References
What if anything do we need to do, for this article to be rated better than Start-class? Nick Levine ( talk) 02:27, 9 September 2020 (UTC)
I introduced this template earlier today, so that note 1 could contain a citation reference. Since then the iOS app has been unable to display the page. All web browsers I tested on are fine with it.
Do we care? Shall I undo my earlier change? Does anyone know of a better way round this?
(I have written to the app maintainers. I don't know whether we can expect a speedy response.)
Nick Levine ( talk) 16:45, 9 September 2020 (UTC)
The already-posted ITN blurb says
Scientists confirm the first detection, using gravitational-wave astronomy, of a black hole in the upper mass gap.
However, the article currently only mentions that these black holes are in the mass gap, but it does not directly say that this was the first detection of a black hole in the upper mass gap. Could someone reference and add the actual ITN claim into the article?
Pinging the ITN-posting admin ( Tone) and editors actively involved in updating the article ( Drbogdan & Nick Levine). — MarkH21 talk 09:22, 14 September 2020 (UTC)
The article states: "If this explanation is correct, the flare should repeat after about 1.6 years". That moment was November/December 2020, was it observed?
This is the
talk page for discussing improvements to the
GW190521 article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google ( books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
A news item involving GW190521 was featured on Wikipedia's Main Page in the In the news section on 4 September 2020. |
This article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||
|
Created talk-page for the " GW190521g" article - Enjoy! :) - and - Stay Safe and Healthy !! - Drbogdan ( talk) 02:03, 26 June 2020 (UTC)
If interested, ITN discussion at => Wikipedia:In the news/Candidates#GW190521 - Drbogdan ( talk) 01:24, 4 September 2020 (UTC)
The article in the New York Times says "7 billion years ago" in two spots and "17 billion light-years away" in one spot that I saw. One might assume that "7 billion years ago" implies "7 billion light years away," because gravitational waves travel at the speed of light. The waves were emitted from a distance of 7 billion light years at a time 7 billion years ago. In the intervening seven billion years of elapsed time, the Universe expanded and the location of the event, previously at a distance of 7 billion light years, is _now_ at a distance of 17 billion light years (the meanings of _ago_, _now_, and _distance_ are not trivial, requiring careful calculations in standardized cosmological coordinate systems and reference frames). 97.113.128.35 ( talk) 15:05, 5 September 2020 (UTC)
References
How can this be 17 BILLION light years away when that's greater than the age of the universe? -- Veggies ( talk) 13:49, 4 September 2020 (UTC)
@ Veggies: Thank you for your Question - this NYT quote may also help => "The event unfolded at an almost unimaginable distance from Earth — in a spot that is now 17 billion light-years away according to standard cosmological calculations that describe an expanding universe." [1] - in any case - Stay Safe and Healthy !! - Drbogdan ( talk) 14:13, 4 September 2020 (UTC)
That is possibly a typo. This article says Seven billion. https://www.bbc.com/news/science-environment-53993937 [2] Mr. 123453334 ( talk) 23:35, 14 September 2020 (UTC)
The 5.3 Gpc number is coming from the original paper, but it is not the "distance", it is the "luminosity distance". The luminosity distance is very different from the actual distance. Journalists probably took the luminosity distance number and confused it for the actual distance. GehNgiS ( talk) 13:49, 8 August 2021 (UTC)
I contacted R. Abbott (the first author in the paper) who was kind enough to get me an answer from one of his colleagues.
They confirmed that the red shift must be taken into account and they pointed me to an online calculator: http://www.astro.ucla.edu/~wright/DlttCalc.html
In this calculator, if you enter "7.05" for "light travel time in Gyr" and click on "flat", the calculator will give "The luminosity distance DL is 5302.7 Mpc or 17.295 Gly."
To sum it up, the observed luminosity distance is 5.3 Gpc or 17.3 billion light-years. However, this is not the actual distance. This 5.3 Gpc luminosity distance, assuming the universe is flat, means that the light/gravity waves traveled for 7.05 billion years, which gives a distance of 7.05 billion light-years. GehNgiS ( talk) 19:17, 11 August 2021 (UTC)
References
What if anything do we need to do, for this article to be rated better than Start-class? Nick Levine ( talk) 02:27, 9 September 2020 (UTC)
I introduced this template earlier today, so that note 1 could contain a citation reference. Since then the iOS app has been unable to display the page. All web browsers I tested on are fine with it.
Do we care? Shall I undo my earlier change? Does anyone know of a better way round this?
(I have written to the app maintainers. I don't know whether we can expect a speedy response.)
Nick Levine ( talk) 16:45, 9 September 2020 (UTC)
The already-posted ITN blurb says
Scientists confirm the first detection, using gravitational-wave astronomy, of a black hole in the upper mass gap.
However, the article currently only mentions that these black holes are in the mass gap, but it does not directly say that this was the first detection of a black hole in the upper mass gap. Could someone reference and add the actual ITN claim into the article?
Pinging the ITN-posting admin ( Tone) and editors actively involved in updating the article ( Drbogdan & Nick Levine). — MarkH21 talk 09:22, 14 September 2020 (UTC)
The article states: "If this explanation is correct, the flare should repeat after about 1.6 years". That moment was November/December 2020, was it observed?