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Groups > sci.physics > #617210
| From | kensi <kkensington01@gmail.invalid> |
|---|---|
| Newsgroups | sci.physics, alt.fan.cyberchicken |
| Subject | Re: Quasar redshift |
| Date | 2017-02-06 10:35 -0500 |
| Organization | Aioe.org NNTP Server |
| Message-ID | <o7a549$4gk$1@gioia.aioe.org> (permalink) |
| References | <58988bf8$0$34580$c3e8da3$dbd57e7@news.astraweb.com> |
Cross-posted to 2 groups.
On 2/6/2017 9:45 AM, vallor wrote: > Hey, I had an astrophysics question, and I understand there are > astrophysicists roaming these hallowed halls... > > I'm wondering if the redshift seen with quasars might be due to something > other than distance, such as perhaps the gravity of their black holes? > > I see here: > > https://phys.org/news/2010-04-discovery-quasars-dont-dilation-mystifies.html [snip] The more distant quasars are younger. Quasars are black holes. Younger ones are less massive; they haven't had time to eat as much stuff yet. Smaller things oscillate faster (think of a pendulum). The farther quasars are both faster (because they're smaller) and slower (because of time dilation). The two effects roughly cancel out, since both are roughly linear in distance, assuming the growth of quasar black holes is roughly linear in time, which is reasonable -- it would be quadratic, but for the messy way black holes eat, accretion disks and jets and all, and that they end up hollowing out a volume around them -- a low-hanging fruit effect that contributes to growth early on, but depletes opportunities later. Actually, supermassive black holes gain much more mass from gradually accumulating gas than from accumulating stars, gas that in turn accreted onto their host galaxies. As the universe expands, though, the intergalactic medium thins out, reducing the gas available to those supermassive black holes. There are further complications; see e.g. https://academic.oup.com/mnras/article/363/1/2/1300118/How-do-galaxies-get-their-gas Hawkins's own paper suggests this as one possible explanation for his observations, by the way. -- "To explain the unknown by the known is a logical procedure; to explain the known by the unknown is a form of theological lunacy." ~David Brooks "I get fooled all the time by the constant hosiery parade in here." ~Checkmate
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Quasar redshift vallor <vallor@cultnix.org> - 2017-02-06 14:45 +0000
Re: Quasar redshift kensi <kkensington01@gmail.invalid> - 2017-02-06 10:35 -0500
Re: Quasar redshift john <johnsefton288@gmail.com> - 2017-02-06 07:50 -0800
Re: Quasar redshift vallor <vallor@cultnix.org> - 2017-02-06 16:28 +0000
Re: Quasars are dying out because gravity itself is evaporating away. moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-02-06 18:23 +0000
Re: Entropy increases, eternally, without beginning or end. moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-02-06 21:47 +0000
Re: Entropy increases, eternally, without beginning or end. noTthaTguY <abu.kuanysh05@gmail.com> - 2017-02-06 13:59 -0800
Re: Clocks tick _forward, not backwards. benj <benj@nobody.net> - 2017-02-07 16:31 -0500
Re: Clocks tick _forward, not backwards. kensi <kkensington01@gmail.invalid> - 2017-02-08 13:04 -0500
Re: Clocks tick _forward, not backwards. "reber g=emc^2" <herbertglazier0@gmail.com> - 2017-02-08 12:34 -0800
Re: Clocks tick _forward, not backwards. "hanson" <hanson@quick.net> - 2017-02-08 16:22 -0800
Re: Clocks tick _forward, not backwards. john <johnsefton288@gmail.com> - 2017-02-08 17:08 -0800
Re: Clocks tick _forward, not backwards. noTthaTguY <abu.kuanysh05@gmail.com> - 2017-02-08 22:00 -0800
Re: Clocks tick _forward, not backwards. benj <benj@nobody.net> - 2017-02-09 17:33 -0500
Re: Clocks tick _forward, not backwards. john <johnsefton288@gmail.com> - 2017-02-09 15:07 -0800
Re: Clocks tick _forward, not backwards. benj <benj@nobody.net> - 2017-02-09 18:30 -0500
Re: Clocks tick _forward, not backwards. "hanson" <hanson@quick.net> - 2017-02-09 15:31 -0800
whence clocks whould tickenn noTthaTguY <abu.kuanysh05@gmail.com> - 2017-02-09 19:58 -0800
Re: whence clocks whould tickenn noTthaTguY <abu.kuanysh05@gmail.com> - 2017-02-15 00:35 -0800
Re: Clocks tick _forward, not backwards. HVAC <mr.hvac@gmail.com> - 2017-02-09 17:14 -0800
Re: Clocks tick _forward, not backwards. benj <benj@nobody.net> - 2017-02-09 21:05 -0500
Re: Clocks tick _forward, not backwards. HVAC <mr.hvac@gmail.com> - 2017-02-11 08:54 -0800
Re: Clocks tick _forward, not backwards. benj <benj@nobody.net> - 2017-02-11 17:54 -0500
Re: Clocks tick _forward, not backwards. noTthaTguY <abu.kuanysh05@gmail.com> - 2017-02-12 00:58 -0800
Re: Clocks tick _forward, not backwards. HVAC <mr.hvac@gmail.com> - 2017-02-12 03:25 -0800
Re: Clocks tick _forward, not backwards. benj <benj@nobody.net> - 2017-02-13 16:04 -0500
Re: Clocks tick _forward, not backwards. HVAC <mr.hvac@gmail.com> - 2017-02-12 03:26 -0800
Re: Clocks tick _forward, not backwards. benj <benj@nobody.net> - 2017-02-13 16:05 -0500
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-11 18:11 +1100
Re: Clocks tick _forward, not backwards. Janithor <Janithor@comcast.net> - 2017-02-10 23:35 -0800
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-11 18:55 +1100
Re: Clocks tick _forward, not backwards. Janithor <Janithor@comcast.net> - 2017-02-11 00:11 -0800
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-11 19:46 +1100
Re: Clocks tick _forward, not backwards. Janithor <Janithor@comcast.net> - 2017-02-11 00:50 -0800
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-11 20:07 +1100
Re: Clocks tick _forward, not backwards. Janithor <Janithor@comcast.net> - 2017-02-11 01:12 -0800
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-11 20:15 +1100
Re: Clocks tick _forward, not backwards. Janithor <Janithor@comcast.net> - 2017-02-11 01:19 -0800
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-11 20:26 +1100
Re: Clocks tick _forward, not backwards. Janithor <Janithor@comcast.net> - 2017-02-11 01:32 -0800
Re: Clocks tick _forward, not backwards. kensi <kkensington01@gmail.invalid> - 2017-02-11 05:06 -0500
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-11 22:26 +1100
Re: Clocks tick _forward, not backwards. kensi <kkensington01@gmail.invalid> - 2017-02-11 06:44 -0500
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-12 00:11 +1100
Re: Clocks tick _forward, not backwards. Nadegda <nad318b404@gmail.invalid> - 2017-02-11 20:54 +0000
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-12 09:45 +1100
Re: Clocks tick _forward, not backwards. Nadegda <nad318b404@gmail.invalid> - 2017-02-11 23:17 +0000
Re: Clocks tick _forward, not backwards. Kadaitcha Man <nospam.nospam.nospam@gmail.com> - 2017-02-12 15:43 +1100
Re: Clocks tick _forward, not backwards. kensi <kkensington01@gmail.invalid> - 2017-02-12 05:09 -0500
Quasar redshift HVAC <mr.hvac@gmail.com> - 2017-02-07 08:56 -0800
Quasar redshift john <johnsefton288@gmail.com> - 2017-02-07 09:12 -0800
Re: Quasar redshift benj <benj@nobody.net> - 2017-02-07 16:53 -0500
Re: Quasar redshift noTthaTguY <abu.kuanysh05@gmail.com> - 2017-02-07 15:47 -0800
Re: Quasar redshift Serg Io <invliad@invalid.com> - 2017-02-07 18:47 -0600
The dopplerianS noTthaTguY <abu.kuanysh05@gmail.com> - 2017-02-07 19:20 -0800
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