Comments on: Guest Post: Evalyn Gates on Cosmic Magnification (or — Invasion of the Giant Blue Space Amoebas) http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/ Random samplings from a universe of ideas. Sun, 22 Nov 2009 04:02:38 -0600 http://wordpress.org/?v=2.8.4 hourly 1 By: Peter Jackson http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-98658 Peter Jackson Fri, 25 Sep 2009 15:10:07 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-98658 Dr Gates. Has anyone noticed or checked for any scale correlation between the lensing galaxies apparent gravitational mass anomalies and redshift? I've been working on a model which, as a by product, would predict such correlation, and significant discrepancies in the Gmass mismatches, (some masses should be way too high), and explain them. It's not really an astronomical model and I'm not an astronomer, but it's a fundamental physics matter. It could also throw up possible lensing structure anomalies for any blue shifted lensing galaxies compared to redshifted lenses. Also, is 'over 3 years' the highest delay recorded? Any relevant comments gratefully received. Peter Jackson Dr Gates. Has anyone noticed or checked for any scale correlation between the lensing galaxies apparent gravitational mass anomalies and redshift?
I’ve been working on a model which, as a by product, would predict such correlation, and significant discrepancies in the Gmass mismatches, (some masses should be way too high), and explain them. It’s not really an astronomical model and I’m not an astronomer, but it’s a fundamental physics matter.
It could also throw up possible lensing structure anomalies for any blue shifted lensing galaxies compared to redshifted lenses.
Also, is ‘over 3 years’ the highest delay recorded?
Any relevant comments gratefully received.
Peter Jackson

]]> By: allenEv http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-91639 allenEv Sat, 22 Aug 2009 15:15:12 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-91639 Hi Dr. Gates, it was a great pleasure to attend your Hayden Planetarium lecture and I am pretty far along in reading your book that you so graciously signed. Do these lensed images afford us the opportunity to determine the galactic rotation curves of these most distant/ancient galaxies? If so, do these ancient galaxies exhibit the same flat curve or are they more/less Newtonian than more modern galaxies? Best. -Allen Everhart Hi Dr. Gates, it was a great pleasure to attend your Hayden Planetarium lecture and I am pretty far along in reading your book that you so graciously signed. Do these lensed images afford us the opportunity to determine the galactic rotation curves of these most distant/ancient galaxies? If so, do these ancient galaxies exhibit the same flat curve or are they more/less Newtonian than more modern galaxies?

Best.
-Allen Everhart

]]> By: Galaxies in your iPhone | Cosmic Variance | Discover Magazine http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-88230 Galaxies in your iPhone | Cosmic Variance | Discover Magazine Thu, 30 Jul 2009 20:16:24 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-88230 [...] gotten a little bent out of shape over gravitational lensing recently (see here and here). But the fun doesn’t stop: gravitational lensing has now officially come into the [...] [...] gotten a little bent out of shape over gravitational lensing recently (see here and here). But the fun doesn’t stop: gravitational lensing has now officially come into the [...]

]]> By: Chris W. http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-86537 Chris W. Fri, 24 Jul 2009 17:10:01 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-86537 About Sean's comment (#3) I think one has to consider the general attitude in such a society towards theorizing in physics. In short, its members might be content with hacking solutions to the engineering problems caused by their mysterious GPS timing anomalies; they would rely on epicycles instead of deep understanding. Of course, this assumes that such hacking would be effective in finding practical solutions:<blockquote>There is nothing quite so practical as a good theory.     --- <a href="http://en.wikipedia.org/wiki/John_R._Pierce" rel="nofollow">John R. Pierce</a></blockquote> About Sean’s comment (#3) I think one has to consider the general attitude in such a society towards theorizing in physics. In short, its members might be content with hacking solutions to the engineering problems caused by their mysterious GPS timing anomalies; they would rely on epicycles instead of deep understanding.

Of course, this assumes that such hacking would be effective in finding practical solutions:

There is nothing quite so practical as a good theory.
    — John R. Pierce

]]> By: Eclipse and relativity « A Man With A Ph.D. http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-85728 Eclipse and relativity « A Man With A Ph.D. Wed, 22 Jul 2009 16:08:08 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-85728 [...] total solar eclipse of the Century swept across Asia. And a few days ago Evalyn Gates provided a wonderful guest post on gravitational lensing. This seems like an opportune time to note that gravitational lensing and [...] [...] total solar eclipse of the Century swept across Asia. And a few days ago Evalyn Gates provided a wonderful guest post on gravitational lensing. This seems like an opportune time to note that gravitational lensing and [...]

]]> By: Gravity and light | Cosmic Variance | Discover Magazine http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-85551 Gravity and light | Cosmic Variance | Discover Magazine Wed, 22 Jul 2009 07:15:11 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-85551 [...] total solar eclipse of the Century swept across Asia. And a few days ago Evalyn Gates provided a wonderful guest post on gravitational lensing. This seems like an opportune time to note that gravitational lensing and [...] [...] total solar eclipse of the Century swept across Asia. And a few days ago Evalyn Gates provided a wonderful guest post on gravitational lensing. This seems like an opportune time to note that gravitational lensing and [...]

]]> By: Evalyn Gates http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-85066 Evalyn Gates Tue, 21 Jul 2009 06:55:05 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-85066 Christopher: you're right -- we're seeing each snapshot at a different time, and there are actually two effects that contribute to a time delay between images. First is the one you mention -- the length of the path the light travels for each image is different. Second is a general relativistic effect (known as the Shapiro delay) -- the different light paths travel through different regions of the gravitational field of the cluster, and the stronger the field, the larger the delay. The time delay hasn't been estimated for these images, but it has actually been measured for another cluster lens (SDSS J1004) where there are 5 images of a distant quasar. Here the Shapiro delay dominates over the path length delay, and so the light from the quasar images farthest from the center of the cluster arrive first. (Quasars are intrinsically variable, and the delay is measured by finding a pattern in the light intensity of one image, and waiting for this same pattern to appear in the others.) The delays seen in SDSS J1004 are 780 days between the 1st and 2nd images; 40 days between 2nd and 3rd; and over 3 years between 3rd and 4th (the 5th image is difficult to see). So your (definitely cool!) idea could work in principle -- just a matter of monitoring one of the images on a regular basis! Christopher: you’re right — we’re seeing each snapshot at a different time, and there are actually two effects that contribute to a time delay between images. First is the one you mention — the length of the path the light travels for each image is different. Second is a general relativistic effect (known as the Shapiro delay) — the different light paths travel through different regions of the gravitational field of the cluster, and the stronger the field, the larger the delay.

The time delay hasn’t been estimated for these images, but it has actually been measured for another cluster lens (SDSS J1004) where there are 5 images of a distant quasar. Here the Shapiro delay dominates over the path length delay, and so the light from the quasar images farthest from the center of the cluster arrive first. (Quasars are intrinsically variable, and the delay is measured by finding a pattern in the light intensity of one image, and waiting for this same pattern to appear in the others.) The delays seen in SDSS J1004 are 780 days between the 1st and 2nd images; 40 days between 2nd and 3rd; and over 3 years between 3rd and 4th (the 5th image is difficult to see). So your (definitely cool!) idea could work in principle — just a matter of monitoring one of the images on a regular basis!

]]> By: Christopher Ak. http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-84809 Christopher Ak. Mon, 20 Jul 2009 18:10:23 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-84809 There is another very neat thing about the different images. Assuming that the deflection of the photons caused them to travel different distances until they got to us, what we are actually seeing is not just distorted views of the same galaxy, but also snapshots at different times! If the difference is big enough - can it/has it been estimated? - and the resolution high enough, I could conceivably see a supernova occur in the oldest snapshots and then focus on the same star in a more recent snapshot. Then I could watch the star and wait until it explodes. How cool is that? Even if the difference is not that great, it would still be very neat to have an 'age' label on each of the views. There is another very neat thing about the different images. Assuming that the deflection of the photons caused them to travel different distances until they got to us, what we are actually seeing is not just distorted views of the same galaxy, but also snapshots at different times! If the difference is big enough – can it/has it been estimated? – and the resolution high enough, I could conceivably see a supernova occur in the oldest snapshots and then focus on the same star in a more recent snapshot. Then I could watch the star and wait until it explodes. How cool is that? Even if the difference is not that great, it would still be very neat to have an ‘age’ label on each of the views.

]]> By: Sili http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-84349 Sili Sun, 19 Jul 2009 17:23:54 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-84349 Thank you, dr Gates. I'm sorry if I seemed to imply any sort of non-rigour. I didn't mean to suggest that there was untoward fiddling going on. I just did wonder how one would go about the practicalities. Cheers! Thank you, dr Gates.

I’m sorry if I seemed to imply any sort of non-rigour. I didn’t mean to suggest that there was untoward fiddling going on. I just did wonder how one would go about the practicalities.

Cheers!

]]> By: Brian137 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/comment-page-1/#comment-83269 Brian137 Fri, 17 Jul 2009 05:10:07 +0000 http://blogs.discovermagazine.com/cosmicvariance/2009/07/13/guest-post-evalyn-gates-on-cosmic-magnification-or-invasion-of-the-giant-blue-space-amoebas/#comment-83269 Evalyn, Gorgeous images, interesting discussion. Thanx. Of course, now I want a pet amoeba. Sean, Occasional guest posts really spice up the site. Good get. Evalyn,
Gorgeous images, interesting discussion. Thanx.
Of course, now I want a pet amoeba.

Sean,
Occasional guest posts really spice up the site. Good get.

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