MONSTER GALAXY spotted hiding behind IMMENSE BLACK HOLE Astro-boffins have detailed a "monstrous" galaxy near the edge of the charted universe, and have done so to an unprecedented degree of detail using the Atacama Large Millimetre/submillimetre Array (ALMA), with the assistance of a natural telescopic phenomenon known as a gravitational lens. According to the National Institutes …
the image is compressed spatially by the gravity of the super-massive black hole, so appears crisp, and it shows a galaxy churning out stars at a rate many times that of our own... but has anyone corrected for any temporal compression that may have occurred as a result of a lensing effect known to affect both space and time? I mean, this isn't my field, so I'm just thinking out loud here...
How about "self-maintaining thermodynamic disequilibrium"
Not really accurate. Life exists on Earth because the biosphere is under a net inflow of energy. The thermodynamic gradient isn't "self-maintaining" - it's maintained by the big ball of plasma in the sky, radioactive decay in the ground, residual energy from the planet's warm mantle and spinning core, and a few other less-important sources.
Where such an inflow exists, there must be increasing complexity to dissipate the gradient. The resulting structures might take a form that some group of judges (take your pick: biologists, philosophers, people in general...) would call "life" or "lifelike". For most observers there's probably some stage of complexity where they'd say, yeah, that's life. But the criteria will differ from person to person.
"SDP.81 is an enormous galaxy" should really be "SDP.81 was an enormous galaxy 11.7 billion ago".
For most purposes the distinction is meaningless. Simultaneity over distances where C is a dominating factor has no useful meaning: if no event "there" can have any effect "here" for 11.7 by, then whether something there happened 11.7 bya rather than "now" has no material consequences. It's sometimes an important point when considering the consistency of the physical model (for example, to keep causality intact in that model), but generally it's just a philosophical fillip.
"I would guess that any temporal effect there might be on a photon when it zips past a 100,000ly galaxy..."
AFAIK photons don't experience time. It's all now for photons - emitted and absorbed at the same instant even if billions of light years separate emitter and absorber. Google it. Strange place this universe.
Looking at the photo, I couldn't help noticing that there are *two* identical rings - I expect the scientists failed to spot the second one in their excitement. And judging by the scale shown on that image, the two rings are about 6 inches across, so I guess anything that is 6 inches can be described as being a galactic size ...
I've asked this before but did not get a definitive answer.
ALMA has 66 dishes. Is that image composed of 66 pixels or does each dish scan a tiny piece of sky to increase the resolution?
I find it hard to believe that a dish could be aimed so accurately.
I looked here but it did not enlighten me.
https://en.wikipedia.org/wiki/Atacama_Large_Millimeter_Array
In astronomy the resolution is called resolving power and is dependent not on the number of pixels of your sensor (which is a radio antenna) but on the diameter of your telescope relative to the wavelength you are observing and the funny thing is an array of telescopes can be treated as one big telescope. They all look at the same patch of sky and some fancy electronics/computing does the aiming/image reconstruction. Look up Inteferometry.
(Not sure if that's a sincere question or a joke...)
By definition, we're exactly in the middle of our Hubble Volume, which is the same as the knowable universe. Whatever we find out about the knowable universe becomes part of the "known universe".
And nothing we do can ever have an effect outside our Hubble Volume, so "knowable universe" is a suitable proxy for "entire universe" for nearly all purposes.
That's one possible answer to the question of "where are we in the universe"?
Another interpretation is "given what we believe we know about the universe, or think is the most plausible among various theories, how are we situated among much-larger-scale structures"? I don't really follow the field, but the latest I've seen is that the Milky Way is part of a galactic supercluster astrophysicists call "Laniakea", which is really quite large, and that is part of a larger arrangement of superclusters that's so big that "where are we inside it" isn't meaningful.
30 milli-arcsecond resolution of 1mm wavelengths is very impressive. That's better that Hubble's highest resolution, as I understand it, and of course Hubble has no instruments that can see at 1mm wavelengths.
In effect, the closer elliptical galaxy is the objective lens of a really big refracting telescope, and ALMA is the eyepiece. Too bad we can't point it in a different direction.
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