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At 9:00 AM Eastern Daylight time, tomorrow, Wednesday, April 10, scientists will hold simultaneous news conferences in Washington, DC, Belgium, Denmark, Chile, Japan, China, and Taiwan to reveal the long-awaited results of the Event Horizon Telescope. It will be very interesting to see the results.
It is things like this, the Event Horizon Telescope, as well as other like endeavors, that we should be spending our funds on. Trump's idea of returning to the moon is a waste of time, money and talent. We've done that and should be moving on to more intriguing things like Mars on the one hand and a greater understanding of quantum mechanics on the other.
Bill
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And the end of the fight is a tombstone white, With the name of the late deceased, And the epitaph drear, "A fool lies here, Who tried to hustle the East."
In anticipation of later on today, here's a pretty good video:
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"Anything you do can be fixed. What you cannot fix is the perfection of a blank page. What you cannot fix is that pristine, unsullied whiteness of a screen or a page with nothing on it—because there’s nothing there to fix."
No Sagittarius A because she is not feeding like M87 was I guess, but he said they are working on it. They said 7 years ago this thing wouldn’t look so photogenic, cuz it was spitting out blobs of plasma back then, part of that massive jet stream.
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Great posting the photos, Ricardo. What a testament to man's intellectual and technical ability to begin to really understand the universe, both at the macro level (cosmology) and the micro level (quantum mechanics). This is one big step among many, but it is huge.
Below are a couple of quotes from the website ARS Technica.
"At a press conference this morning, Avery Broderick of the Perimeter Institute described what the images tell us. One key finding is that the object is a black hole, at least as we've understood black holes using relativity. It does not have any visible surface, and the "shadow" of light it creates is circular within the limits of our observations. We can also tell that it spins clockwise. All of the properties we can infer from these images are consistent with relativity. "I was a little stunned that it matched the predictions we made so well," said Broderick.
"The University of Amsterdam's Sera Markoff said that the size of the black hole provided a new estimate of its mass; she called it "really a monster, even by black hole standards." It's roughly the size of the Solar System, but has a mass that's 6.5 billion times that of our Sun. This actually resolved a conflict between two other measures of its mass, one from the motion of gas clouds nearby, the other from tracking the stars orbiting it. This may help us refine estimates of mass for black holes elsewhere."
Great stuff.
Bill
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And the end of the fight is a tombstone white, With the name of the late deceased, And the epitaph drear, "A fool lies here, Who tried to hustle the East."
What kind of timeline would be presented with the emulated movements in the first .gif? -
In another forum someone said hopefully this would contribute to (perceived) shrinking of the problems on earth, to which I posted an excerpt from a dialog with a fictive AI-consciousness. -Named Olga, that I mentioned here before. (Whichs content again, I suppose no one here would like to ponder about.)
Another poster said how fascinating it was to see what can be gained when international scientifical means are bundled up.
To which me fully agrees. May such swiftly come about for imminently relevant matters on this tiny planet, 55 mill. light years off the scene.
PS: reading up on it, it seems that the first "accurate" visual representation of a black hole (horizon event, you know what I mean!) goes back to the work of Jean-Pierre Luminet (published in La Recherche and Astronomy and Astrophysics in 1979) using a punch-card IBM 7040 (see last page): http://adsabs.harvard.edu/full/1979A%26A....75..228L 40 years later and we finally have the real thing!
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"Anything you do can be fixed. What you cannot fix is the perfection of a blank page. What you cannot fix is that pristine, unsullied whiteness of a screen or a page with nothing on it—because there’s nothing there to fix."
Today, 29 May 2019, marks the one hundredth anniversary of the solar eclipse that provided direct evidence of Einstein's theory of gravity laid out in his General Theory of Relativity. It confirmed that gravity was not a force acting independently across a passive space, but was a function of the warp and curvature of space-time itself.
Walter Isaacson, in his biography of Einstein, recounts an exchange between Einstein and a graduate student, Ilse Schneider, when news came that the theory had been confirmed. Schneider recalled later that at the time she asked Einstein what he would have thought if the eclipse observation had contradicted his theory. Einstein replied, "Then I would have been sorry for the dear Lord, because the theory is correct."
Bill
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And the end of the fight is a tombstone white, With the name of the late deceased, And the epitaph drear, "A fool lies here, Who tried to hustle the East."
Today, 29 May 2019, marks the one hundredth anniversary of the solar eclipse that provided direct evidence of Einstein's theory of gravity laid out in his General Theory of Relativity. It confirmed that gravity was not a force acting independently across a passive space, but was a function of the warp and curvature of space-time itself.
Walter Isaacson, in his biography of Einstein, recounts an exchange between Einstein and a graduate student, Ilse Schneider, when news came that the theory had been confirmed. Schneider recalled later that at the time she asked Einstein what he would have thought if the eclipse observation had contradicted his theory. Einstein replied, "Then I would have been sorry for the dear Lord, because the theory is correct."
Bill
I often come across the topic of grand unification.... referring to running the cosmic movie backward in time such that in the earliest moments after the Big Bang event, the 4 known “forces” recouple together and appear to be a single force. This apparently works neatly for strong nuclear force, the weak force, and the electromagnetic force....but the comparative weakness of gravity makes it stand off from the others. Theorists looking for clues focus on the need for forces to use bosons to exchange force info between locations (gluons for atomic nucleus, W and Z for weak interaction, photons for electromagnetism), so they hope that a discovery of a ”graviton particle”, might lead us toward unification if the thing can fit into the standard model framework.
But it always confused me why they need to do this at all if GR reveals gravity to be a curvature of space response to presence of massive objects, rather than a “force”. If the sun disappeared magically, spacetime snaps back flat with a wave that propagates at the speed of light, no need or even time for gravitons to be exchanged in some way to make this happen. Earth orbit changes instantly as we see the sun blink out 8 minutes after the last emitted photon reaches us because the gravity wave hits us at the same precise moment So unless I am miss understanding the supposed graviton interaction (I am sure I am), I don’t see a point to trying to unify gravity at all. If anybody could explain it clearly that would be great! Meanwhile I believe the dark matter problem and this unification problem to be directly related (the reason both are elusive is due to the same misunderstanding about GR).
I know exactly what you mean. This same exact question has been bothering me for some time. It never seems to get addressed in the popular books or talks I listen to in enough detail. But I THINK I have some idea about why the Graviton “has to” exist... and that is because of Quantum Field Theory. If you make the other forces like Electromagnetism a field that lives in space, and you must quantize that force, then the logic follows that space itself gets quantized too in the process. Now everything in the world must happen in discrete chunks of vomit soup. This of course caused all kinds of issues in the process like vacuum energy discrepancies that have to be normalized and how to deal with gravity.
If space is quantized and the sun were to be blown up by aliens then the gravitational wave would propagate like a series of graviton dominos, because space is not a continuous medium according to QFT.
Dark matter was thought to be a possible GR/gravity problem but now there is enough evidence that points to it being a particle. Those that still hang on to GR have to alter the rules so much that it falls apart in other basic areas.
I'm sticking to this thread for all space-related news:
looks like we're going back to Titan. The previous probe, Huygens (ESA), was designed to emit data only during descent and for a very short while on the surface (if memory serves it sent data for just an hour or two after landing). The new probe, Dragonfly, will spend two years on the surface and, unlike the Mars rovers, it will be flying around instead of rolling around. It'll be another 15 years before it gets there though (launch in 2026, arrival in 2034).
"Anything you do can be fixed. What you cannot fix is the perfection of a blank page. What you cannot fix is that pristine, unsullied whiteness of a screen or a page with nothing on it—because there’s nothing there to fix."
The Nobel Prize for physics was announced today and was shared by three physicists for work on black holes.
From the Washington Post:
"An American astrophysicist, Andrea Ghez, was among three scientists awarded the Nobel Prize in physics on Tuesday for her role in discovering a supermassive black hole at the center of our galaxy. Ghez, 55, shared the honor with German astrophysicist Reinhard Genzel, who was also cited for his work on the galactic black hole, and with Roger Penrose, a British mathematical physicist cited for his discovery that Albert Einstein’s theory of general relativity predicts the formation of black holes."
Bill
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And the end of the fight is a tombstone white, With the name of the late deceased, And the epitaph drear, "A fool lies here, Who tried to hustle the East."
The Nobel Prize for physics was announced today and was shared by three physicists for work on black holes.
From the Washington Post:
"An American astrophysicist, Andrea Ghez, was among three scientists awarded the Nobel Prize in physics on Tuesday for her role in discovering a supermassive black hole at the center of our galaxy. Ghez, 55, shared the honor with German astrophysicist Reinhard Genzel, who was also cited for his work on the galactic black hole, and with Roger Penrose, a British mathematical physicist cited for his discovery that Albert Einstein’s theory of general relativity predicts the formation of black holes."
Bill
Here is a nice long discussion that relates both to his prize and other topics discussed in this long thread. Enjoy, it’s great!
Any thoughts on what the change of administration might mean for NASA programmes? Trump had put Artemis front and centre and pushed for the date of the next manned mission to the lunar surface to be moved up to 2024. But I don't think NASA got the kind of funding it needed to make that kind of rapid progress possible (if it was even possible to begin with).
My guess is that under Biden the focus will shift towards Earth Science, given its importance for things like climate change. Which might mean pushing back the schedule for other programmes, like Artemis. That might be wise of course, but as someone who wasn't alive during any of the manned missions to the lunar surface, I'll admit that I'm quite eager for them to do it. I guess pushing it back would also make sense since they could then align it with the schedule for delivery of the lunar gateway (2028). Though even for that I don't know how reliable the schedule is. CSA, JAXA and ESA are still on board, but Roscosmos announced just a few days ago that they were withdrawing. At least, they're no longer sending any reps to the expert group. But maybe that's just a bargaining tactic, a bit of political pressure to see if they can get more out of it now that the US is changing leadership.
but as someone who wasn't alive during any of the manned missions to the lunar surface, I'll admit that I'm quite eager for them to do it.
You (and others) have probably seen this, but just in case if not: this is a real-time recreation of the first Moon landing mission - the Apollo11 in July 1969: https://apolloinrealtime.org/11/ (all the buttons can be interacted with, switching between different comms channels or data sensors etc.)
Immersing oneself in it turned out to be quite moving. I mean, while we wait for the real thing to happen again..
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Just came across this, an image of the same black hole. The data has been processed to display the polarization of the light in the surrounding halo, which depicts the magnetic field around the black hole.
Very impressive image. Thanks for sharing this, Richard.
Bill
_____________________________
And the end of the fight is a tombstone white, With the name of the late deceased, And the epitaph drear, "A fool lies here, Who tried to hustle the East."
Here is a nice long discussion that relates both to his prize and other topics discussed in this long thread.
One of the things that amused me about this was that both Greene and Penrose were clearly disconcerted momentarily by the other’s pronunciation of the surname of Karl Schwarzschild
Here is a nice long discussion that relates both to his prize and other topics discussed in this long thread.
One of the things that amused me about this was that both Greene and Penrose were clearly disconcerted momentarily by the other’s pronunciation of the surname of Karl Schwarzschild
My favorite part was toward the end when he admitted he submitted some papers last year (2:03:50) that were totally destroying inflation models and has been waiting for the blowback but so far....crickets.
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