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https://twitter.com/alex_parker/status/1116070667068170240?s...
JWST will have smaller “pixels” but is in the same ballpark.
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Quantum Physics and General Relativity make different predictions in specific circumstances which are beyond our ability to test to figure out which one is wrong. They can't both be perfectly correct. But in every test we can make, both seem to model reality really well. The best place to look for new data where we might find reality disagreeing with either model is in the extreme parts of the universe, like black ho…
Relatedly, before general relativity, people already knew something was wrong with Newton's theory of gravity from observing the orbit of Mercury, which didn't follow the theory accurately. At that time Mercury, being so close to the Sun, was an extreme condition that showed the flaws in the theory. The fact that general relativity continues to hold up to every observation we can make is remarkable.
Granted, I only ever got as far as E&M physics in college so I could be way off here but that scenario has turned up so many times in history.
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Gravitational physicist here. Every time we look in a new place and see that GR still works, it is pretty amazing. Part of this is the fact that everyone in the field works very hard to find a crack in GR's armor, and so far it has resisted everyone. The other part is that GR has a romantic beauty to it, both in structure and in predictions. Each time GR matches reality in a new context, the feeling is akin to watchi…
It seems the common expectation is that GR is more likely to be the theory that needs to be modified the most - or more or less tossed out and replaced with a quantum theory of gravity. Is it possible that GR is just "right" and QM needs to be modified to fit into it?
That said, the mathematical fundamentals of GR do not directly incorporate notions of the uncertainty principle. That fact alone, I believe, means that GR is an incomplete description of space/time/physics.
I thought it was Sagittarius A* back then.
I find the whole thing amazing and captivating - yet the image is … huh … slightly underwhelming. It looks like some gaussian blurred random image. I wish it could be the kind of crisp image JWST ‘sent’. It’s difficult to force oneself to not romanticise these un-visible things based on artists visualisation we got accustomed to.
It reminds me of all the hype and exuberance around the "first ever picture of a black hole". An achievement worthy of being lauded, for sure, but something just felt so artificial about the coverage. And truth be told, the photo itself was underwhelming in light of how incredible it was made out to be.
>Although we cannot see the black hole itself, because it is completely dark
I recall the EHT imaging 2 objects back in 2019 - M87 and another black hole. Does anyone remember what that was, or am I mistaken? I thought it was Sagittarius A* back then.
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Just curious but why?
They want an exciting disruption to current theory.
Black holes are a solution to the general relativity equations, but Einstein thought they were just a mathematical quirk, and that in real life, they wouldn't have been able to form.
So ever time someone says "Einstein was right" when talking about black holes, then no. He was right about general relativity, but he was wrong about the existence of black holes.
I recall the EHT imaging 2 objects back in 2019 - M87 and another black hole. Does anyone remember what that was, or am I mistaken? I thought it was Sagittarius A* back then.
They collected data on both back in 2017. It took until now to develop the image processing techniques to account for the rapid changes in the accretion disk around Sag.A*.
> “We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity," And ten thousand physicists sighed disappointingly.
Gravitational physicist here. Every time we look in a new place and see that GR still works, it is pretty amazing. Part of this is the fact that everyone in the field works very hard to find a crack in GR's armor, and so far it has resisted everyone. The other part is that GR has a romantic beauty to it, both in structure and in predictions. Each time GR matches reality in a new context, the feeling is akin to watchi…
That's beautifully worded. It brings up the respect scientists can have for one another's work (in the best case scenarii, let's skip the bad seeds for a moment).