Posted by jnord 10 hours ago
what makes us so certain that we can trust what we see on James Webb? Can we definitely discard a measurement problem?
For the red dot observations, I believe this things have been measured by at least 3 of the 4 devices on board - NIRCam (near infrared camera, has very limited spectral capabilities through its filter wheel), NIRSpec (near infrared spectrograph) and MIRI (mid infrared instrument).
I cannot pretend to have the actual expertise, but it does seem vanishingly unlikely that all 3 instruments could create consistent artefacts in the same location.
But I'm pretty sure they thought of all of this and many more objections already. It's not like this is a super advanced thread of skepticism that physicists would have overlooked
In Hubble, that fuzz was marked. With Webb, far less so.
I think these are real true positives
We can trust what we see. We can't trust there's nothing where we don't see anything.
I vouched for your two posts in this thread, but that never works, and honestly it gets a little old trying to pick up the slack left by HN's inscrutable, unaccountable, and largely-broken filter. This has been happening a lot lately, unfortunately.
Messing up the data analysis has major precedents. If you aren't familiar you should look into BICEP data in 2014, they thought they had observed primordial gravitational waves which would have been earth shattering. Instead they just messed up the dust correction pipeline. I don't envy the day they came to that realization. I was in several conference rooms at Princeton where BICEP people presented their analysis and David Spergel (of WMAP, previous head of the department at princeton) and others were able to walk them through how they thought they had kind of messed things up. This is what routinely happens, ESPECIALLY when something unexpected is observed. Every possible explanation is looked into, and ESPECIALLY in cosmology, you can do that incredibly well. Cosmology is one of the most beautiful sciences in my experience, precisely because we have such good ways to model the observations to probe various models, and you can treat the observations with Bayesian stats with virtually no risk of misspecifying your model, or, if you do find its misspecified, you have discovered something new about the universe.
The process to go from raw observations to physics, correcting for all the crap in between early universe light and us (dust which also rotates light polarization -- this explained the BICEP issue, instrument systematics which are measured to incredible precision on the ground (e.g. point spread function -- what is the detector response to various intensities of light; e.g. you get electrons for bright sources that spill into neighboring pixels)
Everyone everywhere is looking to make a name for themselves by discovering the discrepancy -- be it a screwup of some other team (astro community is generally very supportive and positive but also competitive) or a problem with simulation assumptions, a genuine discrepancy in our understanding of the universe (i.e. the tension in the hubble constant -- you infer rate of expansion from cosmic background radiation / early universe observations, and then try it using an alternative method -- using local variable stars, and you get a statistically significant difference).
So I would say: if there's a screwup it will be found, and a genuine fuckup is possible and does happen, but when it does believe me we will know usually within a few months. You'll have a ton of people trying to reproduce the results, pouring over everything there is that could possibly explain these observations. The wheel of astrophysics grinds slowly but it grinds finely.
Edit: also shoutout to Jenny Greene -- one of the world's foremost experts on galactic astronomy and also a genuinely great person. She rented me her house for a summer for dirt cheap when I was a poor grad student with nowhere to stay. Also hosted the best graduate student parties (our idea of a party is beer and board games and complaining about our advisers)
Take it with a grain of salt, and know for sure its leaving out a huge range of scientists views.
--1-- Charlotte Mason (not, so far as I can tell, affiliated with or funded by the Simons Foundation)
of the Cosmic Dawn Center (not, so far as I can tell, affiliated with or funded by the Simons Foundation)
which is associated with the Niels Bohr Institute at the University of Copenhagen (not, so far as I can tell, affiliated with or funded by the Simons Foundation, except that the NBI hosts something called the "Niels Bohr International Academy" that has taken money from the Simons Foundation; it doesn't look to me as if Charlotte Mason has any connection with this)
and also with the National Space Institute at the Technical University of Denmark (not, so far as I can tell, affiliated with or funded by the Simons Foundation)
--2-- The James Webb Space Telescope (not, so far as I can tell, affiliated with or funded by the Simons Foundation)
--3-- Jenny Greene (not, so far as I can tell, affiliated with or funded by the Simons Foundation, though she did once give a talk at the Center For Computational Astrophysics at the Flatiron Institute which is part of the Simons Foundation)
of Princeton University (not, so far as I can tell, affiliated with the Simons Foundation though I expect it's taken some of their money, but in any case no one needs an excuse for reporting on work done at Princeton)
--4-- Unnamed-in-the-article researchers who found that a "little red dot" is likely a supermassive black hole without stars around it; the Simons Foundation is not mentioned anywhere in the paper they published about this; neither the first-named author of that paper nor the one quoted in the linked article has obvious Simons connections, and both are at the University of Cambridge which, again, no one needs an excuse for reporting on the doings of.
--5-- Rachel Sommerville of the Flatiron Institute. Here there really is a Simons connection; the Flatiron Institute is part of the Simons Foundation. It does computational research in scientific fields, astrophysics being one of them.
--6-- "a meeting in April 2026 in Helsingør, Denmark" about the early universe; this was titled "Charting Cosmic Dawn in Copenhagen" and so far as I can tell has no Simons connection other than the fact that two of the 21 people listed as "invited speakers and tutorial leads" are from the Flatiron Institute, which seems innocuous since the F.I. does in fact do scientific research in this area.
--7-- Hakim Atek (no Simons connection so far as I can see)
of the Paris Institute of Astrophysics (no Simons connection so far as I can see, though I did find evidence that at least once the Simons Foundation has provided funding for a person working there)
of the Sorbonne University (not affiliated with the Simons Foundation; I'm sure they sometimes take S.F. money but, yet again, this is not an institution that anyone needs excuses to report on the work of)
So, I find one, count 'em, one, instance of a Simons-associated entity in the article. How very sinister of Quanta to mention them and hide their own affiliation. Oh, wait: "Editor’s note: The Flatiron Institute is funded by the Simons Foundation, which also funds this editorially independent magazine. Simons Foundation funding decisions have no influence on our coverage."
You may, of course, choose not to believe that last claim. You might be right. But in this article I don't see any obvious sign of bias; they reported on a whole lot of things most of which have no particular connections with the Simons Foundation, and the one S.F.-affiliated thing they reported on does seem relevant. I can't rule out the possibility that Sommerville's work is actually bad and was reported on here only because of the Simons connection, but e.g. she is one of those invited contributors to that conference in Copenhagen which doesn't seem to have had a Simons connection and does seem to have been run by reputable astrophysicists.
Funding institutions can influence which research gets done, that’s what they do by definition. This can steer people towards and away from various topics or questions, but people will loudly speak their mind if they don’t think something is right. It’s a core tenant of the culture. Go to a colloquia and watch people debate and critique each other.
This subtitle really bothers me. Science isn't about finding out what is true. Science is about finding out what is false and building models to explain the rest. We can never confidently say we know something to be true because that closes the door for future science to disprove our beliefs and that's exactly the purpose of science.
The best we can do is come up with increasingly more useful models accepting that in the end all models are wrong but different models are useful for different purposes.
Science can do a decent job of disproving a hypothesis because even a single contradiction should be enough to suffice in good science, but it's far less efficient at proving anything true even if it seems to always be true. For instance mathematical relationship describing the gravitational attraction between large bodies seemed to always work, but it turns out it was merely a rough approximation that completely fails in various cases such as when one body has a particularly large gravitational pull, or when very high relative velocities are present. And even modern understanding is, at best, another rough approximation because we can already see endless examples in the cosmos of examples that defy current understanding and require further refinements in a direction that's currently unknown.
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Basically at any point in history if you look at the bleeding edge science from a century before, it looks naive in many ways. In each era people always think they have finally moved beyond this, but we never have and it's entirely possible we never will since it's likely this universe has surprises awaiting us that we can't even yet imagine. Think about how utterly bizarre it is that time itself is a relative variable meaning with tech capable of reaching sufficiently high velocities you can literally travel into the future, relative to people at rest (such as all of Earth for example). It's nonsense, but it's completely real.
"True" has a connotation of absoluteness and finality. But I doubt humanity can ever know what is "true" about the universe. We can only model its phenomena with better theories, where "better" is always a temporary badge conferred for its prediction power and degree of agreement with known observations. Until an even "better" theory is figured out.
"Now they just need to figure out which ones are _better_"
But what about the why? Why do we seek ever more predictive models? Obviously more predictive models allow us to just... do more and better things. And I think it's fair to say that that's enough justification in itself. But is there no substance behind the idea that we seek ever more predictive models because we believe it to be a (perhaps the only) systemic way towards "the truth"?
Put in other words, do you actually believe that there is no room for truth in science? Just concurrence and agreement with observation?
I guess I'm just nitpicking on your use of the phrase "science is about". I do agree that perhaps a better subtitle (without needing to reach for contortions in language) would be "which ones are more true".
The data found doesn't contradict the big bang in any shape or form. It does challenge beliefs around black hole formation.
The reason for the big bang model is because based on all our measurements of all the visible universe, it appears that everything is spreading out. Any new model needs to explain why it is the universe appears to be spreading out.
There's not a scientist alive that wouldn't like to discover that "actually a fundamental principle about my field of study is completely wrong". But that takes hard work, evidence, and models which better fit than the previous ones did. You need to find something that can't be explained with the old model and can only be explained with the new model.