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Archive link using a tool I built to automatically redirect to archive links :)
https://unbloq.us/https://www.theatlantic.com/science/archiv...
archive.is already has a redirector btw:
https://archive.is/timegate/https://www.theatlantic.com/scie...
Wow this is really great
Thank you! Glad people are finding it useful :)
Archive link: https://archive.is/51R4k
Reminded me of this thread from a couple of days ago. Interesting that both Riess and Gough argue there's a sociological phenomenon amongst cosmologists. Though who knows what Riess might think of the "blowtorch theory." https://news.ycombinator.com/item?id=44115973
I have a phd in astronomy and I spent some time reading it yesterday. I don't think he'd think much of it. The theory seems to be aimed at explaining the existence of cosmic voids and the structure of the cosmic web. But these are pretty naturally explained by lambda CDM. And if the goal is to explain away dark matter, there are other pieces of evidence for dark matter that wouldn't be explained by this theory. At any rate, as far as I can tell it's not a quantitative theory so it would be hard to tie it to observations.
Interesting thanks!
Every scientist knows there is a sociological component to the practice of science. This is not a novel or noteworthy observation and I don’t think Riess was intending it to be.
Also, every cosmologist knows the standard model is not the final answer. I think the author is really trying to overstate the controversy.
I happen to not be a scientist but found the observation interesting given the overlapping subject matter. Especially given the stark differences in training/background. E.g. scientist/not scientist.
> For nearly a century, astronomers have known that the universe is expanding, because the galaxies that we can see around us through telescopes are all rushing away. Riess studied how they moved. He very carefully measured the distance of each one from Earth, and when all the data came together, in 1998, the results surprised him. They were “shocking even,” he told his colleagues in a flustered email that he sent on the eve of his honeymoon. A striking relationship had emerged: The farther away that galaxies were, the faster they were receding. This “immediately suggested a profound conclusion,” he said in his Nobel Prize lecture. Something is causing the expansion of the universe to accelerate.
I'm quite confused by this early paragraph. It seems to be claiming that Hubble's law was discovered in 1998 by Adam Riess, instead of in the 1920s by Edwin Hubble (and others).
It's the second derivative.
Riess et al's findings showed that galaxies farther away are not just receding faster (as Hubble's Law already described), but that the rate of expansion itself is increasing over time. This discovery suggested the presence of a mysterious force, now called dark energy, driving this acceleration.
This was unexpected because most astronomers at the time thought the expansion should be slowing down due to gravitational attraction between galaxies.
Yes, but the article is indeed unclear about this. In particular this line:
>The farther away that galaxies were, the faster they were receding.
This is already the case in Hubble's law, which says that the velocity is proportional to the distance. Hubble's constant is the proportionality constant and thus the expansion rate.
Riess found that the Hubble constant is not constant. Instead, the expansion rate is increasing over time.
>but that the rate of expansion itself is increasing over time.
Take for example galaxies running from us at "c". They happen to be exactly at 13.7B light years - coincidence? I don't think it is a coincidence, and some simple logic leads to conclusion that the same galaxies will be running from us at the same "c" say 300M years later - ie. then it will be "c" at 14B light years distance from us - which means that the Hubble constant is actually decreasing.
But further away galaxies are further back in time, so if the expansion is accelerating.. shouldn't they be going away at a slower speed, and the closer galaxies going away from us at a faster speed?
I think they're talking acceleration, not velocity? Hubble's law says more distant galaxies are receding faster than slower ones at some calculable rate, but it doesn't say the rate at which they're doing that is accelerating over time. (I do find it kind of shocking that one can prove this without observing the same thing over a prolonged period of time.)
Disclaimer that I'm not an astronomer and might be totally wrong, but from some quick searching, it seems like the article is conflating Hubble's discovery and Riess's. Hubble's law can be true even if the expansion of the universe is slowing down, not speeding up: a galaxy twice as far away as another can be receding at twice the speed, even if that speed is decreasing over time. But it seems like Riess's discovery is that the speed is actually increasing over time. It's related to Hubble's law but not the same thing.
Frankly, the fact that I could find that out with 2 minutes of reading Wikipedia reflects pretty poorly on the author.
The Hubble Tension is not Hubble's constant.
Adam Riess might be right, but for reasons he won‘t like. Much of his measurements (and also his Noble prize) depend on the supernovae 1a, which according to the standard model are standard candles. That means it is assumed they always reach the same luminosity, so they can be used to measure distances in the universe (the fainter they are, the farther away they are).
However what if supernovae 1a are not standard candles and their luminosity varies over a much greater range? Then a lot of distance measurements from Riess et. al. are wrong. I belief that scenario to have higher probability than many of the proposed alternatives. But Riess cannot see that, because it would put into question his lifes work.
I guess they've watched the expansion between two galaxies over time and found it increasing?
Otherwise, the fact that "the further away from us they are, they faster they were receding" made me think of this way:
-the further away they are, the longer the light had to travel to get here
-the longer the light had to travel, the longer it took to get to us
-the longer it took to get to us, the further into the past we are looking
-the further into the past we look (further distances), the faster they are receding - doesn't that imply it was faster in the past? The further past we look, the faster it is. The closer we look to home (the closer to "now"), the slower it is.
Galaxies farther away are receding faster because they are older. What Riess found is that it isn't linear with distance, they are moving away at an accelerating rate. I assume this shows up with close galaxies moving faster than they should.
The acceleration was really fast after Big Bang, but slowed down. It was assumed that it would flatten out and expand at constant rate.
I wish the journalist asked the leading scientists in the field “Before you learned of the Hubble tension, what did you think the odds were of the standard model being correct? And after?”
And everything would be much clearer.
I think it's still not universal among astronomers that the Hubble tension is real. (Though the tide seems to have shifted in the last two years or so with the median astronomer reluctantly accepting that the Hubble tension is probably real.)
All of this is wildly exciting - I wonder if this is how people in the 1800s and 1930s felt like, as electricity and nuclear science was going through its hey-day.
Your time's a bit off - electrification didn't really take off until the early 20th century and nuclear applications outside of weapons until the 1950s and 1960s.
My grandmother grew up when cars were scarce, electric wires were stapled to the wall, and indoor plumbing was for city folk. She hit a certain level of technological advancement and then just stopped, probably around the 1980s. She died last year, having never used the Internet or a computer and still using a console TV (with an adapter box installed by the cable company).
The description of how the universe is expanding sounds like how an explosion expands. Rapidly then slower until it settles down and stops (with no collapse at the end, just matter in place where it landed). I wonder if that could be the closest analogy?
An explosion has a center. I'm not a cosmologist, but my understanding is that the universe expands everywhere and at a rate that's in fact accelerating rather than slowing down.
What does the has a center comment have to do with the rest of the comment? The big bang had a center too. That doesn't mean anything in the context though.
Riess' original discovery is the opposite: The universe expands faster and faster over time.
Is there any succinct publication of his observations?
There's a "general audience" review by the man himself.
Very well written.
I felt like reading a good novel.
I'm not an astrophysicists, but dark energy and dark matter have always felt like "fudge factors" to me.
Paywall bypassed:
> He compared the theory to an egg that is breaking. “It’s not going to cleave neatly in one place,” he said. “You would expect to see multiple cracks opening up.”
Someone needs to send him an https://en.wiktionary.org/wiki/Eierschalensollbruchstellenve...
interesting was trying to figure out how it works looks like the metal bead you raise and drop it
“It is easier for a cannibal to enter the Kingdom of Heaven through the eye of a rich man's needle than it is for any other foreigner to read the terrible German script.”
Mark Twain
They may certainly have a point, but many Nobel Prize winners do have a track record of going off the deep end which is something to keep in mind when an article tries to justify their points using Noble Prizes
edit: I'm just trying to say that "Having a Nobel Prize" doesn't mean they are an authority on subjects they talk about since many wen't on to promote homeopathy, aliens, believed aids wasn't caused by HIV, don't believe in climate change, etc."
https://en.wikipedia.org/wiki/Nobel_disease
This is a decently-well documented observation. (I hesitate to call it a "phenomenon" as that would imply an actual casual mechanism.)
Reminds me of Roger Penrose more recently. When Nobel Prize winners start making YouTube rounds, you have a good indicator of someone going of the deep end. Thank God, Eric Weinstein doesn't have a Nobel Prize...
If even getting a Nobel Prize isn't enough to protect someone from being accused of deviating from orthodoxy and therefore ipso facto "off the deep end", then the entire claim the science apparatus makes about being all about ideas and not about orthodoxy is falsified, and all subsequent beliefs in a belief net based on that proposition need to be updated accordingly.
Eh, I think that is just the result of more attention/funding. Plenty of scientists have wacky ideas (very much encouraged!) that do not pan out upon further investigation. If you are a no name lab that tries a novel idea that fails, nobody knows or cares. “Celebrity” scientist with a failed idea and now you are off the deep end.
Is there a correlation between being born in Superfund sites and being a Nobel Prize winner?
The blaming of cliques of scientists for rejecting alternate ideas was cliche and kind of a red flag.
That does happen, of course. Science is conservative because if we have a theory that is a good fit to the data it should take a lot of evidence to unseat that theory and the new one must also fit all the data the old one did. (Unless some data was wrong, but that also takes evidence.)
But this is also something every crank says, and loudly. The more obsessed and loud someone is with a conspiracy against them the more they sound like a crank.
Was Einstein or quantum theory instantly rejected and held down forever by a conspiracy? Not really. There were skeptics but I seem to recall these ideas taking hold pretty fast because they fit a lot of anomalous data very well.