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Universe Is Expanding Faster Than We Thought (gizmodo.com)
An anonymous reader writes from a report via Gizmodo: The Hubble Space Telescope has released some new numbers indicating that the rate of expansion of our universe is approximately 45.5 miles per second per megaparsec. It calculated this by measuring the distance between 19 faraway galaxies. Conceptually, the calculations show that space is expanding fast enough to essentially double the distance between our galaxy and our nearest neighbors in about 10 billion years. The new Hubble constant, which is 5 to 9 percent higher than previous estimates, does not match estimated expansion rates from the energetic leftovers of the Big Bang, thus causing a headache for cosmologists. It could mean that Einstein's theory of relativity is incomplete and/or there are processes pushing space apart that we have yet to account for.
It could mean that time is a lot different than current physics accounts for.
The new Hubble constant...does not match estimated expansion rates from the energetic leftovers of the Big Bang, thus causing a headache for cosmologists.
I thought the real headache for cosmologists was that the measured value of the cosmological constant, which is what powers the accelerating expansion, was ~120 orders of magnitude different from the best calculations. If I have understood it correctly then this new result seems to suggest that the cosmological constant is not in fact a constant. So given that we clearly have absolutely no idea what is driving the expansion of the universe I don't see this new information as a headache but rather as clue which should help solve the puzzle of dark energy.
That joke soon to be illegal California
http://www.washingtontimes.com...
I wish slashdot headlines weren't so definite. This is a single paper adding incrementally to our knowledge; it is not a survey article describing the joint understanding of all cosmologists.
For example, reading the paper, the galaxies hosting the supernovae in the sample had Cepheid--calibrated distances, in other words these are reasonably close objects (hence the reference to the local Hubble constant). While the paper discusses the possible effect of local motions of these 19 (!) galaxies, I don't think this discussion is sufficient. These proper motions are a more likely effect than issues with the CMB.
Truth is unobtainable. Worth a try though.
My personal motto is "fortasse desperato sed conor nihilominus", which is Latin for "it may be hopeless but I'm trying anyway", and that is the foundational principle of my philosophy, both in the "attitude toward life" sense and, back on topic, in the academic sense: from that principle, stated a bit more formally, I build up to a formulation of the scientific method, where you can never quite reach the truth but you can get a lot closer by trying than you would by giving up, whether that be giving up in the sense of abandoning any hope of success (nihilism, which all forms of relativism boil down to) or falsely claiming you've already succeeded (fideism, encompassing in it any appeal to authority or the supernatural, i.e. religion); and I also, separately, build from that foundational principle to an ethical analogue of the scientific method, but that's off-topic here.
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
I would suggest that there's something in the middle.
1) Theories typically have to start off as wild assed hypotheses plucked from somewhere. I know of a group of highly published physicists who sit around passing a joint giggling and coming up with theories which they investigate further once they sober up a bit. Thinking outside of the box to find answers often requires creativity... especially when the theory is completely unable to be observed.
2) Due to obvious lack of observed information, new theories are often published citing other theories as their foundation. This is amazing because it can help prove the original theory by providing a possible application. It's very little different than smoking the joint and giggling over "what if...?". It's a necessary step to allow peers to collaborate. Publishing for peer review does not actually mean "I believe I'm indisputably correct, bow to me or prove me wrong". It's a method of sharing information so other people can try and run with it too. There are too frigging many people (especially journalists... even "educated" journalists) who seem to believe papers publish for peer review are proofs. Or worse, because of this stupid religion vs. science debate, there are people "representing science" who are trying to explain "The theory of evolution" to idiots running museums displaying humans riding dinosaurs and misrepresenting the word "Theory" to make it sound like "As good as fact".
3) There are good scientists who work for a living and try to establish a foundation for their theories before simply grabbing 5 papers written by others, gluing them together like a collage and spamming them into the first journal to take them. These guys will actually put some effort into it, visit the local university and peer review with students, professors, etc... and eventually after believing they've reached a point of reasonable certainty that their theory isn't simply shit, they'll release the paper to be torn apart by a group of people who will like the idea and try to run with it, like the idea and try to disprove it as a favor to the author, or others who will try to disprove the idea using nothing but a crayon and a napkin because they're dicks.
4) There are bad scientists who somehow manage to establish published bibliographies that span multiple pages. Some of these guys are people who got their Ph.D., "mentored" shit loads of grad students and put his name first on the paper. What's worse is that he also made the student pay to get it published. Even worse is that he didn't put his name on other papers that he should have. Even worse, he didn't even really read the paper he put his name on, he simply said "He looks pretty smart... If I take credit for his work, I won't likely get burned". That scientist, when he eventually publishes his own work likely doesn't have 2 grams of originality. What's worse is that since he's such an amazingly highly published scientist with so many good papers under his belt, the journalists will flock to his paper.
Science and the scientific process is not flawless and has to be constantly improved on. I obviously represented it terribly here and that was because I'm playing devil's advocate. I hold science in incredibly high regard and respect. I spent two years of my life helping scientists and mathematicians translate from Ph.D. to human for the purpose of publishing papers or patents. I learned more by doing that then I could in a hundred years of reading. I believe part of the scientific process that works well is the hecklers and the critics. They're like the fellow who would stand behind the roman general upon his chariot while entering Rome whose job it was was to whisper "You're not a god" as a reminder.
I think you misunderstood my point; I was arguing against the "pulled out of their asses" notion of the person I responded to by pointing out that all of science is just increasingly more-educated guesses, and that's fine and normal and couldn't possibly be any other way. Finding that the universe was accelerating was the less-wrong conclusion that supplanted the assumption that it was decelerating, previously jumped to for insufficient reason; not that the reason being insufficient is a criticism, because no reason can ever be sufficient, so we've got to settle for "good enough for now" and expect to find out we were wrong in some ways later.
This newest result is just finding out one of the ways were were still wrong after that. And no doubt the new conclusion is also still wrong. But they're getting less wrong, and that's the best we could possibly hope for.
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
Today's understanding of the universe will probably be ridiculed in the future and get compared to when everyone accepted that the world was flat or that the Sun orbited the Earth.
The relativity of wrong - Issac Asimov's reply to that old canard.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
"double the distance between our galaxy and our nearest neighbors in about 10 billion years." - except we won't, because the two galaxies are gravitationally bound and the bond overcomes space expansion.
It only works between superclusters of galaxies.
The analogy of "dots on expanding balloon" is inaccurate. It's more like blotches of dried, hard glue - each blotch being a supercluster. The space expands in between them, they drift apart, but each blotch remains roughly the same size.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2