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Mystery of the Coldest Spot In the CMB Solved
StartsWithABang writes: The cosmic microwave background is a thing of beauty, as not only does its uniform, cold temperature reveal a hot, dense past that began with the hot Big Bang, but its fluctuations reveal a pattern of overdensities and underdensities in the very early stages of the Universe. It's fluctuations just like these that give rise to the stars, galaxies, groups and clusters that exist today, as well as the voids in the vast cosmic web. But effects at the surface of last scattering are not the only ones that affect the CMB's temperature; if we want to make sure we've got an accurate map of what the Universe was born with, we have to take everything into account, including the effects of matter as it gravitationally grows and shrinks. As we do exactly this, we find ourselves discovering the causes behind the biggest anomalies in the sky, and it turns out that the standard cosmological model can explain it all.
Isn't the whole point of this area is that is anomalous? at least in comparison to all the other areas of the CMB? yes there are other 'cooler' areas but this seems to be the only one of this magnitude. If this was a common feature across the whole CMB then the cold spot could be considered as part of the standard cosmological model surely?
Aw, boring. I was hoping that everyone was wrong and we get some new physics. Misconception of scientists number one, scientists (and me) like to be shown wrong so we can go and investigate and discover new knowledge. The day it turns out that we know everything will be a very sad day indeed.
http://www.mueller-public.de - My site http://www.anr-institute.com/ - Advanced Natural Research Institute
Before the void was found, a cold spot that large should have been rare enough that it seemed odd we had even one in our sky. With the void explanation it's no longer rare enough in the models that it seems odd we have one.
Something can be uniform and fluctuating at the same time. All that's required is that the fluctuations follow the same, regular pattern everywhere. I have no idea whether this is true for the CMB, however.
It is true. Further, the fluctuations are tiny - at the parts per million level. It took 28 years after the CMB was discovered to detect any fluctations at all, requiring a sophisticated space probe (COBE) to do it.
Asserting that the CMB is "not uniform" because of these fluctuations is rather like saying the Bonneville Salt Flats are not really flat at all since the surface has millimeter scale irregularities, or your polished marble dining room floor isn't flat since it has micron sized irregularities.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
That cold spot will require a big salt ring.
How will we know that we know everything?
If we can't observe anything new. And by "new" I mean something that was not predicted by a scientific theory. Of course, there is always the possibility to observe something new, but it's like an asymptote. New scientists will be less and less excited, because they will just confirm established theories.
http://www.mueller-public.de - My site http://www.anr-institute.com/ - Advanced Natural Research Institute
Inflation was cooked up to explain most of that after the fact, though, so it's unsurprising that it does. The fundamental problem with inflation is that too much is tunable. Penrose's cyclic cosmology explains all the same stuff, and at least has the decency to make some bizarre (and very likely false) predictions outside of the early universe.
Theories of the very early universe that require new fields that there's a way to detect today are interesting. Certainly there are ideas to explain dark energy as an extension of inflation that fit that bill. But theories that propose a bunch of cool new physics that all conveniently vanished early on are a bit sketchy, at least until we can somehow make an equivalent of WMAP for the neutrino background radiation, and observe the very early universe directly. I hope I live to see that!
Socialism: a lie told by totalitarians and believed by fools.
In science, it's irrelevant if you admit it or not. Either your model works or not, and if it's not working somebody will come up with a better model and replace yours. People will use the better model because it works better. Or maybe I misunderstand you. Newton's laws of gravity works "almost right", Einstein's theory is better. But in cosmonautics and mechanics we use Newton's laws, because they are good enough.
http://www.mueller-public.de - My site http://www.anr-institute.com/ - Advanced Natural Research Institute
I was hoping that everyone was wrong and we get some new physics.
It's a Medium article. I think if you read it in detail you'll probably find they made up some new physics anyway.
Allowing AC posts like yours have ruined this site for years now. The owners and operators of Slashdot should have fixed this by now, severely restricting who has access to AC posting.
Maybe you haven't looked at many science stories on here, but there are numerous named accounts that will make wildly inaccurate and wrong on nearly every science story of various topics. They get modded up faster than coherent replies can be made pointing out how wrong they are, and often retain a net positive mod even after a dozen replies pointing out how wrong they are, letting them post the exact same mistakes again at a later time. And not just subtle mistakes, but stuff that directly contradicts the first sentence or two of a wikipedia lede.
The root of problems around here with science topics has very little to do with what name people post under.
Would you have made your original reply to my post if you had had to use your real account name?
Quite a few actual scientists post here and elsewhere anonymously as possible. It takes one whack job with too much free time getting upset over the stupidest things then using your easy to find department listing to spam or harass you. I've had it happen over stuff as benign as trying to explain intro level electrical circuits, while a colleague had it happen over what amounted to a west-vs-easy difference in name of an effect. Most researchers just end up stopping to answer questions online once their enthusiastic youth wears thin, while a smaller number just drops their name from things, and fewer bother to actually try weathering the storms.
And besides, I've found when you have a point to make, it makes no difference whether done here as an AC or with some pseudo-anonymous name. The only people who seem to care are those that have no actual counter point.
If you had bothered to read the first sentence of the quote -- and were able to comprehend it in context -- then you would not have posted this grammatically-challenged reply.
That is a rather crappy context, and you can far better understand it by reading some of Penrose's, among other's, actual papers. But it doesn't contradict that inflation can neatly package up a lot of things in a unified idea, usually something considered the opposite of a kludge in physics. It is not the only explanation with some traction these days and there is a lot to be said about criticism of inflation, but just ranting about what name a person posts under doesn't amount to anything in that regard. Maybe if you are going to complain about people using personal attacks in place of knowledge, you should lead by example.
I still choose to believe that the CMB cold spot is a parallel universe entangled with ours, and I want my belief treated with respect. #teachthecontroversy