No Shadow From the Big Bang? 178
ultracool writes "In a finding sure to cause controversy, scientists at The University of Alabama in Huntsville (UAH) found a lack of evidence of shadows from "nearby" clusters of galaxies using new, highly accurate measurements of the cosmic microwave background (WMAP). Other groups have previously reported seeing this type of shadows in the microwave background. Those studies, however, did not use data from WMAP, which was designed and built specifically to study the cosmic microwave background."
Re:Existensial? (Score:5, Informative)
Shadows require light, an object and an observer. The 'observer' is us here at the earth. The 'object' is this (from TFA):
Galaxy clusters are the largest organized structures in the universe.[snip] The gravity created at the center of some clusters traps gas that is hot enough to emit X-rays.
This gas is also hot enough to lose its electrons (or ionize), filling millions of cubic light years of space inside the galactic clusters with swarming clouds of free electrons. It is these free electrons which bump into and interact with individual photons of microwave radiation, deflecting them away from their original paths and creating the shadowing effect. This shadowing effect was first predicted in 1969 by the Russian scientists Rashid Sunyaev and Yakov Zel'dovich.
And the 'light' is the background microwave radiation, until now assumed to be from the edges of the universe, beyond these clusters.
Beneficial Mutations (Score:4, Informative)
Evolution of a new enzymatic function by recombination within a gene. Hall BG, Zuzel T, Proc Natl Acad Sci U S A 1980 Jun 77:6 3529-33
Abstract: "Mutations that alter the ebgA gene so that the evolved beta-galactosidase (ebg) enzyme of Escherichia coli can hydrolyze lactose fall into two classes: class I mutants use only lactose, whereas class II mutants use lactulose as well as lactose..." (Obviously, in a lactose-rich environment, this makes E. coli more fit.)
Now that I pointed you to the paper will you give up your unfounded belief?
I'd also suggest reading this [talkorigins.org] to start and maybe this [amazon.com] to learn a bit more about evolution.
Re:Shadows really expected? (Score:5, Informative)
The article is probably a bit misleading. The Sunyaev-Zel'dovich effect [uchicago.edu] seems to come from inelastic Compton scattering. This leads to a distortion of the original blackbody spectrum of the CMBR. The term "shadow" merely comes from the observation that at lower frequencies there are less photons being detected since they are shifted to higher frequencies.
Feeding a troll (Score:5, Informative)
* peppered moth: selection for wing coloring
* mutations in HIV after it jumped species to humans. Many other mutations are observed in bacteria and other pathogens that make them resistant to drugs. We are currently waiting in fear for the birdflue to undergo such a change.
* Invasive species: many mutations are observed in invasive species that make them more adapted to the environment.
* Recently, direct observation of the evolution of beak size in Darwin's finches was reported (Science 14 July 2006: Vol. 313. no. 5784, pp. 224 - 226)
* Evolution of RNA sequences: many experiments have evolved RNA sequences that perform various functions. One example among many is converting an RNA enzyme to a DNA enzyme (http://www.sciencedaily.com/releases/2006/03/060
* Artificial evolution: in many experiment run in computers, evolution is able to create new structures, from bridges to sorting algorithms
Finally, I think it is worthwhile to mention one important piece of evidence that has recently been completed. When Darwin suggested in the 19th century that humans and apes had a common ancestor, he was ridiculed. Till then humans were seen as different from all animals, having been created on a different day of creation. In that time, nothing was known of the DNA. Today, we managed to sequence the human and the chimp genome. We know that humans and chimpanzees differ in 1% of their DNA sequence. In fact, the DNA sequence of a human is closer to that of a chimp than the chimp is to an Orangutan, or than the chimp is to any other living species, with the exception of the bonobo. The human is the chimp and bonobo's closest relative.
I think that is quite an amazing prediction to make more than 100 years in advance. In fact, predictions like this are the strongest corroborations in science: making a prediction that is absolutely unthinkable based on the current belief.
Thank you (Score:2, Informative)
http://www.msnbc.msn.com/id/14681924/ [msn.com]
more info and a quick question (Score:3, Informative)
Linkys
A primer on the SZE [uchicago.edu]
[PDF WARNING]
Their paper on astro-ph [arxiv.org]
The WMAP 3 year results paper [nasa.gov]
[/PDF WARNING]
Re:Feeding a troll (Score:1, Informative)
That turns out not to be the case [talkorigins.org]. It's also fairly irrelevant as far as the evidence for evolution goes.
Showing how a species evolves into a wholly different species capable of breeding among themselves but being unable to breed with the former species would be a remarkable proof.
Reproductive isolation in the presence of mutation and recombination is more than sufficient. When two subpopulations do not interbreed, their genomes begin to diverge; eventually the populations are different enough that they cannot interbreed even if re-exposed to each other. Not only has speciation been directly observed [talkorigins.org] (also here [talkorigins.org]), the fact that all known species share common descent is proven beyond all reasonable doubt by the twin nested hierarchy of genetic and morphological evidence. Sadly, creationists require unreasonable doubt.
Re:Feeding a troll (Score:3, Informative)
An environment that undergoes a change will cause members of a species that are not capable of handling that change to die off. Those that are left behind will have traits that allowed them to survive. The result is a small variation of the species that makes them better able to handle their (new) environment.
We have directly observed this, in action, at small scales (where life spans are short, such as in bacteria or even fruit flies).
These new variants of the species have small changes in their DNA that separates them from their brothers and sisters. The new DNA can still intermingle with the old, and the traits can be passed around the population.
If two sets of organisms are kept in isolation, though, they will develop more and more mutations that set them apart from their cousins, since the traits cannot intermingle. Since sexual reproduction only works when both sets of DNA are reasonably compatible, you reach a point where these minor changes add up to make the two populations sexually incompatible and they fail to reliably reproduce. This is the point where most people draw the line between two different species. This border situation is staring you in the face in the form of mules. (The two sets of organisms do not actually have to be in physical isolation; cosmetic mutations have been observed to cause two populations in an otherwise single species to isolate themselves. They only want to mate with others that look like them.)
It should be readily apparent how many small adaptations (from natural selection), which we have observed, directly, will result in speciation. All of this is part of evolution.
So you're real? You're not a troll? (Score:5, Informative)
Lets jump over your yawns to darwin's finches. How many species of finches live on the galapagos islands? I think it is wrong to call them all "one species". What about the different species of giant tortoises, are they also all one species? How come we can not recreate the species from which we have a single male left over - (lonesome george)? Before Darwin, people had no problem with calling all the different finches on the Galapagos island different species. It is just that on the Galapagos island it is so obvious that they all had a common origin, that Darwin had to conclude that species can not be stationary, they must change. And, after "on the origin of species" was published, people had to change the concept of species in order to try to still hold the immutable species concept. The changes that are observed now in one species of finches on the galapagos are similar to the changes that lead to the evolution of the different species. Are they a new species? Not yet. Will the become a new species? Who knows, but our current observations and thought do not provide any barrier that would prevent them from doing so.
* In vitro evolution, or artificial evolution are models. Just as we compute the path of a spaceship or the planets, or an atomic bomb in a model, we do a model of evolution. Without models, science would not exist. A model turns theory into predictions. These models tell us that conceptually, Darwin's idea of natural selection works. This is not clear to begin with, and certainly not all types of natural selection work.
The in-vitro models of evolution allow us to understand how the process of evolution works. There actually is a branch of the philosophy of science that believes that one can not test theories using observations. That one always needs a controlled experiment, and that observations in nature can never be controlled enough. (But I don't buy into this)
One needs to distinguish between concepts.
* Common descent
* Natural selection
* Speciation
* Evolution
Common descent is what tells us that chimps and humans had a common ancestor. Do you have any other reason for explaining why the DNA of chimps and humans are so close?
Natural selection is what creates functions in organisms. As was stated above, this is observed often - though the timescale at which things happen is quite long.
Speciation is a complicated concept. It seems that there are different ways in which a new species can arise - it can first use a different niche, and then stop being able to mate, or fist stop being able to mate (maybe because of a mountain in the middle), and then diverge in function. We do observe all stages of speciation separately, but the concept of the species is not defined well enough to point at cases where we observed a new species arising (see HIV example above).
Evolution includes all the concepts above. You seem to want to talk about evolution as speciation - I have no problem with that. Let us talk about that for a second. However, I'll drop the species concept. I think the species concept is a historical artefact that we inherited from pre-darwinian biology. Instead I'd like to know which two organisms that we observe on earth, according to your opinion are so different that they do not share a common ancestor.
So, you do accept that HIV and SIV share a common ancestor, right? As do the finches with the shorter beaks and those with the longer beaks mentioned above?
What about the other finches on Galapagos island? Do they have a common ancestor? Which of them do?
What about the chimpanzees? Currently we have chimps living in Africa all the way from the Kongo to the western shores of Africa. It is debated
Big Bang observations (Score:3, Informative)
Point a microwave receiver at the sky, as Penzias and Wilson did in 1963, and you're directly observing something called the "surface of last scattering", only a few hundred thousand years removed from the Big Bang.
>the singularity. It's the elephant in the room.
It's funny how confident textbook authors can get when physics can't answer questions a child would ask. At the end of the 19th century stuffed shirts were saying that physics was over except for adding a few decimal places to known quantities, but couldn't answer "Daddy, why does the sun shine?". All we have is speculation for the most interesting question we can imagine, that of how the universe first came into being. We've got reasonably supported answers to "what happened" from about a nanosecond onward after the Event but are stuck on "How" and "Why".