Rare Earth element tellurium detected for the first time in ancient stars
February 17, 2012 by Jennifer Chu
An image of an ultra pure tellurium crystal.
Nearly 13.7 billion years ago, the universe was made of only hydrogen, helium and traces of lithium — byproducts of the Big Bang. Some 300 million years later, the very first stars emerged, creating additional chemical elements throughout the universe. Since then, giant stellar explosions, or supernovas, have given rise to carbon, oxygen, iron and the rest of the 94 naturally occurring elements of the periodic table.
Today, stars and planetary bodies bear traces of these elements, having formed from the gas enriched by these supernovas over time. For the past 50 years, scientists have been analyzing stars of various ages, looking to chart the evolution of chemical elements in the universe and to identify the astrophysical phenomena that created them.
Now a team of researchers from institutions including MIT has detected the element tellurium for the first time in three ancient stars. The researchers found traces of this brittle, semiconducting alloy — which is very rare on Earth — in stars that are nearly 12 billion years old. The finding supports the theory that tellurium, along with even heavier elements in the periodic table, likely originated from a very rare type of supernova during a rapid process of nuclear fusion. The researchers published their findings online inAstrophysical Journal Letters.
“We want to understand the evolution of tellurium — and by extension any other element — from the Big Bang to today,” says Anna Frebel, an assistant professor of astrophysics at MIT and a co-author on the paper. “Here on Earth, everything’s made from carbon and various other elements, and we want to understand how tellurium on Earth came about.”
‘In the halo of the Milky Way,’ a rare element found
The team analyzed the chemical composition of three bright stars located a few thousand light-years away, “in the halo of the Milky Way,” Frebel says. The researchers looked at data obtained from the Hubble Space Telescope’s spectrograph, an instrument that splits light from a star into a spectrum of wavelengths. If an element is present in a star, the atoms of that element absorb starlight at specific wavelengths; scientists can observe this absorption as dips in the spectrograph’s data.
Frebel and her colleagues detected dips in the ultraviolet region of the spectrum — at a wavelength that matched tellurium’s natural light absorption — providing evidence that the rare Earth element does indeed exist in space, and was likely created more than 12 billion years ago, at the time when all three stars formed.
The researchers also compared the abundance of tellurium to that of other heavy elements such as barium and strontium, finding that the ratio of elements was the same in all three stars. Frebel says the matching ratios support a theory of chemical-element synthesis: namely, that a rare type of supernova may have created the heavier elements in the bottom half of the periodic table, including tellurium.
No ordinary supernova
According to theoretical predictions, elements heavier than iron may have formed as part of the collapsing core of a supernova, when atomic nuclei collided with huge amounts of neutrons in a nuclear fusion process. For 50 years, astronomers and nuclear physicists have modeled this rapid process, named the r-process, in order to unravel the cosmic history of the elements.
Frebel’s team found that the ratios of heavy elements observed in the three stars matched the ratios predicted by these theoretical models. The findings, she says, confirm the theory that heavier elements likely formed from a rare, extremely rapid supernova.
“You can make iron and nickel in any ordinary supernova, anywhere in the universe,” Frebel says. “But these heavy elements seem to only be made in specialized supernovas. Adding more elements to the observed elemental patterns will help us understand the astrophysical and environmental conditions needed for this process to operate.”
Jennifer Johnson, an associate professor of astronomy at Ohio State University, says tellurium has been a “tough” element to detect, since it absorbs light in the ultraviolet spectrum, which is impossible for ground-based telescopes to spot. The team’s findings, she says, are a first step in identifying some of the most elusive elements in the universe.
“If you look at the periodic table, tellurium is right in the middle of these elements that are hard for us to measure,” Johnson says. “If we need to understand how [the r-process] works in the universe, we really have to measure this part of the periodic table. It’s really cool that they got this element in this sea of unknown-ness.”
Frebel is continuing the search for heavy elements in space. For example, selenium — which is similar to tellurium — has yet to be detected in the universe. Tin, Frebel says, is also a difficult element to spot, as are many elements along the same row as tellurium in the periodic table.
“There are still quite a few holes,” Frebel says. “Every now and then, we can add an element, and it adds another data point that makes our work easier.”
Journal reference:
Astrophysical Journal Letters
Provided by
Massachusetts Institute of Technology
This story is republished courtesy of MIT News (http://web.mit.edu/newsoffice/), a popular site that covers news about MIT research, innovation and teaching.
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Feb 17, 2012
Rank: 3.2 / 5 (13)
This is a science website, not a site for discussing delusional fantasies.
Feb 17, 2012
Rank: 3.9 / 5 (7)
Although I see your point, you got a better idea? Heck, does anyone?
Let's not forget we(past humans) believe that Earth was at the center of the universe and that the Sun(and everything else) revolved around us(also called geocentrism).This of course was later proved false. The point is without someone believing this, no one would have thought to disprove it.Although we don't know the Big Bang is fact, we have no better explanations, if you have one, please share. (Please don't bring G-d into this, he/she/it doesn't count) Also, the theory does follow from what we already do know about supernovae, it creates heavier elements then fission
Feb 17, 2012
Rank: 1.2 / 5 (10)
Since you admit the Big Bang is not fact, can you kindly quit forcing it down everyone's throat in school and university?
Cold fusion and particle collision experiments also create heavier elements, sometimes even stable isotopes.
Feb 17, 2012
Rank: 1 / 5 (2)
Honestly, I wouldn't mind if someone brought God (or Allah, Jehova, etc) up. I would ask those people to follow the scientific method though, which states (in a nutshell) that i) it has to be proven and ii) it should be reproducible by other people.
Feb 17, 2012
Rank: 2 / 5 (8)
In the most recent meeting of our astronomy club, we had similar discussions. In any search engine enter HUDF-JD2, a galaxy 5-8 times more massive than Milky Way & every bit as mature at 13 Gly ago, redshift @ z=6-7. If this galaxy is as mature as suggested, the universe must be more than 13.7 billion, a lot more, otherwise it would have had to form within 800 million years of the BB.
Universal galactic density & type seems to be about the same no matter where we look, therefore time of the BB may even be a trillion years ago because we observe no thinning of galactic density.
Feb 17, 2012
Rank: 1.8 / 5 (5)
Much of the data that is present SUPPORTS the big bang theory. Some data doesn't.
2 possibilities
1. The theory is not correct
2. The data is not correct.
Explanation 1: The theory might be off. Please challenge it, combined with data and maybe an alternative (or in which direction one is thinking perhaps).
Explanation 2: The measurements that are performed to challenge the big bang are often not reproducible or from suspicious sources.
Point is much people tend to hear something and go on yelling it without really having a clue.
Yup, could be. Although Cold Fusion is not yet invented or scaled up. You could really get rich by telling people how to...
Feb 17, 2012
Rank: 5 / 5 (5)
It's being taught as a THEORY (one of many) not as the truth, or fact.
What do you suggest? We tell people the world is flat? The center of the universe? Created 3.000 years ago? Creationalists still trolling around in the 21st century, spreading their nonsense like desease? Well, at least that's a proven fact.
Feb 17, 2012
Rank: 1 / 5 (9)
NASA has a LENR device patent. They just haven't figured out a way to make it practical yet.
the reason I made that comment with regards to this discussion is simply to point out the heavy elements have other known sources than just supernovas, and therefore the standard model explanation of where terrestrial planetary matter and other heavy elements comes from is already called into question.
If "heavy electrons" exist in a lab, maybe they exist in nature too.
If Rossi's device is real and works in a lab, maybe similar stuff happens in nature too.
Why is it that the planets and asteriods in the SS have tremendous amounts of iron and nickel, and other heavy metals, but the Sun has almost nothing. The Sun is much bigger in size and gravity than any proto- planet would have been, so it should have trapped the majority of material from alleged supernova.
Feb 17, 2012
Rank: 2.1 / 5 (14)
Fraid you're mistaken.
I had college professors go so far as to claim that the BB and Evolution should be considered "Laws" on par with gravity and conservation laws.
It is taught as a fact, and to the exclusion of all competing models or philosophies.
The forum mafia here is no different.
Suggest something is wrong with a model or theory, and they show up in pairs to denigrate you and call you psychotic, etc.
Feb 17, 2012
Rank: 3.5 / 5 (8)
This has been confirmed by so many observations, and has made so many accurate predictions that you would have to be delusional to deny it.
The power of a theory is in the predictions, and the Big Bang model succeeds in making accurate predictions about our universe.
Get over it nutjobs. Reality does not care about your opinion.
Feb 17, 2012
Rank: 3.6 / 5 (5)
This is a trivial question. The answer is in any first year astronomy book. I did plenty of trivial problems back in first year astronomy calculating the makeup of the solar system based on simple chemistry.
You're just uneducated.
Feb 17, 2012
Rank: 5 / 5 (4)
Feb 17, 2012
Rank: 1.3 / 5 (9)
Feb 17, 2012
Rank: 5 / 5 (6)
Feb 17, 2012
Rank: 1.4 / 5 (9)
Actually, that's not true at all.
It was cited above about Galaxies being given ages that are far too old for their alleged place in the universe to be consistent.
the Big Bang model does not make accurate predictions at all, and changes in the laws of physics were invoked to "patch" that, including Inflationary period in which matter moved faster than the speed of light, as well as DM and DE and more.
In essence, the observations REFUTE the BB model, and so they invoked changes in the laws of physics, as well as symetry breaking and other similar nonsense in a vain attempt to cover up this embarrassment.
dtyarbrough I correct, they've even changed the definition of the BB model significantly in the past several decades, yet NONE of them are actually supported by observation either.
Feb 17, 2012
Rank: 1.3 / 5 (10)
further, if the inflationary period actually happened, then dating the universe is impossible, since the vast majority of dating methods in cosmology are based on the limitations of the Speed of Light and the theory of relativity.
If the speed of light changed in the past, or if the laws of Relativity changed in the past during this alleged inflationary period, then you could no more prove whether that happened 10,000 years ago, or a billion years ago, or ten billion, or 50 trillion.
Just as an obvious example, Galaxies which are say, 7 billion LY distant from one another could not have moved that distance in 13 to 15 billion years anyway, because they are currently moving away at only half the speed of light, BUT according to Dark Energy model and the Hubble Constant, they would have been moving must slower in the past.
In fact, galaxies adjacent to one another barely move at all.
Feb 17, 2012
Rank: 1.4 / 5 (10)
After all, during the first many, many eons, it is only moving 72km/s/mparsec.
At that rate it would take the universe roughly 9 BILLION, with a B, years just to expand from 1mparsec radius to 2mparsec radius.
I've continually had to point out inconsistencies like this and how it proves that the observations simply do not support the theory at all.
One day, someone in the scientific community will develop the intellectual integrity to admit this.
Feb 17, 2012
Rank: 1 / 5 (10)
Which means it could never have formed by an explosion from an ultra-dense state in the first place.
Feb 17, 2012
Rank: 4.6 / 5 (9)
You have no idea what you're talking about. There is no problem with relative velocities greater than the speed of light due to expansion of space.
Special relativity is for Minkowski spacetime you n00b.
Learn2physics
I actually have a physics degree
Feb 17, 2012
Rank: 1.4 / 5 (7)
Not true.
It's all a matter of the distance to the "epi-center" of the explosion from where we are today. If we are a trillion light year's distance from the "epi-center, then HUDF-JD2 is almost within our galactic neighborhood by comparison & this would explain its' size & similarity to oue own galaxy.
How did we ever get the idea the Universe is only 14 billion years old? Because that's the distance a bunch of old telescopes could see in the 1930's ? If I went super-luminol right now & landed on a planet inside HUDF-JD2 & orbited a Spitzer telescope around it & viewed line of sight opposite the Milky Way, I have little doubt what I'd see, more of the same of what we see from the Milky Way as we look in the direction of HUDF-JD2, I judge that by the already known size of HUDF-JD2 & how similar it is to Andromeda. Galactic density does not thin between here & there.
Feb 17, 2012
Rank: 4 / 5 (1)
Actually, this is a really interesting idea (though not a new one - see Susskind and 't Hooft). I like to think that every black hole forms a new universe. I imagine the formation of a universe on the "other side" of the black hole would be something like the bounce-back effect that produces a supernova; just in terms of space-time rather than physical material. It would look just like what we call inflation.
Totally untestable speculation of course. A boy can dream.
Feb 17, 2012
Rank: 4.6 / 5 (10)
There is no "epi-center" of the explosion. That makes no sense at all.
The universe is isotropic and homogeneous. The big bang happened "everywhere" simultaneously.
There is no single "point" where the big bang occurred, and anyone who says such a thing has zero understanding of cosmology.
Feb 17, 2012
Rank: 1 / 5 (10)
Sorry pal, the textbooks, the encyclopedias, etc, all alleged the age of the universe is somewhere between 13 and 15 billion years old, although it's been bumped up a few hundred million years as slightly better telescopes increases the range from 13billion to about 13.7 to 13.9 billion LY.
Yet another "scientists" who doesn't even know what his own theory says.
en.wikipedia.org/wiki/Age_of_the_universe
No wonder I have so much trouble on this site.
The damn scientists an forum mafia don't even know what their own theory claims to say.
This is the standard model. Get over it.
It's clear that you do not agree with it either, you were simply to ignorant and misinformed to realize it.
The old text books and encyclopedias actually claimed there was exactly that.
The change in the description came a few decades ago.
Either way, it doesn't work anyway.
Feb 17, 2012
Rank: 5 / 5 (6)
Wait... do you think every commenter on this site is a scientist? You just keep fighting back the scientist hordes with your sword of truth there, Quixote.
Feb 17, 2012
Rank: 4 / 5 (8)
Feb 17, 2012
Rank: 5 / 5 (11)
Citation needed.
Prove to me that physicists ever actually thought the big bang was an explosion from a point.
The only time anyone ever says that the big bang started at a point is in popular science TV shows and books meant for the general public.
You are just a troll, and a terrible one at that. You have no understanding of the principles of general relativity or cosmology.
The things you are bringing up as "problems" with the BB model are trivial and stupid questions that you could easily find the answers to in a basic textbook.
Literally every single "problem" you have fabricated in this thread is trivial and irrelevant.
Feb 17, 2012
Rank: 5 / 5 (9)
For those who haven't taken astronomy courses, the answer is simple. By mass, 98% of the Sun is hydrogen and helium. Rocky bodies are too small to hold those. Much of the rest is other volatile elements, either gases or low-boiling point solids. Those would also be lost to small bodies close to a star. All that's left are the "refractory" materials, such as metals and silicates.
Feb 17, 2012
Rank: 5 / 5 (4)
Exactly right.
Feb 17, 2012
Rank: 4.3 / 5 (6)
Feb 17, 2012
Rank: 1 / 5 (8)
en.wikipedia.org/wiki/Georges_Lema%C3%AEtre
Specifically states that the universe exploded from a Singularity.
"There he proposed that the Universe expanded from an initial point, which he called the "Primeval Atom" and developed in a report published in Nature."
Ok, you guys lose again, proving you DON'T KNOW YOUR OWN THEORY.
Feb 17, 2012
Rank: 1 / 5 (3)
How do you know there is no single point? In your opinion there was no "explosion"? Everything we see out there today, just sort of showed up or what? You want to be the teacher here, and I'm willing to be a student.
Feb 17, 2012
Rank: 1 / 5 (7)
Now that I've given a citation, which anyone with any integrity could have found for themselves with a 30 seconds effort...
Ghost and the rest of the forum mafia sticks his head out again, and once again, I use the mainstream articles and encyclopedia to show that he is the one who actually doesn't know what he's talking about.
"There he proposed that the Universe expanded from an initial point, which he called the "Primeval Atom" and developed in a report published in Nature.[11] Lemaître himself also described his theory as "the Cosmic Egg exploding at the moment of the creation"; it became better known as the "Big Bang theory,"
There I re-quote the entire passage, in case any of you dishonest people want to try to twist this any more.
Feb 17, 2012
Rank: 5 / 5 (9)
The big bang started of an expansion - not an explosion. Two entirely different concepts. Even George Lemaitre (the one you cited) got that right:
Explosion: Stuff moves away from one another in a a static space.
Expansion: Stuff moves away from one another due to the expansion of space it is in.
Feb 17, 2012
Rank: 5 / 5 (1)
Additionally - the sun being a ball of gas for all intents and purposes - heavy stuff tends to sink to the center. We only get to see (measure) what's on the outside (and make some very rough inferrences via seismic measurements of what's on the inside)
Feb 17, 2012
Rank: 1 / 5 (4)
So why suddenly so much concern about a standard model for age? The distance 1930's, 40's, 50's, 60's, 70's, & 80's, telescopes could view the Universe is supposed to be the "standard model"?
You bet, "Get over it", we're almost beyond the age of even the Hubble telescope, we've got Spitzer out there with some astronomers claiming they'll be able to use it beyond z=10, and so far they're not exactly finding things they expected to see. Mark my words, ten years from now we'll all be reading about a finite 100 billion year old Universe.
Feb 17, 2012
Rank: 1 / 5 (3)
Expansion: Stuff moves away from one another due to the expansion of space it is in.
OK, I'll give you that. So at what point in distance do we expect to see "thinning" and reduced "galaxy density"? So far It's all pretty much the same in any direction we point Palomar, Griffith, Hubble or Spitzer telescopes, and we're still no closer to finding an "edge of the universe".
An "explosive epi-center" is a sacred cow. Count for me the cosmologists who want to do away with that, they're all standing in front of the Griffith Observatory with many implying all galaxies were created at a single moment in time, then "inflation" set in. So, how long has inflation been going on? I'm the student here.........
Feb 17, 2012
Rank: 1 / 5 (4)
I don't doubt the universe itself is finite, certainly from some "reference point".
A_P:
Re-read the quote. Lemaitre used both the terms "expand" and "explode".
I mean, regarding the "single point" argument, this is even directly form the article on the Big Bang:
"Extrapolation of the expansion of the Universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past".
youtube.com/watch?v=uabNtlLfYyU&feature=related
Yet another video explaining the BB as claiming the universe started as an infinitesmal point in space.
Why no outrage from the mainstream theorists at this, if it was never what the BB claims?
Once again, my post is supported by the facts and links I've provided.
Hilariously, the narrator says the solution to the universe needs no cause, undermining the "where did God come from" argument...
Feb 17, 2012
Rank: 5 / 5 (8)
We'd only see thinning if it were an explosion not an expansion.
An expansion means that basically EVERY point in the universe is the point where the big bang was - so naturally we should not see a thinning in any direction (this is also the reason why the cosmic microwave background looks pretty much the same in every direction - every direction 'points' to the big bang ).
We should, however, see only younger stars the further we look (since the light has travelled accross space and we are therefore looking at stars as they were in the past)
There is no edge in such an expansion (only in an explosion would there be an edge). We do not have a cartesian space.
Feb 17, 2012
Rank: 5 / 5 (5)
The age of the universe was determined by the receding velocity of distant galaxies. following it backwards, 13.7 billion years ago, all of them should be at the same place. That determines the age of the universe. Not how many billion lightyears away we can see objects. And that answers your previous question: every point is the center piont.
By around 2025 there will be four telescopes operational that will be able to see the light from population III stars. I can't wait.
Feb 17, 2012
Rank: 1 / 5 (7)
Wouldn't be able to tell the difference, since the standard practice is to automatically date distant galaxies as proportional to their distance.
therefore, the cosmologist will simply assign an "age" to the star corresponding to the theoretical age of the galaxy, contaminating any comparison that could be made.
Feb 17, 2012
Rank: 4.5 / 5 (8)
We can also date by hydrogen content. Early stars should have a higher hydrogen content and less heavy metals (which are products of the late stages of stars). Very early stars should be almost all hydrogen, helium and a bit lithium (also they should be fairly big and therefore short lived), but we have no telescopes that can look back that far yet
It is also possible that when they formed (since the universe was a lot smaller back then) they were obscured by the much denser surrounding nebulae of hydrogen. Which would make them doubly hard to observe today.
another way to date is by standard candles of which there are a few
http://universe-r...m#type1a
Redshift isn't the only way. The different methods complement each other. Age isn't simply 'assigned'.
Feb 17, 2012
Rank: 3.4 / 5 (5)
"a spatial point is a primitive notion upon which other concepts may be defined. In geometry, points are zero-dimensional; i.e., they do not have volume, area, length, or any other higher-dimensional analogue."
-In other words a point needs dimensional space in order to define it as such. The singularity which presaged the big bang did not exist in dimensional space; ergo it was not a 'point'. Isnt this correct AA?
Feb 17, 2012
Rank: 5 / 5 (5)
Oh THAT is what you think it proves?
Erm. I'm sorry to burst your bubble: but all your 'observations' ever do is how little you understand of the subjects at hand (and how little reading/research/double-checking you did do before posting...My guess would be: None at all?)
One day someone in the teaching community will lead you close to a textbook. Maybe after learning (and more importantly: understanding) a bit will you admit that you just have (by then: had) no clue whatsoever about pretty much anything - not even the bible.
Feb 17, 2012
Rank: 1 / 5 (5)
Sure, but that was as far as we could see at the time. The CMBR only measures in radio waves about what we see optically, and it measures a consistent density of galaxies right up to that limit, there is no thinning.
The big problem is that there is HUDF-JD2 right at the cusp of that 13.7 billion lightyear limit, and you are implying there can be no more universe much beyond that point just because current electronic radio receivers aren't sensitive enough to pick up weaker signals beyond that distance? Same for optics. I wonder what Galileo was thinking about a few days, or weeks, after he first saw the four moons of Jupiter, probably something along the line of: "If I build a bigger telescope, I'll betcha I get even more surprises".
Yep, build better radar, better optics, and let's continue to be surprised like when we found HUDF-JD2.
Feb 17, 2012
Rank: 5 / 5 (10)
*Sigh* Expansion. Remember? You really need to let go of the 'explosion' idea. It's as wrong as wrong can be.
Hubble Deep Field shows us objects up to 42 billion light years away (like HUDF-JD2). Yet the picture we see is from it as it was 13.7 billion years ago.
Space expands (and keeps doing so) - even WHILE the light travels. That's where the redshift is coming from in the first place. The redshift does not happen because we have different motion vectors but because the space in between expands (like dots on an inflated balloon. They don't move by themselves but still get farther away from each other because the medium expands)
Feb 17, 2012
Rank: 5 / 5 (1)
Hmm, I maybe should have quoted the lot. Thanks otto, nicely said.
Feb 17, 2012
Rank: 5 / 5 (7)
That's when the ionized stuff got cold enough to form atoms. Before that we had just ionized stuff flying around and light couldn't get very far due to Compton scattering - so we don't see anything from before that time.
Actually we don't see much extra after that for a while because it takes some time for large enough stuff to form so that we can see it at this distance...150-800 million years.
That's why stuff like UDFy-38135539 is so exciting because it falls in that era (about 480 mio years after BB).
Feb 17, 2012
Rank: 5 / 5 (2)
Time is proportional to space. You can't make that go away just by wishing it. Or do you think the Doppler effect isn't a reliable yardstick?
According to your ideas, the age of the universe should be its size multiplied by the speed of light. But this can't be true, otherwise the CMBR would not exist (or at least we couldn't observe it).
Therefore the universe's expansion rate is not limited by C.
This is intuitive in set theory (consider C, M, E and the rest are set members in the universe). May I recommend wiki -> point-set topology, Moore Space etc.?
I am not a physicist though, happy for the more rational posters to correct me.
Feb 17, 2012
Rank: 1 / 5 (5)
Feb 17, 2012
Rank: 5 / 5 (4)
Proof by verbosity (argumentum verbosium, proof by intimidation) submission of others to an argument too complex and verbose to reasonably deal with in all its intimate details.
Cherry picking (suppressed evidence, incomplete evidence) act of pointing at individual cases or data that seem to confirm a particular position, while ignoring a significant portion of related cases or data that may contradict that position.
Fallacy of composition assuming that something true of part of a whole must also be true of the whole.
Begging the question (petitio principii) where the conclusion of an argument is implicitly or explicitly assumed in one of the premises
Straw man an argument based on misrepresentation of an opponent's position
Fallacy of division assuming that something true of a thing must also be true of all or some of its parts
Kettle logic using multiple inconsistent arguments to defend a position.
Feb 17, 2012
Rank: 5 / 5 (4)
Abusive fallacy a subtype of "ad hominem" when it turns into name-calling rather than arguing about the originally proposed argument.
Wishful thinking a specific type of appeal to emotion where a decision is made according to what might be pleasing to imagine, rather than according to evidence or reason.
And of course, my favorite. (but i cant take credit, I learned about this one when someone else was arguing with an idiot on this site):
The DunningKruger effect is a cognitive bias in which the unskilled suffer from illusory superiority, mistakenly rating their ability much higher than average. This bias is attributed to a metacognitive inability of the unskilled to recognize their mistakes.[1]
Actual competence may weaken self-confidence, as competent individuals may falsely assume that others have an equivalent understanding.
Feb 17, 2012
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I'm not sure 'presage' makes any sense here. One dimensional objects have (by definition) no time vector. Then again: dimensions are a model of reality - not necessarily reality (map does not equal territory). It's really iffy when you take models to their extremes (like singularities and such) - they usually turn out to be nonsensical at these border condition cases (with infinities, missing time, .... ).
One PhD after my name is enough (got it 1.5 years ago), thanks. Not in astrophysics. But that has been my hobby since I was six.
Feb 18, 2012
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There are stars beyond everything we can see. MOST of the material from the big bang is now disconnected from our observable universe. The real location of CMBR is like a rainbow in that it moves back as you get closer to it.
I have always had trouble accepting it is a mere coincidence the calculated age of the universe is the same within the margins of error as the equilibrium light distance of the measured expansion rate of space. As we get better numbers it better start drifting.
Feb 18, 2012
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You can't see stars older than - lets say - 13.699 billion years. The stars were at such an early stage of their development, that they existed as a cloud of plasma, just in the process of cooling down enough to form atomic hydrogen. Before hydrogen, there were no stars.
Feb 18, 2012
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Feb 18, 2012
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Feb 18, 2012
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Feb 18, 2012
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Not quite. You can have finite, but unbounded space.
The standard picture for this (as for the big bang) is an expanding sphere (like a balloon). Space is the surface of the sphere (in our model the space only has 2 dimensions, but it's hard to conceptualize a 3D space expanding on a 4D volume)
This space is finite. The surface of the sphere has a finite 'volume' (in 2D the 'volume' would be the surface area). But it is unbounded because you can travel in any direction without encountering a boundary, ever.
If our universe is such a 3D space on a 4D hypersphere (analogous to the 2D space on a 3D balloon) then we could, theoretically, head off in one direction and would eventually come back to where we started from.
Problem is: Speed in this universe is limited to c and expansion along that route is faster than you could travel.
Feb 18, 2012
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Feb 18, 2012
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What is that?
Since these seem to be some of the oldest stars (i.e. first generation or early second generation) - probably not a whole lot. Some early giant stars. Primordial black holes. That sort of thing. But given the energy density of the early universe it certainly will be interesting stuff*
*Well, everything in the universe classifies as 'interesting stuff'
Feb 18, 2012
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Feb 18, 2012
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Kevin had the first 2 post on this article. They were remove even though he never mentioned anything about religion. He did bring up some good points that the believers in BB religion did not want to deal with. I suppose that is why his posts were deleted.
That is not very science like.
Feb 18, 2012
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Amount of space required to make c equal to total instantaneous measured rate of metric expansion across that space.
Feb 18, 2012
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Because we are. Expansion means that EVERY part of the universe was once where the BB happened. In a very real sense every part of the universe is the center.
So you can see why we see the background radiation the way we do. That radiation started off at the center (i.e. everywhere) 13.some billion years ago (or 15 billion depending on the exact specifics of the model)
So any of that radiation that has, due to the intermittent expansion, just no reached us is what we see as the CMB.
As someone else said:
This means that as long as expansion continues there will always be places that just now are so far away that the light from them (as center of the BB) will reach us at any one time. It will just be ever more red shifted.
Feb 18, 2012
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And this is? Specifically what is an "instantaneous measured rate"?
I ried googling it but there seems to be nothing of that sort in literature. So either my translation skills aren't up to the task or this is some gobbledygook that you came up with.
And if you simply mean the rate of expansion we measure then that is not on the order of c (except for a very specific distance).
The current value is somewhere arount 70 km/sec per Mparsec
Feb 18, 2012
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Feb 18, 2012
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Feb 18, 2012
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Feb 18, 2012
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You clearly don't have the foggiest idea of how cosmology works. The Friedmann equations describe a homogeneous and isotropic universe. Any n00b who knows something about ordinary differential equations can solve it and calculate the age of the universe.
Man, there's so many idiots in this thread making ridiculously stupid statements.
Feb 18, 2012
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Lets say expansion rate is 72km/s per mega parsec.
Lets say c is 299792km/s
The distance needed for the expansion rate to equal c is 4164 mega parsecs.
Converted to light years it is 13.6bn within margins of error this is also the calculated age of the universe.
If this holds as the error bars shrink with better data it will end up being one heck of a coincidence.
Feb 18, 2012
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Feb 18, 2012
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so? All this means is that we have looked as far as we can look (i.e that the stars in the night sky are those we CAN see). Anything beyond that will be over the visibility horizon.
What's so miraculous about that? It's a tautology.
Because EVERYWHERE you look you're effectively looking towards the center. So naturally it will look more homogeneous the further you look (i.e. the more you look into the past)
You're still thinking 'explosion' and 'movement away from each other via speed differences'. But we're dealing with an expansion.
Feb 18, 2012
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Feb 18, 2012
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You're still thinking 'explosion' and 'movement away from each other via speed differences'. But we're dealing with an expansion."
I find this a little baffling, a few post back you stated everywhere is the center, so how can you look back into your own postion or past or whatever? I mean is anything real?
Is there really much difference between and expansion that started from point or an explosion that started from the same point? I see little difference other than when the inflationary period had to be added to explain the apparent flatness of the universe. All that does is turn the expansion (explosion) into a supernatural happening.
Feb 18, 2012
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Question: in 13bn years from now what will be the expected output of this same formula? Will it still be 13.6 or something else?
If you answered the same you now see my point as to why it is interesting. Note I claim nothing with regards to what it means just that it is an interesting coincidence. One that gets increasingly interesting as we get better data.
If you say something else then either c (not likely) or the hubble constant is variable.
Feb 18, 2012
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http://www.amazon...p;sr=1-9
All you need to know is basic calculus and ordinary differential equations to understand it. You don't even need differential geometry or topology.
Feb 18, 2012
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Actually, if you understand this logics, you'll need not to solve these equations for being able to deduce the qualitative conclusion from this model, simply because the qualitative outcome of logical model cannot contradict its formal representation.
Feb 18, 2012
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This post provides valuable insight into why Rawalippo considers crackpot pseudoscience to be equal to, if not greater than, actual science. He is disconnected from understanding on a deep, conceptual level. He sees science as "random equations" and cuckoo science as being above "mere math". Little wonder, then, that rational arguments consistently fail to move him. You might as well place a call to a disconnected telephone.
Feb 18, 2012
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An example is what A&P stated: "We are looking back to the center in every direction we look."
It would appear in the BB theory this would be true but observations make that highly unlikely. Here is why, at every billion lightyears we look into the past we see more galaxies, we see more at 2 billion than at 1 billion lightyears distance and more 7 billion than 2 billion etc.. How can this be looking into an expansion when there is fewer galaxies observed with each passing billion years? It is true we are looking into the past but how can this be looking into the past of an expanding universe when every billion years we look into the past we see more not less galaxies?
Feb 18, 2012
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What the hell are you rambling about? When did I ever suggest physics is "a random pile of equations and substitutions"?
I think you need to get your head checked.
Feb 18, 2012
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Max Tegmark, a MIT teacher: The Mathematical Universe and Alan P. Lightman, a MIT teacher: We are living in a universe uncalculable by science
Feb 18, 2012
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Feb 18, 2012
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From purely technical perspective, the strictly deterministic approach is always less dimensional, than the holistic intuitive "crackpot", so that the intuitive thinking really has its last word in acceptation of most general models of reality. I do believe, we are living in random universe instead of deterministic one, because the former assumption is less demanding in accordance to Occam's razor principle. So that the intuitive approach to problem usually wins.
Feb 18, 2012
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As I demonstrated many times, the usage of mutually inconsistent postulates is the only way, how to derive at least something (if these postulates would be fully consistent, we could substitute them mutually) - but on the other hand such an approach always introduces a bias into result. This bias is the larger, the more you're depending on this strictly deterministic approach, because the reality is inherently fuzzy and deterministic logics is not complete enough for its description.
Feb 18, 2012
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Feb 18, 2012
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I'm sorry I don't understand. I think I've made it clear I'm not asserting or proving anything. Just pointing out what I think is an interesting coincidence. One I make no attempt to interpret.
My last message was in response to antialias who I believe didn't understand what I was trying to say. The question I posed was only a tool to help explain it.
Feb 18, 2012
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Feb 18, 2012
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Feb 18, 2012
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It's situation analogous to observation at the water surface, when the deterministic description of background independent surface ripples appears efficient up to certain distance. But after reaching of certain distance the dispersion of waves into dimensions of underwater cannot be neglected and the low-dimensional approach isn't useful anymore. The formally thinking people just hit the barrier of their own approach by now.
Feb 18, 2012
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Feb 18, 2012
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Feb 18, 2012
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Feb 18, 2012
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Feb 19, 2012
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Feb 19, 2012
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You're a crackpot
Feb 19, 2012
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I appreciate the fact that you are just bring up what you consider an interesting coincidence. I do not find it unusual, when you create a formula it usually is created to fit either an observation or a preconceived idea. The age of the universe formula is the latter.
The age of the BB universe does not fit the observed facts, that is why the idea of an "accelerating expansion" was added. The brightness of distant supernova did not square with the distance in the BB theory. They were dimmer than they should have been. The answer is simple add another major patch, along with inflation, an accelerating expansion!
Feb 19, 2012
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This is not a circular reasoning in its crystalline pure state?
Feb 19, 2012
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We can now ask as well: "How the universe would appear if it had looked like being eternal and infinite and the red shift would be a consequence of the dispersion of light at vacuum fluctuations"?
Apparently, many people today aren't willing to even think about it at all, thus effectively behaving like the opponents of Galileo in his era. The contemporary belief in Big Bang and the formation of Universe from "nothing" is the similar naive belief, like the belief in creation and another stuffs.
Feb 19, 2012
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......and he still won't tell us if he's ever had a course in Thermodynamics. A couple weeks back I asked him if he had, and instead of responding with a simple "yes", he danced around all around giving a direct response. I remember I had to have two semesters of calc as pre-reqs before before taking the 1st semester of Thermo. I think Cal/Rawa got wiped out in Trig long before he got to first semester Calc. If you notice, all his posts are devoid of mathematical concepts, and mostly just "touchy feel goodisms" that you can get on Sunday morning television.
Feb 19, 2012
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How is it possible after then, most of macroscopic effects in the observable Universe are actually driven with gravity, which has EXACTLY THE OPPOSITE effect and it tends to collapse and condense massive bodies into more dense objects spontaneously. Is this entropic effect too? If yes, how is it possible, the same macroscopic expansion is sometimes considered as an entropic effect, sometimes not?
If you can explain it in relevant way, then you're allowed to ask freely for my formal education in thermodynamics. But not before.
Feb 19, 2012
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This was answered to you !3 times! in other threads, please get lost.
Feb 19, 2012
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He's like a child that's proud in showing off his poop. He's not interested in learning how not to soil his pants.
Feb 19, 2012
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So once again: if gravity is entropic force, how is it possible, it leads into condensation and contraction - whereas the entropic processes (including the inflation of Universe) are connected with expansion?
Feb 19, 2012
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Feb 19, 2012
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Feb 20, 2012
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But we ned at least two dimensions to get anything going - and at least three to get anything non-linear going (which, I suspect, is a prerequisite for life).
Feb 22, 2012
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I just do not bother to look it up with the bad sitesearch,
but beacause its you i typed gravity entropy an thermodynamics into google and voila -> http://math.ucr.e...opy.html
Maybe you understand at least the first part and accept it, but i doubt that, so please get lost. ah! and: ololol
Feb 25, 2012
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The logic is indeed trivial, tired light would not produce the stretching of supernova curves which match the redshift exactly. It is in conflict with basic conservation laws for collisions and if you try to avoid the big bang model by suggesting a distributed source for the CMBR, tired light predicts a (nearly) flat spectrum instead of the black body curve we observe. It is a hypothesis which was worth a try when first proposed in the late 1920's but was refuted decades ago and fails grossly when compared to modern measurements.
Feb 25, 2012
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The logic is indeed trivial, tired light would not produce the stretching of supernova curves which match the redshift exactly. It is in conflict with basic conservation laws for collisions and if you try to avoid the big bang model by suggesting a distributed source for the CMBR, tired light predicts a (nearly) flat spectrum instead of the black body curve we observe. It is a hypothesis which was worth a try when first proposed in the late 1920's but was refuted decades ago and fails grossly when compared to modern measurements.
Feb 25, 2012
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Feb 25, 2012
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The wavelength of those ripples does not change with increasing radius so I don't know what you are trying to illustrate. Tired light was a suggestion that photons lost energy en route resulting in a gradually increasing wavelength but that would mean that supernova light curves would keep the same width with distance and they don't, the width matches the redshiftruling out tired light.
Yes it does - for a distributed source as I said but you edited out.
The image you cite is from here
http://www.astro....dlit.htm
That is for a thin shell source and still fails.
Feb 25, 2012
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Feb 26, 2012
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Part 1:
This is where handwaving and not looking at the maths gives you errors. Pulses are composed of a mix of different frequencies as you see if you take the Fourier Transform. In optical fibres, different frequencies travel with different speeds so a pulse gets broadened. Modern fibre systems use a comb of frequencies from a laser and modulate each frequency with a separate channel to engineer around that effect. The same phenomenon is used by astronomers to measure the electron density in space between us and a pulsar:
Feb 26, 2012
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Part 2:
The frequency dependence of refractive index is a fundamental property of all materials but in both the optical fibre and pulsar dispersion, each component frequency reaches the receiver at the same frequency as it was transmitted.
However, that is very different from cosmological redshift where we see spectral lines shifted in frequency by an ratio that is independent of frequency. In 1985, Wolfe et al studied light from quasar PKS0458-02. The quasar itself is at z=2.29 but the light from it passes through a gas cloud at z=2.039. The Lyman alpha line and the 21cm line have the same redshift to within 0.03% even though the frequencies differ by a factor of over 172,000.
Feb 26, 2012
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The depth of the water changes in that picture so the waves slow. The frequency remains the same (no "redshift") so the wavelength alters.
Yes. See parts 1 & 2 for details (though the links are missing)
Feb 26, 2012
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What we see is very precisely a black body, in fact it is so accurately a black body that it is a problem even for the big bang model. Assuming a perfect black body radiator with negligible optical depth is a ludicrous model but it is the most generous possibility for a steady state model but still fails. the reality is that steady state model had no explanation whatsoever for the existence of the CMBR.
Feb 26, 2012
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http://books.goog...wolfe%22 redshift frequency hydrogen&source=bl&ots=ozZTnf9p6d&sig=b0BR0xhbvfXW6yC3SffSWE1ciXY&hl=en&sa=X&ei=vzJKT_LEOIiu8gPWuMXSBg&sqi=2&ved=0CDEQ6AEwAg#v=onepage&q=%22wolfe%22%20redshift%20frequency%20hydrogen&f=false
Feb 26, 2012
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http://astronomy....p/Pulsar Dispersion Measure
Sorry for the messy posts, this site seems to have serious problems.
Feb 26, 2012
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