Ok, thanks for the link. I'll have to still dig up the original article, but it's a lot clearer.
In recent studies of deuterium in the galaxy, they're finding less than 1/25th of what they're expecting
According to the article, it's as much as 15% less than they were expecting. Not sure where 1/25 came from.
and almost entirely in the wrong places.
I don't know what you mean by "wrong", but if it's wrong for some isotopes to be trapped in grains, then a lot of them are in the "wrong" places. This has been supposed before, but I don't think anyone has detected it before now.
They therefore conclude that there must be MORE than what they expect, but in a place/form that is invisible.
You misread the article. This additional deuterium in the grains *gives* us more than we expected. Perhaps the nuclear reactions in some stars, or the rate of dredge-up before they eject their material, is somewhat different than we currently believe. Also, it is well-known that primordial material falls in on the disk of our spiral galaxy, so perhaps the rate of this infall is different (greater) from what used to be supposed.
Of course, we're all still probably idiots, so feel free to correct us after you're sufficiently amused by our floundering efforts.
By "not seen", we just mean that it doesn't *glow* like stars, not that it can't be detected at all. In fact, we detect it by the gravitational influence it has on neighboring luminous matter as well as lensing the light of background objects. We can study its large-scale nature and distribution fairly well, just not the composition or small-scale structure yet.
IAAAstrophysicist, so perhaps a good chunk of my brain has been consumed already, but are you certain you mean *deuterium*? Is there a cite for this? I worked on galactic chemical evolution, and I'm a little out of touch with recent developments in the field, but this is news to me. Or maybe we're all really as dumb as you think we are.
There are 4 inner planets, with similar properties and formation histories. There are 4 outer planets with similar properties and formation histories. Pluto belongs with neither, but has the most in common with what are now known as Kuiper belt objects. More and more of these are being found, some with supposed sizes greater than Pluto. One suggestion that, in my opinion, is the most reasonable is to recognize the 4 inner planets, 4 outer planets, and recategorize Pluto into the Kuiper Belt clan. Over and over in science, our first shot at categorizing things turn out to be unoptimal until we learn more about them. Recategorizing happens all the time as we learn more than merely superficial details about objects.
What is potentially troubling with this, and why I am skeptical of the implications for the Hubble constant, is that the age of the Universe had been narrowed down with a decimal point to 13.7 billion years, which means that the uncertainty in that number is +-100 million years or so. This is completely outside of the error bars. And the previous number had been honed in upon by not just the WMAP microwave background probe, but by many independent observations of Type Ia supernovae. It seems more likely to me that there is a systematic effect affecting the brightness of this binary star system observed in another galaxy than a confounding problem with WMAP or Type Ia. Also, it's a little odd to me to make Hubble constant inferences from a galaxy in our Local Group --- a galaxy that, together with Andromeda, is gravitationally bound to us (moving towards us) and doesn't obey the Hubble flow.
Wow that's a load of b**ls**t! I skimmed the article but now I know why I didn't read it:-)
So what's wrong with the original statement? Seems all right to me. Events that happened when the universe was 1 million years old are indeed at (about) a redshift of 1000, and the redshift is just telling us the expansion of the scale factor (size) of the universe, so any distance back then has expanded by the same factor of 1000.
Now, at 40, I think I'd rather be captured by terrorists and have my head sawed off rather than go back to school.
That imagery, since it has recently happened to actual people, is a little too disquieting to be tossed off as an innocent hyperbole.
But anyway, speaking downwind from a physics Ph.D., I have to say that I recall my grad school days as the best of my life. I'm a professor now, but if there was any way to actually raise a family and live on grad school fellowship/TA pay, I'd do it in a heartbeat. I got to hang around really interesting and smart people, think all day about fundamental physics and astronomy, conduct research and collaborate with the foremost experts in the world, be immersed in a collegiate atmosphere --- sports games, theater, international lecturers, beautiful campus. It's hard to imagine a more fufilling life from day-to-day.
I think the real litmus test is, "do you love your field?"
How do we figure out how far away they are? By measuring the redshift in the frequencies of their spectra. What do we use for that? The relativistic Doppler formula.
Only at pretty low redshift, though. At any redshift appreciably close to or greater than 1, there really isn't much meaning to "distance" --- would you interpret that distance to be at the time of emission, the time of detection, or somewhere in between? We basically just use the cosmological redshift, which says that the redshift z represents how much the universe has expanded since the radiation was emitted. That's it. Any "distance" or lookback time is model-dependent. Instead of measuring slight deviations in universal constants, they are perhaps measuring perturbations in a particular cosmological model.
In other words, the distance of the quasars -- and the frequency their light "should" be -- are highly model-dependent.
Right --- I'm just picking nits, since I've seen lots of confusion by others in similar reports.
Er, to get this AJAX app working properly you would need high-speed broadband and a pretty fast computer. Wouldnt it be easier just to install an easy, free spreadsheet app locally on the machine?
Maybe --- I'm not sure of the requirements. But I'd think that even the $100 laptop has a fast enough processor to do web requests. And as for easier, it's not clear, since one advantage of Google's system is the portability of one's data across a number of machines that may be community-owned. I'm even thinking in education, it's easier to post a spreadsheet for students to enter answers or data than manage lots of independently-made spreadsheets, and that data is immediately amenable to statistical analysis.
Yep, I think there's more to this than the myopic view of the American market. As a greater share of the world comes online, this will basically commoditize MicroSoft's software and shove it into a niche market. A very large percentage of average users would appreciate an easy, free spreadsheet they can access from anywhere and share with anyone else, including schools and nascent community internet centers in developing parts of the world. Maybe Google is really thinking globally and long-term. In 5 years it really could be the dominant method of casual information exchange.
You also might want to consider doing 2D animation with a 3D package.
I'll put in a plug for Animation Master. I use it for 3D animation, but I've seen some good examples of 2D animation and "cut out" paper-doll type stuff done with it, too. It's a really good package for $299 ($199 educational).
have no intentions of ever trying to teach in America after I had a friend fired in New York for mentioning the existence of evolution in a class.
Assuming the above is accurate and not hyperbole, it sounds like a slam-dunk case of wrongful termination, even if he had a *bad* lawyer, and your friend might even come through with quite a bit of cash. It's too bad you're accommodating those who would cheapen scientific education here in the US by not fighting their culture of fear.
..."any rebroadcast or retransmission of this program, without the expressed written consent of Major League Baseball, is strictly prohibited." And it's not limited, of course, to MLB.
Yep. For example, my students in physics and engineering will occasionally use Excel for fairly simple numeric computations --- figuring out dynamics from equations of motion, and so on. It's perfectly ligitimate to have 100,000 - 500,000 time steps for accuracy.
Right now, astronomers have some serious blinders on literally and figuratively. There are very few places in the sky where we can actually see objects that are far enough away to have cosmological significance. Even then, we can only see that far and not further. Modern cosmology is based on a limited view of the universe.
Very few places? We can see SN and blue compact galaxies down to redshifts of around 10, and can clearly see the CMB at a redshift of about 1100. Those are certainly cosmologically significant. What objects would you *like* to see?
Now we are finding some crazy shit. Stuff doesn't move the way it is supposed to. The crazy double super secret invisible "cosmological constant" and "dark matter" sound more to me like modern day epicycles than actual scientific theory. The scientific community does not like people who rock the boat, because they like to be right. Competing theories are pushed to the wayside, and something as innocent as sugesting that this universe or a universe existed before us and may have caused what we see today is contriversial.
Now that's just crazy. It's clear you're not a scientist. I remember when Perlmutter gave his initial SN indications of an accelerating expansion, he was met with wild derision at the conference I was attending. Astronomers (and physicists) *love* to prove each other wrong. New and bizzarre theories are rightly derided until they can stand up to the same level of rigor and evidence as the rest of the body of knowledge. It's clear now, after many more candidates have been observed, that Perlmutter was right.
could be wrong about things like the cosmoligical constant and dark matter or any other crazy theory I have in my head. My problem is that there are very few healthy debates on any of these untouchable theories. What debates that do occur can jeopardize dissenters' positions and funding. Now is not a good time for science in my view.
I strenuously disagree. All these cosmological mysteries make this a real Golden Age of astronomy. There are *many* healthy debates in the community and at the meetings, and most clearly and obviously in the current literature. Saying that dissent can jeopardize funding is absolute hogwash.
Since stars are basically point-like sources, they are prone to diffraction spikes caused by the telescope hardware itself. It's especially apparent when they are overexposed to enhance background objects. Typically the spikes are diffracted images of the supports for the secondary mirror of the scope.
It's not that the statement isn't literally accurate, but that, reading in context, his father was using the word "theory" in a diminutive sense and not as scientists use it.
Just catching up --- I think this is wrong. Life expectancies are a measure of how long, on the average, one expects babies born in a certain year to live. Extrapolating backwards is a wrong thing to do, because life expectancy generally goes up the longer one lives, since the mitigating statistics of childhood death have passed. Whereas one may be born with an expectancy of 70 years, after one successfully reaches 10 the average expectancy *of those already reaching 10* is significantly above 70. Roughly, the older you get, the more on the high side of the distribution you're likely to be, simply because you survived the low end of the distribution. Those who are already 50 have a better chance to be 90, on the average, than those just born.
The results are potentially interesting, though I'm initially skeptical of *any* measurement of phenomena back at this redshift claiming accuracy to some tiny fraction of a percent. And, to be picky, astronomers virtually never say that an object is "12 billion ly away" --- we usually refer to their "location" via the redshift number, as this is easy and unambiguous.
But a change in the ratio of their masses might shed some light on exactly what mass is to begin with. Yes, it's the ability to curve space, and also the resistance to being accelerated. But never mind the p/e ratio being fixed, no one really understands why the individual values are what they are to begin with.
For example, something that always gets me is the muon. Identical to the electron in virtually every way (charge, apparent point-like non-structure, lepton) except is has a mass roughly 207 times as great. Why? What does it have 207 times more of than the electron does to make it 207 times more efficient at curving space? What kind of goo is there that makes it 207 times more resistant to acceleration? And if it's truly a fundamental particle, as we suspect for leptons, why 207-point-something?
Oh man, I'm seriously off-topic, but that was about the best 22-minute cartoon I've *ever* seen, save *maybe* for the Michigan J. Frog Looney Tunes episode. Glad there's at least one other Cheese-head.
Slashdot Mirror
In recent studies of deuterium in the galaxy, they're finding less than 1/25th of what they're expecting
According to the article, it's as much as 15% less than they were expecting. Not sure where 1/25 came from.
and almost entirely in the wrong places.
I don't know what you mean by "wrong", but if it's wrong for some isotopes to be trapped in grains, then a lot of them are in the "wrong" places. This has been supposed before, but I don't think anyone has detected it before now.
They therefore conclude that there must be MORE than what they expect, but in a place/form that is invisible.
You misread the article. This additional deuterium in the grains *gives* us more than we expected. Perhaps the nuclear reactions in some stars, or the rate of dredge-up before they eject their material, is somewhat different than we currently believe. Also, it is well-known that primordial material falls in on the disk of our spiral galaxy, so perhaps the rate of this infall is different (greater) from what used to be supposed.
Of course, we're all still probably idiots, so feel free to correct us after you're sufficiently amused by our floundering efforts.
By "not seen", we just mean that it doesn't *glow* like stars, not that it can't be detected at all. In fact, we detect it by the gravitational influence it has on neighboring luminous matter as well as lensing the light of background objects. We can study its large-scale nature and distribution fairly well, just not the composition or small-scale structure yet.
IAAAstrophysicist, so perhaps a good chunk of my brain has been consumed already, but are you certain you mean *deuterium*? Is there a cite for this? I worked on galactic chemical evolution, and I'm a little out of touch with recent developments in the field, but this is news to me. Or maybe we're all really as dumb as you think we are.
There are 4 inner planets, with similar properties and formation histories. There are 4 outer planets with similar properties and formation histories. Pluto belongs with neither, but has the most in common with what are now known as Kuiper belt objects. More and more of these are being found, some with supposed sizes greater than Pluto. One suggestion that, in my opinion, is the most reasonable is to recognize the 4 inner planets, 4 outer planets, and recategorize Pluto into the Kuiper Belt clan. Over and over in science, our first shot at categorizing things turn out to be unoptimal until we learn more about them. Recategorizing happens all the time as we learn more than merely superficial details about objects.
What is potentially troubling with this, and why I am skeptical of the implications for the Hubble constant, is that the age of the Universe had been narrowed down with a decimal point to 13.7 billion years, which means that the uncertainty in that number is +-100 million years or so. This is completely outside of the error bars. And the previous number had been honed in upon by not just the WMAP microwave background probe, but by many independent observations of Type Ia supernovae. It seems more likely to me that there is a systematic effect affecting the brightness of this binary star system observed in another galaxy than a confounding problem with WMAP or Type Ia. Also, it's a little odd to me to make Hubble constant inferences from a galaxy in our Local Group --- a galaxy that, together with Andromeda, is gravitationally bound to us (moving towards us) and doesn't obey the Hubble flow.
So what's wrong with the original statement? Seems all right to me. Events that happened when the universe was 1 million years old are indeed at (about) a redshift of 1000, and the redshift is just telling us the expansion of the scale factor (size) of the universe, so any distance back then has expanded by the same factor of 1000.
That imagery, since it has recently happened to actual people, is a little too disquieting to be tossed off as an innocent hyperbole.
But anyway, speaking downwind from a physics Ph.D., I have to say that I recall my grad school days as the best of my life. I'm a professor now, but if there was any way to actually raise a family and live on grad school fellowship/TA pay, I'd do it in a heartbeat. I got to hang around really interesting and smart people, think all day about fundamental physics and astronomy, conduct research and collaborate with the foremost experts in the world, be immersed in a collegiate atmosphere --- sports games, theater, international lecturers, beautiful campus. It's hard to imagine a more fufilling life from day-to-day.
I think the real litmus test is, "do you love your field?"
Only at pretty low redshift, though. At any redshift appreciably close to or greater than 1, there really isn't much meaning to "distance" --- would you interpret that distance to be at the time of emission, the time of detection, or somewhere in between? We basically just use the cosmological redshift, which says that the redshift z represents how much the universe has expanded since the radiation was emitted. That's it. Any "distance" or lookback time is model-dependent. Instead of measuring slight deviations in universal constants, they are perhaps measuring perturbations in a particular cosmological model.
In other words, the distance of the quasars -- and the frequency their light "should" be -- are highly model-dependent.
Right --- I'm just picking nits, since I've seen lots of confusion by others in similar reports.
Yeah, and you forgot that "pwned" isn't really a word!
No, "everyone" is a singular identifier. Jeez, and I'm not even a grammar nazi --- just out for some karma to burn.
Everyone has his favorite drink
Yeah, like grammar! Schwing! You just got nocked off the shelf and pwned!!one!
I suspect hogwash, but the statement that "something is defiantly up" [sic] made me laff. It's richly poetic.
Maybe --- I'm not sure of the requirements. But I'd think that even the $100 laptop has a fast enough processor to do web requests. And as for easier, it's not clear, since one advantage of Google's system is the portability of one's data across a number of machines that may be community-owned. I'm even thinking in education, it's easier to post a spreadsheet for students to enter answers or data than manage lots of independently-made spreadsheets, and that data is immediately amenable to statistical analysis.
Yep, I think there's more to this than the myopic view of the American market. As a greater share of the world comes online, this will basically commoditize MicroSoft's software and shove it into a niche market. A very large percentage of average users would appreciate an easy, free spreadsheet they can access from anywhere and share with anyone else, including schools and nascent community internet centers in developing parts of the world. Maybe Google is really thinking globally and long-term. In 5 years it really could be the dominant method of casual information exchange.
I'll put in a plug for Animation Master. I use it for 3D animation, but I've seen some good examples of 2D animation and "cut out" paper-doll type stuff done with it, too. It's a really good package for $299 ($199 educational).
Assuming the above is accurate and not hyperbole, it sounds like a slam-dunk case of wrongful termination, even if he had a *bad* lawyer, and your friend might even come through with quite a bit of cash. It's too bad you're accommodating those who would cheapen scientific education here in the US by not fighting their culture of fear.
..."any rebroadcast or retransmission of this program, without the expressed written consent of Major League Baseball, is strictly prohibited." And it's not limited, of course, to MLB.
Yep. For example, my students in physics and engineering will occasionally use Excel for fairly simple numeric computations --- figuring out dynamics from equations of motion, and so on. It's perfectly ligitimate to have 100,000 - 500,000 time steps for accuracy.
Very few places? We can see SN and blue compact galaxies down to redshifts of around 10, and can clearly see the CMB at a redshift of about 1100. Those are certainly cosmologically significant. What objects would you *like* to see?
Now we are finding some crazy shit. Stuff doesn't move the way it is supposed to. The crazy double super secret invisible "cosmological constant" and "dark matter" sound more to me like modern day epicycles than actual scientific theory. The scientific community does not like people who rock the boat, because they like to be right. Competing theories are pushed to the wayside, and something as innocent as sugesting that this universe or a universe existed before us and may have caused what we see today is contriversial.
Now that's just crazy. It's clear you're not a scientist. I remember when Perlmutter gave his initial SN indications of an accelerating expansion, he was met with wild derision at the conference I was attending. Astronomers (and physicists) *love* to prove each other wrong. New and bizzarre theories are rightly derided until they can stand up to the same level of rigor and evidence as the rest of the body of knowledge. It's clear now, after many more candidates have been observed, that Perlmutter was right.
could be wrong about things like the cosmoligical constant and dark matter or any other crazy theory I have in my head. My problem is that there are very few healthy debates on any of these untouchable theories. What debates that do occur can jeopardize dissenters' positions and funding. Now is not a good time for science in my view.
I strenuously disagree. All these cosmological mysteries make this a real Golden Age of astronomy. There are *many* healthy debates in the community and at the meetings, and most clearly and obviously in the current literature. Saying that dissent can jeopardize funding is absolute hogwash.
Since stars are basically point-like sources, they are prone to diffraction spikes caused by the telescope hardware itself. It's especially apparent when they are overexposed to enhance background objects. Typically the spikes are diffracted images of the supports for the secondary mirror of the scope.
It's not that the statement isn't literally accurate, but that, reading in context, his father was using the word "theory" in a diminutive sense and not as scientists use it.
Just catching up --- I think this is wrong. Life expectancies are a measure of how long, on the average, one expects babies born in a certain year to live. Extrapolating backwards is a wrong thing to do, because life expectancy generally goes up the longer one lives, since the mitigating statistics of childhood death have passed. Whereas one may be born with an expectancy of 70 years, after one successfully reaches 10 the average expectancy *of those already reaching 10* is significantly above 70. Roughly, the older you get, the more on the high side of the distribution you're likely to be, simply because you survived the low end of the distribution. Those who are already 50 have a better chance to be 90, on the average, than those just born.
But a change in the ratio of their masses might shed some light on exactly what mass is to begin with. Yes, it's the ability to curve space, and also the resistance to being accelerated. But never mind the p/e ratio being fixed, no one really understands why the individual values are what they are to begin with.
For example, something that always gets me is the muon. Identical to the electron in virtually every way (charge, apparent point-like non-structure, lepton) except is has a mass roughly 207 times as great. Why? What does it have 207 times more of than the electron does to make it 207 times more efficient at curving space? What kind of goo is there that makes it 207 times more resistant to acceleration? And if it's truly a fundamental particle, as we suspect for leptons, why 207-point-something?
It nags at me.
Oh man, I'm seriously off-topic, but that was about the best 22-minute cartoon I've *ever* seen, save *maybe* for the Michigan J. Frog Looney Tunes episode. Glad there's at least one other Cheese-head.