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BOSS: The Universe's Most Precise Measurement

Unknown Lamer posted more than 2 years ago | from the you-are-a-meaningless-dot dept.

Space 128

Cazekiel writes "Observing the primordial sound waves created 30,000 years after the Big Bang, physicists on the Baryon Oscillation Spectroscopic Survey have determined our universe's most precise measurements: 13.5 billion years old. The article detailing the study reports: '"We've made precision measurements of the large-scale structure of the universe five to seven billion years ago — the best measure yet of the size of anything outside the Milky Way," says David Schlegel of the Physics Division at the U.S. Department of Energy's Lawrence Berkeley National Laboratory, BOSS's principal investigator. "We're pushing out to the distances when dark energy turned on, where we can start to do experiments to find out what's causing accelerating expansion."'"

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Well (1, Funny)

Shai-kun (728212) | more than 2 years ago | (#39624807)

...like a boss.

Setting a new standard. (1)

pushing-robot (1037830) | more than 2 years ago | (#39624881)

The scale of this survey is really quite incredible. It will serve as a benchmark for other accomplishments for years to come.

For example, I just made a remarkably roundabout pop culture joke...

Re:Setting a new standard. (1)

Shai-kun (728212) | more than 2 years ago | (#39624939)

And using these new measurements, we can determine *exactly* how roundabout it is!

Re:Well (1)

an unsound mind (1419599) | more than 2 years ago | (#39626993)

Scientists: The universe's most productive pun machine.

Re:Well (0)

Anonymous Coward | more than 2 years ago | (#39627845)

Except, the rest of the universe rolls their eyes and change the subject

BOSS is the most precise? (-1)

Anonymous Coward | more than 2 years ago | (#39625041)

Aww hell. Mine thinks I'm a douche.

Born in the Big Bang (2)

tomhath (637240) | more than 2 years ago | (#39625099)

Isn't Slashdot supposed to be News For Nerds? Oh wait, it probably doesn't get any more nerdy than this. Good stuff.

Of course. (-1)

Anonymous Coward | more than 2 years ago | (#39625171)

My boss is never wrong, or so he keeps telling me.

Unknown lamer: please re-read article (3, Informative)

Ralph Spoilsport (673134) | more than 2 years ago | (#39625189)

It says the universe is precisely 13.75 billion years old, not 13.5 billion years old.

Re:Unknown lamer: please re-read article (5, Funny)

Jason Levine (196982) | more than 2 years ago | (#39625659)

The Universe may be 13.75 billion years old, but it doesn't look a day over 13.5 billion. I wonder if it's had work done. Maybe some cosmic surgery to reduce those time-space stretch marks.

Re:Unknown lamer: please re-read article (0)

Anonymous Coward | more than 2 years ago | (#39626773)

Maybe some cosmic surgery to reduce those time-space stretch marks.

I see what you did there, you removed E.T. from the universe. What did he ever do to you?

Re:Unknown lamer: please re-read article (0)

Anonymous Coward | more than 2 years ago | (#39628603)

Yes, I heard he got in touch with this guy who created this stuff called Dark Energy.
Just spread it on and even in 13 billion years you'll still look as young as ever.

The only problem is it they still haven't made a cream to deal with all those moles.

According to my own calculation ... (1)

Taco Cowboy (5327) | more than 2 years ago | (#39626081)

It says the universe is precisely 13.75 billion years old, not 13.5 billion years old.

... the universe is actually 13.74892103652974083 billion years old, and counting ...

Re:According to my own calculation ... (1)

mikael (484) | more than 2 years ago | (#39628329)

I imagine there is a cloud of interstellar gas sonewhere which displays the current capacity of the universe like one of those online data storage companies.

Re:Unknown lamer: please re-read article (2)

pgn674 (995941) | more than 2 years ago | (#39626373)

It says the universe is precisely 13.75 billion years old, not 13.5 billion years old.

Actually, you're both wrong. What you read is a link to a different, unrelated article that's 2 years and 2 months old [discovery.com] . I looked at the articles and papers [sdss3.org] , and I don't think any claim about the age of the universe is ever made.

I think this is instead the most accurate measurement of the distance between here and very far away galaxies, and of the distances between those galaxies. But I may be wrong on that. RTFA

questionable units (1)

mspring (126862) | more than 2 years ago | (#39625225)

I always try to get my head around the meaning of measuring something in units which didn't exist then.

Re:questionable units (1)

amRadioHed (463061) | more than 2 years ago | (#39626101)

Why? Would you also say it's questionable to measure the pyramids of Egypt in meters?

Re:questionable units (1)

mspring (126862) | more than 2 years ago | (#39626291)

No, that's different. The meter and the pyramids do exist simultaneously.

Re:questionable units (1)

superdave80 (1226592) | more than 2 years ago | (#39626743)

The universe existed before the unit of time 'years' existed.

The universe and years exist now.

The pyramids existed before the unit of time 'meters' existed.

The pyramids and meters exist not.

Re:questionable units (1)

dudpixel (1429789) | more than 2 years ago | (#39626991)

huh? so I guess the pyramids that are still around are fake? you been watching too much "despicable me" lately?

Re:questionable units (1)

superdave80 (1226592) | more than 2 years ago | (#39627557)

Doh. The last sentence should be 'now' instead of 'not'.

Re:questionable units (0)

Anonymous Coward | more than 2 years ago | (#39626717)

You measure the pyramids in football fields, not meters. Alternatively, you can measure the volume of the pyramids in Volkswagens.

Re:questionable units (1)

Sneeka2 (782894) | more than 2 years ago | (#39626929)

If you mean to say that the sun and the earth didn't exist back then and that hence the "year" didn't exist, then that's nonsense. A "year" is a somewhat well defined length of time, which applies just as much now as it did then, regardless of when that length of time was first defined or when the ingredients for defining it came into existence.

Now, if you'd be talking about whether the length of time we define as a "year" nowadays is the same now as it was back then, and whether time is a universal constant at all throughout the universe... you may be onto something.

Re:questionable units (0)

Anonymous Coward | more than 2 years ago | (#39628177)

> A "year" is a somewhat well defined length of time

Oh is it? Rather inappropriate I find to measure the age of the Universe as a function of some revolving of turds in the middle of nowhere xD

It turns out that this unit has been abstracted a bit, and precisely defined, it seems. A recursive definition, by the way:

http://en.wikipedia.org/wiki/Year [wikipedia.org]

In astronomy, the Julian year is a unit of time, defined as 365.25 days of 86400 SI seconds each.

http://en.wikipedia.org/wiki/Second [wikipedia.org]

[... here be really complex definitions ... and then this picture which pictures the picture very well indeed. Is this mess of wires and the two boxes lying on the floor that give authoritative answers about the length of a second, and ultimately, a year xD...]
        http://en.wikipedia.org/wiki/File:FOCS-1.jpg [wikipedia.org]

Very well then, have a nice day! -- sorry but I couldn't resist; what the fuck is a day, anyway? http://en.wikipedia.org/wiki/Day [wikipedia.org]

Re:questionable units (0)

Anonymous Coward | more than 2 years ago | (#39628763)

In what way is the definition recursive?

A second is given by a number of oscillations of the light emitted by a particular transition in a particular isotope of caesium. A bit arbitrary, perhaps, but as good a starting point as any. Then a year is 86400 seconds. What's recursive about that?

The problem with trying to make yourself look smart is that it's too easy to make yourself look like a jackass. Then again, we're posting on /. and I'm replying to you, so I guess I'm almost as big a jackass. Just not quite because I don't call things recursive which aren't recursive.

Recursion (0)

Anonymous Coward | more than 2 years ago | (#39628829)

See parent, then read this reply.

Re:questionable units (1)

BurningFeetMan (991589) | more than 2 years ago | (#39627057)

I'd mod you up, but my mod points currently don't exist. :(

So? (1)

dutchwhizzman (817898) | more than 2 years ago | (#39627793)

If they don't exist, do your mod points really matter at this time?

Re:So? (2)

webnut77 (1326189) | more than 2 years ago | (#39628841)

If a mod point falls in the forrest, does anyone get karma?

Re:questionable units (0)

Anonymous Coward | more than 2 years ago | (#39628201)

It's a pity there isn't a -1 Retard or I'd be very happy to throw that at him.

Re:questionable units (0)

Anonymous Coward | more than 2 years ago | (#39627529)

By that reasoning, no unit of time existed for the majority of those 13.5 billion past years. Units of time are a rather recent development.
Are you saying we can't express time at all for any span before a few of thousand years ago?

Another "It answers everything" report... (1, Interesting)

s.petry (762400) | more than 2 years ago | (#39625233)

While this project may yield a lot of data it still won't be able to answer most of the fundamental questions. I know they have to advertise that way in order to receive sponsorship and grants, but dang it I'm tired of hearing it.

We still won't have a clue about what Dark matter is, or even if it exists. It's still a hypothesis that makes big bang models work and gives us the idea that we understand gravity.

We still won't know what the Universe was just before the big bang, or what caused it.

Cool, but I'll ignore the hype.

Re:Another "It answers everything" report... (0)

Anonymous Coward | more than 2 years ago | (#39625385)

[snip]

We still won't have a clue about what Dark matter is, or even if it exists. It's still a hypothesis that makes big bang models work and gives us the idea that we understand gravity.

[snip]

We know something exists that causes a gravitational field. We call it "dark matter" because it causes gravity and doesn't reflect/emit light. It's gravitational field can be measured by light deflection - aka gravitational lens.

Re:Another "It answers everything" report... (1)

Bengie (1121981) | more than 2 years ago | (#39625753)

Dark Matter is the mysterious gravity, but Dark Energy is the repulsive force that they speculate is causing us to drift apart. From what I understand and read, Dark Matter is about 100% certain, but Dark Energy is closer still to a hypothesis.

Re:Another "It answers everything" report... (3, Interesting)

Rei (128717) | more than 2 years ago | (#39626183)

Personally, I like to view the expansion of the universe as simply a reduction in the Planck length/time relative to C. This would create the perception of a force pushing everything apart (light taking increasingly long, in terms of Planck units, to travel from one point to another). Ultimately, it's just a different perspective on the same thing, but I like it because it doesn't require the conception of some sort of mysterious "dark energy" -- just an explanation of why the Planck length would slowly shift.

And I find that, too, rather simple to envision, in a number of ways. For example, one that I've been thinking about recently is that if you view the universe in terms of information processing, the distance-limited interactions like the strong force decline in frequency as the universe ages. So if there's a fixed "processing power" of the whole universe but a decreasing number of "calculations" per "unit" time, then the number of steps per "unit" time increases, which could be expressed in any number of ways toward the universe's physical constants.

Re:Another "It answers everything" report... (2, Interesting)

Anonymous Coward | more than 2 years ago | (#39627297)

If the Planck length were changing with respect to c, such that Planck's constant was changing with respect to c, you would be seeing the effects of changes to things like the fine structure constant and Rydberg constant, which would easily be visible spectroscopically over great distances.

Re:Another "It answers everything" report... (1)

Spinalcold (955025) | more than 2 years ago | (#39627913)

interesting way of wrapping your head around it. I think of vacuum energy and its probably just as wrong (not to say you are wrong conceptually, when it comes to far out physics it gets harder and harder to conceptualize what it is). I can make myself more comfortable with vacuum energy than changing planks constant. Though that's a little bias since that's my favorite of all physics discoveries.

Re:Another "It answers everything" report... (0)

Anonymous Coward | more than 2 years ago | (#39628183)

"doesn't require the conception of some sort of mysterious "dark energy" -- just an explanation of why the Planck length would slowly shift."

Yes, it just requires an explanation - which puts in in the same spot where the dark energy working hypothesis is.

Do you exclude the possibility that the cause for your Planck scale idea involves an as of yet unknown force or energy?

"Dark energy" is no more than a name for whatever it is that causes the cosmological expansion effects that are observed. It's just a label to refer to that still unknown cause.
The idea that it is a force or energy, is - although thought to be one of the more promising directions - only one of several possible directions under investigation.

Re:Another "It answers everything" report... (1)

Pino Grigio (2232472) | more than 2 years ago | (#39627915)

Actually I think "Dark Energy" is not so much a hypothesis; it does have observational evidence to support it. It's not "stuff" as such, more the energy in empty space. I've just finished reading Lawrence Krauss's book, A Universe From Nothing. It's an excellent book and I highly recommend it to get a understanding of the basics.

Re:Another "It answers everything" report... (1)

oreaq (817314) | more than 2 years ago | (#39628477)

Dark Energy is the repulsive force that they speculate is causing us to drift apart

While technically true, that's kind of a wag the dog view of the universe. We observe that all the other galaxys are not only flying away from us, they are getting faster. According to our current understanding of nature this acceleration must be caused by some kind of force and this force must be "fed" by some kind of energy. We call this energy "dark energy". It's not a speculation that dark energy causes the acceleration, it is the definition of the phrase "dark energy".

Dark Matter is about 100% certain, but Dark Energy is closer still to a hypothesis.

The situations for dark matter and dark energy are practically the same. The visible matter doesn't cause enough gravity to hold galaxys together. Again, according to our current understanding of nature there must be another source of gravity other than visible matter. We call this source of gravity "dark matter".

Both, dark matter and dark energy are "speculative" in the same way. Both start with relativity as our current model of gravity. We know that relativity is wrong, i. .e. it's predicition contradict observations but it's the best model we got so far. If somebody comes up with a better model for gravity than relativity and that new model doesn't require dark energy or dark matter to make correct predicitions then we can remove both from our models.

Re:Another "It answers everything" report... (1)

Man On Pink Corner (1089867) | more than 2 years ago | (#39625715)

In other news, the Universe still doesn't owe you an accounting of itself. Ric has more at 11.

Re:Another "It answers everything" report... (0)

Anonymous Coward | more than 2 years ago | (#39626523)

"Dark Matter" ranks up there with "the world is flat" in terms of stupidity.

Dark matter is just regular matter that doesn't happen to emit light. It's just regular plain old matter.

Fucking dumbass scientists brainiacs.

Re:Another "It answers everything" report... (0)

Anonymous Coward | more than 2 years ago | (#39627249)

Maybe you should read up on what dark matter is, with observations showing most of it to be non-baryonic and not interacting with electromagnetism (which is a stronger constraint than just not emitting light). Or you could just keep attacking nonexistant, strawman theories, in which case you should maybe consider complaining about Eratosthenes' flat earth theory next.

Re:Another "It answers everything" report... (0)

Anonymous Coward | more than 2 years ago | (#39628865)

Give me a break, all the research is theoretical and based on guesswork. They have no idea what it is and Occam's Razor says it's just regular matter that is difficult to measure.

Re:Another "It answers everything" report... (1)

ceoyoyo (59147) | more than 2 years ago | (#39627449)

Wait, you're complaining that this project is overhyped because it doesn't claim it will answer questions like what is dark matter or what happened before the big bang?

dude (0)

laserdog (2500192) | more than 2 years ago | (#39625259)

good job man u found out how to tell how old the universe is wheres my flying car and space colonys

Slashdot brings you another unparseable summary! (1)

wonkey_monkey (2592601) | more than 2 years ago | (#39625273)

Come on, what is this supposed to mean?

physicists on the Baryon Oscillation Spectroscopic Survey have determined our universe's most precise measurements: 13.5 billion years old

Is "13.5 billion years old" the measurement (singular, not plural as the summary says)? Or are the measurements they have measured 13.5 billion years old, whatever that means?

Re:Slashdot brings you another unparseable summary (2, Funny)

Anonymous Coward | more than 2 years ago | (#39625447)

Obviously it's saying that no-one in the entire universe has ever measured anything to more than three significant figures.

Title backwards and such (2)

FrootLoops (1817694) | more than 2 years ago | (#39625327)

The title meant to say "BOSS: The Most Precise Measurement of the Universe". The other way round can mean these measurements are the most precise ever, which isn't even remotely true. For instance, the article says, "BOSS gives that distance to within 1.7 percent", whereas (to pick something out of a hat) the fine-structure constant has been measured to a precision of less than one part in a billion or within less than 0.0000001%.

Maybe a physicist can chime in here--how is the red shift actually measured in an experiment like this? You could of course measure the wavelength of incoming light, but how do you know what the wavelength "should" be? Are there some common spectral lines one can look for?

Also, is there any practical use to this experiment? I'm fine with pure research, but I was curious if maybe some of the techniques find application elsewhere. The article didn't mention any.

Re:Title backwards and such (0)

Anonymous Coward | more than 2 years ago | (#39625479)

Yes, there are lots of spectral lines where you know the rest frame wavelength quite accurately. So it's a pretty trivial matter to measure the redshift to about 0.1%.

There are pretty much zero practical uses to this measurement.

Re:Title backwards and such (0)

Anonymous Coward | more than 2 years ago | (#39625521)

Yes, there are plenty of spectral lines that are considered. I'm not in observation so I don't know exactly which they look at - frankly, any they can get a handle on, but particularly I'd imagine Lyman alpha, and I think some iron lines are very strong too though that might be a brain fart. Once you've got spectral lines to hang from, measuring the redshift is in principle very easy -- point a spectrometer at the galaxy and measure it. Simple. Unfortunately to actually *do* that with a survey the size of the SDSS-III is totally impractical, so instead of spectrographic redshifts they use *photometric* redshifts, where the redshift is estimated from the intensity of the galaxy seen through different filters. That probably sounds really loose and woolly but it's a statistical measure, not precise, and it's tested for large subsets of the full sample to calibrate it properly, and to quantify errors the technique introduces. Photometric redshifts aren't ideal, but they're a necessary evil - and since the errors are well tested, they can be controlled.

Re:Title backwards and such (0)

Anonymous Coward | more than 2 years ago | (#39625905)

While you're right that photographic redshifts are easier to obtain, BOSS *is* primarily a spectroscopic survey. Something like 1.7 million *spectroscopic* redshifts will be obtained by the end of the survey (see http://www.sdss3.org/surveys/boss.php ), and those are the redshifts being used for the analysis linked above.

Re:Title backwards and such (0)

Anonymous Coward | more than 2 years ago | (#39625809)

Maybe a physicist can chime in here--how is the red shift actually measured in an experiment like this?

I'm an astronomer. I don't work with redshifts myself, but the guy sitting next to me does.

But anyway - you already figured out the right answer. There are absorption lines in the spectra of these objects, and the amount that they're displaced from their usual wavelengths tells you what the redshift is. If you see a single spectral line, you don't know which one it is - but when you see a bunch of them, with the correct spacing between them, you can usually figure it out.

Take a look at the last plot on the article page [sdss3.org] . The horizontal axis is wavelength; the vertical axis is brightness. The vertical grey lines, with labels like "MgII" and "Hb" are the positions of the spectral lines for (in this case) magnesium ("Mg") in its second excitation state ("II"), and one of the (I guess) hydrogen-beta lines. Notice that, at least for some of them, the orange plot shows a dip as it passes that wavelength.

Re:Title backwards and such (0)

Anonymous Coward | more than 2 years ago | (#39625889)

Redshift is broadly used all over astrophysics and to a lesser extent in terrestrial applications. Generally you're working with data that's a bit easier to manage and typically you only have the one spectrum - e.g. of a star or another emission source. We know enough nuclear physics to predict a lot of transition lines, so it's just a matter of lining up what you see to the expected stationary spectrum. Generally for high precision work you'd take an average (roughly speaking) over as many lines as you can identify.

In terms of knowing what the wavelength should be, well it boils down to E = (hc/wavelength) and knowing the energy levels of the atom or molecule which can be calculated via quantum mechanics (it gets tough after Hydrogen, but computers will do it). After that there are databases of standard emission lines that you can use, I assume they're continually added to as more and more complicated molecules are analysed, but for a low resolution spectrum we can identify virtually everything these days.

Besides velocity calculations, the obvious interest is actually looking at what's in a sample and this is spectroscopy 101. You look at what's being emitted and absorbed and you can tell what the thing you're looking at is made of.

Re:Title backwards and such (1)

aardvarkjoe (156801) | more than 2 years ago | (#39626475)

Even discounting the title, I can't parse the first sentence of the summary in any way that makes sense. I suspect that the summary was trying to say that they've precisely measured the age of the universe as 13.5 billion years (which isn't even right, according to the linked article).

Maybe Unknown Lamer is CmdrTaco coming back in disguise!

Re:Title backwards and such (1)

FrootLoops (1817694) | more than 2 years ago | (#39626627)

Yeah, it's a lame sentence. I forgot to criticize it in my haste to read the article and figure out what it might mean. I'm pretty sure the submitter just misunderstood the Discovery article. It uses the phrase "most precise measurements ever made" in the first paragraph and has a link to "ANALYSIS: The Universe is Precisely 13.75 Billion Years Old". Both say "precise", and a careless person might shove them together with a badly written sentence and a typo (13.5 instead of 13.75) to get the last half of the summary's first sentence. The 13.75 number isn't even from this study; the link was to a story from 2010 about a NASA study.

there's no such thing as a simultenaity (-1)

decora (1710862) | more than 2 years ago | (#39625339)

it's einstein's relativity 101. no event appears "simultaneous" to two observers moving at different speeds.

therefore there is no such thing as the 'beginning of the universe' common to all reference frames.

therefore the entire story summary is nonsensical.

Re:there's no such thing as a simultenaity (1)

Anonymous Coward | more than 2 years ago | (#39625409)

it's einstein's relativity 101. no event "appears" simultaneous to two observers moving at different speeds.

there fixed that up for you...

That would be like saying 'since I cant see it it didnt happen'...

Re:there's no such thing as a simultenaity (3, Informative)

Anonymous Coward | more than 2 years ago | (#39625467)

No it isn't, you're making a common mistake that people who pretend they know about physics make. Put it this way: leave the physics to the people who know anything about it and go back to masturbating over furry porn.

Cosmology is based on the Robertson-Walker metric. The Robertson-Walker metric contains an unambiguous time coordinate. Put an observer in that metric and, yes, they will observe a different time -- but if they're not to violate the symmetries of the metric, the differences will be at a perturbative level, which is to say unimportant. When they say "the universe is 13.7bn years old" they don't mean to say "the time measured along every worldline would give 13.7bn years", because to say such would be nonsense. What they mean that "the time measured in a frame comoving with the metric is 13.7bn years and to an approximation good up to redshifts of approximately z=1 and quite possibly significantly less this is an estimate that holds for all observers who haven't gone dallying with black holes".

Seriously, learn what the fuck you're talking about before you make yourself look stupid.

you mad bro? (1)

decora (1710862) | more than 2 years ago | (#39626015)

with the universe full of 'dark matter', how do any of us know that our bits havent been dallying with black holes?

Re:you mad bro? (0)

Anonymous Coward | more than 2 years ago | (#39626607)

Black holes and dark matter are two different concepts, so how is your statement supposed to make any sense?

Re:you mad bro? (0)

Anonymous Coward | more than 2 years ago | (#39628749)

it's a racist joke you dumbass

Re:there's no such thing as a simultenaity (0)

Anonymous Coward | more than 2 years ago | (#39626599)

You sound like you have something jammed up Uranus, big boy.

Re:there's no such thing as a simultenaity (0)

Proudrooster (580120) | more than 2 years ago | (#39625531)

Amen brother. Even in Einstein's own thought experiments regarding time, simultaneity doesn't make since (to me) either. When they say the universe is 13.5 billion years old, my question is by which watch are you measuring. Time dilation really, really bugs me. Why can't it just be the 'same time' everywhere at once. But yes, I agree, the article makes no sense and it just a headline grab. And I might say, a bit of an arrogant headline grab as they are seeking to define a universal clock constant where one does clearly not exist outside of your own inertial reference frame. There are other problems that I won't even go into, like the speed of light being a universal constant, the size of the universe, and the fact that we can supposedly see objects from distances where the light wouldn't have had enough time in which to propagate from. It is all just maddening. We need to find a way to get outside of the universe so we can study it. I think that making the measurements from inside the system will never ever work.

Re:there's no such thing as a simultenaity (5, Insightful)

Anonymous Coward | more than 2 years ago | (#39625603)

I'm sure that people who have studied cosmology, both theoretical and observational, in extreme depth, for a period of upwards of 20 years, are going to be devestated that "Proudrooster" and "decora" on Slashdot have shattered their entire field with a few brief sentences. Such a waste of man-hours! I'm sure the two of you will be quick to provide us with alternative models of cosmology and interpret them properly for the layman, causing no ambiguities in those who don't fully comprehend the fruits of your genius.

Seriously, "a headline grab"? This is the ninth data release of a massive project that's been going for more than twenty years since it was first planned in detail, it's been studied by hundreds of extremely well qualified physicists, astronomers and engineers, and is providing data for all of us in the field to use to test models which we construct, from which we extract observable parameters, and test against observation... and you think it's a fucking headline grab? You think it's arrogant? The mind fucking boggles.

Re:there's no such thing as a simultenaity (0)

Anonymous Coward | more than 2 years ago | (#39626289)

Boggle doesn't quite cover it - what is the hybrid between "boggle" and "WTF" ? maybe bogwf ?

Re:there's no such thing as a simultenaity (0)

Anonymous Coward | more than 2 years ago | (#39626677)

"bogthefuck".

Re:there's no such thing as a simultenaity (0)

Proudrooster (580120) | more than 2 years ago | (#39626535)

Ok.. I just updated Wikipedia. The Universe is now 13.5 billion years, it was at 13.7. Sorry for my skepticism. I also apologize for doubting that we mere mortals can measure cosmological constants from an unknown point in the universe of unknown size undergoing a mysterious accelerating expansion. :)

Re:there's no such thing as a simultenaity (0)

Anonymous Coward | more than 2 years ago | (#39626641)

I also apologize for doubting that we mere mortals can measure cosmological constants from an unknown point in the universe of unknown size undergoing a mysterious accelerating expansion

It helps to not be arrogant and stupid. But if you'll try harder next time, we will accept your apology.

Re:there's no such thing as a simultenaity (1)

FrootLoops (1817694) | more than 2 years ago | (#39626935)

Ok.. I just updated Wikipedia. The Universe is now 13.5 billion years, it was at 13.7.

Hah, that's extra funny considering the summary's 13.5 billion number came from misquoting the Discovery article's link to an older article (by another group even) titled The Universe is Precisely 13.75 Billion Years Old [discovery.com] . You and the submitter might hit it off nicely--you'd at least be able to talk about your remarkable lack of attention to detail.

I'm pretty sure you're joking about editing Wikipedia, but really you have no idea what you're talking about. Being confused by time dilation is for undergraduate physics majors. The world is unintuitive. You get over it after a while; all that matters is that you can make accurate predictions about it, and time dilation does not violate that ability no matter how much cognitive dissonance it causes you.

Re:there's no such thing as a simultenaity (1)

guspasho (941623) | more than 2 years ago | (#39627783)

You make it sound like it would be a noteworthy feat if someone attempted the task and had some measure of success.

Re:there's no such thing as a simultenaity (1)

jon3k (691256) | more than 2 years ago | (#39626401)

I assume that when the universe started there was only one reference point, the origin.

Re:there's no such thing as a simultenaity (1)

dissy (172727) | more than 2 years ago | (#39626697)

it's einstein's relativity 101. no event appears "simultaneous" to two observers moving at different speeds.

Ok, but we are discussing 10^87 observers that are all moving at the same speed (C)

therefore there is no such thing as the 'beginning of the universe' common to all reference frames.

Therefore if you start with proven incorrect assumptions, you will only get proven incorrect answers.

In Soviet Russia (0)

Roachie (2180772) | more than 2 years ago | (#39625519)

Boss measure YOU!

FAGORZ (-1)

Anonymous Coward | more than 2 years ago | (#39625527)

Primordial sound waves? (2)

PPH (736903) | more than 2 years ago | (#39625609)

Thought this was going to be about a Stones concert tour.

Never mind.

Re:Primordial sound waves? (2)

Ralph Spoilsport (673134) | more than 2 years ago | (#39626393)

considering they have Nosferatu on guitar, I wouldn't be surprised...

Nosferatu? (1)

dutchwhizzman (817898) | more than 2 years ago | (#39627797)

One does not simply play guitar in the Rolling Stones?

Re:Primordial sound waves? (1)

seandiggity (992657) | more than 2 years ago | (#39626995)

Thought this was going to be about a *Springsteen* concert tour.

TFTFY. The headline was "BOSS" :P

Years? (2)

Smiddi (1241326) | more than 2 years ago | (#39625685)

Why do we use years as time measurement for events that happen in the universe? Years are an Earth measurement that have no bearing on anything else in the universe.

Re:Years? (0)

Anonymous Coward | more than 2 years ago | (#39625723)

Gee, let me think. Maybe because it's a common measurement that's easy to understood? Would you prefer we gave you time in megaparsecs? Then the universe is just over 14,000Mpc old.

Cue the usual stream of Slashdot physics "experts" telling me that OOOH THE PARSEC IS A UNIT OF DISTANCE NOT TIME!!!!!!! Not if I set c=1; at that point the second is a unit of distance and the parsec is a unit of time.

Maybe you'd prefer we measured in some utterly absurd units -- feel free to propose them. Hey everyone! The universe is 17.5x10^65 fuckwits old!

Seriously, why did you bother with this comment? "Why do we measure in years?" Why the fuck not? I'm not going to measure in Planck times, for fuck's sake, and I challenge you to find any other unit of time that's even got a claim to being universal. But if you want to, go ahead. What you actually find if you look at cosmology is people will measure "time" in redshift, or in temperature -- and that temperature will be quoted in electron volts. Years are for visualisation.

Re:Years? (1)

guspasho (941623) | more than 2 years ago | (#39627769)

I was thinking the same thing. If you ask that sort of question, isn't it incumbent upon you to explain what terms we should be using instead, and also preferably why? Otherwise, you're just trolling.

Re:Years? (0)

Anonymous Coward | more than 2 years ago | (#39626639)

Why do we use years as time measurement for events that happen in the universe? Years are an Earth measurement that have no bearing on anything else in the universe.

Probably because it's easier than saying 2.90091201×10^17 oscillations of a cesium atom, and at this point in time all the intelligent life we know of is well acquainted with earth measurements.

(Forgive me if I messed up the math and that isn't the number of oscillations in a year)

Re:Years? (1)

quenda (644621) | more than 2 years ago | (#39626735)

Why do we use years as time measurement for events that happen in the universe? Years are an Earth measurement that have no bearing on anything else in the universe.

For the same reason you asked that question in English instead of a dialect from Flartibartfast IV.

Worst (0)

Boronx (228853) | more than 2 years ago | (#39626003)

Worst summary ever.

Re:Worst (1)

quenda (644621) | more than 2 years ago | (#39626753)

Worst summary ever.

Welcome to slashdot. I hope you stay a while.

yoU fail iFt... (-1, Redundant)

Anonymous Coward | more than 2 years ago | (#39626303)

To3el uNder the

more detailed info (1)

bcrowell (177657) | more than 2 years ago | (#39626319)

The press releases linked to from the /. summary are pretty thin. The Wikipedia article [wikipedia.org] is a lot better. Here are the two papers: [1] [arxiv.org] , [2] [arxiv.org] .

What's causing accelerated expansion? (1, Interesting)

KlomDark (6370) | more than 2 years ago | (#39626931)

It's pretty obvious, just people aren't thinking about it from the right mindset:

It has to do with the expansion of outer shell of the edge the remnants of the original big bang explosion; It's really a type of a 'less resistance' problem, like as if something like air resistance gets less as the perimeter of the expanding explosion moves out, yet the mass of the universe remains the same. [Although that explanation ignores the fact that there's not a whole lot of air in space, but bear with me.]

Although it's not a normal resistance issue like the basic effect of wind resistance, it is different but similar enough to make the full point of view as follows:

Sort of easy to describe using an analogy of a balloon inside of a large bell jar. Normally, when you blow up a balloon, the air pressure increases as the balloon expands, since it's the increasing air pressure inside the balloon which is causing the expansion.

But in this case, blow the balloon up halfway, tie it, and seal it inside of the bell jar. Now you sharply/quickly reduce the air pressure in the bell jar by somehow removing a volume of air that is just less than it will take to pop the balloon by over-expansion as the air pressure drops. (Not sure of the math to determine that amount, just would have to experiment with a few balloons to get it right. It's not important to get it at the edge of popping, it's really what goes on inside the balloon while it's being inflated so quickly, yet this time with air pressure decreasing rapidly as it expands rapidly.

  With the impetus coming this time from the outside of the balloon with the bell jar causing a sudden 'vacuum' (Violent loss of pressure actually, not a true vacuum.) implosion around the balloon instead of increasing the pressure on the inside of the the balloon. With the sudden change in outside air pressure, due to the elasticity of the air inside the balloon it would cause a donut-shaped compression wave to (Is there a word for three-dimensional equivalent of the act of traveling from the outer to inner rings of a set of two-dimensional concentric circles?) intensify as it shrank to a more and more compact size, then impacting itself as it reached the absolute center of the balloon, causing it to violently bounce as a shock wave radiating outward to the edge of the balloon, where it's energy would suddenly press against the edge (Yet the force of the sudden re-expansion will cause a 'vacuum ball' of lower pressure in the center of the balloon caused by the bounce causing a lot of air particles in the center to bounce out with the shock wave as they attempt to reclaim the natural equilibrium between air particles), causing it to expand a bit as the rubber/latex gives way a bit (Yet still not popping) and then de-expanding (starting to shrink) as the energy of the shock wave is spent fighting the elasticity of the balloon's edge and then loses.

Next we get it in reverse, and over and over until all the energy from that initial shock of 'vacuum' has been converted to friction/heat. But that entire process of bouncing is still not the part we are focusing on, but we're nearly to the end of this long explanation:

Now think of the particles of air inside the balloon, and how they would react as to their average distance between particles, both expanding and compressing. During the phase where the shock wave is expanding back out after it's first collision with the center, about halfway between the center and the edge of the balloon - the energy of the shock wave has already caused some of the inner air particles to begin traveling outward and gaining some inertia. While at the same time, the edge of the balloon is still rapidly receding as it expands due to the 'outer vacuum' of the bell jar still loosing pressure and 'sucking' the balloon larger.

So this sets the particles moving outwards, and if you do the math - all particles are moving away from each other at an increasing speed, just like the particles/energy of the universe are doing as it expands outwards from the core of the big bang explosion.

Re:What's causing accelerated expansion? (0)

Anonymous Coward | more than 2 years ago | (#39628353)

In the words of click and clack:
BOOOOOOOOOGUS

taking measurements... (0)

Anonymous Coward | more than 2 years ago | (#39627609)

like a boss

I find it hard to care (1)

gweihir (88907) | more than 2 years ago | (#39627629)

About something that was 8 orders of magnitude longer in the past than my own life expectancy. Well, I do not begrudge these people their intellectual exercise, I just hope they did not spend a lot of money on this irrelevant result.

Old news (1)

guspasho (941623) | more than 2 years ago | (#39627709)

"We've made precision measurements of the large-scale structure of the universe five to seven billion years ago"...

And they're just now getting around to telling us about it?

What the Bible says - contradicts YECs not science (0)

Circlotron (764156) | more than 2 years ago | (#39627775)

Many religious people will tell you the earth is only 6000 years old. To those I say have a look at what the Bible ACTUALLY says. It says that in the beginning the earth got made. Then it sat around for some *unspecified* time. Then and only then after that the SURFACE of the earth was made suitable for habitation in 6 chapters of time called "days". There could have been a bazillion years between the earth first appearing and the start of these 6 "days". In this regard the Bible does not contradict this measurement of the age of the Universe at all. What is does contradict is the erroneous views of many calling themselves Christians. Nothing new there, BTW.

Precision Measurements (1)

mikecornelison.com (2602143) | more than 2 years ago | (#39627833)

"We've made precision measurements of the large-scale structure of the universe five to seven billion years ago" - Sure took you long enough to get the news out.

it is not called measurment (1)

zugedneb (601299) | more than 2 years ago | (#39628089)

it is called ESTIMATION. they have ESTIMATED the age, not measured it...

Observing the primordial sound waves... WTF?!?! (0)

Anonymous Coward | more than 2 years ago | (#39628197)

> Observing the primordial sound waves created 30,000 years after the Big Bang

Oh dear! How do you picture those sound waves? By launching a bunch of microphones to the Moon? Has those sound waves been propagating 75 gazillion years through the dust and sparse molecules out there, reaching stars and ultimately the Earth for us to hear them?

Or were they half drunk on the beach with a tape recorder? Perhaps it's Neptune's Oceans that are 75 gazillion years old xD

Re:Observing the primordial sound waves... WTF?!?! (0)

Anonymous Coward | more than 2 years ago | (#39628811)

Are you trolling? Because if it's a genuine question, why the hostility?

Let's give you an answer.

For a start, I don't know what that 30,000 years is doing there. When the universe was 30,000 years old, yes, there were sound waves, but that's not what we see. We see the imprint of the sound waves as they were around 300,000 years after the Big Bang. But then, a witless typo in a Slashdot summary isn't much of a surprise these days, so let's let it ride.

OK, so the standard model of cosmology. The universe started off small - and, being small, it was much, much hotter. Simple conservation of energy tells you that. The universe is 75% hydrogen. We know that from observation, and can predict it if we postulate Big Bang cosmology. The binding energy of hydrogen is 13.7eV or thereabouts. So back in the past there was a time when the average photon had more than enough energy to keep hydrogen completely ionised. It turns out that hydrogen was completely ionised until the universe was roughly 300,000 years old. Before that time, the universe was small and absolutely filled with photons, protons and electrons, enough that you could most certainly describe them as a fluid. (Actually, you still can to a very good approximation, on the scales we're talking about.) The fact that photons constantly ionise hydrogen, then get reemitted when an electron condenses into a proton, and then reionise hydrogen again, coupled the three fluids tightly together in some odd cosmic game of billiards. Put simply, the protons would naturally want to collapse into gravity wells - produced by themselves, and produced by the dark matter that has nothing to do with the billiards game. So they do. But the photons are producing a radiation pressure tending to kick them back *out* of those gravity wells. This sets up sound waves -- the universe was ringing.

At 300,000 years, electrons condensed into protons to form hydrogen, and the photons could stream free. But left on the distribution of those photons is a print of the sound waves. No-one is pretending that sound waves are still propagating through the universe, but the mark of them is there on the photons. This is what we see on the microwave background. And this is what SDSS-III has measured, the imprint of the same sound waves, but on the galaxy distribution. Since we can predict the wavelength of the sound waves that existed before the photons free-streamed, we can track how that wavelength evolved. The great power of this result is that we now have three or four handles on it at different moments in time, so we can constrain the evolution of the universe even more tightly.

Expected Value Physics!! (0)

Anonymous Coward | more than 2 years ago | (#39628543)

EVP, not to be confused with Electronic Voice Phenomenon!

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