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Man-Made Atomic Clocks the Best In the Universe

timothy posted more than 4 years ago | from the take-that-you-buncha-pulsars dept.

Australia 267

An anonymous reader writes "The widespread belief by astrophysicists that pulsars and white dwarfs are the best clocks in the universe is wrong, say two Australian physicists. John Hartnett and Andre Luiten from the University of Western Australia have recently shown that man-made terrestrial atomic clocks take the crown, contrary to numerous claims in astrophysical literature that the natural timing provided by pulsars and white dwarfs is the most precise. The preprint of their paper, available on the arXiv, shows that terrestrial clocks exceed the accuracy and stability of the astrophysical 'clocks' by all sensible measures, in some cases by several orders of magnitude."

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Yeah thats right. (5, Funny)

celticryan (887773) | more than 4 years ago | (#31765806)

Man > Nature... Take that religion!

Re:Yeah thats right. (1)

Deflagro (187160) | more than 4 years ago | (#31765850)

Doesn't Man = Nature? :P

Re:Yeah thats right. (1)

AliasMarlowe (1042386) | more than 4 years ago | (#31766014)

Hey, don't freak out, man. It's like, always the right time.

Re:Yeah thats right. (1)

Eudial (590661) | more than 4 years ago | (#31766044)

Strictly speaking, as there are elements in nature that are not elements in man, but no elements in man that are not elements in nature; man is a subset of nature. There is a symbol for the relationship, but slashdot's unicode-fu is weak and fails to render it.

Re:Yeah thats right. (1)

dgatwood (11270) | more than 4 years ago | (#31766662)

Remarkably, Slashdot translates it correctly from the raw Unicode character into the ampersand notation (&#8834), but then strips it out going to HTML. It also fails to handle the named entity (⊂) and the hex version (⊂).

Re:Yeah thats right. (3, Funny)

interkin3tic (1469267) | more than 4 years ago | (#31766142)

Doesn't Man = Nature? :P

It depends on how you dispose of your waste.

Leaving it wherever: Nature
Flush: Man
Flinging it: Funny
Burying it in gravel: Nature, but with an air of superiority

Re:Yeah thats right. (1)

John Hasler (414242) | more than 4 years ago | (#31766430)

> Doesn't Man = Nature?

According to the Church, no.

Re:Yeah thats right. (1)

Deflagro (187160) | more than 4 years ago | (#31766484)

Probably why I don't go to church haha.

Re:Yeah thats right. (1)

garompeta (1068578) | more than 4 years ago | (#31766672)

machine > man
eventually...

Re:Yeah thats right. (0)

Anonymous Coward | more than 4 years ago | (#31766920)

Doesn't Man = Nature? :P

I thought it was Man = Religion...

Re:Yeah thats right. (2, Insightful)

Anonymous Coward | more than 4 years ago | (#31765934)

in dutch: hoogmoed komt voor de val.....

Religion is something man made, mostly based on something big that happened.... And at the moment they are mostly busy with child abuses, or blowing them selves up...

But saying that man made the best in the universe, without ever having left our solar system is a little bit naive...

Re:Yeah thats right. (2, Insightful)

Anonymous Coward | more than 4 years ago | (#31766088)

Headline is awfully closed-minded of us to proclaim. I'm sure an alien race has a clock far, far better than our primitive cesium-transition clocks.

Re:Yeah thats right. (2, Funny)

Gilmoure (18428) | more than 4 years ago | (#31766892)

Yeah, yeah, where's their patent submission?

Uh-huh, that's what I thought. Freakin' alien anonymous posters. Go back to Alienastistan or wherever you're posting from.

Re:Yeah thats right. (2, Insightful)

JWSmythe (446288) | more than 4 years ago | (#31767074)

    Ditto. I thought it was very egotistical of us to believe that in the entire universe, our way is best.

    There are 9 × 10^21 (9,000,000,000,000,000,000,000) stars in the observable universe. Many of the stars themselves are unobservable, but we can see them because they are part of a galaxy that is obviously far away, and appears as a faint dot in our sky. That's only in the 46 billion light years from our lonely rock in the cosmos that we can observe.

    The odds that there isn't another populated planet (or a few hundred thousand of them) is pretty slim. Some are likely to be as advanced as us. The possibility is there that some are more advanced. Or worse, they were more advanced but have long since died off, but their "perfect" clocks still exist and are still running.

    But hey, more power to 'em. If they want to declare us the winners, I won't argue. We're the best. Yea! Humans!

   

Re:Yeah thats right. (1, Offtopic)

maxume (22995) | more than 4 years ago | (#31766410)

Religion cares very little for nature, it is more about ideas of dead men.

Re:Yeah thats right. (0)

Anonymous Coward | more than 4 years ago | (#31766728)

Yeah, that's what the judeo christian tradition teaches actually. Man has dominion over the universe. The Universe was created for man's use.

So take that nihilistic humanism! And gravity. FUCK Gravity.

Re:Yeah thats right. (1)

Corporate Drone (316880) | more than 4 years ago | (#31766766)

Man > Nature... Take that religion!

LOL... I think religion would answer, "when you've created something from nothing, rather than simply measure something accurately, give us a call."

Re:Yeah thats right. (4, Informative)

BarryJacobsen (526926) | more than 4 years ago | (#31767062)

Man > Nature... Take that religion!

LOL... I think religion would answer, "when you've created something from nothing, rather than simply measure something accurately, give us a call."

To which man replies: "We created you, Religion, out of absolutely nothing!"

Re:Yeah thats right. (1)

Comatose51 (687974) | more than 4 years ago | (#31766990)

Pretty sure religion is man made too.

No competition here... (0)

Anonymous Coward | more than 4 years ago | (#31767122)

Yet, nature created man and used him as a tool to create a very precise clock. There's no competition here, really.

Hell yeah! (0, Flamebait)

boneclinkz (1284458) | more than 4 years ago | (#31765854)

Man wins again! WHERE is your GOD now?

Re:Hell yeah! (1)

Wyatt Earp (1029) | more than 4 years ago | (#31765890)

God is off playing with fusion that produces excess energy.

Re:Hell yeah! (1)

MentlFlos (7345) | more than 4 years ago | (#31765908)

Man wins again! WHERE is your GOD now?

Good question... I bet his watch was off by a few milliseconds so he missed the appointment.

Re:Hell yeah! (1)

JayJay.br (206867) | more than 4 years ago | (#31766154)

Please excuse the poor english.

A man walks up to God and says:
Oh God, since for you, the whole age of the universe means just a second,
As for you all distance in the galaxies is merely a small step,
As for you all money on Earth is just a cent... ...would you give me a cent?

God says:

- Just a second, please.

Re:Hell yeah! (1)

maxwell demon (590494) | more than 4 years ago | (#31766174)

He laughs at all those who think the pulsars are there to measure time.

Re:Hell yeah! (1)

slayer_ix (927649) | more than 4 years ago | (#31766402)

He's right behind you.

Re:Hell yeah! (1)

garompeta (1068578) | more than 4 years ago | (#31766702)

I'm within your potentiality

I hate to be condecending... (2, Interesting)

epiphani (254981) | more than 4 years ago | (#31765894)

But .. duh? I mean, there is a lot of stuff between these pulsars and us. Any change in the local matter density, nearby gravitational disturbances, and there is no reliable time out of a pulsar. We can't honestly think that there is no undetectable gravitational effects between us and every pulsar in the universe, do we?

Then again, I'm nowhere near being an astrophysicist.

Re:I hate to be condecending... (2, Interesting)

qoncept (599709) | more than 4 years ago | (#31766250)

I'm nowhere near being an astrophysicist.

I'm not either, so ... honest question. How does gravity affect light? How much matter is in space? Or, more specifically, in the space between Earth and pulsars visible on Earth?

Re:I hate to be condecending... (0)

Anonymous Coward | more than 4 years ago | (#31766340)

A black hole has enough gravity that it sucks in light.

Re:I hate to be condecending... (1)

maxwell demon (590494) | more than 4 years ago | (#31766778)

Black holes don't suck.

Re:I hate to be condecending... (2, Informative)

Lunix Nutcase (1092239) | more than 4 years ago | (#31766396)

How does gravity affect light?

For one thing it can bend light and create gravitational lenses [wikipedia.org] .

Re:I hate to be condecending... (2, Informative)

dbet (1607261) | more than 4 years ago | (#31766472)

How does gravity affect light?

The same way it affects everything else - except since photons have essentially no mass, the attraction is very weak.

Re:I hate to be condecending... (1, Funny)

Anonymous Coward | more than 4 years ago | (#31766508)

If you're genuinely interested, the subject is called general relativity and you can read about it in the science section of every bookstore. If you're just looking for a few paragraphs of info, JFGI

General Relativity Simplified (4, Interesting)

Roger W Moore (538166) | more than 4 years ago | (#31767000)

How does gravity affect light?

Strictly speaking it does not - it bends space-time and light travels on a straight line which looks bent. Think of it this way - you took off and flew in a straight line from Edmonton, Alberta to London, UK someone in orbit would see that you had actually flown a curved path on the surface of the Earth. Light is the same - it thinks it is following a straight line but when looked at from a different frame it appears as a curve.

Re:I hate to be condecending... (5, Funny)

still cynical (17020) | more than 4 years ago | (#31767094)

How much matter is in space?

Strictly speaking, all of it.

Re:I hate to be condecending... (2, Funny)

Deflagro (187160) | more than 4 years ago | (#31766318)

I prefer to be pedantic instead of condescending. hee hee :)

Relativity... (1)

LostCluster (625375) | more than 4 years ago | (#31765900)

Really, time accuracy depends on your frame of reference. You need to trust something as the "absolute truth" before you can start saying that something is off-the-standard, because its off THAT standard that you chose already.

As long as GPS, Cell phone networks, and TV channels are within a split second of each other, I'm fine.

Re:Relativity... (3, Informative)

Chris Burke (6130) | more than 4 years ago | (#31766156)

You need to trust something as the "absolute truth" before you can start saying that something is off-the-standard, because its off THAT standard that you chose already.

Aside from there being no privileged reference frame to say has the "absolute true time", this has nothing to do really with saying that it's exactly 4:20pm exactly when it should be 4:20pm.

The measure they're talking about is how much variance there is in the frequency of the pulses over time, and you can measure that without any 'standard' to compare to -- you're actually comparing the signal to itself.

As long as GPS, Cell phone networks, and TV channels are within a split second of each other, I'm fine.

They could all claim exactly the same time as each other, but if the method they use to track time is "x many events in a second", then if the event in question does not have a stable period then you'll eventually have to add/subtract a second from the GPS, cell phone, etc time.

But yeah, for the majority of practical purposes you don't need timing precision equal to that of a pulsar, much less better.

Re:Relativity... (1)

Gilmoure (18428) | more than 4 years ago | (#31766958)

My stove and microwave clocks are off.

Too much noise in pulsars (2, Informative)

Maximum Prophet (716608) | more than 4 years ago | (#31765912)

The authors say that basically there's too much noise in the pulsars. I just skimmed the article, but I didn't see anything that said why the pulsars are noisy, nor did they answer the question if that noise can be fixed, i.e. using a space based telescope (light or radio), or does the noise come from interstellar sources.

Re:Too much noise in pulsars (2, Interesting)

Locke2005 (849178) | more than 4 years ago | (#31766062)

I would assume because the dust cloud around the pulsar that remains from the supernova that created it is slowly spiraling back into it... changes in mass effect angular momentum.

Re:Too much noise in pulsars (1)

maxwell demon (590494) | more than 4 years ago | (#31766916)

I would assume because the dust cloud around the pulsar that remains from the supernova that created it is slowly spiraling back into it... changes in mass effect angular momentum.

Changes in mass don't affect angular momentum. However, due to conservation of angular momentum, changes in mass may affect the period of rotation, which is what is used as clock here. And of course, the dust cloud has angular momentum itself, which of course also adds to the angular momentum of the neutron star when it hits.

Re:Too much noise in pulsars (0)

Anonymous Coward | more than 4 years ago | (#31766160)

I didn't see anything that said why the pulsars are noisy

Here they did and they gave three references in case you want more details.

Contrasting with this universal and unchanging definition, the frequency of a natural astrophysical source is determined by some stochastically distributed initial period together with some additional processes that have occurred in the evolution of the star to its current observed rotational status. It is thus extremely unlikely that these natural pulsating sources could ever be the basis of an accurate time system (Riehle 2004; Matsakis & Josties 1996; Matsakis & Foster 1996).

Re:Too much noise in pulsars (1)

vlm (69642) | more than 4 years ago | (#31766692)

I didn't see anything that said why the pulsars are noisy

They're hot, and hot things are electrically noisy. Once they cool to say 20K they'll be quiet, but too cool to detect. They do not transmit a perfect carrier wave with zero phase noise. Heck that's pretty hard for us on the earth to do a "good enough" job much less make a signal cleaner than can be measured.

They're electromagnetically active, and theres junk surrounding them that messes with them. aka "unknown localized source"

There's a lot of "stuff" in space between us and them moving at different directions, speeds, and densities to refract thru, and its constantly changing over time. AKA "scattering medium with variable optical depth"

Our ionosphere totally screws with RF, but I assume they're correcting for that.

There's at least 20 years of interesting scientific papers out there.

Relatively speaking... (5, Funny)

Hatta (162192) | more than 4 years ago | (#31765924)

Isn't the best clock going to be one in your frame of reference?

Re:Relatively speaking... (1)

PCM2 (4486) | more than 4 years ago | (#31766600)

Either that, or time itself is an illusion...

Re:Relatively speaking... (1)

Chris Mattern (191822) | more than 4 years ago | (#31766852)

Lunch time doubly so.

(couldn't resist)

Re:Relatively speaking... (0)

Anonymous Coward | more than 4 years ago | (#31766928)

Lunchtime doubly so.

as they say in pool...that's a lot of green (0)

Anonymous Coward | more than 4 years ago | (#31765962)

think about all of the gravitational anomalies which could abide between us and the nearest TIMEX pulsar and how that could pervert the ticks/tocks.

it really is better to have a closer in scale and closer in distance..."clock".

Definition is the Key (1)

alexj33 (968322) | more than 4 years ago | (#31766070)

Whatever the measuring stick is for "minute" and "second", that's the most accurate clock, by definition.

Re:Definition is the Key (3, Informative)

MBGMorden (803437) | more than 4 years ago | (#31766612)

Not really. What we're looking at here is the suitability of something for BEING the measuring stick. You can say that 300 pulsar pulses is a second, or you can say that the time it takes for 2000 cesium atoms to decay is a second if you like (both numbers pulled completely out of thin air, as for the purposes of this discussion actual measurements are irrelevant), and that technically can define a second, but the suitability of that measuring stick is in how consistent those events are. If the cesium atoms are decaying at a far more consistently measurable rate than the pulsar is pulsing, then that is a better measuring stick.

It'd be like saying that a mile is officially defined as how far a certain runner can run in 10 minutes. The fact that it's the official definition doesn't change that it's a poor measurement method, because of the inherent variability involved.

Re:Definition is the Key (1)

vlm (69642) | more than 4 years ago | (#31766760)

The problem is when you cross correlate 100 or 1000 pulsars or atomic clocks to see how well these "measuring sticks" match each other.

Turns out pocket watches are pretty cruddy, pulsars are OK although they assumed they'd be the best (oops), various atomic standards are best although some are better than others.

Look at how NTP works and select clocks.

science journal DUH! (1)

Michael Kristopeit (1751814) | more than 4 years ago | (#31766082)

it doesn't matter if pulsars are more accurate... you'd have to be so far away to observe it, that the photons can get warped by gaseous lenses in between the observation point and the star.

Re:science journal DUH! (4, Funny)

LucidBeast (601749) | more than 4 years ago | (#31766254)

Well, maybe your atom clock is more accurate, but my pulsar timepiece has way brighter display.

Cheap inferior intergalactic imports ... (1)

PolygamousRanchKid (1290638) | more than 4 years ago | (#31766084)

The preprint of their paper, available on the arXiv, shows that terrestrial clocks exceed the accuracy and stability of the astrophysical 'clocks' by all sensible measures, in some cases by several orders of magnitude."

... are obviously not a quality substitute for stuff Made on Earth, despite what Wal-Mart may claim.

Are you sure that the star child workers billions of light years away from our planet are not putting poisonous lead into the atomic clocks made for *your* childeren . . . ?

Buy Made on Earth!

Re:Cheap inferior intergalactic imports ... (1)

robot256 (1635039) | more than 4 years ago | (#31766162)

Buy Made on Earth!

...in China!

Duh. (3, Insightful)

Cyberax (705495) | more than 4 years ago | (#31766100)

Considering that we're using atomic clocks to detect the rate of _spin_ _down_ of several neutron stars (and of course, starquakes and glitches), claiming that neutron stars are somehow superior is just stupid.

Re:Duh. (2, Insightful)

astar (203020) | more than 4 years ago | (#31766298)

there is a strong ideological motivation for the claim that pulsars do it best.

consider that humans can do something new in the universe that the universe can not otherwise do

so this has implications on the nature of the universe and mans relationship to the universe

many of the resulting treatments crap on dominate assumptions that many people think are true

Re:Duh. (1)

MiniMike (234881) | more than 4 years ago | (#31766782)

Well, since the man-made clocks still rely on natural phenomena (just different phenomena than a pulsar) I don't understand why a knowledgeable person would have that motivation. Perhaps I just answered my own question.

Re:Duh. (1)

epiphani (254981) | more than 4 years ago | (#31766944)

The universe can't count in prime numbers. Thinking we can't keep time (a relative concept to begin with) better for than the universe can is somewhat silly.

Re:Duh. (1)

AmazinglySmooth (1668735) | more than 4 years ago | (#31766646)

You can use one pulsar to measure another.

Re:Duh. (1)

Cyberax (705495) | more than 4 years ago | (#31766730)

How?

The speed of spindown is far less than the rate of typical pulsar. You just won't get enough precision to detect spin down and glitches.

Nah, best clock is my girlfriend's clock (0)

Anonymous Coward | more than 4 years ago | (#31766110)

She is always precisely on time, while I am always late.

Re:Nah, best clock is my girlfriend's clock (1)

Explodicle (818405) | more than 4 years ago | (#31766258)

That's better than her being late!

Re:Nah, best clock is my girlfriend's clock (0)

Anonymous Coward | more than 4 years ago | (#31766338)

Better than you being on time (or early) and her being late...

I hope that wasn't too far overhead :P

alien-made clocks ? (0)

Anonymous Coward | more than 4 years ago | (#31766172)

Assuming that man-made clocks are the best in the universe seems a bit arrogant to me. Considering there are billions of galaxies with billions of stars each, some aliens might do better. ^^

Re:alien-made clocks ? (1)

Michael Kristopeit (1751814) | more than 4 years ago | (#31766278)

why would they need to?

Re:alien-made clocks ? (1)

maxwell demon (590494) | more than 4 years ago | (#31766388)

So you deny aliens the status as man? That's biosphereism! :-)

So are you saying.... (0)

halivar (535827) | more than 4 years ago | (#31766186)

Pulsars are terrible wristwatches??? Really?

Bah-DUM-bum *PSSSSHHHHH*

Time Is Irrelevant (0)

Anonymous Coward | more than 4 years ago | (#31766218)

Time is irrelevant, pulsar time, now, doubly so. :-P

Precision is not the same as Accuracy (5, Insightful)

bano (410) | more than 4 years ago | (#31766234)

The summary seems to use precision and accuracy interchangeably, they are in fact quite different.

Re:Precision is not the same as Accuracy (1)

shoobe01 (1785272) | more than 4 years ago | (#31766302)

Thankfully someone caught this before me. Clocks are all about precision. If your clock is inaccurate, set it. If you don't know the difference between precision and accuracy, please stop writing (or editing) blurbs summarizing findings from science journals for the technology section of well-known websites.

Re:Precision is not the same as Accuracy (1)

maxwell demon (590494) | more than 4 years ago | (#31766564)

If your clock is inaccurate, set it.

How do you set a pulsar?
BTW, should I set it to UTC or local time?
SCNR :-)

Re:Precision is not the same as Accuracy (1)

tpstigers (1075021) | more than 4 years ago | (#31766606)

Actually, I'd argue the exact opposite. Accuracy in a clock goes beyond the instant it's first set. If it doesn't run accurately, no amount of precision in the universe will help it. And if it's accurate, it doesn't matter if it's counting centuries, years, days or nanoseconds. For those who want examples: "I was born at 4:15 am EST in the year 1492" is a precise but inaccurate statement. "I was born some time in the sixties" is an accurate but imprecise statement.

Re:Precision is not the same as Accuracy (1)

Lisandro (799651) | more than 4 years ago | (#31766654)

Mod up. I was just about to whine about the same.

Re:Precision is not the same as Accuracy (1)

blair1q (305137) | more than 4 years ago | (#31766732)

Well, no, they said "precision", and then they said "accuracy and stability", two things that combine to imply precision.

And they're talking about precision as a feature of the natural phenomenon being measured, not numerical precision as a mathematical construct used to record the measurements.

Re:Precision is not the same as Accuracy (1)

rm999 (775449) | more than 4 years ago | (#31767128)

I am not an expert on these things, but I'll give an explanation of my best understanding of what they are talking about. Someone please correct me if I am wrong. I am basing a lot of this comment off this page (http://www.febo.com/pages/stability/).

The article is talking about "frequency stability", which is related to both accuracy and precision. When you are talking about keeping time, frequency stability effectively provides a ceiling on both accuracy and the precision you should use. In other words, if your clock is not more stable than some frequency F over some period of time tau, you should not use a precision greater than F, and you should not claim your clock is more accurate than F over the time period tau.

In other words, by claiming the "frequency stability" is better in one clock than another, they are making a statement about both accuracy and the sensible precision to use when referring to the clocks.

Better than all natural clocks, perhaps. (1)

John Hasler (414242) | more than 4 years ago | (#31766262)

But best in the universe? Unlikely.

Re:Better than all natural clocks, perhaps. (1)

geekoid (135745) | more than 4 years ago | (#31766364)

Do you have a better one?

Re:Better than all natural clocks, perhaps. (2, Insightful)

LockeOnLogic (723968) | more than 4 years ago | (#31766538)

Maybe aliens do (i'm half joking)

Re:Better than all natural clocks, perhaps. (1)

Sulphur (1548251) | more than 4 years ago | (#31767006)

Their clocks are wrong.

They are digging in the wrong place.

Re:Better than all natural clocks, perhaps. (1)

maxwell demon (590494) | more than 4 years ago | (#31766608)

There's a better one at Maximegalon.

Overstate much? (1)

Itninja (937614) | more than 4 years ago | (#31766268)

The universe? Really? Maybe the known universe. Or, maybe if we redefine 'universe' to mean Earth. But, I bet there's some sentient algae out there with a better clock.

Re:Overstate much? (1)

geekoid (135745) | more than 4 years ago | (#31766406)

Known universe is implied you pedantic dolt.
If more data comes in, then they can reevaluate the claim. We can not base a claim on what data might happen in the future.

Re:Overstate much? (1)

zygotic mitosis (833691) | more than 4 years ago | (#31766680)

If we take 'universe' here to mean Earth, then I think pulsars are excluded anyway.

Aliens (0)

Anonymous Coward | more than 4 years ago | (#31766308)

Somewhere out there, the aliens reading this are laughing

The universe is 13.75 +/- .17 billion years old.. (3, Funny)

Dalambertian (963810) | more than 4 years ago | (#31766348)

...contrary to numerous claims in astrophysical literature that the natural timing provided by pulsars and white dwarfs is the most precise.

Well now I know why astronomers have such huge error bars - they've been using pulsars to tell time!

How do they know? (3, Interesting)

BitterOak (537666) | more than 4 years ago | (#31766386)

How do you determine which is the best clock in the universe? Don't you need a better one to run a comparison against?

Re:How do they know? (1)

EkriirkE (1075937) | more than 4 years ago | (#31766694)

I don't know about in the universe, but they sure can compare the pulsars to human atomic clocks.

Re:How do they know? (1)

maxwell demon (590494) | more than 4 years ago | (#31766704)

A simple way is to take two of them and see how much they differ. If they were perfect clocks, they'd always show exactly the same time.

Re:How do they know? (1)

mooingyak (720677) | more than 4 years ago | (#31766932)

And when they're not the same, how do you know which one is better?

Re:How do they know? (1)

blair1q (305137) | more than 4 years ago | (#31766816)

If you had just one atomic clock and one pulsar, and you tried to measure the period of one against the period of the other, you wouldn't know which was introducing more noise.

But,

You can run your atomic clocks against each other to determine relative accuracy of atomic clocks.

And you can run pulsars against each other to determine relative accuracy of pulsars.

So then you can run pulsars against atomic clocks to determine relative accuracy between them.

Re:How do they know? (1)

mooingyak (720677) | more than 4 years ago | (#31766962)

So pulsars as a group are not perfect timepieces, but there may still exist a specific pulsar that is superior?

Re:How do they know? (0)

Anonymous Coward | more than 4 years ago | (#31766956)

You take two of the any particular kind of ultimate clock and see how they agree with each other over time.

(Well, more complicated than simple agreement, you compensate for constant drive then measure the entropy of the distribution of the phase noise that you get when you subtract the output of the two clocks).

Oh really? (1)

merikari (205531) | more than 4 years ago | (#31766752)

Let's see which ones are still running after a few million years.

Somewhere on another planet (0)

Anonymous Coward | more than 4 years ago | (#31766798)

"Hey, look, those primitive carbon based lifeforms are being stupidly arrogant again"

Best in the universe? (0)

Anonymous Coward | more than 4 years ago | (#31766984)

I bet the Romulans beg to differ.

How do you figure? (0)

Anonymous Coward | more than 4 years ago | (#31767042)

How do you figure the 'best' clock? You compare two clocks, they differ, which one is wrong? I'm cunfused.

Ridiculous story (0)

Anonymous Coward | more than 4 years ago | (#31767134)

This is a ridiculous story..

  From the first week that pulsars were discovered, back in 196X, it was known that they were slowing down.

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