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Man-Made Atomic Clocks the Best In the Universe
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."
Man > Nature... Take that religion!
God is off playing with fusion that produces excess energy.
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.
.
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.
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.
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.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
Isn't the best clock going to be one in your frame of reference?
Give me Classic Slashdot or give me death!
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".
Whatever the measuring stick is for "minute" and "second", that's the most accurate clock, by definition.
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.
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!
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
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.
She is always precisely on time, while I am always late.
Please excuse the poor english.
A man walks up to God and says: ...would you give me a cent?
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...
God says:
- Just a second, please.
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. ^^
He laughs at all those who think the pulsars are there to measure time.
The Tao of math: The numbers you can count are not the real numbers.
Pulsars are terrible wristwatches??? Really?
Bah-DUM-bum *PSSSSHHHHH*
Time is irrelevant, pulsar time, now, doubly so. :-P
The summary seems to use precision and accuracy interchangeably, they are in fact quite different.
But best in the universe? Unlikely.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
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.
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
Somewhere out there, the aliens reading this are laughing
Well now I know why astronomers have such huge error bars - they've been using pulsars to tell time!
How do you determine which is the best clock in the universe? Don't you need a better one to run a comparison against?
If I can be modded down for being a troll, can I be modded up for being an orc, or a balrog?
He's right behind you.
I'm within your potentiality
Let's see which ones are still running after a few million years.
My other SIG is a Sauer.
"Hey, look, those primitive carbon based lifeforms are being stupidly arrogant again"
I bet the Romulans beg to differ.
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.
How do you figure the 'best' clock? You compare two clocks, they differ, which one is wrong? I'm cunfused.
Yet, nature created man and used him as a tool to create a very precise clock. There's no competition here, really.
This is a ridiculous story..
From the first week that pulsars were discovered, back in 196X, it was known that they were slowing down.
The irregularity of pulsars has been known for decades now. Most of them are better than your watch, but I've got a textbook on pulsars that's twenty years old and mentions the drifts in their frequency in the first few pages.
Proud member of the Weirdo-American community.
Wouldn't this only work if you used a classical space-time model, or at least normalized to our local frame of reference? If we account for relativistic effects, wouldn't an external observer probably not see the same degree of accuracy from our clocks as we perceive? And the "most accurate" claim doesn't address other possible phenomena, such as isotopic decay in natural circumstances.
Man-made atomic clocks, as opposed to the atomic clocks made by aliens.
Most of them are better than your watch, but I've got a textbook on pulsars that's twenty years old and mentions the drifts in their frequency in the first few pages.
Uh yes it's been known that pulsars do in fact have period drift for many years. However for quite some time after their discovery, their drift was vastly smaller than any man-made clock. This is what lead to the common belief that pulsars are the best (known) clocks in the universe, because for at least several decades they were. Man-made clocks have made tremendous improvements however, and now are better than pulsars. Those super-awesome clocks still experience frequency instability, though. It's just on the order of 1 in 10^17 instead of 10^15 like the best pulsars.
Which based on the statement that our clocks have improved "more than an order of magnitude, on average, in each decade", while we have not found pulsars significantly better than those previously known, means that it's possible that when your textbook was written man-made clocks were only just surpassing pulsars or possibly even still behind.
So yeah this probably is not NEW news, but it's probably going to be news to a lot of people who had the (previously correct) idea that pulsars were better than the best man-made clocks. And no you shouldn't have assumed man-made clocks were better based simply on the existence of frequency instability in pulsars.
The enemies of Democracy are
I don't understand, how do they define time so that one measure is 'better' than another? Just consistency or what? In other words, how do they know which one is more 'accurate'? (what does 'accurate' mean?)
mod parent up funny - that one is going straight into the Vault!
Wait! Whats a sig?
Isn't the question really which object is the best oscillator, atoms, ions or pulsars?
The only man-made components are the manipulation, measurement and observation.
I suppose that the article may be correct from a purely technical perspective. But, it doesn't take into account the reasons behind which scientists are looking to pulsars and white dwarfs for a gold standard. Atomic clocks will only maintain time while we are technologically advanced. ie, they do not maintain time during or after any of singularity events that may happen. So if there is an event disruptive to civilisation, the clocks stop, but the pulsars,etc, will still be there. Thus any subsequent intelligent, technological society would be able to maintain a continuous time reference if they so desired and any of the original reference material was available.
It's all Chaos. Nothing is perfect. All the rules and predictions can't prevent something eventually going wrong. That clock comes close simply because we've controlled it to the extreme.
Truth is a matter of perspective. Wear the other guy's shoes before you dismiss him.
Gravity affects light (electro-magnetic radiation in discrete quanta called photons) in the exact same way it affects mass: F = G * m1 * m2 / r^2 where m1 and m2 are the masses of the respective bodies. G is the universal gravitation constant. r is the distance between the bodies. A photon of light has mass: m = E/c2 (where c is the velocity of light in a vacuum) and E is the energy of the photon (which is determined by the frequency). CAVEAT: The above uses the classical Newtonian formula for gravity. At the velocity of light, it isn't 100% correct. To have the exact correct value one must use the general theory of relativity (which the newtonian formula is an approximation of at normal velocities and energy levels). Regardlesss, the point is that mass and light are affecte the same by gravity.
Over-the-top Response Guy! Giving "Over-the-Top Responses" since 1970.
I don't understand the point of this article. It's already known that pulsars shift in timing as they radiate energy into space and cool. This cooling process causes two effects, a slowing down of the pulsar's rotation rate and rearrangement of the interior of the pulsar (apparently there are plenty of phase changes in the internal structure of the pulsar, which has the side effect of changing the moment of inertia for the pulsar. Either effect is as I understand it, larger than the error in cesium clocks.
The manmade clock might be more accurate in the short term, but the pulsar will keep on ticking perhaps millions of times longer or more.
Man discovered both of these methods for measuring time - he didn't create the properties being measured.
You can measure distance with a stick and you can also measure it more precisely by observing how far light travels within a given time. Who's the loser now?
So where can we get the list of all the atomic clocks in the universe? I'm sure that lots of researchers here on Earth would like to read it.
I am a bit surprised to read that none of the other technological civilizations out there have ever built a clock better than ours. Does this mean that we've reached the best possible clock, and we'll never build a better one?
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
I thought being stuck in Earths gravity field means our time is off compered to the rest of the universe.
I mean, run a hundred atomic clocks (and compare their results) vs a hundred pulsars?
I'd think it could only mean all atomic clocks are a subject to the same interference in equal degree, while pulsars are subject to different interferences, being so spatially scattered et al.
I mean, if -all- atomic clocks are off by almost exactly 0.01s in a hour, what is there to tell us they are? They will all still show the same number.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
It is really a big achievement for mankind on Earth. Hats off to all the humans!! http://www.articlesbase.com/health-articles/force-factor-review-amp-free-trial-2113761.html
I don't think quasars were designed with accurate temporal measurement in mind. Rather a pointless comparison, really.
What a depressingly stupid machine.
My guess is that pulsar timing is similar in concept to what happened when John Harrison when he tried making an accurate clock for determining longitude.
http://en.wikipedia.org/wiki/John_Harrison
His early clocks just kept getting larger and more complex, but they were never able to achieve the needed accuracy on a moving, rocking ship for weeks on end.
His solution? He made an very SMALL clock, what amounts to a pocket watch, and was able to achieve accuracy in a variable environment.
Atoms are always going to be more consistent than a celestial object, because electrons can be less susceptible to external forces like aerodynamic drag, object imperfections and inconsistencies, impact bombardment, proximity of other similar objects, and the myriad other things that can affect rotation of an object larger than, say, a cat.
Sure, our "man-made" clocks are more accurate, but that is only because nature has better oscillators that we are capable of observing.
Now that we have the best clocks in the universe, it's time to sell them to the aliens!