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Single-Ion Clock 100 Times More Accurate Than Atomic Clock
New submitter labnet writes with this excerpt from news.com.au: "University of New South Wales School of Physics professor Victor Flambaum has found a method of timekeeping nearly 100 times more accurate than the best atomic clocks. By using the orbit of a neutron around an atomic nucleus he says the system stays accurate to within 1/20th of a second over billions of years. Although perhaps not for daily use, the technology could prove valuable in science experiments where chronological accuracy is paramount, Prof Flambaum said."
until it comes with indiglo i don't want it
Eventually you'll be so accurate that walking by the thing will cause enough relativistic distortions that you can no longer claim to have any accuracy at all.
You kidding me? The prospect of GPS-guided bullets accurate to the millimeter will have the US military pursuing this in next-gen GPS satellites as soon as the technology is viable. Hell, this'll be the most valuable update to military hardware in decades.
Viable Slashdot alternatives: https://pipedot.org/ and http://soylentnews.org/
Could, could, could, could. Just a method of timekeeping that *could* be used, but has many issues. How about an post on warp drives next?
...what is the point of this?
Genuinely. I'm seriously interested. I want to know the kind of science which requires timings of this accuracy. I think they must be some really exciting experiments to be studying phenomena on that short a timescale.
Wouldn't "reading" the time change the orbit of the neutron?
Comment removed based on user account deletion
http://arxiv.org/abs/1110.2490
And here I was, thinking that neutrons were inside the nucleus and electrons were orbiting around it. What's going on here? How can a neutron orbit a nucleus? It's an actual question, I know the atomic models I was once taught are way out of date (by a couple of centuries, probably), but I never heard of neutrons orbiting nuclei.
It was my understanding that since the rejection of the Bohr model of the atom that we didn't think electrons "orbited" an atomic nucleus, that they were "smeared out" throughout their energy levels. What am I missing?
why cant i buy a wristwatch with this technology built in it?
Politics is Treachery, Religion is Brainwashing
It'd be nice if some physics professor *cough* could solve those problems before making some shit that can be accurate for a billion years! See what I did there? That was just passive aggressive right there, wasn't it? Too much Portal, lately...
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
I can't even get my atomic watch to set properly from the time signal that exists now.
I must be too far from Denver for the signal to get to my watch. Which sucks, since it defeats the whole purpose of having that.
Lost at C:>. Found at C.
If an atomic clock is your most accurate timepiece then how on earth can you tell if something is more accurate?
Can someone explain?
Also , given that a second is defined in terms of the ceasium atom as used in atomic clocks then surely anything that deviates from this is by definition LESS accurate (if you see what I mean)?
It's about time
...what is the point of this?
Genuinely. I'm seriously interested. I want to know the kind of science which requires timings of this accuracy. I think they must be some really exciting experiments to be studying phenomena on that short a timescale.
Maybe those guys who thought they measured something traveling faster than the speed of light could use a more accurate clock (not to mention a better plug) ;-)
Yes, because being off by 2 seconds every billion years is something to worry about. I am sick of having to adjust my watch for the inaccuracy of atomic clocks.
Isn't that really what /. people care about? Alien ship crashes from another galaxy. "Is the ship powered by Linux?"
A preprint is available on arXiv at http://arxiv.org/abs/1110.2490
A nuclear transition in triply-ionized 229Th has been found which is particularly insensitive to external magnetic fields and electron configuration, which gives the potential for a very stable clock,several orders of magnitude better than current clocks if phase comparisons can be made across a scale of days or weeks. The transition energy is at 163nm (in the ultraviolet). To take advantage of this clock an extremely stable laser at this wavelength (using current best clocks) will need to be created.
A whole lot of science and engineering needs this. We have communication networks that give us ability to distriute experiments and measurements, but a lot of those aren't very useful without a very precise time reference; the networks, as they are, are quite poor at distributing time. Examples: suppose you want to measure time-of-flight of particles across the globe (neutrinos or otherwise); large base telescope (whether radio or optical); more accurate global positioning. The prerequisite in all cases is an ultra-accurate timebase. In fact, large base optical telescopes will require very stable and accurate distributed local oscillators (heterodynes), lack of one is one of the reasons why we don't have optical-to-RF heterodynes for imaging; RF-to-RF heterodynes, even distributed ones, are nothing new and are used for radioastronomy all the time -- optical ones are hard because you need orders of magnitude better clock source in terms of phase noise and drift.
A successful API design takes a mixture of software design and pedagogy.
I've always wondered, with regard to the accuracy of clocks like this, how can you actually tell how accurate it is?
William of Ockham had no beard. The most likely explanation is that it was chewed off by squirrels every morning.
It's an exciting idea, and it's streaks ahead of 'traditional' microwave transition atomic clocks. These do not represent the state of the art, however, for which one should look at the experimentally demonstrated ~9e-18 accuracy by the Wineland group at NIST http://arxiv.org/abs/0911.4527v2 ; http://www.nist.gov/physlab/div847/grp10/ , or the Strontium ion clocks at NPL (Teddington, UK) Essentially, the higher the frequency, the more clicks you get in a certain time, and the more accurate your clock can be (the smaller an error one missed click would represent). The caesium atomic clock is about 10 GHz (1E10 Hz). Strontium is in the optical, so a few 100THz (1E14). Aluminium ions are at about 1PHz (1E15 Hz). This new proposal with Thorium is around 7.6eV, which is about 2PHz, so not a million miles away from the current, demonstrated, state of the art. Also... orbit of the neutron around the nucleus isn't a fair description of a magnetic dipole transition, which would more accurately be describes as a flip in the direction of the neutron's spin axis. :)
Can't find one even myself! Sounds like it's no fun anymore :-|
Slashdot, fix the reply notifications... You won't get away with it...
VERY cool for GPS if they ever upgrade the satellites... also, "Professor Victor Flaumbaum" is a badass name.
at which point will use it for a RND seed generator
every day http://en.wikipedia.org/wiki/Special:Random
my wife will still insist that she's 39.
If Server A has 90% uptime and Server B has 99% uptime, that does not mean that Server B is up 10x more than Server A, even though Server A is down 10x more than Server B. In fact, Server B is only 10% better than Server A. Or, 1/10 as bad.*
So, while the old clock may drift 100x more than this new one in a certain amount of time, or this new one might last 100x longer before drifting a certain amount (or whatever--the .au article is total puff and I don't care enough to look at the source), it is almost certainly not 100x more accurate. At best, it's 1/100th as inaccurate.
* The difference between 36 days of downtime per year versus 4 days might be the difference between "useful" and "completely worthless", making Server B 100x better, but that's not what we're measuring here.
Dear Slashdot: next time you want to mess with the site, add a rich-text editor for comments.
It all seems like an unnecessary gain.
Kind of like choosing a car that can reach 210mph over one that can only do 150mph when the national speed limit is only 70mph.
Yes, I know the figures don't show 100x but it just seems that it's pointlessly better than the currrent best clock which is already better than most people would ever need.
Maybe YOU don't need it, but some of us have real jobs and need to know where to be, down to the femtosecond.
I would have had to wind my old clock in a few hundred million years, but after I get one of these babies, I won't have to.
--
So, honest question, how do you measure the accuracy of the world's most accurate clock? I mean, what do you measure it against?
Come on guys, more opportunities for Faster Than Light travel. May be not yet for mortals but for the particles shot through a tunnel in alps, all it takes is a few bad connections and some inaccurate clocks, and superluminal speed becomes a reality.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Yes, there will be relativistic drift, but the clocks won't be accurate enough to detect it. Lets say the relativistic drift is actually pretty enormous, 1 second per year, and your two average desk clocks drift by up to 1 second per day, or six minutes per year. The random noise will tend to cancel itself out, so after a year the desk clocks will likely still be within a minute or so of "true", but they could be as much as twelve minutes apart if one ran consistently fast and the other consistently slow, and there's no telling which will be which.
So how exactly are you supposed to use them to measure the 1 second difference due to time dilation? You can't, the signal is lost in the noise. You could perhaps put a few thousand clocks in each location and do statistical analysis do discover there was 0.7+/-0.5 seconds of relativistic drift over the course of the year, but that's a different beast entirely. And in the postulated scenario of stacked atomic clocks you're probably talking less than a picosecond of drift per year, you can't fit enough desk cocks in the building for statistics to tease the signal out of that noise.
...what is the point of this?
Genuinely. I'm seriously interested. I want to know the kind of science which requires timings of this accuracy. I think they must be some really exciting experiments to be studying phenomena on that short a timescale.
High frequency gravitational waves? I recall reading about this a while ago - i imagine that it requires an exceedingly accurate time reference, since the effect of grav waves is so small.
omnipotent being
So fix it yourself.
Make the clock more accurate, change the laws of physics to allow for more precise clocks, or simply distort time to your will.
It's what I do.
Yeah, but do you want to be the guy who has to sit there counting that neutron going past?
A guy could ruin his eyes with that sort of fine work.
No, at least according to Special and general relativity, there is no preferred direction to the universe, and there is no such thing as "absolute still". There's no way to not move in a universe where the space itself is moving as well.
Movement must always be defined in relative terms, since general relativity is background independent.
Similarly, when dealing with particles, there's no "absolute still" since that is the same as absolute zero, which is an asymptotic physical limit to the temperature.
Hectice, baby, Mercator says hello to you
High frequency gravitational waves? I recall reading about this a while ago - i imagine that it requires an exceedingly accurate time reference, since the effect of grav waves is so small.
No gravitational wave of any frequency has ever been observed.
No gravitational wave of any frequency has ever been observed.
Indeed - what i mentioned is an experiment to verify their existence. I've looked it up.
In the words of david Mermin: "Shut up and calculate!"
is Foxconn shipping them yet?
Oh, I'm sorry sir, I thought you were referring to me, Mr. Wensleydale.
I want to know the kind of science which requires timings of this accuracy
The recent CERN / Gran Sasso experiments on neutrino velocity, for instance. Better timing translates into better certainty and better reproducibility.
But will this help me have a better countdown script on my website?
I can't believe /. has actually linked to a news.com.au "article". That site makes UK's The Sun look like a peer reviewed scientific journal...
How about some actual details on the new clock, which certainly won't be found on the Aussie tabloids.
Ever since the storms in the mid-west, the atomic clock from Bolder Colorado has stopped transmitting its signal. My three radio receiver (atomic) wall clocks use these signals to keep precision to 1/10th second a day. Now my clocks are out of tolerance and one is running fast, while the others are running slow.
In jest, if all were running slow, I would probably miss the bus to take me to the office.
Leslie Satenstein Montreal Quebec Canada