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Re:A clock that can detect tiny shifts in the flow of time i... by nullc on Monday November 03, 2014 @08:11PM (#8554666)
I'm glad you enjoyed it, but in my opinion the article was misleading. Not just simplified.

I didn't go on and on in detail about systemic and random effects, linking to NIST tech reports on all the corrections they have to do on primary standards (http://tf.boulder.nist.gov/general/pdf/1846.pdf?origin=publi... on the redshift error at NISTs boulder facilities; and http://tf.boulder.nist.gov/general/pdf/2704.pdf on the sources of error in the F2 primary reference, see section 3.2 on relativistic effects), or pointing out people's amateur time keeping experiments where they demonstrate relativistic influence on decades old hardware ( http://leapsecond.com/ptti2006/tvb-project-great-ptti-ppt.pd... (this presentation is long and a ton of fun)), etc. or all the other bits of trash I could have pulled out to demonstrate knowing something here... because that wasn't my goal, the only point I was trying to make is that the article was likely to make many readers _less_ knowledgeable about the subject.

(But I will give those links now, because this argument is boring and time is neat!)

Perhaps you have enough background that you were not thrown off by the seeming claim that improved accuracy somehow makes these experimental references _less useful_, and you already know that relativistic effects aren't unique to optical lattice clocks and already must be compensated for, but I am sure that this is not universally the case.

What I get from the article isn't nothing... Potentially I get community around me which is less informed than they started and all that entails. Perhaps that's compensated for the fun they had reading about an interesting subject? or the additional learning they do after? I don't know, but I think the article could have been just as enjoyable without the bogus mystique that makes it misleading.

But if pointing out an article was, in my opinion, potentially misleading makes me everything that is wrong about Hacker News, I'll wear that proudly.

I, for one, think it's more likely the case that crappy shock headlines like "end time as we know it", constructed drama, and false freshness are a bigger drag on HN (and wider society) than any of my posts are likely to be... but to each his own.

Re:A clock that can detect tiny shifts in the flow of time i... by foobarian on Monday November 03, 2014 @08:34PM (#8554726)
For what it's worth, the new thing I got from the article is the unexpected idea that one could usefully measure non-time phenomena with a really precise clock, such as gravity or altitude. Definitely more thought inspiring than many other articles, in spite of the way it was written.
Re:A clock that can detect tiny shifts in the flow of time i... by wglb on Monday November 03, 2014 @09:19PM (#8554851)
You didn't really respond to his No one cares about your intellectual superiority, or the fact this might be a special interest for you part of his comment.

Your tone and delivery is a bit offputting.

And the thing that I didn't see you comment on that I found particularly fascinating was that the increased resolution of these clocks is such that you can discern differences in relativistic effect between floor and wall. That changes how I think of time.

(My favorite headline that I read sometime around 1965 is "Dating Events in the Vicinity of a Leap Second.)

Re:A clock that can detect tiny shifts in the flow of time i... by nullc on Monday November 03, 2014 @11:10PM (#8555106)
OK. Dunno what to say there. I thought the article was misleading because it was intentionally sensationalized, not due to some lack of intellectual capability or because it wasn't addressed at an audience with a background in the subject. I'm sure that I know less about the subject than everyone interviewed in in the article. If anything, I think knowledge makes it better, since you're not likely to be mislead by it.

Wrt relativistic effect, the first NIST paper I cited shows that they needed altitude uncertainty less than 1m to avoid redshift from dominating the clock's error. The second shows that for the improved F2 reference redshift is one of the largest sources of uncertainty (and the corrected part is orders of magnitude larger than the other listed systemic errors). It's really cool, I agree. I'm happy to have people share in enjoying that, but sad about whatever causes the press to always have to present things as new and categorically different than what came before.

There are a number of really cool things they didn't mention: For example, these optical lattice clocks that they're talking about are solid state-- involving mostly only lasers and vacuum cells. Unlike cesium based atomic clocks, they may have reasonable prospects of being mass produced inexpensively in the future, and efforts to do this are being funded by DARPA (useful for many military applications, like jamming systems and anti-jamming, navigation, and various sensing applications). So unlike the state of the art atomic references these things may someday show up in very inexpensive equipment, and allow for some fun science experiments, improvements to reliable distributed systems, long baseline amateur radio astronomy, etc.

Or, Tom Van Baak measuring gravitational redshift with a minivan and some old HP cesium beam clocks. okay, not "floor to wall", but if you haven't read his presentation on it, you should, it's a load of fun and IMO, more accessible in that it's not talking about technology that exists in a rats nest of cables on an optical table in a single lab, but just old junk you can find surplus. :)