previous post wondered about what atomic clocks everywhere might be useful for, in particular crypto. the following article has more information on how mapping gravity via time differences via highest-precision timekeeping relates to unlocking mysteries of the earth's interior... (thus geological, geophysical) [0] one aspect that has me puzzled about timing is the claim by Apple that the Apple Watch is "One of the most accurate watches ever" while also noting its accuracy is 50 microseconds, and likely has its timing signal indirectly routed through the iPhone thus delayed prior to setting the internal clock. interesting article on this issue [1], with a backgrounder on existing timing technologies available today. in particular, information about Apple's time servers that are linked to UTC at nanosecond accuracy, and also that the clocks or timing circuits inside smartphones and tablets are _not as accurate as i imagined, also losing seconds a day (in this way somewhat like a mechanical watch for precision). the thing about the Apple Watch claim of timing accuracy, which the article makes clear, is that a GPS watch that gets its signal from orbiting satellites (via whatever speed-of-light & atmospheric signaling delay) is receiving a time signal that is accurate in the realm of nanoseconds from the universal standard, via several synchronized atomic clocks onboard the GPS satellites. so apparently that accurate timing signal has to transverse space and time to get to another distant location, and it is unknown if at its destination it has this accuracy or only when the signal is sent. the latter may be possible with additional calculations based on various parameters of GPS, thus the stated 50ns accuracy could be presumed that of a GPS watch if not iPhone GPS time signal. and yet with the tethering of the Apple Watch to the iPhone to maintain its timekeeping, somehow this 50 nanosecond accuracy drops to 50 microseconds, which the observer noted is "a million times worse than...the accuracy delivered by GPS." [1] because of this it is puzzling how the claim of ~extreme accuracy can be made by Apple when an iPhone has presumably better timing resolution due to design decisions, than a device categorized as a watch as if in the same lineage as precision chronometers that defined engineering excellence and feats of microengineering, which also /appear/ as watchfaces on the system-on-a-chip device, and yet that same adherence to accuracy is seemingly not occurring even while still being claimed. to give a sense of the issue, via proportion, a short video of Grace Hopper provides a way of considering this situation by measuring the maximum distance electricity travels in space in a nanosecond and microsecond. [2] this then allows hypothetical comparison between a GPS timing signal sent directly to a smartwatch (50ns*11.8inches = 49.1667 feet) to that GSP or other time signal relayed to the Apple Watch via tethered iPhone and its circuitry (50ms*984feet = 49,200 feet). in other words, length corresponds with accuracy to a universal time standard and a GPS watch is potentially '49 feet accurate' while the tethered Apple Watch seems to be '49,200 feet accurate' and saying this is precise in a horological context of timekeeping and precision timepieces. it just seemed so backwards to me because if there was onboard GPS on the Apple Watch then it would have precision that other devices also have, and the claim of precision would be self-evident, instead of potentially being marketing-speak to sell computer-devices via the pretext of its being a watch, etc. so a boundary or threshold appears to have been crossed or priorities may be different than expected in this way. an onboard radio antenna would also provide higher resolution, though perhaps the timing chip inside the SoC watch is not built around highest precision as may otherwise be assumed. hopefully in the future it will be. the issue that seems relevant in the lag or delay is that there is that much more room for things to happen in terms of unaccounted for delays outside the parameters of hours:minutes:seconds, if milliseconds is some threshold, and then events are occurring in a realm of microseconds or even potentially nanoseconds, and how crypto could be operating or calculating in those dimensions and dynamics otherwise unseen or unobservable, such as 2+2=4 if looked at one way, and 2+2=5 if viewed outside those boundaries. [3] note: i specifically wrote about the above issue as part of a larger Apple Watch analysis, [4] and these recent articles provided more to consider about what may be involved. [4] -- 0. Cryogenic clocks pave the way to new measurements http://phys.org/news/2015-02-centimeter-cryogenic-clocks-pave.html [quote] According to Katori, "It was a great feeling to have shown this excellent agreement between the clocks. If we can miniaturize this technology further, it would have useful applications, since tiny fluctuations in gravitational potential could be used to detect underground resources, underground spaces, and the movement of lava. We also hope that in the future, this will accelerate the movement toward a new definition of the international second, based on optical lattice clocks, to an even more stringent standard than the current definition of the second, which is based on cesium oscillation." [/unquote] 1. How Apple Watch achieves its timekeeping accuracy http://watch.camp/2014/11/apple-watch-timekeeping-accuracy/ 2. Grace Hopper - Nanoseconds / Microseconds https://www.youtube.com/watch?v=JEpsKnWZrJ8 3. [2].5 + [2].5 = [5] 4. AWO: critique of Apple Watch concept… https://appleobservations.wordpress.com/index/5-2/