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Physicists Find That As Clocks Get More Precise, Time Gets More Fuzzy (sciencealert.com)
Physicists "have combined two grand theories of physics to conclude not only is time not universally consistent, any clock we use to measure it will blur the flow of time in its surrounding space." An anonymous reader quotes ScienceAlert:
A team of physicists from the University of Vienna and the Austrian Academy of Sciences have applied quantum mechanics and general relativity to argue that increasing the precision of measurements on clocks in the same space also increases their warping of time... [W]hile the theories are both supported by experiments, they usually don't play well together, forcing physicists to consider a new theory that will allow them both to be correct at the same time...
In this case, the physicists hypothesized the act of measuring time in greater detail requires the possibility of increasing amounts of energy, in turn making measurements in the immediate neighborhood of any time-keeping devices less precise. "Our findings suggest that we need to re-examine our ideas about the nature of time when both quantum mechanics and general relativity are taken into account," says researcher Esteban Castro.
The article opens with the statement that "time is weird," noting that despite our own human-centric expectations, "the Universe doesn't have a master clock to run by."
In this case, the physicists hypothesized the act of measuring time in greater detail requires the possibility of increasing amounts of energy, in turn making measurements in the immediate neighborhood of any time-keeping devices less precise. "Our findings suggest that we need to re-examine our ideas about the nature of time when both quantum mechanics and general relativity are taken into account," says researcher Esteban Castro.
The article opens with the statement that "time is weird," noting that despite our own human-centric expectations, "the Universe doesn't have a master clock to run by."
All the uncertainty relationships in QM come from fourier conjugate variables. So for example, if you measure a low frequency for a short time you will be uncertain about the exact frequency. If you restrict a wave to a narrow slit then it take more direction forier terms to represent the truncated plane wave.
time and frequency are fourier conjugates. and plank's constant, which is constant, has the units that convert frequency to energy. This is why we say that time and energy are conjugates.
Some drink at the fountain of knowledge. Others just gargle.
Or it's Heisenberg up to his usual antics. Time and energy appear as conjugate variables in the quantum wave function solution to the Schroedinger equation for an oscillator (like a ticking clock), so the precision of your clock (delta-t) is inversely proportional to the precision of your energy measurement (delta-E), in the same way that the precision of position and momentum measurements are limited by the uncertainty principle.
Energy curves its surrounding space under General Relativity. This would imply energy of whatever system does the ticking in your clock is constantly being "measured" by, at a minimum, the fabric of space-time, independent of how well you isolate it from the rest of the clock. So that puts a limit on the uncertainty in the energy measurement of whatever does the ticking. If delta-E is limited to be below a certain size, then delta-t is forced to be above some size, so you necessarily get some small variation in the time between ticks of the clock.
This results in a tradeoff between precision and accuracy. Precision requires many small ticks, so delta-t makes up a larger fraction of the duration of each clock's tick. A clock which ticks less often becomes more accurate (delta-t is a smaller fraction of the total time between ticks), but fewer ticks limits the precision of your measurement.
At least, as a physics grad student, that's how I've interpreted the result that TFA is utterly failing to convey properly.
That WMAP picture of the CMB is AFTER a sort of ying-yang red and blue shift pattern which is the result of our motion through space (the combination of our motion around the galaxy, our motion around our sun and our galaxy around the general mass of the universe) has been removed. And we're not moving relativistically.
It's just a very small difference.
Yet that is how even the CMB is, that you have to remove this effect of our proper motion to get a scale that will show up the detail difference in the CMB that caused the clustering of matter in galaxies we see today.
We already see that change in the CMB.
Then remove it so the remaining differences are inherent in the CMB and not our unsteady position in space.