The first clock precise enough to even measure the irregularity of Earth rotation was only build in 1934.
Before, it was simply the best clock available.
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Before, it was simply the best clock available.
TAI is a separate time scale and it is used to define UTC.
There is now CLOCK_TAI in Linux [1], tai_clock [2] in c++ and of course several high level libraries in many languages (e.g. astropy.time in Python [3])
There are three things you want in a time scale: * Monotonically Increasing * Ticking with a fixed frequency, i.e. an integer multiple of the SI second * Aligned with the solar day
Unfortunately, as always, you can only chose 2 out of the 3.
TAI is 1 + 2, atomic clocks using the caesiun standard ticking at the frequency that is the definition of the SI second forever Increasing.
Then there is UT1, which is 1 + 3 (at least as long as no major disaster happens...). It is purely the orientation of the Earth, measured with radio telescopes.
UTC is 2 + 3, defined with the help of both. It ticks the SI seconds of TAI, but leap seconds are inserted at two possible time slots per year to keep it within 1 second of UT1. The last part is under discussion to be changed to a much longer time, practically eliminating future leap seconds.
The issue then is that POSIX chose the wrong standard for numerical system clocks. And now it is pretty hard to change and it can also be argued that for performance reasons, it shouldn't be changed, as you more often need the civil time than the monotonic time.
The remaining issues are:
* On many systems, it's simple to get TAI * Many software systems do not accept the complexity of this topic and instead just return the wrong answer using simplified assumptions, e.g. of no leap seconds in UTC * There is no standardized way to handle the leap seconds in the Unix time stamp, so on days around the introduction of leap second, the relationship between the Unix timestamp and the actual UTC or TAI time is not clear, several versions exist and that results in uncertainty up to two seconds. * There might be a negative leap second one day, and nothing is ready for it
[1] https://www.man7.org/linux/man-pages/man7/vdso.7.html [2] https://en.cppreference.com/w/cpp/chrono/tai_clock [3] https://docs.astropy.org/en/stable/time/index.html
They only compare to some strange, Russian direct train.
The reference should be the current best connection, which would have one train switch.
The difference between this new connection and the fastest connection with one switch is ~15 minutes.
"Eva's Blumenladen" is the proper name of the shop, what is put on the sign above the door.
"Evas Brille" is just Eva's glasses.
https://en.m.wikipedia.org/wiki/Astrophysical_jet#Rotation_a...
1) it isn't circular, although just barely (it's an ellipse) 2) the length of the day is not really related to the length of a year, and the second was defined as 1 / (24 * 60 * 60) = 1 / 86400 of the mean solar day length
So this is really just a coincidence, there is no mathematical or physical reason why this relationship (the year being close to an even power of 10 times pi seconds) would exist.
"Extraordinary claims require extraordinary evidence."
An older quote, addressing this case more directly would be (Eddington):
"The law that entropy always increases holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations — then so much the worse for Maxwell's equations. If it is found to be contradicted by observation — *well, these experimentalists do bungle things sometimes.* But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation."
That that standard has several thousand pages and internal inconsistencies, ... well
https://en.m.wikipedia.org/wiki/Standardization_of_Office_Op...
Since you mentioned the visualization part, let me comment on my pet pieve:
The rainbow / jet color map should not be used for anything. It distorts your data and is not accessible for people with color vision deficiencies.
If you want to know more, have a look here: https://matplotlib.org/stable/users/explain/colors/colormaps... and this talk here: https://youtu.be/xAoljeRJ3lU
> The frequent use of a double underscores in internal identifiers in Python gave rise to the abbreviation dunder; this was coined by Mark Jackson[3] and independently by Tim Hochberg,[4] within minutes of each other, both in reply to the same question in 2002.[5][6]
In "stable conditions":
* The number of requests in a given time interval will follow a poisson distribution.
* The times of requests will be uniformly distributed
* the duration between two consecutive requests will be exponentially distributed.
The whole sky has 4pi steradian.
The largest instrument to observe cosmic rays is the Pierre Auger Observatory in Argentina, which has detectors placed on an area of over 3000 km².
These are charged particles (protons and fully ionized heavier nuclei), so electromagnetism is a much more efficient way to reach high energies.
All currently proposed mechanisms for cosmic ray acceleration involve turbulent plasmas and shock fronts that reflect particles magnetically, giving them a small bump in energy each time [1] or rotating magnetic fields [2] in sufficiently extreme environments.
[1] https://en.wikipedia.org/wiki/Fermi_acceleration
[2] https://en.wikipedia.org/wiki/Centrifugal_acceleration_(astr...
Gravity just doesn't play a direct role for accelerating charged particles, it's much too weak compared to the electromagnetic force for a charged particle.