[LEAPSECS] presentations from AAS Future of Time sessions

[Magnus Danielson]

On 14/01/14 17:28, Poul-Henning Kamp wrote:

> In message <0CCAFA25-523E-4022-A993-4BC2D9FE56A3 at noao.edu>, Rob Seaman writes:

>

>> A timescale that omits that connection should not be denoted

>> Universal Time of any kind, coordinated or not.

>

> I would argue that any timescale called "universal something" should

> not be tied to any particular lump of orbital debris.

>

> In particular not in deference to lack of imagination on the part

> of scientist two centuries ago.


Universal means all of the world, world meaning our world, so it is that 
lump of orbital debris. It's just that the word has undergone a shift in 
meaning.

Universal Pictures never meant to say that they where making movies for 
other solar systems. Look at the earth they are using as symbol:
http://www.universalpictures.com/

If you where right about not basing it on the orbital debris, then we 
should not attempt to be using concepts like seconds, minutes, hours, 
days, weeks, months, years which all covers the concept derived from the 
basic properties. I'm not even sure caesium would be the natural 
selection of reference, and if you use caesium, you are expected to be 
using it at the gravitational pull matching up with mean sea-level of 
that orbital debris you where talking about.

Let's face it, this lump of orbital debris we call our home planet is 
what we have as a reference and try to have common set of references. 
This is our "universe".

Cheers,
Magnus