[Avodah] R' Nissim Karelitz's Beis Din: Kohanim cannot fly from Ben Gurion

[Zev Sero via Avodah]

On 31/10/16 13:32, via Avodah wrote:
 > Zev Sero wrote:
 >> R Eli Turkel wrote:

>>> In addition to questions about the moon how about accounting for the
>>> curvature of the earth? [--RET]

>> What about it?  How is it relevant?   at any given point in the
>> universe, you are either above a grave or you are not.

> At any given point in the universe, what do the words "above" and
> "below" even /mean/?

No matter where in the universe you are, you are above every point on a 
line that extends between you and the centre, and below every point on 
that line's infinite extension.  At least until we reach the point where 
relativistic curvature of space-time becomes significant.



> The curvature of the earth may not be relevant but the earth's rotation
> around its axis surely is.

No, it isn't.  All it means is that objects not in a geosynchronous 
orbit are constantly moving over the earth, passing over different 
points at different times, exactly as if they were in a plane or a car, 
or even walking.



> But how far out in space is this true?

Forever.  Why is this surprising?  What basis do you have for supposing 
otherwise?


>  If you were standing in a
> graveyard and you looked up and saw, say, Orion's belt, would that mean
> that a kohen could not travel to one of Orion's stars because the tumah
> from the cemetery extends all the way UP to those stars?  But no, in the
> course of the night, Orion moves!  (Well, our planet moves.)

When it is not above the grave there is no problem.  When it is there 
is.  If a kohen knows that every 24 hours it passes above a grave, then 
of course he may not go there.  I fail to see why anyone could have a 
problem with this.


> So now where is "up"?  Where is "above"?

Where it's always been.  How is this harder to understand than a person 
who "flies" in a bus at an altitude of about one metre?



> I could also pose the problem a different way.  Let's say you're on a
> ride in an amusement park, some kind of Tilt-a-Whirl, and the ride is
> such that it twirls you around.  [...].

As you say, you are *moving*.  Thus what is above you changes 
constantly, just like anyone else who is moving.


> It seems to me that the atmosphere, like that transparent canopy, must
> be the limit of "above" a grave.  (How high? I don't know.) Otherwise
> all of outer space in every direction is "above" us as we spin!

No, only one direction is above you.  We just finished sukkos, when we 
demonstrated the concept of six directions.  Have we already forgotten? :-)


-- 
Zev Sero                Hit the road, Jack
zev at sero.name           but please come back once more