On Wed, 02 Jan 2019 08:35:26 -0700, Chris L Peterson
wrote:
On Wed, 02 Jan 2019 09:46:25 +0100, Paul Schlyter
wrote:
On Tue, 01 Jan 2019 07:52:37 -0700, Chris L Peterson
wrote:
On Tue, 01 Jan 2019 09:17:39 +0100, Paul Schlyter
wrote:

On Mon, 31 Dec 2018 09:28:28 -0700, Chris L Peterson
wrote:
But we must be inside the 4D sphere or else we would have no
future.

No, we are on the surface. The surface is "now". The center
is
t=0
(actually, it is (0,0,0,0), the location of the Big Bang).
The
past
is
inside the sphere, where it is not accessible to us.

Which means that in one second we will be almost one lunar
distance
outside this sphere? Since outside the sphere is where the
future
is.

In one second the surface of the sphere will have moved outward
by
one
second, placing everything in the Universe one second later.

As you probably know from relativity time isn't an absolute
quantity.
If we regard time as just a coordinate (with light speed as the
scale
factor to the space coordinates) then this "surface of the sphere"
will fill up the interior as well as the exterior of the sphe
go
anywhere anytime and the "surface of the sphere" will be there!

Every point in spacetime is defined by a single coordinate,
(x,y,z,t).
Relativity doesn't change that. There is only one surface; the
interior (that is, space in the past) isn't a surface.

There must be one surface for every t. Unless one claims that every t
except the present "does not exist".