[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: starship-design: Genuine STR question

Kyle R. Mcallister writes:
 > Relativity, despite what some say, is not easy to understand or learn.
 > You will do what I did at first: look at it and say: huh? You'll also
 > have a tendancy to say that the observers on earth are somehow more
 > privileged than those on the ship, but it is not so. It doesn't really
 > make sense at first.

The biggest stumbling blocks for beginners seem to be:

Spacetime (as opposed to Newtonian space) is not Euclidean,
although for everyday life Euclidean geometry is a near-perfect

Simultaneity is a completely relative concept.  There is only one 
reference frame in which two events can be simultaneous.  This
turns out to be the resolution to a great many relativistic

Other than that, special relativity isn't hard to learn, in that
the math isn't hard and a lot of other Newtonian concepts like
conservation of momentum or conservation of mass remain true.  I
see the difficulty as not in the structure of special relativity
theory, but in overcoming some pervasive assumptions.

 > To me, it still seems inadequate, so I am waiting
 > for a theory of quantum gravity to be found. Or something like it. But
 > stick with it, ask people questions if you don't understand something.
 > No question, if honest, is ever stupid.

General relativity seems to hold some promise for FTL loopholes,
but even the ones that have been well-postulated are awfully
difficult to exploit (i.e. building an infinitely long ultradense 
rotating cylinder or creating a region of negative energy density 
are not exactly seen to be feasible).  There's no way to tell
whether a theory of quantum gravity will close or widen those
potential loopholes.