Re: Can matter(stuff that has rest mass) travel at the speed of light?

Alan,

Thanks for the question.  It is true that a material object can not travel at 
the speed of light.  Only "things" which are massless can travel at the speed of 
light, and in fact they MUST travel at the speed of light.

What we humans perceive as an object is a composite entity composed of more 
elementary components, atoms, which have a "particular" arrangement.  Since the 
atoms only come in a limited variety of types, it is the arrangement which 
really defines the composite object, and so information about the arrangement 
could be used to reconstruct the object.

In your scenario the only "thing" which travels at light speed is light itself. 
This light can carry a DESCRIPTION of the object at the transmission end.  While 
the description is useful, it is in my view quite distinct from the object 
itself; it is an abstraction which lacks the functionality of the object while 
possessing the property of being encodable into various media, including 
modulated light.  The matter that makes up the object does not travel at light 
speed.  In your scenario there is no reason why the original object would not 
persist, so that really what is happening is that a copy of the original object 
is being made at the receiving end from matter that is present there.  I don't 
think that copying can be considered in the same light as taking the subway as a 
form of transportation.  

Consider taking a vacation to the Bernard's Star using this method.  You step 
into the transmitter and "zap", a complete description of your current state is 
sent beaming toward the star.  You are still standing in the transmitter.  No 
one would mistake the beamed description of you for the actual you.  Once the 
description reached Bernard's Star, it could be intercepted and decoded so that 
a copy of you would be created there.  Now there is the original you on Earth 
and the copy, which is physically several years younger than the original, since 
light takes several years to reach Benard's Star.  The vacation starts for the 
copy at Bernard's Star, but the original knows nothing about it back on Earth, 
at least until the holiday snapshots start arriving via the interstellar mail.

Best Regards,

Everett Rubel