Index Key:  PHY053
Author:     dbias
Subject:    Safe Space
Text:       I do not understand why space is not considered a tangible 
substance, if it has elastic properties.

Response #:  1 of 3
Author:      Sam Bowen
Text:        Indeed, several people have looked for the manifestation of this 
which would be gravitons, the excitations of the gravitational field.  So far 
there is no good evidence that we have seen any after almost 30 years of 
looking.  Either they do not exist, or nothing is happening to produce them 
near by.  The effects you are taking about are very small and would be very 
difficult to detect near a regular planet.  Near a black hole they can be 
large, we think.

Response #:  2 of 3
Author:      Arthur Smith
Text:        A new experiment that is designed to detect even extremely weak 
gravitational waves has been recently proposed, and may soon be built - this 
is called LIGO, or laser interferometric gravitational wave observatory (I 
think).  If they exist, this experiment should see them within the next few 
years.

Response #:  3 of 3
Author:      mooney
Text:        Actually, gravity has not been shown to be an inertial effect.  
What is usually said is that the effect of gravity cannot be distinguished 
from the effect of an acceleration from any other source:  a force is a force.  
It is a pretty strong statement, but I do not think it implies all that you 
are saying it implies.