From: bergervo@iae.nl   
      
   On 10/31/2018 7:05 AM, Sabbir Rahman wrote:   
   > On Friday, August 17, 2018 at 10:07:39 AM UTC+3, Phillip Helbig (undress to   
   reply) wrote:   
   >> In article <2c0366cf-d2b2-4d5e-ad1b-47cd027030e5@googlegroups.com>,   
   >>  writes:   
   >>   
   >>>> If you had two negative masses they would attract. Because with the   
   >>>> negative mass acceleration is towards a positive mass this experiment   
   >>>> may not be able to determine if antimatter is really negative mass.   
   >>   
   >> If I recall correctly, not long ago Steve Carlip pointed out here that   
   >> positive mass attracts everything, including negative mass, and negative   
   >> mass repels everything.   
   >   
   > I am a little bit late to join this thread (sorry), but I wanted to make a   
   > few important points.   
   >   
   > In general people have to be more specific when they refer to "negative   
   > mass". There are three mass types that enter into Newton's law of   
   > gravitation for example - inertial, active and passive mass. If the signs of   
   > these three masses are I, A and P respectively, then the particle type can   
   > be specified by (I,A,P) - so there are 8 types, (+++), (++-), (+-+), (+--),   
   > (-++), (-+-), (--+) and (---). Obviously (+++) corresponds to ordinary   
   > matter and the remaining 7 have at least one kind of negative mass, so you   
   > need to be specific which type you mean. If you mean by negative mass type   
   > (---), which is the one allowed by the WEP, then this will indeed fall   
   > `downwards'. This type is also repels itself.   
   >   
   > Newton's law depends only on the product IP, so there are actually only 4   
   > types of particle in terms of mutual interactions.   
      
   Why is that? In Newtons laws there is the force depending on:   
   1 Mass creating the gravitational field (your active mass, presumably).   
   2 The mass acting as test particle feeling the force (passive mass).   
   3 Inertial mass determining which acceleration results from the force.   
      
   So the acceleration that occurs depends on three kinds of mass. Or do   
   you work with other subdivisions?   
      
   --   
   Jos   
      
   --- SoupGate-Win32 v1.05   
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