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A comment on Twisted graphene has become the big thing in physics. Parent comment

Re:Twisted graphene has become the big thing in physics by ouid on Friday May 03, 2019 @02:55AM (#19816165)
no, what I'm talking about is more like a perfectly circular orbit around the sun, where the direction of the acceleration is always exactly perpendicular to the motion.
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Re:Twisted graphene has become the big thing in physics by soulofmischief on Friday May 03, 2019 @05:43AM (#19816884)
But there is no perfectly circular orbit around the sun. The mass of the two bodies causes the center of mass to be slightly off center from the sun, and both the sun and earth orbit around this center of mass in a fashion that AFAIK loses energy.
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Re:Twisted graphene has become the big thing in physics by garmaine on Friday May 03, 2019 @06:02AM (#19816961)
If the two objects were either perfect spheres or tidally locked, then a circular orbit would continue forever. There are no losses due to pure motion in a vacuum.
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Re:Twisted graphene has become the big thing in physics by Arbalest on Friday May 03, 2019 @06:43AM (#19817146)
I thought the theme of my reply is that we're not talking about theoretical constructs, but instead reality... Space is not a vacuum, just much lower pressure than on earth.
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