Thread

1. captainbland · 1790421973 · focus · HN ↗

   Ok so imagine we set up two sets of babushca dolls. Each larger one has two smaller ones nested inside. The total mass of the two smaller ones between the two sets is equal in mass and they are configured to have the same centre of gravity. But crucially the individual masses of the inner dolls are different between the two sets. So maybe the innermost one is made of a denser material in set A and the middle one a less dense material and in set B vice versa. And let's also say in each case the dolls are all locked into position relative to the outermost one, so there's no "play" if you move it around to infer a difference from.

   From an outside mass/gravity point of view these are similar right? Yet the holographic universe theory seems to say we should be able to differentiate between the two sets of dolls purely based on space-time observations of the surface of the outer doll, despite each system having identical gravitational properties when viewed externally?

   But doesn't that suggest a contradiction between this theory and what we have observed about gravity?

   1. DarkNova6 · 1790423553 · focus · HN ↗

      There seems to be a grand motivation to fit a holographic model onto how the universe seems to behave.

      I recall a popular claim several years ago that we all lived in a hologram (whatever happened to that?).

      I bet this has nothing to do with string theorists trying to make their 2D models apply to actual physical observations…

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