<html><head></head><body><div><span title="msd001@gmail.com">Mike Dougherty</span><span class="detail"> <msd001@gmail.com></span> , 11/4/2014 10:33 PM:<blockquote class="mori" style="margin:0 0 0 .8ex;border-left:2px blue solid;padding-left:1ex;"><div class="mcnt"><div class="mcntgmail_extra">The way I understand the holographic universe, there's a 2d description of the information contained inside the 3d volume bounded by a sphere. If there is more information generated by any of the subspace, wouldn't the sphere necessarily increase in surface area to accommodate the increased complexity in the description of the bounded space?</div></div></blockquote></div><div><br></div><div>As far as I understand it, the boundary is arbitrary: it is a marker, not a thing. So if a bunch of extra information arrives inside, it corresponds to a change in the description on the boundary. But the location of boundary itself does not change. </div><div><br></div><br><div><blockquote class="mori" style="margin:0 0 0 .8ex;border-left:2px blue solid;padding-left:1ex;"><div class="mcnt"><div class="mcntgmail_extra"> The more complex and ordered the simulations (of any level) the larger the surface and therefore the more emptiness around the information-dense core. </div></div></blockquote></div><div><br></div><div>The Bekenstein bound places a limit on the amount of information inside a volume by the encoding capacity of the boundary. But if there is too much information in a small region you cannot make it stable by having lots of emptiness outside, since there is another boundary just around the core that bumps into the bound. A matter distribution does not avoid becoming a black hole just because there is a lot of nothing outside: it has to keep its density within a limited range instead. </div><div><br></div><br><div><blockquote class="mori" style="margin:0 0 0 .8ex;border-left:2px blue solid;padding-left:1ex;"><div class="mcnt"><div class="mcntgmail_extra">Does that remind anyone else of a description of an atom?</div></div></blockquote></div><div><br></div><div>No. :-)</div><div><br></div><div>Atoms are rather different: the reason for their size scale is the relative strength of the forces. Electron clouds have a size determined by how the electromagnetic force falls off and how strong it is relative to the electron mass. The size of the atomic nucleus is determined by the ratio between the strong and electromagnetic force, and the nucleon masses. </div><div><br></div><div>Note that there are nuclei as large as cities (neutron stars), and electron clouds you can hit with a car (metal objects) - as well as "naked" nucleons and electrons. This has nothing to do with fundamental physics. </div><div><br></div><div>(As you can tell, I am annoyed by people saying "but what is, man, our solar system/galaxy is like an atom... whoa" - I usually respond that planets/stars don't jump between orbitals and certainly doesn't follow the Schroedinger equation.)</div><div><br></div><br>Anders Sandberg, Future of Humanity Institute Philosophy Faculty of Oxford University</body></html>