<div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif">On Wed, Sep 16, 2020 at 9:18 PM Stuart LaForge via extropy-chat <<a href="mailto:extropy-chat@lists.extropy.org">extropy-chat@lists.extropy.org</a>> wrote:</span><br></div></div><div class="gmail_quote"><div dir="ltr" class="gmail_attr"><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><font size="4">General<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>Relativity and Quantum Mechanics are not compatible theories, although both<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>work very well within their realm of applicability, General Relativity<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>works great for gravity but can say nothing about the nuclear forces,<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>quantum mechanics can say a lot about the nuclear forces but can't say<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>anything about gravity.</font></blockquote>
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<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>Dirac managed to combine Special Relativity and Quantum Mechanics and the math correctly predicted antimatter</i></blockquote><div><br></div><font size="4">Yes and Dirac was brilliant<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">, but the</span> Dirac <span class="gmail_default" style="font-family:arial,helvetica,sans-serif"></span>Equation<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> says nothing about gravity because </span>Special Relativity <span class="gmail_default" style="font-family:arial,helvetica,sans-serif"></span>says nothing about gravity or about objects that are accelerating, that's why it's called special, it only works in special circumstances. It took another<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> 10 years of backbreaking work f</span><span style="font-family:arial,helvetica,sans-serif">or Einstein to figure out General Relativity <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">which could</span> deal with general situations <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">like those</span> with gravity and acceleration<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">.</span><span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span></span></font></div><div class="gmail_quote"><div> <br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span><i>There might be some clever hack that allows GR and QM to similarly mesh.</i><br></blockquote><div><br></div><font size="4">Maybe, but that has been the Holy Grail of Physics for a century and a lot of geniuses have tried to find it including Einstein and Dirac and they all ended up with nothing, so I believe it'll take more than just a simple hack, it will probably<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>take a change in the way we think about things as profound is the quantum revolution of 1900. I just wish I knew what it was. </font><br><br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"><i>> </i></span><i>I don't think it is a lack of theories of quantum gravity that is the problem. There are several theories already in circulation including several versions of string theory. The problem is none can make testable predictions.</i></blockquote><div><br></div><div><font size="4">If it can't make testable predictions <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">then </span>it's not a theory it's philosophical musings<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">, even string theory fans say it's a theory on how to someday get a theory about gravity. But even then I don't know how they'd test it. </span></font></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><i> <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>How do you go about deciding the validity of a theory that makes predictions about things in a physical regime that cannot be observed in nature or reproduced in a laboratory?</i></blockquote><div><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><font size="4">Nobody knows and that's the problem. </font></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><i><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>We need more progress in the experimental side of things I think.<br></i></blockquote><div><br></div><div><span class="gmail_default" style="font-family:arial,helvetica,sans-serif"></span><font size="4">Yes but easier said than done. We could quickly make progress if we had a particle accelerator that was powerful enough to probe the Planck scale, but with current technology such a machine would have to be at least as big as the solar system, and it would be difficult to get congressional funding for that. In my opinion the second best way would be to build machines to more closely examine the behavior of neutrinos because they do seem to show some small cracks in the standard model of physics, such experiments are not cheap, nothing in big physics is, but they're not so expensive as to be ridiculous. Also, just a few days ago there was a report that a pseudo-atom consisting of an electron and a antielectron admitted microwaves that very slightly deviated from the predictions of the most accurately tested theory in all of science, Quantum<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>Electrodynamics.<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>If this is confirmed it could really be important, it could give us a clue. </font></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><font size="4">
><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">></span> no physicist has ever seen a mathematical hypotenuse, however they<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>have seen lines that connect diagonal corners on cardboard squares.</font></blockquote>
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<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>As an approximation perhaps, but not as a scientific experiment to look for granularity in space. Why would you use something made of atoms which are known to be discrete to test the existence of the <br>
continuum of real numbers?</i></blockquote><div><br></div><div><font size="4">Because <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">matter is</span><span style="font-family:arial,helvetica,sans-serif"> the only thing we know how to make scientific instruments or a machine of any sort out of<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">, and like it or not matter is made of atoms. </span></span></font></div><div> <br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><i><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">></span>The Pythagorean theorem is a property of Euclidean space and not particles. That's why I suggested my <br>
interferometry experiment. </i></blockquote><div><br></div><font size="4">To conduct a interferometry experiment you need a interferometer, and they are made of matter. And so are Gamma Ray orbiting telescopes. Quantum mechanics predicts that if space-time really is discrete and not continuous then high energy high frequency electromagnetic waves will travel at a slightly slower speed than lower frequency lower energy waves. But a few years back a 2.1 second long Gamma Ray burst occurred 7.3 Billion light years away, and satellites were able to determine that 2 photons coming from that burst had the same speed to one part in 100 Million Billion even though one of the photons had 1 million times more energy than the other. So Einstein won again, as usual. It's just not looking good for a discrete space time.</font><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><font size="4">
><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">></span> Mathematics is the language of physics but mathematics is not physics.<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>English is a language too but the English word "*cow*" cannot give milk.</font></blockquote>
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<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>But a virtual cow can give virtual milk and a virtual man could drink <br></i></blockquote><div><br></div><font size="4">Agreed, but the very fact that they serve in different realms means that a virtual cow <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">is</span> not identical to a physical cow, and the virtual cow<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> couldn't exist without physics. That's why I think physics is more fundamental than mathematics. </span></font></div><div class="gmail_quote"><br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><i>
<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>it and they would all three be made out of math and information.</i></blockquote><div><br></div><font size="4">It's not turtles all the way down, eventually you get down to matter. To make a virtual cow you have to process information, and to process information you need to make a Turing Machine, and Turing Machines<br>are made of matter. And matter is made of atoms.<br><br><span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>John K Clar<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">k</span></font><div> </div></div></div>