tag:blogger.com,1999:blog-4637778157419388168.post3924386166051474621..comments2024-03-21T09:01:08.175-07:00Comments on Physics with an edge: Dark matter contradicts itself.Mike McCullochhttp://www.blogger.com/profile/00985573443686082382noreply@blogger.comBlogger14125tag:blogger.com,1999:blog-4637778157419388168.post-39765290597955914472015-05-03T04:47:50.369-07:002015-05-03T04:47:50.369-07:00But why does a high momentum imply there would be ...But why does a high momentum imply there would be a force between dark matter clouds and what force specifically? Seems to me it doesn't follow.Anonymoushttps://www.blogger.com/profile/00324960796340438261noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-71744553230924859512015-05-03T02:07:13.853-07:002015-05-03T02:07:13.853-07:00I appreciate your comments, but :) in order to kee...I appreciate your comments, but :) in order to keep the halo spread out, you have to give the hypothesised dark matter particles a lot of KE/momentum, so centrifugal forces keep them spread out in orbit. This means when 2 DM clouds hit there should be a force, a real one. This study shows there isn't one. The simplest explanation then is that there's no DM.Mike McCullochhttps://www.blogger.com/profile/00985573443686082382noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-88494701680924119612015-05-02T11:07:22.617-07:002015-05-02T11:07:22.617-07:00But this study was only sensitive to real forces, ...But this study was only sensitive to real forces, not a lack of them which is the reason CDM wouldn't collapse beyond halos. You can call it an apparent force but it's not a force at all. It's a lack of momentum exchange which causes halos to be supported under their own angular momentum. Just like there is no real repulsive force keeping the planets out of the Sun, only conservation of angular momentum. That's not a repulsive force and it wouldn't show up in this study. Anonymoushttps://www.blogger.com/profile/00324960796340438261noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-38584662652858497082015-05-02T05:53:48.916-07:002015-05-02T05:53:48.916-07:00My point still stands: the apparent repulsive forc...My point still stands: the apparent repulsive force, whatever it is, has to be balanced by mutual gravity. This is a self-attraction, but the study showed that if dark matter is there, then it can't self-interact..Mike McCullochhttps://www.blogger.com/profile/00985573443686082382noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-29494203960132702092015-05-02T05:51:38.174-07:002015-05-02T05:51:38.174-07:00This comment has been removed by the author.Mike McCullochhttps://www.blogger.com/profile/00985573443686082382noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-78846401967999738452015-05-02T04:49:22.014-07:002015-05-02T04:49:22.014-07:00Also your claim was that these results should have...Also your claim was that these results should have shown some sort of repulsive force, now you claim this repulsive force is not a real one but the dark matter not losing energy. But that's exactly what they wouldn't detect, it's the null hypothesis for forces. There is no contradiction here.Anonymoushttps://www.blogger.com/profile/00324960796340438261noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-51392744617244722472015-05-02T04:41:01.907-07:002015-05-02T04:41:01.907-07:00But you don't have to put energy in by hand. N...But you don't have to put energy in by hand. N-body simulations can form galaxies out of primordial fluctuations, there is no tuning of the energy of the dark matter particles at any point. The energy they gain is gravitational potential.<br /><br />Forgive me but more than a few models can re-derive the Tull-Fisher relationship, which isn't exact to begin with. A much better test would be actually predicting rotation curves and velocity distributions in ellipticals.Anonymoushttps://www.blogger.com/profile/00324960796340438261noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-26059298024250543122015-05-02T03:15:03.538-07:002015-05-02T03:15:03.538-07:00Dark matter feels gravity so it should converge to...Dark matter feels gravity so it should converge to a point. Modellers avoid this by saying the dark matter can't lose heat by radiation so it buzzes around like bees around a hive and the inertial/centrifugal apparent force is like a repulsion that keeps it out in the halo. The trouble with this is you have to put this energy in by hand checking all the time that combined with gravity it makes general relativity fit the rotation data. Computers make this delicate act possible. My point is there is no physical reason (beyond saving GR) that says 'it must be this value' (it's wrong to assume in advance that GR is right, as they do). With MiHsC there's only one possible prediction, and it works.Mike McCullochhttps://www.blogger.com/profile/00985573443686082382noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-63926380951797244902015-05-01T14:28:11.887-07:002015-05-01T14:28:11.887-07:00CDM doesn't include any repulsive forces and y...CDM doesn't include any repulsive forces and yet in simulation it reproduces large scale structure and halo concentrations extremely well. What are you basing the claims that dark matter requires a repulsive potential on? It's not part of standard theory. Anonymoushttps://www.blogger.com/profile/00324960796340438261noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-34552886965508207612015-04-05T15:52:35.705-07:002015-04-05T15:52:35.705-07:00Maybe you could communicate with 'Star Drive&#...Maybe you could communicate with 'Star Drive' directly via PM at NSF. Impression I get is that the Eagleworks team is collectively very busy with the 'hands on' stuff. Anonymoushttps://www.blogger.com/profile/06388738042629653874noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-66282817183818621282015-04-05T13:58:20.311-07:002015-04-05T13:58:20.311-07:00Thanks. Interesting, but I'd really like to se...Thanks. Interesting, but I'd really like to see the formula/method they're using (how many assumptions & adjustable parameters?) & what they predict for all the experiments (like the Tables I've shown). Have they published their formula & these predictions somewhere that I don't know about?Mike McCullochhttps://www.blogger.com/profile/00985573443686082382noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-73477691423357452162015-04-05T13:03:08.419-07:002015-04-05T13:03:08.419-07:00Mike -
Now 'Star Drive' (guy on Eaglework...Mike -<br /><br />Now 'Star Drive' (guy on Eagleworks team) has dropped his own bombshell at NSF. Seems they have been doing a *lot* of testing and thinking over there lately. Some of the predictions are...impressive. Might be worth a look n your part.Anonymoushttps://www.blogger.com/profile/06388738042629653874noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-4079487148581451562015-04-05T04:43:33.059-07:002015-04-05T04:43:33.059-07:00Thanks, interesting. I don't believe the warp ...Thanks, interesting. I don't believe the warp stuff & they should have documented it better so people can tell how robust it is, but the expt is interesting (tho' the exponential dependence of force on power is different to emdrive). Unruh waves r partly EM and I've said b4 they might be open to interference. This might be a way to do it.<br /><br />No crazy engineer yet. I'd like to think about it all a bit more, b4 considering an emdrive build, because with MiHsC I may see a way to simplify or enhance things..Mike McCullochhttps://www.blogger.com/profile/00985573443686082382noreply@blogger.comtag:blogger.com,1999:blog-4637778157419388168.post-70473441329011684592015-04-03T18:53:35.873-07:002015-04-03T18:53:35.873-07:00This ones a bit 'out there,' but it seems ...This ones a bit 'out there,' but it seems to be some species of EM Drive, and the guy did post a result table.<br /><br />http://www.paresspacewarpresearch.org/Projet_Space_Warp/Experiment_5.htm<br /><br />Might be worth a quick look to you. <br /><br />Also, Doctor Rodal just dropped a bit of a bombshell on the approach we were looking at the NSF forum.<br /><br />Any luck finding somebody to build you your very own EM Drive yet?Anonymoushttps://www.blogger.com/profile/06388738042629653874noreply@blogger.com