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If you read my posts, I explained that I meant objectivity only in the sense of measurable outcomes for social groups and their members. Twice. And clarified how it was not a religious or metaphysical take on intrinsic moral good. Have a good day, or night, depending on time zone.

Let me add a few thoughts from an entirely godless entity who next monday will be celebrating his 19th wedding anniversary to a devout Christian. Everybody needs some sort of world model within their heads to assess the consequences of their actions before they commit to them. Some models give different results in different aspects of life. But they are vital since they are integral part and parcel of the full package of that person's personality. Trying to deprive an adult of such a vital part of their being can only diminish them. My wife is more than I deserve as the full package and therefore I have learned to respect her religious views, as she has learned to accept my entirely materialist world view. A second lesson I have learned is that while her religion tends sometimes to give her a more optimistic attitude than I might feel certain situations merit, that isn't such a bad thing. It does at least make me examine whether I'm taking too safe an approach at times. The diversity of viewpoints is a good thing and makes us stronger together than apart. And there are areas where I know her judgment is simply better than mine. Particularly in assessing the dynamics going on between the people around us and how they are likely to respond to our activities. Science is as yet generally a very poor guide in such matters. Of course organised religion must be strongly opposed where it tries to prevent the proper teaching of sciences, etc., but I think we should take care when we consider beeing so vehement towards individuals who differ from us only in their private personal philosophy.

Different observers, no contradictions. The crucial fact here is that Alice does not know the result of her measurement before she makes the measurement. Same with Bob.

I would venture to say the US electoral system is not operating at maximum efficacy.

If you really want to accomplish a specific goal, you've already got the best motivation there is. Nothing gets us going more than doing something we really want to do. If you really want it but it's not happening, WHY isn't it happening? If you're like a lot of folks, you're somehow telling yourself it's not going to happen. You're programming your brain with negativity, so you don't get a positive outcome. You started working on your app "a few years ago", and I'll bet you've semi-given-up on it several times by telling yourself many different negative things. A lot of folks are taught that being your own cheerleader is vain and egotistical, and that's a shame because nobody knows your capabilities better than you. It may seem weird at first, but looking in the mirror every morning and reminding yourself how lucky you are to know what you really want to do is a great positive step towards motivation. And do you know how hard it is for most people to stop drinking or smoking?! You're amazing! And you live in a country that realizes you have much to offer that has nothing to do with your disability. And don't forget that you're a self-sufficient person as well, able to live on your own at 25 years old in these modern times. Bravo! Do me a favor, will you? If you can, put your arms up in the air like a "V" above your head, and imagine a whole stadium full of people are chanting your name and applauding, acknowledging the hardships you've faced, and admiring the fact that you still want to engage with the people around you and move on to your next goals. We're cheering for you because you deserve it, you're a very good person, and we all want to see you succeed. We want to see this app you've been telling us about for the last few years, and we're getting just as excited as you!

I think, they all agree that particle falls through the horizon. They disagree only on the timing of this event: for one, it happens in a finite time, for the other - infinite.

However, it happens all the time. A car moves as seen by a person standing outside, and it does not move as seen by its passenger. No contradiction.

There is a dictum “Follow the money”. Where did this guy get the money to launch a second attempt at a Congressional campaign? Who is covertly paying him? What interests does he really represent ? Some of those answers are alluded to in a photo of a document shown at the end of that video clip I linked. It shows details of filings in Florida for an LLC called Devolder, a holding company which magically transformed George Santos from a penniless deadbeat who had been twice evicted for non-payment of rent in 2017, into a millionaire by 2020. One of the principal investors in this LLC appears to be an associate of a Russian oligarch closely allied to Vladimir Putin. And by a curious coincidence George Santos is an outspoken critic of US support for Ukraine, and is a sympathetic apologist for Putin . “The best poliiticians that money can buy” - as they say.

Just want to throw in here (as an uninvolved reader) that you all seem to be tacitly equating religion with theism. But these are not the same things at all - not all religions are theistic in nature. I think it is important to distinguish these concepts more carefully.

You cannot ‘separate’ nearby gravitational wells neatly, because gravity is non-linear - spacetime in the Earth-Moon system is not simply the sum of ‘Earth gravity well’ + ‘Moon gravity well’, but something more complicated (though GR effects are quite small here). The same is true for all other planets in our solar system, since they are all subject to the gravity of the Sun. Of course, that goes without saying - the entirety of physics is about making models that describe aspects of the world around us. We don’t do philosophy or metaphysics or religion here, so everything that is being talked about in the physics section of this forum has to do with models. And whatever idea you have in mind about gravity is also a hypothesis about gravity, and not gravity itself. But here’s the point - GR has been extensively tested, and found to be in excellent agreement with experiment and observation. So we can regard the model as valid within its domain of applicability, and thus extract predictions from it. Now, if you take the ‘time’ out of spacetime, thus reducing the universe to three dimensions, then GR tells us very clearly what would happen so far as gravity is concerned. As such, if you claim that gravity still works in 3D in the exact manner as we can observe around us, then the onus will be on you to present a mathematically self-consistent model that shows this, and we shall be happy to take a look at it. Of course it isn’t. That’s been known for at least the past 50+ years! I don’t know why you use the word ‘admitting’, as if this is something that secretive and kept hidden. It isn’t. Alternative theories of classical gravity, as well as theories of quantum gravity, are probably the two most active areas of research in modern theoretical physics. Just search for some related terms of arXiv, and see yourself the amount of hits you get. So yes - the idea that the domain of applicability of GR might be limited even within the classical regime, and thus that it might only be a special case of something more general, is most definitely conceivable, and is being actively researched; there is a very large number of alternative models in existence. Do note though that when doing a direct comparison, none of these models - with the possible exceptions of relativistic MOND and Einstein-Cartan gravity - come even close to the versatility and success of GR. Also do note - and this is important - that the domain of applicability of a model being limited is not the same as that model being wrong. We still use Newtonian gravity extensively to model scenarios where relativistic effects can be neglected, so the model continues to be right within its domain of applicability, even though we have had GR for over a century. It’s just that this domain is limited, and we have a pretty good idea exactly where those limits are. The same will eventually also be true for GR, though at the moment we have only a very rough idea where the limits might be, and only some educated guesswork about what lies beyond these. Within the classical domain, it is very unlikely that any successful model of gravity will have a notion of time that is substantially different from that of Einsteinian spacetime, because any such theory will need to preserve local Lorentz invariance (and thus CPT invariance), which puts stringent bounds on what such models can look like. There are also more fundamental reasons based in topology that dictate why GR looks the way it does, so the notion of spacetime isn’t just a wild guess. The domain of quantum gravity is another matter entirely though - it is not just possible, but nearly certain, that we will have to fundamentally rethink our notions of both time and space to make quantised gravity work. Note that GR would be the classical limit of any such model. So then, why is the GR definition a problem for you? It works really well.

I see you've offered no evidence. Primitive tribal societies had power structures, imposed by the politicians of the day. And they would use religion to keep control whenever the chance presented itself. But primitive tribes usually had shamanist disorganised beliefs, and structure in religion didn't appear till society got bigger. And society got bigger because of farming, not religion. Religion just fed off what was there, there's no evidence that it led the way.

That's a weird question to even contemplate. The briefiest look at history will tell you that the early religions that were around when civilisation was in it's infancy were hugely vicious and destructive in nature. Just like the rest of society was back then. Even if you could isolate one or two that were less agressive and destructive, that doesn't convey credit on religion as a whole. Of course we would have civilisation without religion. Probably much sooner.

As fast as the electrons can get out of their way! 😊

Important cosmology update

I may have been not quite precise in my statement. Galilean or not is not coded in the force law though. It's almost all in the (mass)x(acceleration) of Newton's 3rd law. But not all... To be more precise, the force law should comply with certain constraints to be compatible with the whole Galilean group (isotropic, translation-invariant). So any force law that's of the form, \[ \boldsymbol{F}_{ij}=\boldsymbol{F}_{ij}\left(\left\Vert \boldsymbol{r}_{i}-\boldsymbol{r}_{j}\right\Vert \right) \] for particles i and j, would be compatible with the full Galilean group, \[ \boldsymbol{r}'=R\boldsymbol{r}-\boldsymbol{v}t+\boldsymbol{b} \] \[ t'=t \] where \( \boldsymbol{b} \) is a fixed translation, \( \boldsymbol{v} \) is a fixed velocity (Galilean boost), and \( R \) is a fixed rotation matrix, \[ RR^{t}=I \] \[ \det R=+1 \] \( I \) being the identity matrix. The matrix \( R \) codes a possible change of orientation between frames. There are velocity-dependent forces (magnetic) that can be made compatible with special relativity, but not with Galilean relativity. The whole shebang: https://en.wikipedia.org/wiki/Galilean_transformation#Galilean_group

Just as you quoted me, I said "I've never seen any . . . . blah blah " I didn't say I was conviced it wouldn't work. I'm seeing no signs that it can. That doesn't rule anything out, but some pretty drastic advances will need to be made, and there doesn't seem to be much optimism out there in people studying and commenting on it. One thing I did notice was that the HiPer concept needs equipment made of specialised neodymium glass, which is no longer being made. That's true, but it's really just stating that nobody can know the future. There certainly is a theoretical route to it, but nobody can say now whether there will be an insurmountable blockage on the way. They faced the same problem with the first steam trains, nobody knew if humans would be able to breath at speeds faster than horses can run. And before the first powered flight, there would have been huge scepticism. The market for energy is so huge, that if the financial institutions get a sniff that a fusion method is a goer, it's likely to get a huge investment boost. At the moment, the investment sums sound big, but when you compare them to the total energy market, they are miniscule.

That thread was about the NIF, which isn’t an approach that was designed with commercial energy generation in mind. So that thread isn’t discussing the question raised here. But AFAIK nobody yet has an answer to “How to construct economical fusion reactors?” since nobody has built one yet, and there’s no guarantee that any current approach will get there.

Earth species evolved sensors that detect various phenomena that helped them survive to reproduce, such as eyes that sense light, and ears and skin that can determine various sound vibrations or changes in temperature. All these stimuli existed first, and Earth life adapted to sense them to varying degrees. Think of it this way, there are parts of the light spectrum most humans can't see, like ultraviolet. UV light still exists even if we can't see it.

Yes. Hitler wasn't all bad. He made the trains run on time, built motorways and handy little air cooled cars, and kitted his troops out in some pretty snazzy uniforms. Unfortunately, he did have his little faults as well. So if someone had thrown him out with the bathwater when he was a baby, the world would be a bit nicer now. Religion is an obnoxious baby that grows bigger, takes over peoples minds, and becomes self-supporting by indoctrination, quite like Hitler. We can get the good bits of religion without the indoctrination of the next generation.

I'm aware about the observational evidence and I wouldn't propose a theory inconsistent with it. I have to make a correction: the test with the clock on the Moon (and one on the Earth) is a test for both GR and SR. The clocks would be subjected to both kinematic and gravitational time dilation. The test with a clock on the Moon I suggested, is a kind of test that was never done, so don't treat it as trivial. As far as I know we never tested GR+SR measuring and computing time dilation for 2 clocks situated in separate gravitational wells. All our tests were inside Earth's gravity well, including the GPS clocks on orbit. The Moon is orbiting the Earth but it is massive, having its own gravitational well. This is the novelty. And it can be done in the next years. Why we shouldn't do it? Aha, there you said it, the model can no longer function, so GR/Einsteinian definition of time is required for the model, not for the gravity itself. You also: Of course not. How could you think that? admitted that the current relativity is not the ultimate theory for gravity, so you are admitting that it is conceivable to have a new & better theory/model, maybe with a different concept/understanding of time. So, as long as there is change, we can (and we kind of need) to define time. The way we define and use it can vary, so there is no need to cling on the current GR definition or any particular definition. As long as we can use it successfully, any definition works. I just remembered something: if GR definition of time is the "true" one, our future is already "written"?

Then shut up and calculate...