Newton's law of gravitational attraction
in [Relativity]
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From: Jonah Thomas on 24 Sep 2009 15:11 PD <thedraperfamily(a)gmail.com> wrote: > You see, this is what separates you from science, Porat. > > You have it in your head that some basic notions that come into your > head MUST be true, and you simply do not have any way to verify > whether they ARE true. Scientists don't do that. They check > everything, every assumption to see if it really is true. > > Let's take the example of your notion that no daughter can be larger > than its mother. You insist that this MUST be true. A scientist would > test whether that really is true by creating an explicit test of that > assumption. The accelerator is a good example of that kind of test. > The accelerator is specifically designed to do (among other things) > collisions of light particles and to identify all the particles that > come out of those collisions, and it is very carefully designed to > rule out background events. > > So when a scientist sees in this test that heavy daughters can come > from light parents, the scientist will say, "Well, there's no arguing > with experiment. It appears that the statement that no daughter can be > bigger than its mother was just wrong." You, on the other hand, stick > with the rule you had in your head and insist that there must be > something wrong with the experiment or something else was going on > that masked the truth. Not to defend Porat, who is saying things I do not understand, but the behavior you describe is very common in physics, isn't it? For example, physicists generally believe in conservation of mass+energy and momentum, and angular momentum. So when they found an example where these were not conserved, they invented an undetectable particle, the neutrino, that was carrying away the stuff that was missing, or occasionally bringing in extra when there was a lack. And somebody got a nobel prize for confirming that the reaction that people thought would violate conservation of stuff really did happen. This was interpreted as "direct observation of neutrinos". I'm not saying they're wrong to believe in conservation of stuff even when they get examples where stuff disappears and they can't find it, or extra stuff sometimes appears out of nowhere. Just, they're doing what you accuse Porat of doing, and mostly nobody thinks they're wrong to do so. When experiments give results that disagree with their theories they usually decide that something else is going on that masks the truth.
From: PD on 24 Sep 2009 15:25 On Sep 24, 2:11 pm, Jonah Thomas <jethom...(a)gmail.com> wrote: > PD <thedraperfam...(a)gmail.com> wrote: > > You see, this is what separates you from science, Porat. > > > You have it in your head that some basic notions that come into your > > head MUST be true, and you simply do not have any way to verify > > whether they ARE true. Scientists don't do that. They check > > everything, every assumption to see if it really is true. > > > Let's take the example of your notion that no daughter can be larger > > than its mother. You insist that this MUST be true. A scientist would > > test whether that really is true by creating an explicit test of that > > assumption. The accelerator is a good example of that kind of test. > > The accelerator is specifically designed to do (among other things) > > collisions of light particles and to identify all the particles that > > come out of those collisions, and it is very carefully designed to > > rule out background events. > > > So when a scientist sees in this test that heavy daughters can come > > from light parents, the scientist will say, "Well, there's no arguing > > with experiment. It appears that the statement that no daughter can be > > bigger than its mother was just wrong." You, on the other hand, stick > > with the rule you had in your head and insist that there must be > > something wrong with the experiment or something else was going on > > that masked the truth. > > Not to defend Porat, who is saying things I do not understand, but the > behavior you describe is very common in physics, isn't it? > > For example, physicists generally believe in conservation of mass+energy > and momentum, and angular momentum. So when they found an example where > these were not conserved, they invented an undetectable particle, the > neutrino, that was carrying away the stuff that was missing, or > occasionally bringing in extra when there was a lack. > > And somebody got a nobel prize for confirming that the reaction that > people thought would violate conservation of stuff really did happen. > This was interpreted as "direct observation of neutrinos". > > I'm not saying they're wrong to believe in conservation of stuff even > when they get examples where stuff disappears and they can't find it, or > extra stuff sometimes appears out of nowhere. Just, they're doing what > you accuse Porat of doing, and mostly nobody thinks they're wrong to do > so. When experiments give results that disagree with their theories they > usually decide that something else is going on that masks the truth. Not quite, but I see where you're going. Momentum conservation was deduced from a number of observations, and then it was tested in thousands of applications after the rule was proposed. In an interesting case, though, momentum conservation seemed not to hold. So two candidate proposals were put forward: 1. Momentum is not conserved in all cases after all. 2. Momentum is conserved, but there is a yet undiscovered particle that is carrying away some of the momentum. Now, the key to the second is that you can't just leave it that. You have to find some OTHER way to verify the existence of that particle OTHER THAN deducing it from missing momentum. And so there were numerous experiments devised to do just that. The Nobel Prize was awarded for the first work that showed that unambiguously -- that neutrinos can be detected by some means other than by insisting that momentum be conserved. If you look at the Nobel award lecture, you'll learn what was involved. A similar thing is going on now with dark matter. There are two proposals on the table: 1. General relativity is wrong. 2. General relativity is right, but there is matter that is undiscovered and not accounted for. And once again, it is important to establish the presence of dark matter by some evidence OTHER THAN it makes general relativity hold. And so there are a number of experiments in progress to do just that. PD
From: Sam Wormley on 24 Sep 2009 15:32 PD wrote: > Momentum conservation was deduced from a number of observations, and > then it was tested in thousands of applications after the rule was > proposed. > > In an interesting case, though, momentum conservation seemed not to > hold. So two candidate proposals were put forward: > 1. Momentum is not conserved in all cases after all. > 2. Momentum is conserved, but there is a yet undiscovered particle > that is carrying away some of the momentum. > Now, the key to the second is that you can't just leave it that. You > have to find some OTHER way to verify the existence of that particle > OTHER THAN deducing it from missing momentum. And so there were > numerous experiments devised to do just that. The Nobel Prize was > awarded for the first work that showed that unambiguously -- that > neutrinos can be detected by some means other than by insisting that > momentum be conserved. If you look at the Nobel award lecture, you'll > learn what was involved. > > A similar thing is going on now with dark matter. There are two > proposals on the table: > 1. General relativity is wrong. > 2. General relativity is right, but there is matter that is > undiscovered and not accounted for. > And once again, it is important to establish the presence of dark > matter by some evidence OTHER THAN it makes general relativity hold. > And so there are a number of experiments in progress to do just that. > > PD Good explanation! Thanks
From: Jonah Thomas on 24 Sep 2009 17:52 PD <thedraperfamily(a)gmail.com> wrote: > Jonah Thomas <jethom...(a)gmail.com> wrote: > > For example, physicists generally believe in conservation of > > mass+energy and momentum, and angular momentum. So when they found > > an example where these were not conserved, they invented an > > undetectable particle, the neutrino, that was carrying away the > > stuff that was missing, or occasionally bringing in extra when there > > was a lack. > > > > And somebody got a nobel prize for confirming that the reaction that > > people thought would violate conservation of stuff really did > > happen. This was interpreted as "direct observation of neutrinos". > > > > I'm not saying they're wrong to believe in conservation of stuff > > even when they get examples where stuff disappears and they can't > > find it, or extra stuff sometimes appears out of nowhere. Just, > > they're doing what you accuse Porat of doing, and mostly nobody > > thinks they're wrong to do so. When experiments give results that > > disagree with their theories they usually decide that something else > > is going on that masks the truth. > > Not quite, but I see where you're going. > Momentum conservation was deduced from a number of observations, and > then it was tested in thousands of applications after the rule was > proposed. > In an interesting case, though, momentum conservation seemed not to > hold. So two candidate proposals were put forward: > 1. Momentum is not conserved in all cases after all. > 2. Momentum is conserved, but there is a yet undiscovered particle > that is carrying away some of the momentum. > Now, the key to the second is that you can't just leave it that. You > have to find some OTHER way to verify the existence of that particle > OTHER THAN deducing it from missing momentum. And so there were e that we do not understand yet. We really should not ignore that possibility. It could easily be that GR is right within broad limits but in our attempts to interpret the actions of distant galaxies from their EM radiation alone we have made some mistakes. And it could easily be that GR is wrong and also there is matter that is undiscovered and not accounted for. > And once again, it is important to establish the presence of dark > matter by some evidence OTHER THAN it makes general relativity hold. > And so there are a number of experiments in progress to do just that. I hope they do better than the experiments that detected neutrinos. > numerous experiments devised to do just that. The Nobel Prize was > awarded for the first work that showed that unambiguously -- that > neutrinos can be detected by some means other than by insisting that > momentum be conserved. If you look at the Nobel award lecture, you'll > learn what was involved. As I understand it, the original problem was that neutrons spontaneously change into protons plus electrons with a variable amount of measurable energy. So it was assumed there was an undetectable particle that carried off the extra energy etc. The assumption was that there would be a whole lot of these particles coming out of a nuclear reactor, so they looked for protons turning into neutrons plus positrons near the reactor. And they found a few protons turning into neutrons plus positrons there. Since protons are completely stable and never turn into anything else normally, they assumed what was making it happen was the undetectable particles. Why did they assume it was particles and not some sort of undetectable radiation? Why was it particles and not changes in the probability field that allows unlikely things to happen much more often? Because they were predisposed to particles. For the same reason that they preferred to think it was undetectable particles instead of undetectable elves. It fit their prejudices. But that isn't exactly a bad thing. They're physicists and they ought to be prejudiced in favor of undetectable particles over undetectable elves. There's nothing really wrong here. It's proper that when they find an experiment that contradicts a rule they believe is never contradicted, they should decide there's an undetectable fudge factor that secretly restores the rule. That's how physics is done, and other sciences too. And they might as well think it's particles instead of, say, waves, because if it's a particle then each individual particle that gets created can get destroyed in a single interaction. Waves would leave little bits of wave slopping around, radiating off to the farthest star or beyond. Particles tie up the loose ends neater. Tidy. And with no evidence whatsoever to tell them what the undetectable entity is like, they might as well assume it's the sort of thing they've been looking for. In those days a lot of physicists were looking for new particles, so it only makes sense to call the undetectable entity one. > A similar thing is going on now with dark matter. There are two > proposals on the table: > 1. General relativity is wrong. > 2. General relativity is right, but there is matter that is > undiscovered and not accounted for. Or: 3. There are other things going on out in distant space that we do not understand yet. We really should not ignore that possibility. It could easily be that GR is right within broad limits but in our attempts to interpret the actions of distant galaxies from their EM radiation alone we have made some mistakes. And it could easily be that GR is wrong and also there is matter that is undiscovered and not accounted for. > And once again, it is important to establish the presence of dark > matter by some evidence OTHER THAN it makes general relativity hold. > And so there are a number of experiments in progress to do just that. I hope they do better than the experiments that detected neutrinos. But I think they're right to look. "There is nothing like looking, if you want to find something. .... You certainly usually find something if you look, but it is not always quite the something you were after. --J.R.R. Tolkien
From: doug on 24 Sep 2009 18:58
Jonah Thomas wrote: > PD <thedraperfamily(a)gmail.com> wrote: > >>Jonah Thomas <jethom...(a)gmail.com> wrote: > > >>>For example, physicists generally believe in conservation of >>>mass+energy and momentum, and angular momentum. So when they found >>>an example where these were not conserved, they invented an >>>undetectable particle, the neutrino, that was carrying away the >>>stuff that was missing, or occasionally bringing in extra when there >>>was a lack. >>> >>>And somebody got a nobel prize for confirming that the reaction that >>>people thought would violate conservation of stuff really did >>>happen. This was interpreted as "direct observation of neutrinos". >>> >>>I'm not saying they're wrong to believe in conservation of stuff >>>even when they get examples where stuff disappears and they can't >>>find it, or extra stuff sometimes appears out of nowhere. Just, >>>they're doing what you accuse Porat of doing, and mostly nobody >>>thinks they're wrong to do so. When experiments give results that >>>disagree with their theories they usually decide that something else >>>is going on that masks the truth. >> >>Not quite, but I see where you're going. >>Momentum conservation was deduced from a number of observations, and >>then it was tested in thousands of applications after the rule was >>proposed. >>In an interesting case, though, momentum conservation seemed not to >>hold. So two candidate proposals were put forward: >>1. Momentum is not conserved in all cases after all. >>2. Momentum is conserved, but there is a yet undiscovered particle >>that is carrying away some of the momentum. >>Now, the key to the second is that you can't just leave it that. You >>have to find some OTHER way to verify the existence of that particle >>OTHER THAN deducing it from missing momentum. And so there were > > e that we do > not understand yet. We really should not ignore that possibility. It > could easily be that GR is right within broad limits but in our attempts > to interpret the actions of distant galaxies from their EM radiation > alone we have made some mistakes. > > And it could easily be that GR is wrong and also there is matter that is > undiscovered and not accounted for. > > >>And once again, it is important to establish the presence of dark >>matter by some evidence OTHER THAN it makes general relativity hold. >>And so there are a number of experiments in progress to do just that. > > > I hope they do better than the experiments that detected neutrinos. You really should read some actual science some time. The experiments that detect neutrinos were well done. You seem to be totally ignorant of them. > > >>numerous experiments devised to do just that. The Nobel Prize was >>awarded for the first work that showed that unambiguously -- that >>neutrinos can be detected by some means other than by insisting that >>momentum be conserved. If you look at the Nobel award lecture, you'll >>learn what was involved. > > > As I understand it, the original problem was that neutrons spontaneously > change into protons plus electrons with a variable amount of measurable > energy. So it was assumed there was an undetectable particle that > carried off the extra energy etc. > > The assumption was that there would be a whole lot of these particles > coming out of a nuclear reactor, so they looked for protons turning into > neutrons plus positrons near the reactor. And they found a few protons > turning into neutrons plus positrons there. Since protons are completely > stable and never turn into anything else normally, they assumed what was > making it happen was the undetectable particles. > > Why did they assume it was particles and not some sort of undetectable > radiation? Why was it particles and not changes in the probability field > that allows unlikely things to happen much more often? Because they were > predisposed to particles. For the same reason that they preferred to > think it was undetectable particles instead of undetectable elves. It > fit their prejudices. > > But that isn't exactly a bad thing. They're physicists and they ought to > be prejudiced in favor of undetectable particles over undetectable > elves. There's nothing really wrong here. It's proper that when they > find an experiment that contradicts a rule they believe is never > contradicted, they should decide there's an undetectable fudge factor > that secretly restores the rule. That's how physics is done, and other > sciences too. And they might as well think it's particles instead of, > say, waves, because if it's a particle then each individual particle > that gets created can get destroyed in a single interaction. Waves would > leave little bits of wave slopping around, radiating off to the farthest > star or beyond. Particles tie up the loose ends neater. Tidy. And with > no evidence whatsoever to tell them what the undetectable entity is > like, they might as well assume it's the sort of thing they've been > looking for. In those days a lot of physicists were looking for new > particles, so it only makes sense to call the undetectable entity one. > > >>A similar thing is going on now with dark matter. There are two >>proposals on the table: >>1. General relativity is wrong. >>2. General relativity is right, but there is matter that is >>undiscovered and not accounted for. > > > Or: > > 3. There are other things going on out in distant space that we do > not understand yet. We really should not ignore that possibility. It > could easily be that GR is right within broad limits but in our attempts > to interpret the actions of distant galaxies from their EM radiation > alone we have made some mistakes. > > And it could easily be that GR is wrong and also there is matter that is > undiscovered and not accounted for. > > >>And once again, it is important to establish the presence of dark >>matter by some evidence OTHER THAN it makes general relativity hold. >>And so there are a number of experiments in progress to do just that. > > > I hope they do better than the experiments that detected neutrinos. Repeating your ignorance of science does not help. But > I think they're right to look. > > "There is nothing like looking, if you want to find something. .... You > certainly usually find something if you look, but it is not always quite > the something you were after. --J.R.R. Tolkien |