I'm just reporting what happened, and got some good info there that sounded highly plausible
Sounds highly plausible to whom? To you. Doesn't sound in the slightest bit plausible to me and I'd wager the same about anyone else who has studied physics to any great depth.
In an infinitely large universe whose space neither expands nor contracts, sprinkle an infinity of galaxies. Within some section of this universe let all of the galaxies approach one another. This is possible in principle. The size of the section is arbitrary; make it the size of the universe. Now all of the galaxies in the universe approach one another, yet there is no cosmic center or edge. Now play the film backwards, so to speak, to find that all of the galaxies in the universe can recede from one another, with no cosmic center or edge.
You only believe this plausible because you have no clue of the data you're supposed to be explaining. Galaxy dynamics cannot be explained by simply running gravitational collapse backwards. The data contradicts your claim.
Removing the notion of expanding space solves the flatness problem, he said, for then space can be flat by default.
It could but we reason people say its expanding faster is that the evidence disproves flatness in the manner you're talking about.
That's closer to what I said, and it is correct, for a sufficiently small region like the one I mentioned.
Doesn't mean your claim is correct, things don't accelerate when projected upwards, be it over a millimetre or a mile.
I can do the calculation using SR
I asked you to show it. You haven't. I'll give you another chance to provide it before I simply conclude you're a liar.
and get the same result as a physical experiment involving gravity, like those done in high school.
I'm not arguing with you invoking the equivalence principle, I specifically said I know its applications to GR.
That trumps any purported invalidity you can come up with.
My disagreement is with your claim things accelerate upwards, not downwards, when projected upwards. You have yet to say anything to justify that. Please pay attention to what I'm actually saying, I know its difficult given you don't actually know any physics, particularly relativity, but at least
try.
Nowhere did I say that SR alone can be used for vast distances involving gravity.
Then why are you talking about it? All you've done is say the equivalence principle, which you already knew before your dream because you've read books on relativity. I'm asking you to justify things which you disagree with the mainstream on, like the claim I just mentioned.
We don't know everything about it. Namely, we don't know (and haven't tested) that an object launched upward at a speed close to the speed of light accelerates away as we measure.
Why would close to light speed make any difference? Are you saying the direction gravity works in is dependent on the motion of the object its acting upon? You need to justify that if so. All projectile experiments disagree and while none have been done involving objects moving close to the speed of light there are experiments done involving light and it behaves in the way expected, not as your claim would imply. You can't change the speed of a photon but gravity will red or blue shift its frequency. Red shifting is the photon equivalent of slowing down for a massive object. The Pound Rebka experiment saw photons redshift when fired upwards over a distance of a few dozen metres.
You claim you have the equations but you can't provide it. You don't have any experimental evidence either, you're having to ignore things you don't get right and as a result you're just changing your story. Every experiment disagrees with the notion of things speeding up when fired upwards and so you're having to make your claims only about things we haven't done experiments on. If you can show the derivation of this result in relativity then I'd love to see it, it would validate your claim. If you can't provide them then you're just making stuff up about something you know you can't be checked on.
My "admission" wasn't that. An example of your giant assumptions.
You sad "
I don't have a formal background in physics but I have read some books on the basic ideas, enough to mostly follow what he said.". I took that to mean you've read pop science books. If I'm wrong about this please explain precisely what you have read and know about relativity so as I know what level to pitch my explanations. I assumed low because anyone who gets his physics knowledge from dreams is not putting themselves in a position which makes them seem rational and informed.
I'll do this, but not for you, which clearly that would be a waste of my time. I'll do it for any other polite poster who asks for it here. The experiment is obvious. What I'll do is show that SR predicts acceleration away.
Are you a sock puppet for Jack_ or is it just a coincident he goes and now a new nut who makes claims he can't back up in relation to relativity turns up?
You came here and started this thread and it would be logical you want to get your claims/ideas to the attention of people who can evaluate it in an informed manner. Now you've had an informed person give you his opinion which isn't just a pat on the back you don't want to play any more.
People post their 'work' on line for generally one of two reasons. Either they don't believe their work, having just made it up, and just want to be thought of as clever and get attention or they honestly believe they have something which could contribute to physics. If you're the former then you're a troll. If you're the latter then it would mean you want your work to come to the attention of academics and physics researchers and so you surely would expect at some point to be evaluated by such people. If you can't justify your claims to a single postgrad on a forum what makes you think you'll have an easier time with journal reviews by professors? You have to be prepared to justify claims and retort criticism, as that's what peer review is about. Everyone in academia has had to correct their work at some point due to peer review, why should you be different? I ask you to justify your claims in a manner expected of anyone who knows relativity or hopes to get his work to the attention of the mainstream community and now you're disgruntled? You should have expected you'd be asked further questions!
And if you think I'm rude then you've never been to as conference. I've seen people giving talks to hundreds of researchers be told "You're wrong, this is terrible and stupid because of X, Y and Z", people storm out in disgust or to be ripped to shreds in front of all their fellow researchers by one person who isn't going to take any shit from someone making unjustified claims.
A good physics result (or any in science) stands up on its own merit. If you think I'm rude then post retorts to every one of my criticisms, prove I'm wrong about you. Ignoring me doesn't retort them. Ignoring a journal reviewer's comments will mean you won't get published. People didn't like Einstein's work but it stood for itself. Einstein didn't like quantum mechanics but it stood up for itself. I'm being rude to
you because if you're honest and have the results you claim you'd be able to meet the basic standards expected in science but you aren't so it seems your attitude/behaviour is dishonest. You justify your claims then I'll admit I'm wrong. You being rude to me wouldn't bother me in the slightest as I am not making claims about my work.
Nah, it comes right from the physics books. So does relative expansion. I can give examples if you ask nicely.
I've asked several times and if you are honest you'd provide justification for your claims. The fact you're dancing around justifying your claims demonstrates you're not honest, you came here simply to preach your pet theory. If you had actual results you'd have provided them immediately. And it doesn't come 'right from the physics books'. If I'm wrong provide a reference to such a book (including the page or chapter number).
I'm only going to show that SR predicts that an object thrown upward at close to the speed of light accelerates away as measured from the ground. (To be clear, by "accelerate away" I mean that its change in distance per unit time increases.) The experiment is obvious from that.
Now I'm thinking you're MacM or whoever it was because I now realise what you're actually going to do, that you've been playing silly word games and I'll say it out loud for anyone else.
From the point of view of the
ground the projectile decelerates as expected. Its less simple for the point of view of the
projectile. Initially it sees the Earth as a squashed sphere due to length contraction but since slowing down means less length contraction, it sees the Earth get fatter and the corresponding distance between it and the Earth increase, on top of the distance increase due to its relative motion. Hence it might seem that from the projectile's point of view its accelerating. This is an argument MacM used in previous threads.
Your point of view is wrong, you have failed to calculate worldlines, you're instead relying on your physical intuition which is false. You've taken a result about how GR reduces to SR instantaneously at a given space-time point and then tried to extend it, using your intuition, to more complicated cases and thus you've gotten it wrong. If you do the calculation properly using the Schwarzchild metric to calculate the times and distances measured by objects moving along geodesics (as any projectile will) you'll find there's no contradiction. This is the difference between t and $$\tau$$. Instantaneously at a point you can pick coordinates such that $$t=\tau$$ but irrespective of how small a region you consider motion for a non-zero amount of time. Under the gravitational influence the object's velocity changes and length contraction is changed
BUT so is time. This is seen in the Schwarzchild metric where $$g_{tt} = \frac{1}{g_{rr}} = 1-\frac{GM}{r}$$. When you calculate how much distance the object believes itself to have moved over what time you'll find there's no contradiction of the sort you're claiming.
When you do the full GR calculation you get a consistent result. You are obviously unaware of this and I'd wager you can't actually do any GR and that's why you're making such a fuss about simplifying to SR so you can use the good old $$\gamma$$ factor. Cranks can just about handle $$t' = \frac{t}{\gamma}$$ and $$L' = \frac{L}{\gamma}$$ equations and I suspect you're the same. As a result you have to convince yourself you're able to reduce the system to SR else you're unable to justify your claim.
If I'm wrong about this show you can do the full GR case. That way we can all be sure you do know what you're talking about and any approximation introduced by using SR isn't an issue. Solve the geodesic equations for the Schwarzchild metric and consider a projectile with initial velocity $$v = \partial_{r}$$.
And given I'm certain you're unaware of it, the examination of radial motion for projectile motions in GR via geodesics is standard homework on any GR course and has real world applications in GPS systems as they aren't in perfectly circular orbits and their ability to very very accurately measure distances via light timings is essential for the system to work. You are, once again, contradicted by experiment.
Also you need not have considered GR since the manner in which the projectile has a force applied to it is immaterial, you're only considering its position and motion relative to some given observer located in space. Then you can use SR but you get the same result, no contradiction. Two objects moving apart, becoming relatively stationary and then doing distance and time measurements are bog standard homeworks. Look at the threads started by Jack_ (if you aren't him that is), he tries to invalid SR using such systems (but a different particular effect/result in those systems) and its explained to him many times these are all common homework problems, they aren't new or unknown. They have been worked through and known to be consistent and experimentally accurate. And you, like him, are trying to make an argument from ignorance.
real ones. I'd give you examples from the interweb.
