mistermack

As far as the word exists goes, I would say that time definitely exists. It exists as a phonomenon, not as a thing. Just as motion exists. If you restrict existence to things, then you can't describe the world properly. The past doesn't exist. The future doesn't exist. But time exists as a characteristic of change. And so it's a real phenomenon.

Best to install a lift then. But spiral stairs wouldn't be too bad. A bit like climbing upstairs on a bus, as it goes round some bends. Edit: and up and down hills at the same time !!

Remarkable. There but for fortune . . . .

So, with the metric expansion of space, distances are creeping up, with time. And in a black hole, distances are shrinking. So basically, my OP was suggesting that matter and energy could be causing distances to shrink, slightly, in their immediate vicinity.

It sounds like a perpetual motion machine, producing additional energy from nothing.

So we're talking about a field that normally occupies a certain volume in remote space flowing into a black hole of relatively small volume or being annihilated? That's what I was picturing, anyway. Presumably space-time coordinates are describing something, even if it's not something in the sense of matter. I can't imagine a flow of mathematical coordinates, unrelated to anything.

Are you talking about the coordinates that describe a field?

With the river model, the idea must be that space is being annihilated, or at least compressed to near nothing, in a black hole. If a black hole is has had a river of space flowing into it for ten billion years, that's a lot of space, in a small object. The idea that the Earth could be doing the same thing, on a much smaller scale, I don't think it's all that preposterous. One thing I was wondering was what would this loss of space to stars, black holes and other matter actually do to the space that's left? Would it stretch it in some way, and if so, could it cause an apparent redshift?

I would add that if you find different levels of gravity desirable, a circular cross section could still provide that. You could simply go up a flight of stairs, to a level closer to the centre of rotation, and feel lighter. So just like on Earth, we would probably go upstairs to bed. In space stations on a gigantic scale, you could maybe go upstairs to lower gravity levels as you get older, or if you're not well.

I have to say I'm quite disappointed that nobody on this site has torn into the basic premise of this thread and refuted it. I'm still trying to refute it myself, and would have welcomed some input. The thoughts that I've had about it recently are based around the fundamental question, of 'can space move?', as I postulated. It's certainly modelled as moving, in the published river model, so I have my doubts if there is a simple refutation available to the concept of a flow of space. Otherwise, the physics world would have refuted the river model. As I understand it, a flow of space in that model is a valid interpretation for curved space time. The basic idea, that small amounts of space are constantly being "gobbled up" by massive matter and energy might seem to be counter intuitive at first sight. But the more I've read, the less constant and unchanging space becomes. You have the idea of inflation, which is fundamental to the big bang model. Space is definitely changing at an incredible rate on a gigantic scale. Then you have the idea of the metric expansion of space, which is supposed to be happening constantly, everywhere, all around us. If space can expand everywhere, 24/7 spontaneously without any known cause, then surely it can be absorbed, or shrink, or be annihilated on a small scale in the vicinity of massive particles? It doesn't seem to be a ludicrous possibility, bearing in mind the energies involved at that tiny scale. And if it can, and did, then the process that I postulated in the OP pretty well follows on as an inevitable result, and explains the action of gravity.

As far as leaks go, it's the likelihood of a leak to the environment that's important. If there is no prospect of a breach of the outer building, then it's not much of a risk. Compare it to the Japanese accident, or Chernobyl or Three Mile Island. At present, there is a theoretical risk of very nasty accidents at the standard fission power stations. But we take the risk, and manage it, and make it as small as possible. It looks to me like the basic risks are lower in a molten salt reactor, and can be designed to be much lower, with some designs. The worst that can happen is probably a big earthquake, or a direct bomb hit, and I think those things can be covered in the design. I haven't read of any materials problems that are considered a stumbling block. I think the experimental reactor threw up very few serious problems in that regard. If you looked at modern nuclear power stations in terms of the problems and risks, you could produce a pretty formidable list, and a strong case for never going down that road. But once you've started, you can end up with a practical power station that has a place in modern generation.

From what I've seen, helium3 would require far higher energies to fuse. As controlling a plasma is currently only possible for a few seconds, and projected for the ITER reactor for runs of only 15 to 20 minutes, at far far lower energy levels, there isn't a lot of point in going down the helium3 route any time soon. The technology just isn't there, and it doesn't look like it will be there for a very long time, if ever. The molten salt reactor is bit of a mystery. I've not read of any serious problems with the concept, and don't really understand why it hasn't been developed to commercial levels. It seems to have a long list of advantages, and very short list of snags. Anybody know more about it?

That's been true up to now, but it's not the whole story. The ITER reactor being built at the moment is designed to produce more than it uses by a large factor of about 10. And in any case, the energy that you put in doesn't have to go to waste. Say you put in X amount of energy, and it produces 0.5X of extra energy, then you finish up with 1.5X of energy, for each X of input. If you can make the most of that 1.5X of energy, then it's not so bad. The problem is, you put in expensive energy like electricity, and get out lower grade energy like heat. That's why you need a good ratio of power out to power in. But if you could use nearly all of the heat produced for productive projects, after it has generated electrical power, then the economics would be far more favourable. Low grade heat could be used in greenhouses in cold countries, and to heat cities. Maybe they could use it in hot countries to purify water. Anyway, it will come, it's just annoying that it's taking so long.

From the smattering that I've read, the control of the plasma isn't the greatest problem for the future. It's finding materials that can withstand the neutrons long enough to enable a steady burn over a period that will make electrical generation a practical proposition. The heat needs to be transferred to water to make steam for a turbine, and the water needs to be contained etc. So it's the materials problem that casts a shadow over the future, it is what is the big uncertainty. Will the problems be insurmountable? Will they cause too much cost? That's where I believe the future headaches lie. You need the reactor to be up and running before you can really put the materials to the ultimate test.

Isn't it a fact that the energy generated is not "free" because there is an increase in entropy? Free energy in this sense would be useful energy that came at no increase in entropy, which can't happen. You can't keep producing useful energy in the process indefinitely. So as others have said, you are just extracting energy from a store.

Too difficult. (for me). This is as far as I got : Modelling the situation as an intake, submerged in a sea, I wanted to work out the acceleration of any particle of the fluid, in relation to it's distance r in metres from the intake. Fixed flow rate down the pipe f = Volume V cu metres/T seconds f = V/T Take two concentric spheres at radius r, inner(ri) and outer (ro). Outer sphere has area Ao, inner has area Ai. Flow speed at outer = f/Ao Flow at inner = f/Ai So increase in velocity is f/Ai - f/Ao. = f(Ao-Ai)/AiAo The area of the spheres is proportional to the radius squared. ie 4πro² and 4πri². So the increase in velocity is f(4πro²-4πri²)/(4πri²)(4πro²) = f(4πro²-4πri²)/16π²ri²ro² So the increase in velocity divided by the time T is f(4πro²-4πri²)/16π²ri²ro²T metres per sec per second. Which gives the acceleration for an elapsed period of T seconds. (In the unlikely event that something isn't wrong with the calculation.) How you get from that to acceleration at any individual point, as T tends to zero, requires calculus I believe, and that's a complete void in my memory. I did actually use maths at university, so I did once know some of it, fifty years ago, although there's no sign of it now. True. But this was suggested as an alternative way of looking at mainstream science, not a replacement for it. If there was a contradiction to GR inherent in it, I would think that that would refute it. There are lots of things suggested in the physics forum that are not mainstream science, but equally don't contradict it. The River Model seems to fall into that category too. It's been published, been used, doesn't contradict established science, but you wouldn't call it mainstream. (or maybe you would?) On the time dilation calculation, thanks for that. I suspected that that was the case, but couldn't prove it, as my maths has been going stale for fifty years now. But doesn't it seem too much of a coincidence, that gravitational time dilation, and the hypothetical time dilation that would be caused by space falling into the large body as postulated, are identical? Is it more likely that there are two unconnected types of time dilation, which just happen to produce the identical quantity? Or that there is just one type of time dilation, due to motion through space? Both apparently match the facts, but wouldn't Occam's Razor favour the simpler of the two?

The girl could have been lying, and pushing on the ouija board. Any time I've taken part, someone's been pushing. (or pulling). Apart from the times that nothing was spelt out. So the work was not destroyed, they knew it existed, they looked for it, and found it. That's not evidence of life after death.

To be fair to this thread, it's been here for two weeks, asking to be refuted, but nobody's refuted it. So I think it should go back to physics, if it's not refutable.

I find the picture of a cliff edge one of the best for visualising gravity, as you often take it for granted, when just standing or sitting on level ground. A cliff edge sort of forces you to be aware that gravity is with you 24/7 and the only thing stopping you falling very quickly is the force exerted by the Earth beneath your feet. My understanding of general relativity is that if you step off the cliff, you then follow the path of a non-accelerating inertial frame, through curved space time. And of course we know that that path takes yoou straight down, accelerating at 9.81 m/s² relative to the cliff. If you stretch out your hand and touch the cliff, it will be immediately obvious that ONE of you is accelerating. If it’s not you, then it has to be the cliff. Which sounds very weird, but actually, the cliff is the one that is experiencing a force from below, whereas you are not experiencing any force, according to GR. But how could a cliff in the UK be accelerating upwards, and a cliff in New Zealand be also accelerating, at the same rate, but in the opposite direction? It would seem impossible, without the Earth being rapidly stretched out of shape. But in this proposed scenario, it does seem actually possible.

I'm not a mathematician, as I've said several times. I've shown how I arrived at what I've posted, hopefully without any ambiguity, so that people can challenge what I've said. I'm surprised that this idea wasn't ripped to shreds in the first hour, that's what I was expecting to happen. It's more than a week now. I'm not sure that my original reason for discarding it (whatever it was) was valid, but there must be plenty wrong with it, or it would have been proposed before.

Using online calculators, I’ve compared the time dilation at the Earth’s surface due to gravity with that due to the notional time dilation due to a speed relative to space of 11.186 km/sec. If they had been radically different, I think it would have positively refuted the idea. They come to 1.0000000006600 and 1.0000000006961 respectively. Given that the 11.186 km/sec figure for the Earth’s escape velocity is obviously not accurate to a large number of decimal places, it looks like gravitational time dilation is coming out the same as what the velocity-caused dilation would be. I can’t give my workings because I used an online calculator and figures that NASA give. But here are the links, if anyone wants to do their own check : http://keisan.casio.com/exec/system/1224059993 and http://www.relativitycalculator.com/pdfs/NASA_Time_Dilation_Earth.pdf Is it too much of a coincidence, that the known time dilation at the Earth’s surface is coming out the same as what would be caused by the velocity of space flowing by us, if this proposal was correct?

I've thought of one difference this process would produce, compared to general relativity. Unfortunately, it would probably be impossible to measure. If this were actually happening, then the time dilation at the centre of the Earth would be LESS than at the surface, because there would be no flow of space due to gravity at that point. Using GR, the dilation would be greater as you descend because you are going deeper in the gravitational well. Although it would be complicated, as the pull would reduce, as the amount of matter above you increases. But clocks would still run slower at the centre. With this process, they would run faster than at the surface. When I was first chewing over this idea, it was the similarity between acceleration and gravity that was nagging at me. Why would they be so similar? When you open the throttle of a powerful bike, you immediately feel a new "gravity" pulling your body backwards. Yet there is one big problem staring at you, if you try to picture the two phenomena being the same. And that is the speed of light. I have a force of about 80kg pushing at my feet 24/7. I'm obviously not going anywhere, so how can this be due to acceleration? Ok, so introduce the idea of space accelerating past me into the Earth. Now I could be accelerating, relative to space. BUT, if I keep accelerating at 9.81 m/s², I worked it out that I would hit the speed of light in less than a year. (353 days and 20 hrs to nearest hour, if you're interested.) So in less than a year, I would have broken the speed of light, relative to the space passing me by. So how can you constantly accelerate, and yet not go any faster? And that's what's answered by the funneling of space into a smaller and smaller sphere. There HAS to be a constant acceleration, at any point in the gravitational well, as it decreases in volume.

Just found a pdf full version of the river model study with the illustrations, it can be viewed and downloaded here : https://ia801009.us.archive.org/6/items/arxiv-gr-qc0411060/gr-qc0411060.pdf

To put it into perspective, if space WAS accelerating towards the Earth at the same rate that gravity causes things to drop, then the speed that it's passing us by, on the surface, has to equal the escape velocity of the Earth, as it's the same thing in reverse. That means that we would be in a flow of space of about 11.186 km/s going vertically down. That compares to about 0.5 km/s rotation at the equator, and about 30 km/s around the Sun. Then the Sun goes round the Milky Way at 220 km/s . The nearest thing in the Universe to a special, or universal reference frame, is the cosmic microwave background, which permeates the entire Universe, and they recently got a fix on that. We are moving at 390 km/s relative to that. Also, the galaxies in our neighborhood are also moving at a speed of nearly 1,000 kilometers per second towards something called the Great Attractor which is an area of space with a lot of gravity. So the 11.186 km/s figure for this idea is pretty small in comparison to what we know is happening to us on a grand scale.

Yes, it seems to be all over the web at various locations, so it seems to still have some popularity. It's occurred to me that the hypothetical velocity for the flow of space at the Earth's surface would be equal to Earth's escape velocity of about 11.186 km/s, so you could use the the resulting time dilation that that would cause, and compare it to the figure for gravitational time dilation at the surface, to see if they were the same. If they were significantly different, I think that would be a problem for the notion. Not being very mathematical though, I would struggle with that.