Strange

I'm not sure why. That describes the earliest period of the big bang, and I thought you were more concerned with recent expansion.

Yes. I think that very close to the source, the waves may not be completely isotropic but as soon as you get a reasonable distance away, the waves are the same in all directions. (note that there are components that fall off at different rates with distance)

The "medium" is space and time itself. I do wonder (and I really don't know) if some parameter(s) in the Einstein Field Equations can be interpreted as something analogous to "stiffness" or "density", or something else that would define the speed at which waves travel. Similar to how the vacuum permittivity and permeability define the speed of light.

Your argument seems to be that new words or sentences cannot be created because there are an infinite number of meaningless combinations of letters. Therefore this discussion cannot be taking place. As you say, all we are able to do is shuffle letters around not create new words "de novo". So we must all be speaking the same language created after the fall of the tower of Babel.

Why? Whenever people explain your mistakes you either ignore them or insist that you are right and the rest of the world is wrong (as in this thread). It is a waste of time trying to help you.

Obviously not because you get the wrong answer.

So you failed your exams but think you should be able to do whatever you want anyway. Meh.

And, as far as I can tell, you have learned nothing. Presumably, you refuse to learn because you have already made your mind up (even though you don't understand the current model). Instead, you go out of your way to invent "errors" based on your lack of knowledge.

Why? What about non-insect parasites?

The CMB is very nearly the same in all directions around us. As is the rate at which galaxies are moving away from us. This makes it look like we are in the centre of the universe. But actually, we are just in the centre of our observable universe. A little thought shows that all galaxies are moving away from each other with a speed proportional to their distance, which means there is some sort of uniform expansion or scaling going on (just as predicted by general relativity). The thing about the CMB is that it is an almost perfect black body spectrum (and so it can't be, for example, just the light from distant stars) and it has exactly the temperature predicted by the big bang model. Basically, the big bang model made a number of predictions all of which have, so far, been found to be correct. That is why it is the current best theory we have for the nature and evolution of the universe. Not at all. It is great that you are interested and willing to test your ideas.

There was another thread recently where someone tried to argue for falling in creating the impression of things moving apart. I see several problems with this: 1. There is no centre (in current cosmological models). Or, if you prefer, the centre is everywhere. 2. I don't think that the increasing separation between free-falling bodies is proportional to distance. I can't be bothered to do the math to disprove this, and the other person couldn't do the math to prove it. Can you? 3. If you consider multiple objects falling towards a common centre from the same heigh, then they will be on radial paths and so will get closer together. This is not what we see: we see isitropic expansion; not expansion in some directions and contraction at right angles. 4. How long could we continue falling until we hit the [nonexistent] centre. 5. How does this model explain the spectrum and temperature of the CMB? 6. Oh, you know. All the other evidence for the big bang model. And the fact that GR works, etc.

You are very fond of accusing others of logical and rhetorical fallacies so I will just point out (again) that this is a strawman argument. NO ONE claims that genes magically appear from nowhere (i.e. de novo). However, new genes can be created by a various mechanisms (some of which you admit to) and these can then change to perform novel functions.

Which you have spectacularly failed to do. Odd. I have seen several. I assume yours is a [quasi] religious belief that is impervious to logic or evidence (such as the fact we see evolution happening - including the creation of new genes - so it can't be impossible).

Firstly, congratulations on being imaginative and interested in the subject. But it isn't accurate to describe a black hole as a "rip" in space-time. It causes the same sort of curvature as any other massive object, just more extreme. Also, the expansion of the universe is not like an explosion. That implies that everything expanded from some central point out into empty space. In the standard big bang model there is no centre and space was always full of matter. It has just got less dense and cooler over time. Finally, if we (and presumably everything else) were being pulled towards a central black hole then things would appear to be getting closer together not furtehr apart. So, your idea doesn't really work. I suggest you read up a bit more on the current big bang model.

Something we can all agree on. You just have to remember to say this to yourself before posting in future.

There is a process called "science" where people develop "theories" based on what we observer. These theories use mathematics to make predictions that can be tested by experiment. Sometimes the experiment shows those predictions to be wrong and we need a better theory. Sometimes, as with gravitational waves, the experiment matches the prediction fantastically well. For one thing, a truck falling off a cliff would not reproduce the precise signal created by two black holes of a specific size merging. For another, perhaps you should read about how LIGO works and the many different measures they have taken to eliminate signals like this. For one thing they do things reduce the effect on the instrument (such as having a 40 kg mirror suspended by glass fibres). Then they measure other signals and subtract them - they have many other detectors outside LIGO which will detect any local effects so they can be eliminated from the experimental results. Except it has been. I am sad to hear you say this. The argument that "you can't do it in the lab so it isn't real" is usually used by anti-science types such as creationists and those who don't like in the big bang theory. There are a great many things we can't reproduce in the lab: from plate tectonics to stars. That doesn't mean we can't do experiments. Personally, I find it much harder to build a mental model of that concept. I don't have any "intuitive" idea of how virtual particles mediate forces. Whereas the changing geometry of space-time is kind-of obvious (perhaps because it has been around, and talked about, for longer than I have been alive). swansont has just calculated the scales involved but you think you can compare this with a lead lump swinging on a rock. I wonder if you think about what people write.

You might find it less frustrating if you learned some science instead of assuming that you are always correct and sciences is therefore wrong. (Everyone else would find this less frustrating as well.) Your misunderstandings about this (and every other) topic have been explained repeatedly. Only for you to come back with exactly the same arguments. It is a waste of everyone's time (including yours).

Laser cooling has been used for a long time. http://hyperphysics.phy-astr.gsu.edu/hbase/optmod/lascool.html

No. We don't have the technology to move sufficiently large masses around (or, equivalently, we don't have the technology to detect waves caused by moving small masses around).

Yes, space is full of stuff from photons and neutrinos, through gas and dust, up to planets and stars. None of which is relevant. Gravitational waves happily ignore all that. They would travel through completely empty space equally well. Well, if you can't accept it, I suppose that is just too bad. There is nothing anyone can do about that. But it is a shame because you are rejecting and missing out on a fascinating area of science.

If you want to, you can divide space into a grid and measure movement against that. You can imagine a mesh of wires, if you like. As the gravitational wave passes it will stretch and squish the grid. The fact there is nothing there isn't really relevant. (It isn't really true, either. There is always something: gas, dust, stars ...) The Ordnance Survey's grid references still work over a body of featureless water or sand. As distortions in the geometry of space time. Space-time is not still. Distances, angles, ... in other words: geometry.

Which only reflects your own [lack of] understanding.

Hmmm... if only there were some way of selecting from that space.

Citation needed. Citation needed. Has it never occurred to you that the problem might be that you don't understand? After all, you make that very clear to everybody else.

They were 665 million light years away (ignoring any expansion of space that might have occurred in that time). That is a distance. That is one of the three spatial dimensions that make up space-time. Those are the same dimensions that get curved by mass. It is regular changes in those dimensions that make up gravitational waves. If you want to call space-time a "medium" then please do. Einstein himself referred to it that way on at least one occasion. But he also stressed that this "medium" is not material; it has no measurable properties. Passing through the intervening distance (or space). One of the dimensions of space time, etc. etc. Depends which philosopher you ask. But as it isn't relevant to the thread, I am going to ignore it. In this case, it came from the mass of the black holes. Mass approximately equal to three times the mass of our sun was converted to the energy of the gravitational waves. And since then it has been spreading out through space. A tiny fraction of it was picked up by the LIGO detector. Space-time.