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I haven't been around much of late, but I'm really interested in why and what this supposed political motivation is. I really can't see how any small under-estimation of confirmed exo-planets could lead to any thought/s of any political agenda.....other then of course, that the few left off their list, may also have confirmation/s of being far more then just another common garden variety exo-planet...like for instance, having a detectable oxygen atmosphere. As you rightly said earlier, the JWST will be able to give even more confirmed and accurate results re exo-planets discoveries. I actually like your thinking re space stations, but I don't agree with "never getting to taste it" remark. Given the time of course. I see it as inevitable that given the time, [that is in a time frame in excess of your space stations idea] all options and achievements will be undertaken. Generation type space ships to these suitable type exo-planets, should be viable to any civilisation that is able to undertake your space stations idea.

Bingo! As I have mentioned before, my first science forum which is now defunct, had our own Astronomer and a young professional GR expert. Both help baby sit me through many difficult to understand concepts. Delusions of grandeur, tall poppy syndrome, or some religiously inspired mission to deride science, are powerful yet delusionary reasons that drive these people. Mods have a job to do, and with the exception of one mod and administrator on another forum, I have never criticised them for the difficult and thankless job they do. My main beef with the administrator on this other forum, was the free hand given to the likes of those claiming GR is false, or some other aspect of science, the free hand given to other nuts claiming how we have been visited by Aliens, and any other number of crazy conspiracy notions, all for the sake of quantity over quality.

Clocks, measure time: Aging is a result of the accumulation or passing of time: When time is measured to be dilated in another frame, the clocks that measure it are slowed, and any aging of biological entities are also as a consequence slowed: The validity and acceptance of SR and the consequences of length contraction and time dilation are universal and agreed to by many tests every day, including GPS navigation and positioning. That small minority that hold a contrary position, are probably cranks of one sort or another and in the same nutty class as those that still believe the Earth is flat, and that it is the center of the universe.

If you are referring to the "dark side" of the Moon, there is actually no dark side. From Earth we only see slightly more then half the Moon, as the Moon's rotation period is equal to its orbital period about the Earth. We never get to see the "far side" of the Moon from Earth.

I see it more like the media hanging on his every word, and sometimes taking that "word" out of context, or creating some sensationalist aspect where there is none. eg: the false headlines a few years ago "Hawking says BHs do not exist"

Time was created at the BB. It is not a human invention. If life had not evolved, time would still pass. It is the measurement of time, (clocks) which are a human invention. And as already mentioned time dilation and length contraction have both been totally verified. When we observe time dilation, it is both mechanical and biological. The astronauts in the ISS are aging slower then us on Earth, albeit by tiny amounts.

OK, I'm getting there, (I think) slowly but inevitably. Thanks.

Yes. John Wheeler?? from memory. OK, I see the difference, personally I'm in a habit of referring to it all as spacetime. I'll consider that. I understand that, but doesn't the universe/spacetime overall have a topology that is very nearly flat? And isn't there a difference between the mass/energy density IN spacetime, [galaxies, stars planets etc] to the mass/energy density OF spacetime? [possibly the Cosmological Constant or whatever is the impetus of the DE component]? I have "faith" in your ability. Just as our local group of galaxies, due to mass/energy densities is decoupled from the overall expansion rate? And as other high mass/energy density regions of spacetime are decoupled.

You are essentially saying.... https://einstein.stanford.edu/content/relativity/a11332.html Can space exist by itself without matter or energy around? No. Experiments continue to show that there is no 'space' that stands apart from space-time itself...no arena in which matter, energy and gravity operate which is not affected by matter, energy and gravity. General relativity tells us that what we call space is just another feature of the gravitational field of the universe, so space and space-time can and do not exist apart from the matter and energy that creates the gravitational field. This is not speculation, but sound observation. ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: The highlighted part was an error which you need to omit. I e-mailed Sten Odenwald on that rather confusing bit..- I wish he would take the time to remedy though!

What do you mean by "comes to equilibrium"? Other then the compulsory collapse of the matter/energy of any object once their Schwarzchild radius is reached, [at least up to the quantum/Planck level where GR fails us] we don't know much else of what is inside the EH. Any Steady State speculative notion though is totally baseless.

Both answers that are essentially correct, although as a lay person, and answering other lay persons, I generally just say that the universal speed limit, "c" only applies to things with mass...spacetime has no mass. How many out of ten for that answer?

Yep, OK, gotcha!

Forward Time travel as per the "twin Paradox" is allowed for and theoretically possible according to relativity. Backward time travel is another matter altogether. But Kip explains it better then I. https://plus.maths.org/content/time-travel-allowed

From the point of view of an observer on a train station platform, say viewing the light clock in a moving train? Perhaps....As I said, I hope I am wrong.

The second clock is in motion and consequently more distance is covered. As the speed of light, "c" is constant, which means that time will appear longer. The speed of light is the universal constant. Perhaps I'm just an old cynic, but I see a certain pattern developing with the questioner in the OP...perhaps I'm wrong...let's see.

If you are asking why time dilation occurs, that is best answered by another Einstein fact, that being that the speed of light is the same for every observer no matter his or her frame of reference. This can be further explained by the following..... http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/Special_relativity_clocks_rods/index.html What happens when a light clock is set into rapid motion, close to the speed of light? It is easy to see without doing any sums that the light clock will be slowed down. That is, it will be slowed down in the judgment of someone who does not move with the light clock. First, we will take the simple case of a light clock whose motion is perpendicular to the rod. The light clock will function as before. But now there is an added complication. The light signal leaves one end of the rod and moves toward the other end. But since the rod is moving rapidly, the light signal must chase after the other end as it flees. As a result, the light signal requires more time to reach the other end of the rod. That means that the moving light clock ticks more slowly than one at rest. Remember the light postulate. It tells us that the light always travels at the same speed in any inertial frame of reference. That the rod along which it bounces is moving rapidly will not alter the speed of the light. Here's an animation that shows a light clock at rest and a second light clock that moves perpendicular to its rod. The light signal in the moving clock chases after the rod. To reach the other end, it covers more distance and, as a result, requires more time. Here's the same animation in larger size in case you have a big screen. If you watch the animation carefully, you will see that the moving light clock ticks at exactly half the speed of the resting clock. That is because the light signal of the moving clock has to cover twice the distance to go from one end of the rod to the other. ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: The article further explains why length contraction also takes place, and why one second always passes at one second per second, within one's own frame of reference.

Sure you have been answered, many times right here. Relativity is termed relativity simply because time is relative. Every individual in every situation will feel time pass both mechanically and biologically at one second per second. It is only when one compares his own rate of the passage of time with another, that dilation or discrepancies are noticed. At Earthly based speeds and distances though, the difference in effect is very tiny and was not noticed until Einstein came along. You can rest assured though that it is real and has been verified observationally and experimentally particularly in particle accelerators and also our GPS system..

GR has passed all tests thrown its way and continues to pass. It gives the same results as Newtonian within Newtonian limits, with far better accuracy. If you disagree my bet is that you are certainly wrong and probably have an agenda of sorts. But in reality science forums are all beset by "would be's if they could be's" that claim they have over thrown Einstein and his theory/s. You are just another number in that list. And a marshmellow hitting you at 99.9% C would pass right through you.

Science is what we know: Philosophy is what we don't know.

Or sensible Americans can give this fool a kick in the backside and oust him from power, and once again make the USA part of the solution and not against it.

Let me make a few points that at times I have made before in my time on this forum. Of course being an amateur and non scientist you can chose to treat my points with whatever contempt you think they deserve. [1] This is a science forum. [2] All incumbent scientific theories start out as speculation or hypothetical in nature. [3] As evidence builds up supporting a particular theory, and as it is successfuly making correct predictions, it grows in certainty. [4] All incumbent scientific theories are being continually put to the test everyday. [5] Any person that believes he has some alternative to an incumbent theory, needs to "run the gauntlet" just as any incumbent theory has also run the gauntlet. [6] While science forums such as this are great discussion platforms, no incumbent model will ever be invalidated on any forum, and no alternative hypothetical, will ever displace that incumbent model. [7] There is a professional proper peer review system where any possible alternative hypothetical can be examined, researched, and either dismissed or accepted. [8] Any accepted model will of course need to explain and model existing observations better then the incumbent model, and/or explain further any limitation of that incumbent model. [9] Forums such as this are in the public domain and therefor open to any and all manner of kooks, cranks, and any number of variety ailments such as "delusions of grandeur" "tall poppy syndrome" "excess baggage and agendas" including god botherers, that will do whatever is needed to further their personal anti science campaign, as in the main, science has removed their necessity for any deity or god. [10] On most occasions this conglomeration of anti science brigade will have been banned on one or more science forums elsewhere.

My apologies....I understand it even less.

Trump's only "methodology" is as we say where I come from, "F%#@ you, I'm alright Jack, mentality" I do agree that 100 years is too soon, but avoiding any catastrophic astronomical disaster, or other global threat, we will at the very least have out posts on the Moon and Mars, similar to Antarctica. Colonisation of another world and stellar travel may take the better part of a 1000 years.

Discussing the scientific method and how the universe works with someone with a "god agenda" has been shown to be fruitless

Let's get down to the nitty gritty. It's painfully obvious you are driven by an agenda, Let me mak a few points...Analogies are useful but near all have limitations....the stretched rubber sheet, the raisin loaf etc. It's also obvious to blind Freddy that the current model of gravity is correct,. If they weren't I don't believe we would have put men on the Moon, and sent probes to all planets in the solar system including the two Voyagers to two and four planets respectfully, and from my knowledge, all these space endeavours Newtonian mechanics was accurate enough and GR simply was not needed, although it would have given the same results. You see your rather silly childish claims that maths is not needed is just that and a pure cop out, the maths and observations go hand in hand and are both needed. That along with the fact that not one of your links support your speudo claims in any way, and in effect your rather tiresome unsupported religious driven agenda and rhetoric needs to be recognised for what it is.