geordief

Yes I probably misunderstood you because I do find that whole area difficult to understand.. I have heard that "time doesn't exist " statement before . If I was to attempt to describe my reaction to it (account taken of my lack of research into the area ) I would probably start by saying that time requires a measurement and without that possibility it is meaningless to talk about time. I don't know if that makes sense or is useful but it may be the best I can do....

The question (unanswerable I think ) may be of less consequence than the question as to how we could go about learning what was actually happening then. If it is just a question of how close we can get to that moment then that is simply a quantitative improvement in our knowledge. Is it possible that our scientific civilization could exist for millions of years and not come up with any answer or even a reasonable guess or could it be that someone will have a guess and it will make sense. I mean is it possible that the scientific method will fail but that serendipity will pull us through ? (thanks Bob )

Or even a twirl. https://www.cadbury.ie/products/twirl-2364?p=2364

A suspicion I have is that Trump is such an ugly duckling that he justifies his existence by approval he can get from the victims in his entourage. Is this need for adulation something that can be rooted out of the political system ? I remember Thatcher was regarded as someone who was not liked but was respected.(not liked by me to be sure)

Damn right but canaries in coal mines were useful . 40 % is disappointing but should we have known that ahead of time ? Do we know it now? Does democracy need education to work? If we dodge the Trump bullet how can we ensure there is no repeat?

Has the waving/motion reduced over time? Are there dampening electro-magnetic forces within the fabric and between the fabric and the pole ? Would the moons gravity also act as a dampener?

Either in or out. If outside the station we can just watch to see how long it vibrates before the vibrations subside . If inside then the skin of the station plays the role of the membrane of a drum. It seems clear to me that any atmosphere would act as a dampener to vibrations on the membrane of a drum or the skin of a spacecraft (if the crew were either having a party or playing a loud note) Just because we cannot hear a sound in space surely does not mean that we cannot set a musical (or otherwise vibrating) instrument to oscillate. I only asked because I had never heard about the exact circumstance but it does not seem a bit controversial to me. On the other hand you seem prepared to believe that a carpet shaken in space cannot be made to make a wave.. That seems an extremely unlikely outcome to me but maybe I am wrong...

What happens if you bang a drum in space? Does it vibrate much longer on account of there being no atmosphere to carry away the "sound"?

The medium is the tedium ? (but I like that idea) I don't suppose there is a chance that spacetime can be seen as a field? Or that a field can exhibit curvature?

plus one for Einstein

How about this.? Space-time is a mathematical model (and is real as such but perhaps subjectively -or collectively** subjectively- real) ). But Spacetime is also a name that we give to the thing that we think the forenamed model describes (this is also "real"- perhaps objectively real) So there are two spacetimes which share the same name but they should have different names. Approaching it from another angle or aspect, we have the measurer (the spacetime model) and the measured (the "reality" it is attempting to model) Now the measurer and the measured may be a symbiotic collective entity and so each is as real as the other and neither can stand on its own. ** I am imagining a group who broadly agree upon a scientific consensus. By the way ,is it entirely apparent that we cannot hit spacetime with a hammer (a very big one) ? Did the BBH achieve that ? (did it "shiver our timbers" as its waves passed through our bodies?)

I wonder how I got that impression.Under what circumstances does an accelerometer read 100% zero.? At infinity?

My idea was that movements such as moonquakes might be used by a Moon inhabitant as a "natural" accelerometer. If the Moon was simply freefalling into the Earth (so not orbiting) and not accelerating these would not be occurring. That is what I was trying to say.in that post As I seem to put my foot in it every second post I may well be wrong but that is why I said it. I had not considered movement away from the Earth but it does also seem relevant and shows acceleration as well.

So the Moon is accelerating wrt the Earth? And you can verify this by the tidal forces on its surface (and interior)?

Hmm.So the moon is accelerating in our FOR but not in its own? thanks to everyone for all the corrections

So why do we get the twin paradox ? That has nothing to do with acceleration? I don't see where gravitation comes into it. It is simply due to different rates of speed? I am trying to work my way through this interesting but very hard document at the moment. It probably explains my OP https://en.wikisource.org/wiki/Dialog_about_Objections_against_the_Theory_of_Relativity

Right and so a clock on the moon keeps the same time as one on the Earth because the Moon is freefalling into the Earth whereas a satellite is being accelerated to prevent it freefalling and so is time dilated? Edit: in post#2 imatfaal said that the moon is accelerating around the Earth . Is that true if it is freefalling?

No , I am not sure either. Time dilation (orbiting systems) occurs without acceleration. Does it also occur with acceleration (rocket propulsion) and if so is it a different process? Ooops , I see I have not taken into account the fact that the moon must be approaching the Earth in freefall over an extended period . I need to get my thoughts in order once more

In spacetime terms the moon is supposed to be following a straight line .Is there a way we can usefully define acceleration **(differently?) to mean that a body does not follow this straight (geodesic) straight line? Will the body then lose mass? **so not acceleration but perhaps a related concept

Thanks. Yes the rocket idea was what set me off... I will have to give it some more thought

Suppose we have a body that is accelerated from point A to point B (and ,why not decelerated ,reaccellerated and returned to point A although this may not be necessary) My understanding is that the body as a whole will lose mass in order to maintain the acceleration and eventually if the acceleration is continued there will eventually be nothing left. I am wondering as to how this loss of mass is distributed through the body. Is is evenly distributed so long as every part of the body is accelerated? So ,if there is a timekeeping device on the body does this timekeeping device similarly lose mass and fade away to nothingness eventually?

I thought I had come across the idea that the electrical wave and the magnetic wave (or fields?) "piggy backed" each other and that this allowed them to move across a vacuum. Is that what disarray is thinking of and was my description accurate?

That rings true in the current political climate *shudder* Of course we are all mix and match in that regard to a degree,I guess.

I would have thought Trump in particular was pretty easy to fathom without the need for "expert" evaluation http://www.bbc.com/news/election-us-2016-36935175 Anyone still unsure may need to take the test themselves.

What? Well I suppose that is better than Macdonalds. http://scienceblogs.com/cognitivedaily/2007/09/20/more-evidence-that-everyone-ha/ I can relate to that ,even though I would be on the "minimallly significant" end of the scale.