geordief

Is there any purely linguistic merit in (for discussions involving the universe) the use of the present tense was actually outlawed (except for subjective purposes such as "I am right" ) since, as Studiot says all events occur in the past? So , for example the sun is not 8 light minutes away it was whatever it was 8 minutes ago.

Is there any upper limit on the ratio of the size of the unobservable universe to that of the observable universe? Would there be any theoretical consequences if it was infinite? Can the size of this infinitely sized overall body have an origin which is infinitely small or it this "point smaller than the atom" some kind of a lower limit for the "origin"?

Yes ,it has the feel of a very half baked question now. If mass is somehow conferred on matter by this Higgs field and we have the problem of Dark Matter too then it seems a pointless question after all. One definition of a Universal centre of mass might be the direction in which all matter is converging but no one has any idea whether this might ever happen,have they ?(we have to stop expanding first and then we can compare notes )

Can this exist?I have been told that it does but I cannot seem to find any old posts lying around the internet that support this idea. Anyone here want to have a go at the question (it is understood that there is no centre ,I am asking whether there is a centre of mass ,although it could not be used as special Frame of Reference)

Another superb example of observation is Temple Grandin (I caught the docu on BBC a few days back..) and her "huge box". . unbelievable but true https://en.wikipedia.org/wiki/Temple_Grandin Yes observation really is a praiseworthy skill and aptitude.

That is a bit of a surprise to me. You mean these candidate theories can be developed without mathematical underpinning and then wait for mathematics to catch up? What kind of methods are used when mathematics can not be used ? Strange that someone as poor at maths (and deductive skills) as I am should be asking this question.Can maths be seen as the skeleton within the flesh of creative reasoning?

Are there any promising new approaches being explored at the present time? Are there fundamental aspects a hoped for theory where it is confidently expected that elements of General Relativity and elements of Quantum Theories broadly overlap? Would Fields be one of them? Should the application of Special Relativity inside the atom be counted as a step along the path to a theory of Quantum Gravity (didn't Relativity start out as "Special" and progress to "General"?

I assumed it was an innocent mistake....If it wasn't they got us...

fake jokes

But not as spooky as the real thing ( spøk means joke in Norwegian btw)

I missed that**, but if GR is accepted as incomplete is expansion within its remit?Would a theory of quantum gravity eventually have more to say on expansion (or am I thinking of inflation?) **will look.

Is there any way it can be shown from basic principles that global expansion must ** occur in the absence of gravity and that the alternative where expansion or contraction do not occur is completely unfeasible ? In other words is the only surprising thing about expansion that the centre is apparently everywhere ?(and this as a result of the universe being practically point like in the past) Was this point like origin thought perhaps to be a field like object of some kind ? **ie aside from observational evidence.(was the whole idea of a static universe always a non starter and simply entertained for lack of real thought on the matter at the time?)

Would it be possible to give an example of how relativistic effects would be evident without having recourse to the properties of em radiation? Can the gamma factor be arrived at through other means?

Causality seems to me far more fundamental than any speed.Once you accept a universal principle of causality (so breaking it is not a consideration) does everything not just get into line? From causality being fundamental we must have a maximum speed of transfer of information and from maximum transfer of information we have a maximum speed of information carriers(objects with or without mass) It just so happens that c is the fastest speed clocked and so it is probably also the fastest speed possible. Perhaps I am being simplistic? It is not the speed of light that has a bearing on causality but the other way round.

I have posted here before in the Homework section when I feel my question is very elementary and hope I can "do it again....... So... if we preclude relative motion between objects from the scenario could the geometry of spacetime be described as Euclidean **? So ,if objects are (can they be? Is there any point ?) treated as static vis a vis one another can they be modeled consistently in a Euclidean way or does one still have to take into account the different distances between objects? **by "Euclidean" I mean the geometry I learned at school;we never called it "Euclidean" ,it was just "geometry"

You earlier today(?) said that things (inc gravity?) were fundamentally quantum rather than classical. Does this hierarchy also apply to the "boundary of a boundary "? ie it applies if it does in a classical context and so cannot be considered fundamental? Ps I don't want to give the impression that I was able to understand the "boundary of a boundary" idea which you tried to help me with in an earlier thread elsewhere a good while previously(although I feel I may have appreciated its importance)

Nicely said.

Reminds me a bit of an old thread of mine I was looking at yesterday https://www.scienceforums.net/topic/107248-quantum-gravity/ I was wondering then whether the macro side of things might be explained purely as a statistical outcome. I was thinking along those lines perhaps as a result of very recently learning that computer translations may have have dispensed with the rules of language and simply depend on statistical correlations to produce the results they do (there was a prog about statistics on BBC4)

Just an analogy? But should I be thinking of the waves as passing through the interior of the body of water as well as on the surface?

What puzzles and worries me is that ,broadly speaking a word should be deemed acceptable for one group of people and not for others. On inspection one can see good reasons for it . . To expect a life without contradictions is to set oneself up for a fall.Lets embrace our absurdities and ,as they say not take things too seriously (this too will pass.....) Here endeth the platitudes

Our gain

This story seems pertinent. The word was used in an argument and it was claimed it carried no offensive connotation in Uruguay. https://www.theguardian.com/football/2011/dec/15/luis-suarez-patrice-evra-case A huge story at the time in this part of the world.

Yes ,a pleasant surprise to see Markus here.... I thought I had read Einstein ,as a preamble in one of his popularizing publications perhaps stating that all children knew that the speed of light was the same ...

Tree rings. They can be made to play a tune and are caused by summer/winter cycles.

What about the recent gravitational wave ....has that left a permanent mark on the equipment (or the bodies it passed through ) or has it moved on without a trace behind? Would any imprint would be greater closer to the source? I seem to remember we were invited to listen to the "sound" of the Binary Black Hole Merger at the time. OT Could Newton have predicted Black Holes?