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zapatos -- thanks for that clarification.

Look at the shell theorem - in both Newtonian gravity and general relativity. In fact, Newtonian gravity is enough as this comes as a limit of general relativity. Provided you are outside of a spherically symmetric distribution of matter, the gravitational field is exactly the same as if that mass were concentrated at the centre of the body. So, yes, as the Earth is much lighter than the Sun if you 'blew up' the Earth so that it was the same size as the Sun the force of gravity on a test mass at a given radius from the centre (r > radius of Sun) will be less than it would be for the Sun. (I hope that makes sense!) The converse statement follows in the same way if you were to shrink the Sun.

What evidence? If true, then this is irrelevant to any discussion about science. Simon - what is it you really what here? If you want to discuss your ideas on cellular automation, then please use the thread you started on this subject (but made little contribution to). Also, it is against the rules to use this forum for advertising as you have done. Please stop.

That is not a new idea - and when pushed I don't recall you bringing anything new to this subject. But then that may have been your lack of willingness to engage with others.

But not in the sense usually associated with the word 'creationist'. If you are not going to share, then why bring it up at all? Is this an attack on Dawkins? I am not sure that this forum allows such unfounded attacks. What is it that you don't believe about `big bang' cosmologies? Maybe people here can help you - or maybe that is better off in another thread.

Simon - please stop with this rant and try not to cross you two similar threads. As I said in the other thread. If you have been attacked then use the report button. This is a good point. And because of this science can develop and scientists can change their opinions. Science is always to some extent 'work in progress' and new ideas are put forward all the time - and most are shown not to be good ideas!

I am not quite sure what you are asking - but are you thinking of waves on 4-d space-time that depend on some other 'external' parameter? Much like you think of EM waves taking values at (x,y,z) but depending on t? They are not special in this sense - you write h(ct, x, y, z) and this satisfies the 3+1 d wave equation. But then so does EM radiation.

The difference is that scientists say 'we don't know what happened at t=0'. Creationists say 'we do know what happened at t=0, God did it'. The difference is huge. This depends on what Christians you ask and what version of creationism you mean. There is no nonsense in saying 'we don't know'. This depends on what you mean. We think that whatever was at 't=0' was natural and it was some natural phenomena that started the expansion of the Universe. But again, we don't understand physics at this extreme.

Simon - if you are not going to share here, or more importantly submit a paper to a journal, then what is the point of this thread other than for you to simply insult people? Please try to keep this civil. Anyway, if you feel that someone has been unfair to you, and in particular has broken the rules (say with personal attacks) then please use the report button to notify the moderators. I assure you that they will take any report seriously and look into it.

Mmmmmm... yes it is. No, I would seek to publish it in a mainstream physics journal. Follows from, yes. Simon, what is it you really want here? What do you want to discuss? What do you hope to get out of these rants? I fear you will gain nothing and simply get banned.

All the data I have read tells me that gun ownership full stop is not good for your health. But this is another subject for another thread. What I am getting at is that allowing guns on a campus is not going to make the campus safer - there is no evidence so far that where they do allow guns the area is actually safer or that guns reduce crime - what guns on campus do is just increase the risk of accidents and mistakes. I really think that universities should make a stand here and not allow guns on campus whatever the law says - no institute should be forced to accept the NRA lies. Look at the evidence and not simply accept the BS that people cannot back up. The statistics are showing that owning a firearm does not actually reduce the chances of you being a victim of crime. This can be extrapolated to crimes on university and collage campuses - in fact the link I gave earlier talk about just this. For example, allowing female students to carry guns does not reduce their chances of a sexual assault - the FBI data tells us that very few women who own a gun are able to get to it quickly enough when in trouble. In fact, what the statistics tell us is that a woman is far more likely to get shot by her own gun that shoot a would be rapist. So once again, there is no evidence that a campus with guns is safer, the evidence is quite the opposite.

Explosion is not really the right word here - it gives the impression of something like a chemical explosion. We are not sure at all what happened very close to 't=0', but shortly after that we have a good picture. It is called the Lambda CDM model. You can make some great predictions using rather generic big bang models such as the abundance of light nuclei - and guess what? - these predictions fit well with what we observe. Again, you are just picking out gaps in our knowledge rather than brining anything to the table to discuss. Exactly how life emerged is not understood - well all accept that and take it to mean 'work in progress'. Life is what you make of it and you bring meaning to your own life. This is clearly not true. Not true, lots of religious groups have weapons - ISIS for example! Some of these people will be religious. So do something about it. The problem is that lots of people are brainwashed as children. So I would not link directly what one believes with intelligence.

This is not really the subject here - but this is not inline with my quick research. For one, owning a gun does not reduce your chances of being a victim of a crime and some studies have shown that allowing concealed carry has little effect on the levels of crime. Thus, the benefit is not really there. I question that there is any benefit here - only more risk of mistakes and accidents. Having people carry weapons is just asking for mistakes and accidents. Moreover, a university is where the brightest people go do study, learn and develop themselves - I do not see that carrying weapons on campus is consistent with that. Normal people don't sort there problems out with guns and in my opinion they have no place at universities. Read this for example https://www.thetrace.org/2015/11/campus-carry-self-defense-accidental-shootings-research/ (and maybe chase up the actual papers) The general point is the guns do not make a safer society. However, the main thing I question is if places of learning should fall victim of the myth that 'guns safe lives'.

There is plenty of evidence that gun ownership full stop is not good for your health. But anyway, we are discussing guns and concealed guns on university campuses (Texas in particular, but not just Texas) - which should be places of learning and development, not places where individuals should carry weapons. Please don't hijack this thread with your pro-gun stance - say something intelligent about guns in universitites and similar.

This does sound like sources rather than a mechanical medium - so where 'field lines start and end'. What is true is that accelerated charges create ripples in the electromagnetic field - but again we don't think of the charges as a medium.

Phi for All - like all things in life, there is a limit.

It is funny when people accuse you of being a sceptic as if that is a bad thing.

Yes, this is the proper length - which is the length as measured in the rest or comoving frame, i.e., the frame in which the ruler is stationary.

That brings no benefit... or do you think it does?

The ruler will be measured as being shorter - hence the term length contraction.

What do you mean by reality? For sure, in general other (inertial say) observers will measure the ruler to be a different length - and this depends on the relative velocity. Yes, the ruler 'tracks out' a 4 dimensional world sheet - it has a 3d volume and exists for some time. I don't follow - maybe you are taking some earlier analogies too far.

As far as the ruler is concerned it never changed - it was always 30cm tall as it measures itself.

Except this is not a theology, it is science. We can ask for evidence of the claims of big bang cosmologies and evolution - and we have plenty of evidence. Big bang cosmologies - yes I think lots of people will agree with you. But it works so well. The mathematics and the observations fit. We can only conclude that this crazy idea agrees with nature very well. Big bang cosmologies, such as the well supported Lambda CDM model, do not address the classical singularity at all. The models and observational evidence are quite independent of the initial singuarity. Anyway, there is a gap in our knowedge for sure. We can only 'rewind' our models so far. You seem now to be appealing to the 'God of the gaps' - as we don't understand something God or gods must have done it. It is a little worse than that as it is clear that you have no real insight in to the science you wish to belittle

New laws in Texas now allow students to carry guns - and in particular concealed handguns - on all campuses. http://www.bbc.com/news/world-us-canada-36948149 Is this not a bit crazy? Will it scare off potential students from other states and indeed international students? What about the saftey of staff? Armed students does not sound great when it comes to dealing with differnces of opinion - say in relation to grades. What are your thoughts on this?

Yes, electric charges act as sources of the electromagnetic field. You get electrical breakdown of the air (or whatever is in between the charges or charged objects) and a current flows. No - charge particles act as souces and sinks of the electromagnetic field. But that are not any kind of aether. We can see that light travels across vacuum - in the lab or across space - without the need for charged particles along the way. Like EM, this does not seem to be the case - objects with very little matter in between then interact gravitationally okay. You seem to be mixing the notion of sources with some mechanical aether.