Strange

Just thought that was worth repeating. The fact of evolution has always been known. The ancient Greeks, among others, pondered many possible explanations. Eventually Wallace (and some guy called Darwin, apparently) managed to piece together all the necessary evidence to expand on earlier theories and show that natural selection is the "driving force". The "goddidit" answer is not only unsupported but deeply anti-intellectual as it shuts down any further enquiry.

The visible part of the nail root (that the nail grows from) is called the "lunula". So there is a connection there.

They are both "extruded" from an extended source. That's about it. One is molten rock, the other is a complex mix of proteins. Certain diseases can cause ripples in the nail which, I suppose, are a little bit like mid-ocean ridges. But that really is it.

Says who? Perhaps more importantly, when they cancel "each other out" they are converted to energy (so, you are right, there is still something).

That is just sloppy journalism (as noted by swansont in post #3).

This is a spectacularly bad analogy. For one thing, this is like saying that if you cut an animals head off, you will kill it. That doesn't prove that a head is "irreducibly complex". A CPU is not an example of irreducibly complexity. In fact, the CPU has "evolved" over many decades. So you could remove the caches from the CPU and it would still work. You could remove the superscalar pipelined architecture and it would still work. You could remove the hardware multipliers and it would still work. In fact, you don't need very much more than a few basic logic gates to have a working CPU. The same is true of all biological functions: there are simpler versions which will do something useful. That is just nonsense. You can have reduced fertility not just "fertile or not". And, of course, those organisms which are less fertile will be less likely to have offspring and hence less likely to pass on that deficiency: this is known by the complex technical term, "EVOLUTION". How can a rational person fail to notice any of the objections to their argument and just repeat the same thing? How can a rational person deny the existence of inherited characteristics, variation within populations and the effect of those variations on survival and reproduction? How can a rational person deny the existence of domesticated animals and plants?

Really? Well, here is a link to the paper itself, if that is more useful: http://arxiv.org/abs/1504.06604 I don't think anyone is suggesting that G is changing. That article says that the situation with regard to measurements of G is "not good" and mentions about half a dozen experiments to measure it. He also notes that the measured values differ by a few parts in 104 (much more than the errors in measurement). This seems entirely consistent with the paper referenced by the OP.

There is an anti-particle for each type of particle (some, like photons are their own anti-particle). But there is not the same amount of matter and anti-matter - the reason for this is one of the great mysteries of cosmology. However, if there were an equal amount of both, then they would have annihilated early in the universe's history and we would not be here to wonder about it! I'm not sure you really need to know the amount and distribution of mass in the universe to understand gravity. But it might help with understanding things like expansion. Also, the Eddington number probably isn't the right way to go about it. The modern estimate of the number of protons is derived from the estimated mass of the observable universe. It is thought to about 1080 which is quite close to Eddington's value.

John, rather than talking about clocks and things, why not address the science in the OP?

In many cases we have evidence of the steps involved. We also see evolution happening, so it would be pretty irrational to think it doesn't exist. Do you think domesticated animals and crops don't exist?

It is just a universal constant. Like c, α, μ0, ε0, e, etc. There is (as far as we know) no reason for it to change over time or place. (And absolutely no reason to imagine that magnetism has anything to do with it.)

Even if they were affected by changing G, they would all be affected in the same way and so no one would notice.

Interesting. But could you explain why you think it is relevant? The linked paper says ~10-14 G. So I think that is equivalent to about 10-48 kg/m3. Or about one electron in a cube 1 km on each side. So not a very significant mass equivalent. (I may well be out by a large factor!)

The gravitational effect of the energy of the magnetic fields is the same as the equivalent mass. Or to put it another way, if you somehow convert the energy to mass (using magic) then e=mc2 tells you what mass you would get (a really tiny amount as it would be a tiny energy divided by a really big number)

What do you mean by "related to mass"? It has a gravitational effect, equivalent to mass but that's all.

I have no idea what the magnetic field strength in different areas of space is. It will obviously be greater near stars than the interstellar or intergalactic space. And it falls off with an inverse cube law. But I have no idea what reasonable values would be. Looking at this: http://www.scholarpedia.org/article/Galactic_magnetic_fields and doing some rough mental calculations, my feeling is that it would be orders of magnitude less than the interstellar gas (which is a pretty serious vacuum). I don't have time to try and work out more accurate figures now...

But you could post the question the appropriate forum, then you might not need to be ...

All forms of energy (and mass) are a source of gravity. Magnetic fields have energy associated with them (I think) and so will have a (very small) gravitational effect.

Is this yet another "I'm not getting the answer I want so I am ignoring the answers" thread? If there are no such experts reading the thread, you could have a long wait ...

And, if anything, this result would show that G is independent of magnetic fields: there is a very weak geomagnetic field on Earth, but very, very strong magnetic fields around pulsars.

G is a universal constant and gravity has nothing to do with magnetic fields(*) so: no. (*) Apart from the fact that magnetic fields have energy and therefore can have a gravitational effect...

Maybe no one with expertise in chemistry is reading threads in "Astronomy and Cosmology" ...

I'm not sure that there would be a release of energy in such a process. Maybe you should create a thread to ask that in the chemistry sub-forum. Is this useful: https://en.wikipedia.org/wiki/Hydroxyl_radical#Astronomical_importance ?

Bad day at school?

Ironic that you post this using a device that is only possible because of our knowledge of quantum physics ... We are already travelling at over 99.99% of the speed of light (relative to something).