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Astrophysicists unveil biggest-ever 3D map of Universe: The map is very isotropic and homogeneous, the large scale galactic filaments are not as apparent on this scale. Discussion? Isotropic: .(of an object or substance) having a physical property which has the same value when measured in different directions. .(of a property or phenomenon) not varying in magnitude according to the direction of measurement. Homogeneous: .of uniform structure or composition throughout. Reference: https://www.ctvnews.ca/sci-tech/astrophysicists-unveil-biggest-ever-3d-map-of-universe-1.5030682

Hello All I found this in a London garden I don't know if it came from here or not, Grey with white/beige and brown. What are the elements/compounds here please? Regards

No I don't think the first one is granite or even igneous. It looks like a fine grained sandstone or siltstone to me, perhaps a grewacke. https://en.wikipedia.org/wiki/Greywacke This would be consistent with the Faro peninsula, which is a small sedimentary piece on the edge of the alpine mountain building area in Iberia. (the Variscan Orogeny https://en.wikipedia.org/wiki/Variscan_orogeny The pebble does not look beach rounded but river worn. Perhaps it was brought down by the Chanca river from the mountains to the north and east. The second pebble definitiely looks like some form of volcanic glass, probably obsidian. It seems to be layed on duller form of lava, which is very common. The base layer appears to have bubbles or other structure, characteristic of other forms of lava. If that was basalt the pebble would be quite heavy. Again this would have formed during the Variscan. Yes the various discolourations of the veins in the samples will be dues to impurities in the quartz. Iron compounds give the brown colour. It should be noted that the quartz veining is quite different from the micro intrusions of liquid rock during vulcanism. The is no metamorphosis (cooking) of the parent rock along the boundaries. Quarz is slightly soluble in rainwater of geological timescales so precipitates out as the solution percolates small fissures and the water evaporates.

I was replying to the OP's example. In your example the grey is lighter in colour and clearly pitted (not smooth), it may be granite but a rotten version.

You're thinking of completeness. Consistency means that no statement can be proven both true and false.

Is there any way to perform any theoretical experiment to show that ,in the absence of a mind such a "mindless" universe could exist without any property associated with time ? Could we go back in time to an epoch where we can be certain that life (that is where "mind" is to be found, I assume) had not yet taken root? If we were able to hypothesize such a scenario how would life get established subsequently if time was not part of the scenario? The universe would be permanently stuck in "3rd gear" ...wouldn't the universe need time to progress to a state where there could exist a mind that you suggest operates on a 3+1 basis? (ie time is inherent in minds but not in the "inert" universe)

You would likely find many more of these on the beach at the base of a basaltic cliff. The white veins are quartz that have permeated the basic fine grained black rock after it was formed, but before pieces broke off to form the beach pebbles. The shape will have resulted from water action 'tumbling' pieces eg on a pebble beach. Cornwall is a good place to look for such pebbles. A scale is a good idea to add to a photo such as yours.

*Tucks Universe back into pocket* Balloon example is all good until someone asks you about those dots expanding or us colliding with Andromeda, lol.

Grown men don't play with dolls, Endi. Picture your typical simulation of an expanding universe, a balloon with dots on it. As you pump air into the balloon, it gets bigger and the dots separate just like galaxies do. There is no center to the surface of the balloon, no matter if finite or infinite. For eternal inflation, picture multiple 'aneurysms' on the surface of this balloon; areas where a smaller sphere starts expanding on the surface of the original balloon. In real space-time these new 'aneurysms' would be separated from the original by an event horizon, but in our balloon analogy they are still connected so that air can be pumped in. As the 'aneurysms' expand, any dots you draw on them will again start to separate like galaxies do, and again, there is no center to the surface of the 'aneurysm', whether finite or infinite. Actually eternal inflation can have 'aneurysms' on top of 'aneurysms' on top of the original balloon, but space- time is only represented by the surface of the balloons/aneurysms in this analogy.

The great African Rift Valley has been known about for hundreds of years, and stretches from the Middle East to below the 'horn' of Somalia. It is actually separating three plates; The Nubian plate, which is most of Africa, is receding from the Arabian plate, across the Red Sea and Gulf of Aden, fairly quickly, while the Eastern sliver of Africa, including Somalia's horn, is receding much slower. The separation seems to be subject to 'spurts' of activity, as this latest trench opened up in 2005. It will still take millions of years for a sea to separate the two parts of Africa.

https://ncatlab.org/nlab/show/principle+of+omniscience here’s a simpler one...

'Anti-realism'? Not quite. Kant is a 'grand synthesis' of empiricism (all knowledge comes through the senses') and rationalism (the only way to understand reality is by reason).

I wasn't aware of this branch of maths. Thanks a lot, Studiot. +1 I've found this other one: https://plato.stanford.edu/entries/mathematics-constructive/ Stanford's Encyclopedia of Philosophy has helped me a lot in the past (to understand the Kochen-Specker argument in QM, for example).

This is a genuine sub sub branch of Pure Mathematics which is very obscure. Try reading this Wikipedia has a simple offering for once https://en.wikipedia.org/wiki/Limited_principle_of_omniscience Then read a full blooded paper from Birmingham University https://www.cs.bham.ac.uk/~mhe/papers/omniscient-journal-revised.pdf Avoid the religious books by Paul Tranter They are not connected. https://books.google.co.uk/books?id=I8bKDwAAQBAJ&pg=PA69&source=gbs_selected_pages&cad=2#v=onepage&q&f=false