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Untangling the Galaxy I: Local Structure and Star Formation History of the Milky Way
Gaia DR2 provides unprecedented precision in measurements of the distance and kinematics of stars in the solar neighborhood. Through applying unsupervised machine learning on DR2's 5-dimensional dataset (3d position + 2d velocity), we identify a number of clusters, associations, and co-moving groups within 1 kpc and |b|<30∘ (many of which have not been previously known). We estimate their ages with the precision of ∼0.15 dex. Many of these groups appear to be filamentary or string-like, oriented in parallel to the Galactic plane, and some span hundreds of pc in length. Most of these string lack a central cluster, indicating that their filamentary structure is primordial, rather than the result of tidal stripping or dynamical processing. The youngest strings (<100 Myr) are orthogonal to the Local Arm. The older ones appear to be remnants of several other arm-like structures that cannot be presently traced by dust and gas. The velocity dispersion measured from the ensemble of groups and strings increase with age, suggesting a timescale for dynamical heating of ∼300 Myr. This timescale is also consistent with the age at which the population of strings begins to decline, while the population in more compact groups continues to increase, suggesting that dynamical processes are disrupting the weakly bound string populations, leaving only individual clusters to be identified at the oldest ages. These data shed a new light on the local galactic structure and a large scale cloud collapse.
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The edge on view and face view illustrations do look composed of string like shapes.
The video is called "Tracing Strings" but they don't explain the differences in appearance.
Also, the generation of the maps of these star groups is enmeshed with their understanding of star "age" which I think can seriously bias the results.
I am in general agreement with the EU explanation of stars, and galaxies, existing along Birkeland current filaments(strings).
However, globular clusters of stars have seemed, to me, to present something else. The EU says that these stars are all on filaments, but the photos don't suggest a filamentary pattern.
The EU posits that a very strong Z pinch of current is the originator of major bodies of matter, including stars and provides the ongoing energy to maintain star life.
However, I would suggest that strong pinches might not be needed to power an ongoing star once the massive body is formed. I am more inclined to see stars as collectors, and organizers, of plasma energy, as long as there is enough in its area, and that might lead toward a better explanation of globular clusters of stars.
Filaments might have higher plasma density areas which could support star life without a strong "pinch" to drive each star.
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These time it called "artificial intelligence".
In fact neural network is just a polynomial - could a polynomial be intelligent?
There are a lot of good reading on Rodney Brook website:
https://rodneybrooks.com/bothersome-bys ... ving-cars/
https://rodneybrooks.com/forai-the-orig ... elligence/
The theory of neural network does not exist. Not even one theorem.
How they are working is a miracle. Humans trying to model neurons, which probably giving us a consciousness. At least some scientists think so. The science estimate how certain species think by the number of their neurons.
Take a look at amoeba. It reacts to light, salinity, food, temperature, etc. The number of neurons is zero!
People overestimate what neural network could do. They could do only those things that human been "teach" them. Nothing new could be discovered. If you "teach" them to find a string then it will find a string.
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