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Keyshon Scientists Protest Censorship in Cosmology

It’s not really a Big Bang “alternative” at all. It is possibly an explanation of how the early Big Bang got going.

Keyshon Why is there no semantic ontology of sentiment in academic citations?

In Anthony Grafton's The Footnote: A Curious History, he claims that citations practices in the field of history have the tendency to use "cf." -- which normally means something like "compare with this reference" -- to mean "compare with this reference (which is actually wrong and stupid)".

So you have to watch out for the possibility of ironic or sarcastic references, which may vary from field to field.

Keyshon Minoan language Linear A linked to Linear B in new research

Written Arabic and Hebrew often omit vowels; the actual spoken languages do not, of course.

Keyshon First images from James Webb telescope exceed expectations

Not “way” less, because most stars are lower mass than the Sun and thus have longer lifetimes (~ trillions of years in the case of red dwarfs).

Keyshon First images from James Webb telescope exceed expectations

It’s actually no problem mathematically to have toroidal topology and flat geometry. (The classic Asteroids video game, where your ship can go off the top of the screen and come in at the bottom, or similarly with the left and right edges, is an example of a flat 2D space with the topology of a torus.)

Keyshon First images from James Webb telescope exceed expectations

That’s Olber’s Paradox, of course, and it relies on three assumptions: 1. The universe is infinitely large and 2. The universe is filled with stars and 3. The universe has been this way forever.

It turns out #3 is wrong, so it’s still possible we live in an infinite universe.

(Imagine an infinite, unchanging universe filled with stars that magically popped into existence a billion years ago. You wouldn’t have a uniformly bright sky because even though every line of sight will theoretically terminate on a stellar surface, in most cases there hasn’t been enough time for light traveling along that line of sight — e.g. from a star 10 billion light years away — to reach your eyes.)

Keyshon A new history of Byzantium reveals the inner workings of a late antique empire

Uh, no.

1. You're way overestimating the wealth of the Near East in the time period we're talking about. If you look at Maddison's estimates of historical GDP (e.g., https://en.wikipedia.org/wiki/List_of_regions_by_past_GDP_(P...), you can see that circa 1000, "Western Europe" had a GDP of about 10.9 billion (1990) USD, slightly below "West Asia's" 12.4 billion. But by 1500, Western Europe has ballooned 44.2 billion, while West Asia has fallen to 10.5 billion.

2. Italian merchants had regular access to the Near East throughout the Middle Ages and Renaissance, so "suddenly the West had easy access to trade with the East after Lepanto" is not even remotely true.

3. Lepanto's significance even in the context of the 16th Century Mediterranean is highly debatable; arguably, the most it did was to halt further westward expansion by the Ottomans, while they solidified their hold over the Eastern Mediterranean (they did, after all, rebuild their fleet within a year). See, e.g. https://www.historytoday.com/archive/head-head/how-important...

4. The most significant transfers of "knowledge" happened earlier, during the 12th Century Renaissance (translation of Arabic works and Arabic translations of Greek works) and the Italian Renaissance (translation of additional Greek works); continued transfer is evident in the apparent presence of 14th and 15th Century Arabic mathematical and astronomy texts in early 15th Century Italy, where they influenced Copernicus. And, of course, the transmission of other forms of knowledge and technology (compasses, paper, new agricultural products like citrus fruits, rice, and sugar, etc.) occurred throughout the period.

Keyshon A new history of Byzantium reveals the inner workings of a late antique empire

The Ottomans did not get a monopoly on eastern routes until they conquered Mameluke Egypt in the early 1500s. Western European (particularly Portuguese) attempts to go "the other direction" started in the 1400s.

Keyshon A new history of Byzantium reveals the inner workings of a late antique empire

Note that the oldest version of that story is due to a Christian Arab writing centuries later, complaining about all the bad things Muslims have done. There's no credible evidence from a non-axe-grinding source that anything like that happened.

Not to mention the fact that the Library had ceased to exist by the 4th Century, long before Omar showed up.

(Though I agree with you that the original comment looks like a recycled version of the Omar story.)

Keyshon A new history of Byzantium reveals the inner workings of a late antique empire

Uh, no. The Enlightenment -- which was a phenomenon of Western and Central Europe, not the Mediterranean -- was in no way affected by Turkish naval control of the (Eastern) Mediterranean.

Keyshon A new history of Byzantium reveals the inner workings of a late antique empire

Medieval Christians weren’t nearly as hostile to pagan works as you imply. Julius Caesar, Cicero, and Virgil were regularly copied and read. (And the enthusiasm with which Arabic translations of pagan Greeks like Aristotle and Ptolemy — and Muslim thinkers as well — were translated into Latin in the 12th Century certainly doesn’t reflect some “nothing but the Bible” mentality.)

The problem with Greek works is that they were no longer readable (since literacy in Greek disappeared with the fall of the Western Empire), and so there was no interest in copying them.

Keyshon Nearly 1k mysterious strands revealed in Milky Way’s center

The reported angular resolution (in the main paper: https://arxiv.org/abs/2201.10541) is 4 arcseconds. This is radio interferometry, which makes for better resolution, but it’s at a very low frequency (centered around 1.28 GHz = about 23 cm), which makes for worse resolution.

Keyshon Tabby's Star

OK, you're really not making much sense. I mentioned exoplanets because that was a (barely) plausible interpretation of something that was a "hot field in modern astronomy but was barely a thing when JWST began", since the preliminary studies for JWST did happen in the mid-1990s, when exoplanets were first beginning to be found. The actual serious design work, though, was in the early 2000s, when exoplanets were definitely a hot topic.

But if what you really mean is "within the solar system" (which, um, excludes "Tabby's star"), well... "barely a thing when JWST began" is complete nonsense. I mean, studying things within the solar system is something astronomy has been doing for literally thousands of years. (And, no, it hasn't suddenly become "the hot field" in any sense, leaving aside the point that there are multiple things that might be considered "hot fields" at the moment, and that there's never a single "hot field" anyway.)

JWST is perfectly useful for solar-system science: there are about 22 approved Cycle 1 General Observer proposals in that field, including one specifically meant for any "interstellar object" (like 1I/'Oumuamua or 2I/Borisov) that might show up during the first year: https://www.stsci.edu/jwst/phase2-public/2337.pdf

And the second-largest set of Guaranteed Time Observation proposals (proposals from "scientists who helped develop the key hardware and software components or technical and inter-disciplinary knowledge for the observatory"), after "Extra-solar Planets", is "Solar System": https://www.stsci.edu/jwst/science-execution/approved-progra...

Keyshon Tabby's Star

Of course JWST is an instrument for studying exoplanets (among other things). Something like 24% of the first year’s approved observing proposals are for doing just that. There are coronagraphs in two of the main instruments, all specifically meant for exoplanet observations.

https://eos.org/features/overture-to-exoplanets

Keyshon The Universe Is Expanding Faster Than It Should Be

This is known as the “tired light” hypothesis, and there are a number of problems with it; see https://www.astro.ucla.edu/~wright/tiredlit.htm .

Keyshon The Universe Is Expanding Faster Than It Should Be

The observations in the 1930s you allude to were of the motions of galaxies in galaxy clusters. The rotation-curve measurements for individual galaxies started in the 1970s and really took off in the 1980s.

"Tidal effects" are a non-starter, and do nothing to explain galaxy rotation curves. Nor do they explain the excess motions of individual galaxies in galaxy groups and clusters, or the excess pressure of hot, X-ray emitting gas in groups and clusters -- all of which requires either some kind of dark matter, or some kind of alternate theory of gravity, or both.

(I notice that I pointed out the ignorant nonsense of that video when you posted a link to it 7 months ago -- https://news.ycombinator.com/item?id=27085979#27090683)

Keyshon The Universe Is Expanding Faster Than It Should Be

Kaiser's presentation doesn't suggest you can do the measurement for individual clusters; the example analysis is from Wojtak et al. (2011), which is similar to Mpetha et al. in using thousands of galaxies and thousands of clusters.

The Broadhurst & Scannapieco discussion about X-ray studies is interesting and potentially promising, but no one seems to have tried doing for real.

Keyshon The Universe Is Expanding Faster Than It Should Be

It wasn't clear to my why you said what you did. (Good to know it was just an editing failure.) Sometimes people get confused and think "dark matter halo" means all the dark matter is outside the main body of the galaxy, so I was pointing out that this isn't the case.

Keyshon The Universe Is Expanding Faster Than It Should Be

The reddening is because of the additional mass of the dark-matter-containing structures, and also because the distribution of the dark matter into halos allows for slower orbits of stars and gas clouds, thus suppressing their non-gravitational non-cosmological redshifts. (In an edge-on spiral galaxy without dark matter we would see a greater difference in the blueshift of one extreme tip of the thin disk and the redshift of the opposite extreme tip of the thin disk, compared to the same spiral galaxy with dark matter; the light-and-radio from the central bulge would be less redshifted in the absence of dark matter).

This is the exact opposite of the truth. An edge-on spiral galaxy without dark matter would have less extreme observed rotation velocities (comparing the blueshifted and redshifted sides of the disk), because only the visible mass (stars and gas) is relevant. But in practice we see higher rotation velocities (greater difference between blueshifted and redshifted sides) than can be explained by just the visible mass, and so we have to postulate extra mass in the form of "dark matter" in the galaxy.

(Dark matter halos are not just dark matter outside the visible galaxy, they extend all the way to the centers of galaxies, and in fact become denser the closer to the galaxy center you get. Of course, the visible matter also becomes denser the closer to the center you get, and usually faster than the dark matter does, so the central regions of massive galaxies are dominated by the visible matter. But there's still dark matter there, and in some dwarf galaxies, the dark matter even in the central regions.)

Keyshon The Universe Is Expanding Faster Than It Should Be

One important caveat to all this is that the gravitational redshift for a galaxy or galaxy cluster is an incredibly tiny effect. For example, the mean gravitational redshift for massive galaxy clusters has been measured (e.g., link below), and has a value of ~ 10 or 15 km/s. This can be compared with the typical motions of galaxies within a cluster (dispersions of ~ 1000 km/s) and the cosmological redshift of the clusters (for the sample in the paper I linked to, it's equivalent to an average Doppler shift of ~ 50,000 km/s).

In order to make that measurement, the authors had to combine redshift measurements for ~ 20,000 galaxies from ~ 2,500 different clusters; as they note, it's impossible to detect the effect for just a single cluster: "... even assuming that every galaxy in a cluster could be spectroscopically measured, there are simply too few galaxies to allow the statistical detection of a non-zero gravitational redshift."

So while it's technically true that adding dark matter to a galaxy would increase its gravitational redshift and thus its total observed redshift, this effect is immeasurably small.

Mpetha et al. (2021), "Gravitational redshifting of galaxies in the SPIDERS cluster catalogue" https://arxiv.org/abs/2102.11156

Keyshon A Tunguska size burst destroyed Tall el-Hammam, Bronze Age city in Jordan Valley

The paper in question is by people from a variety of institutions (none of them being Veritas International University). Early in the paper there is this comment:

"After eleven seasons of excavations, the site excavators [i.e., the folks affiliated with Veritas International University] independently concluded that evidence pointed to a possible cosmic impact. They contacted our outside group of experts from multiple impact-related and other disciplines to investigate potential formation mechanisms for the unusual suite of high-temperature evidence, which required explanation."

Keyshon A Tunguska size burst destroyed Tall el-Hammam, Bronze Age city in Jordan Valley

The suggestion in the article is that the bolide impact (or airburst) was well outside the city, to the SW, since a lot of the evidence suggests a blast moving from SW to NE through the city.

Keyshon Why do so many people move to the Falkland Islands? (2009)

And screw the people who actually live there, right?

A better way to think about this is to consider the case of Saint Pierre et Miquelon, which are two islands off the coast of Canada -- literally 19 km away, and so much closer than the Falklands are to Argentina. They are French territory, inhabited by French citizens. And (aside from occasional disagreements about who gets to explore for undersea resources in the vicinity of the islands) Canada really doesn't seem to have a problem with this, because (in this area, at least) Canada is a more mature nation than Argentina.

https://en.wikipedia.org/wiki/Saint_Pierre_and_Miquelon

Keyshon Matt Damon quickly explains why they don’t make movies like they used to

From the video, the question is, in effect, “Why don’t they make movies like they did in the 1990s any more?”

Keyshon Finish Your Stuff (2015)

The “leaders in editing software” are arguably Avid’s Media Composer, Adobe Premiere pro, and Apple’s Final Cut Pro X, none of which have free versions.

The free version of Da Vinci Resolve was released back when it was still a color-correction tool, before it started adding meaningful editing capabilities. So, no, I don’t think Shotcut is relevant.

Keyshon Dark Matter: The Situation Has Changed

Dyson spheres would glow in the mid- and far-infrared (re-radiating energy absorbed from the enclosed star), and so would not be "dark".

Keyshon Dark Matter: The Situation Has Changed

Friction in this context refers to "dynamical friction", where massive objects -- e.g., dense cluster cores -- moving through a medium of many small masses -- e.g., DM particles -- will experience gravitational drag and slow down.

https://en.wikipedia.org/wiki/Dynamical_friction

Keyshon Dark Matter: The Situation Has Changed

This is rather overstated (especially the "incredibly unlikely" bit).

The best attempt I've seen to summarize this is in this paper https://arxiv.org/abs/1412.7719 which argues that there's roughly a 10% chance of getting something as extreme as the Bullet Cluster under Lambda-CDM. So, mildly unlikely, but not even approaching the (problematic) P < 0.05 threshold that's emblematic of the "replication crisis" in fields like experimental psychology.

Keyshon Dark Matter: The Situation Has Changed

On the other hand, the center of a star is much hotter than the periphery, so there are potentially more accessible states in phase space for the particles in the former location (it's "can be in N positions in phase space", which depends on the available physical space and the possible velocities).

Not that this would affect California vs Rhode Island analogies, unless you could demonstrate that things in Rhode Island were a lot hotter...

Keyshon Dark Matter: The Situation Has Changed

In fact, assuming extra undetected mass to explain the anomalous motions of galaxies in clusters (as originally noted by Fritz Zwicky in the 1930s) was at least partly correct, because we now know that galaxy clusters contain rarified, extremely hot intergalactic gas (detectable only by its X-ray emission) in amounts equal to five or ten times the stellar mass of the galaxies. You still need even more mass in some as-yet-unidentified form (i.e., "dark matter") to fully explain cluster dynamics, but the basic hypothesis was at least partly successful.

(The "undetected mass" hypothesis also turned out to be successful in the cases of binary stars, including things like Sirius B, where the companion turned out to be a bizarre type of star never before seen or theorized.)

And, no, dark matter can't be distributed "arbitrarily": its distribution has to be consistent with gravity acting on an initially almost-uniform distribution with small cosmological perturbations (consistent with those seen in the cosmic microwave background).