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Very fast rocket 5 years ago

IIRC the light coming from in front of you gets blue shifted, each photon increasing in energy, and the count increases because of the geometric changes you see in the video (the angles in front seem to shrink).

Light from the rear red shifts (each photon has less energy), and there are fewer as some of the (formerly incident) photons "rotated" to the front.

(edit: typo)

(edit: didn't read the question closely, this is about approaching c, not exceeding it)

Fossil 6 years ago

It looks totally fine to me (lines are wrapping normally). Are you sure it's not something to do with your own browser?

This image [1] comes from "Converson to Islam in the Medieval Period" by Richard Bulliet [2]. The percentages inferred by Bulliet roughly track a sigmoidal curve. He makes an argument in analogy to the spread of a disease through a social network.

It should be noted that the deta is from Iran, but presumably the same arguments apply for Southeast Asia.

[1] http://4.bp.blogspot.com/-69BqAL9ARKg/T1WBF0NwxeI/AAAAAAAAAB...

[2] http://www.hup.harvard.edu/catalog.php?isbn=9780674732810

R generation 8 years ago

I think bit64 gives integer64, but like you I never need large integers - I don't do general purpose programming in R.

I wouldn't have said "shit source", but I think he's better viewed as a reasonable populariser than a proper source. He is up with the literature (in the sense that the day after a new paper is published, he blogs about it), but he's not an authority in any way, and some of what he writes about e.g. the gendered aspect of IE migrations is a bit florid and unsupported by facts, as far as I can tell. You'd never find a reputable scientist in the field (lets say someone from Reich or Willerslev's labs) pushing lines like that.

Regarding the Out of Africa (OoA) model, that is definitely still the consensus model. What is becoming clearer is that subsequent to the OoA event, there was substantial admixture within OoA populations, backflow into Africa, and introgression from Archaic Humans (i.e. interbreeding with Neanderthals etc). Razib refers to this as the "Braided streams" model, rather than a model where populations split and then remained isolated.

The real revolution in understanding seems to me to be the role played by human migrations in hte formation of modern populations (i.e. the refutation of the "pots not people" view popular since the 60s.

It was easyish to visit around 10 years ago - though there was a problem with Al Qaeda.

The civil war doesn't really seem to be a problem in Shibam iteself, (part of Hadhramaut, in the middle of the country, well in "red" territory in this map: https://en.wikipedia.org/wiki/Yemeni_Civil_War_(2015%E2%80%9...

Your biggest problem would probably be getting into Yemen itself. You'd need to get to the port of Mukalla and go overland from there.

In my experience most are, but there is also some work in operations management and optimisation, product design (e.g. financial products, digital products) and other areas.

I think marketing is the obvious first use case, but in large organisations there are often gains to be made looking at operational data.

It's not just the DHT22's accuracy that's a problem, it's the calibration.

I have 8 of these, and they are up to 30%RH off - both in terms of their readings relative to each other, and relative to the true RH of a saturated salt solution[1]. Moreover, some of them have a strange "stickiness" to certain levels.

I've heard good things about the BME280, and that's what I intend to replace my DHTs with.

[1] See e.g. http://www.omega.com/temperature/Z/pdf/z103.pdf