dennisgorelik | Entries tagged with science

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https://news.usni.org/2020/04/17/navy-cdc-to-study-covid-19-outbreak-on-carrier-theodore-roosevelt
“As of today, 94 percent of Theodore Roosevelt crewmembers have been tested for COVID-19, with 660 positive and 3,920 negative results,” according to Friday’s COVID-19 report from the service. “4,059 sailors have moved ashore.”

On Thursday, the Navy announced the identity of a Theodore Roosevelt sailor who died from COVID-19 complications.
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Theodore Roosevelt aircraft carrier is an optimistic case of Covid-19 fatality rate (because of younger and healthier military population vs overall society).
Out of 4,580 crewmembers - 1 crewmember died. That represents ~0.022% fatality rate.

If US population overall was as healthy as Theodore Roosevelt crewmembers are, then out of 330M people about 72,052 would die.
But realistically, the death rate would, probably, be closer to the Diamond Princess case (0.23% fatality rate).
If we assume more realistic fatality rate of 0.1%, then the US would have about 330,000 people died from Covid-19 (most of them undiagnosed).

Crossposts: https://dennisgorelik.livejournal.com/188650.html

Katie Bouman is a human face of the team that produced a black hole image that hit the news today:

2 years ago Katie delivered a TED talk about that image extraction efforts:
https://www.youtube.com/watch?v=BIvezCVcsYs

It is an interesting presentation, but I do NOT understand Katie's explanation about how they were going to minimize the bias [to "see" already predicted black hole visualization] while creatively interpreting inputs from sparsely placed telescopes around the earth.

Do you understand Katie's explanation?

Katie Bouman resume

How to Understand the Image of a Black Hole

Update:
Calibration Free Imaging

Update:
This posting is from ~2019-04-13
But I do not know how to set it back to that older date...

Crossposts: https://dennisgorelik.livejournal.com/171854.html

I find this picture fascinating.
It demonstrates several important concepts:
1) CT-scan and why it is needed.
2) How cancerous tumor looks like (in this case, Mesothelioma).
3) How key human organs look like on a CT-scan.

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https://en.wikipedia.org/wiki/File:Tumor_Mesothelioma2_legend.jpg
Malignant Mesothelioma, coronal CT scan.
Legend: the malignant mesothelioma is indicated by yellow arrows, the central pleural effusion is marked with a yellow star. (1) right lung, (2) spine, (3) left lung, (4) ribs, (5) aorta, (6) spleen, (7) left kidney, (8) right kidney, (9) liver.
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Other pictures by the same photographer: Stevenfruitsmaak Gallery.

Crossposts: https://dennisgorelik.livejournal.com/181584.html

It gets better:
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https://youtu.be/UGL_OL3OrCE?t=1177
19:37
What you can do is to use methods where you [have] do not need any calibration whatsoever and you can still can get pretty good results.
So here on the bottom at the top is the truth image, and this is simulated data, as we are increasing the amount of amplitude error and you can see here ... it's hard to see ... but it breaks down once you add too much gain here. But if we use just closure quantities - we are invariant to that.
So that really, actually, been a really huge step for the project, because we had such bad gains.
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"Вот тут мне карта и поперла".

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https://youtu.be/UGL_OL3OrCE?t=2242
37:22
And you can notice like at the bottom we get really terrible reconstruction, just cause if it fits the data very well, because you know it maybe wants to smooth out the flux as much as possible and we don't select things like that in the true data.
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I posted a comment below that video:
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19:39 "Calibration Free Imaging"
Does it mean that you were using measurements tools (telescopes) without prior calibration?
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but it got deleted... twice.

Update:
Discussing "not need any calibration whatsoever" on HN
"Calibration Free Imaging" (AKA scam)

Crossposts: https://dennisgorelik.livejournal.com/172709.html

https://youtu.be/UGL_OL3OrCE?t=1173
"So we do calibration at the same time as imaging"

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https://en.wikipedia.org/wiki/Calibration
Calibration in measurement technology and metrology is the comparison of measurement values delivered by a device under test with those of a calibration standard of known accuracy.
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The only image of "known accuracy" that these scientists had during black hole imaging -- was a theoretical image of how that black hole should look like.
But it is invalid to use that theoretical image as a self-proof that this theoretical image is correct.

So this team of "black hole photographers":
1) Took an extremely sparse signals from their several telescopes.
2) "Calibrated" their "signal interpretation" algorithm based on the theoretical black hole image (that they wanted to see).
3) Made "calibrated" "signal interpretation" algorithm to interpret sparse signals.
4) Not surprisingly, their "signal interpretation" algorithm produced theoretical black hole image that these "photographers" wanted to see.

What these "black hole photographers" did is NOT science, but scientific scam.

That explains why these "photographers" instead of photographing Sagittarius A (that is 26 thousand light years away) chose to photograph Messier 87 (that is 53 million light years away -- 2000 times further!)

At shorter distances there is not enough room for creative "calibration" of sparse signals.

See also:
Extracting a black hole image from "sparse telescope matrix"

Crossposts: https://dennisgorelik.livejournal.com/172298.html

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Franklin Veaux makes fun of Greenpeace misconceptions.
We don’t have the ability to harm and destroy the planet.

We do have the ability to harm and destroy things living on the planet.

We are not unique or even particularly unusual in that regard.

If you were to make a list of the top most ecologically destructive life forms the planet has ever seen, we would not be #1. Cyanobacteria get that honor by a huge margin.
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Crossposts: https://dennisgorelik.livejournal.com/147572.html

https://www.youtube.com/watch?v=n691pLhQBkw

Transcript

Crossposts: http://dennisgorelik.livejournal.com/140637.html

I was surprised today that very few people understand what falsifiability means and how to apply that useful evaluation tool.

Of course I knew pretty well, that an average person has no idea about what Popper's criteria of falsifiability is.
But most of my online friends do not understand what "Falsifiability" means either.

It is a pity, because Falsifiability criteria - is a very powerful tool that allows to quickly separate potentially useful theories from pseudo-scientific scam.

Hopefully my friends understand better what testability is (the meaning of "testability" and "falsifiability" overlaps a lot).

Crossposts: http://dennisgorelik.livejournal.com/139843.html

Watch on YouTube

That interview causes cognitive dissonance.
Of course UAE is an advanced country with GDP per Capita $43K (below the US, but above UK).
But UAE not exactly the most technologically advanced country. They are on a consuming side of technology.
So that interview was a little bit unexpected.

Both Elon Musk and the interviewer - Mohammed Al Gergawi (a Minister of Cabinet Affairs of the UAE) were a little bit nervous.
Al Gergawi mostly asked Musk his list of prepared questions (a pretty good list) and almost did not interrupt Musk. That resulted in a "psychologist session" for Musk: he drifted away from more generic questions (such as "why are you pushing the limits?") toward the topics he likes to tals about (how he made decision about building reusable rockets).

One time during interview Al Gergawi Musk and it added some embarrassment to both Musk and Gergawi:
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Al Gergawi: Why it is dangerous? I mean there is two view; one view is the artificial intelligence to help humanity, there is another school of think or thought is artificial intelligence as a threat to humanity. Why is it?

Elon Musk:
Well, I think it's both. You know – it's like – one way to think of it is, imagine we're going to be visited – imagine you're very confident that we're going to be visited by super intelligent aliens in, let's say, 10 years or 20 years at the most - super intelligent.

Al Gergawi:
So you think within 20 years ...

Elon Musk: Yeah so.

Al Gergawi: ... we'll have alien in Earth?

Elon Musk: [Surprised] Ha-ha. [Switching to a serious tone] Well, digital super intelligence will be like an alien.

Al Gergawi: It will be like an alien?

Elon Musk: Yeah.

Al Gergawi: But my question is: "do you think there is either intelligent life outside there"?

Elon Musk: It seems probable, but I think this is one of the great questions in physics and philosophy is where are the aliens; maybe they're among us, I don't know. Some people think I'm an alien. [Applause]
Not true. Not true.
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Transcript

Crossposts: http://dennisgorelik.livejournal.com/129109.html

It turns out that some scientists played dirty while trying to discredit religious resistance to their discoveries.

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https://en.wikipedia.org/wiki/Myth_of_the_flat_Earth
The myth of the flat Earth is the modern misconception that the prevailing cosmological view during the Middle Ages in Europe saw the Earth as flat, instead of spherical.

During the early Middle Ages, virtually all scholars maintained the spherical viewpoint first expressed by the Ancient Greeks. From at least the 14th century, belief in a flat Earth among the educated was almost nonexistent
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The 19th century was a period in which the perception of an antagonism between religion and science was especially strong. The disputes surrounding the Darwinian revolution contributed to the birth of the conflict thesis, a view of history according to which any interaction between religion and science would almost inevitably lead to open hostility, with religion usually taking the part of the aggressor against new scientific ideas.

https://en.wikipedia.org/wiki/Conflict_thesis
The "conflict thesis" proposes that there is an intrinsic intellectual conflict between religion and science and that the relationship between religion and science inevitably leads to public hostility. Although the thesis still existed in popular imagination as of 2002, historians of science do not support the original form of the thesis, since it has been discredited.
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