Blog Archive 2015

All posts from 2015.

2015 October 05

originally posted on facebook

Visualizations of data from a neutrino detector – very cool

http://imgur.com/a/G6EE6

Picture of the sun taken at night by the above neutrino detector

https://newhumanist.org.uk/articles/2402

2015 October 01

originally posted on facebook

In PHP:

>>> 0x0 +2
4
>>> 0x0 +3.5
6.5
>>> 0x0 +2e1
757

https://www.reddit.com/r/lolphp/top/?sort=top&t=all especially see 1, 3, 7, 13, and 15

2015 September 25

originally posted on facebook

“Turns out this is not Brady’s first water glass heist. He also took the glass used by President Obama at his first inauguration.”

Washington Post

2015 September 12

originally posted on facebook

Fun fact: the sum of $1/(ab)^2$ over all relatively prime pairs of positive integers $a$ , $b$ is rational. This is not true if you remove the “relatively prime” restriction.

Short proof… that sum equals

$\prod_{\text{prime } p} \left(1 + \frac 2{p^2} + \frac 2{p^4} + \frac 2{p^6} + \cdots\right) = \prod \frac {1 + 1 / p^2}{1 - 1 / p^2} = \prod \frac {1 - 1 / p^4}{(1 - 1 / p^2)^2} = \frac {\zeta(2)^...$

where $\zeta$ is the Riemann zeta function. Since $\zeta(k)$ is equal to $\pi^k$ times a rational when $k$ is positive even, the $\pi$ s cancel and the result is rational, in fact $5/2$ . If you remove the restriction you get $\zeta(2)^2 = \pi^4 / 36$ which is irrational. You can make other combinations of $\zeta$ s so that the $\pi$ s cancel to get other rational infinite summations, for example the sum of $1/(abc)^2$ where $a$ is squarefree and divides $b$ should give $\zeta(2)^2 \zeta(4) / \zeta(8) = 35 / 12$ , and in both examples replacing the exponent 2 by any even integer also works.

2015 August 17

originally posted on facebook

For the second time this year, Lenovo is found to ship computers with malware preinstalled. This time it is a rootkit in the bios that replaces a Windows system executable with one which (on boot) installs various Lenovo software and downloads and installs drivers from the Lenovo website (over a nonsecure connection!). Thus even a clean reinstall of Windows does not get rid of the extra software.

https://arstechnica.com/information-technology/2015/08/lenovo-used-windows-anti-theft-feature-to-install-persistent-crapware/

Earlier this year, Lenovo was found to ship computers with “Superfish”, which installs a fraudulent root certificate so that it can spy on, modify, and remotely transmit users’ “secure” internet traffic. Furthermore it accidentally breaks the security entirely so that anyone else on the same network can also spy on or modify the secure traffic.

Slate

For completeness’ sake, last year Lenovo was found to ship computers with a browser hijacker called “Conduit”.

Wikipedia

https://www.shouldiremoveit.com/Lenovo-Browser-Guard-119380-program.aspx

2015 August 08

originally posted on facebook

https://slatestarcodex.com/2014/04/28/the-control-group-is-out-of-control/

Very interesting analysis, I think I got this link from Sam E. Be sure to check out the paper mentioned in section IV:

http://www.richardwiseman.com/resources/staring1.pdf

2015 August 03

originally posted on facebook

I learned recently that pre-main sequence stars (those fueled by their own gravitational collapse) are typically much brighter, by up to an order of magnitude, than their successor main sequence stars:

Wikipedia

The reason for this is that the young star has comparable surface temperature to a mature star while being physically much larger, so gives off more light. In fact, for fully convective stars the surface temperature is almost solely a function of the mass of the star and largely independent of its radius:

Wikipedia

Unrelated:

Wikipedia

YouTube

2015 July 12

originally posted on facebook

“Father Gary Thomas, pastor at Sacred Heart Catholic Church in Saratoga, Calif., and the exorcist for the Diocese of San Jose, said he has seen notable improvements after exorcising homes and when he re-dedicated a church.

However, he is cautious about the idea of exorcising an entire country.”

http://www.ncregister.com/daily-news/does-the-us-need-a-nationwide-exorcism

Maybe someone should just exorcise all of spacetime and get it over with. Although this raises the obvious question: does exorcism travel faster than light? The potential applications are clear.

2015 June 24

originally posted on facebook

“The Hague District Court has ruled today that the State [of the Netherlands] must take more action to reduce the greenhouse gas emissions in the Netherlands. The State also has to ensure that the Dutch emissions in the year 2020 will be at least 25% lower than those in 1990. […]

The State must do more to avert the imminent danger caused by climate change, also in view of its duty of care to protect and improve the living environment. The State is responsible for effectively controlling the Dutch emission levels. […] the State should not hide behind the argument that the solution to the global climate problem does not depend solely on Dutch efforts. Any reduction of emissions contributes to the prevention of dangerous climate change and as a developed country the Netherlands should take the lead in this.

With this order, the court has not entered the domain of politics. The court must provide legal protection, also in cases against the government, while respecting the government’s scope for policymaking. For these reasons, the court should exercise restraint and has limited therefore the reduction order to 25%, the lower limit of the 25%-40% norm.”

https://www.rechtspraak.nl/Organisatie/Rechtbanken/Den-Haag/Nieuws/Pages/State-ordered-to-further-limit-greenhouse-gas-emissions.aspx

The decision was made on the basis that the Dutch government has a duty to take “appropriate” steps to protect lives within its jurisdiction, including from foreseeable harm. This is (to me) a very unexpected ruling, which will hopefully have impacts on other countries either acting individually or collectively in the upcoming climate change conference in December.

NYT

2015 June 13

originally posted on facebook

https://waitbutwhy.com/2013/08/putting-time-in-perspective.html

2015 April 21

originally posted on facebook

Measurements of the gravitational constant vary sinusoidally:

https://phys.org/news/2015-04-gravitational-constant-vary.html

2015 February 23

originally posted on facebook

Since September, Lenovo has been shipping laptops with pre-installed malware that spies on all network activity – including encrypted – and sends it to a remote server under the guise of injecting targeted ads (“to assist customers with discovering products similar to what they are viewing”). Naturally the company that sells this malware did such a bad job of it (the password to unlock the SSL private key is “komodia”, the name of the company) that as a side effect, others on the same network as an infected computer can also view or modify any encrypted network traffic from that computer.

Slate

https://www.theverge.com/2015/2/19/8069127/superfish-password-certificate-cracked-lenovo

https://www.theverge.com/2015/2/19/8067505/lenovo-installs-adware-private-data-hackers

http://support.lenovo.com/us/en/product_security/superfish

https://blog.erratasec.com/2015/02/extracting-superfish-certificate.html

2015 February 04

originally posted on facebook

After careful examination of the discography of Korean pop group 4Minute I have determined that they should be renamed 3Minute19Second (with a standard deviation of 40 seconds).

2015 January 01

originally posted on facebook

A brief glimpse into the insightful mind of Darwin, and of some of the very beginnings of statistics.

“Fisher’s analysis was only possible because Darwin had designed his experiment so well. In fact, Fisher was often frustrated with the quality of other people’s experiments. ‘To call in the statistician after the experiment is done,’ he said, ‘may be no more than asking him to perform a postmortem examination: he may be able to say what the experiment died of.’”

https://www.sciencenews.org/article/darwin-reluctant-mathematician

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2015 December 26

2015 November 23

2015 October 05

2015 October 01

2015 September 25

2015 September 12

2015 August 17

2015 August 08

2015 August 03

2015 July 12

2015 June 24

2015 June 13

2015 April 21

2015 February 23

2015 February 04

2015 January 01