Jump to content

Wikipedia:Reference desk/Archives/Science/2018 November 19

From Wikipedia, the free encyclopedia
Science desk
< November 18 << Oct | November | Dec >> November 20 >
Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


November 19

[edit]

Breaking the Earth

[edit]

How much blow it takes to break the Earth like a pottery? Impact of a Mars-sized world could've easily broke the Earth into pieces therefore we wouldn't be here to discuss this very topic. There's a theoretical weapon as seen in sci fi powerful enough to break the Earth. PlanetStar 03:08, 19 November 2018 (UTC)[reply]

[1]. --Jayron32 03:16, 19 November 2018 (UTC)[reply]
The giant-impact hypothesis says an impact of that size actually happened. The Earth is still here but it would be pretty bad for us if it happens again. PrimeHunter (talk) 03:55, 19 November 2018 (UTC)[reply]
The Earth isn't pottery. On grand scales, a collision between planetary bodies would involve a lot of plastic deformation, much like if the Earth was made of putty. Quite substantial bits might fly off do the force of the explosion, but the bulk would reform itself into a sphere due to gravity. You aren't going to get a pile of large shards, or anything like that. Dragons flight (talk) 11:48, 19 November 2018 (UTC)[reply]
If the Earth where to collide with a planet the size of Earth or a bit larger, then that impact would with high probability be an oblique impact (which means that part of the Earth would be on a trajectory that would miss the target). This would cause the Earth to shatter into pieces. An example is the giant impact that created the Moon, the impactor was completely destroyed. Another example are the large impact basins on the Moon. It has recently been shown that these impacts were caused by impactors that were much larger than the size of the impact basin would suggest, see e.g. here. The reason for the small size of the basin in relation to the impactor is explained by the ratio of the radii of the Moon relative to that of the impactor. The estimated diameter of the Imbrium impactor according to the new study is 250 km, and that makes an impact angle of less than 30 degrees already an oblique impact. When the impactor hits, the shock waves moving through the impactor will cause parts of it to sheer off, but the top part is then going to fly away, missing the Moon. So, a lot of the kinetic energy of the impactor is then lost to space, making it look like the basin was formed by a much smaller impactor. Count Iblis (talk) 03:12, 20 November 2018 (UTC)[reply]
If the planet is big enough it doesn't have to touch it. Move Earth's orbit close enough to Jupiter and it will probably disintegrate into chunks smaller than a few tens or hundreds of miles. Sagittarian Milky Way (talk) 03:59, 20 November 2018 (UTC)[reply]
Indeed, at 54840 km from Jupiter. Count Iblis (talk) 06:13, 20 November 2018 (UTC)[reply]
A couple things. One, planets aren't rigid, so no planet will "shatter" like a piece of pottery. The rock (presumably we're talking about rocky planets) deforms, and some will liquefy. Second, even if you make lots of "pieces", the pieces are still gravitationally attracted to each other. Depending on the physics of the impact, they will re-merge, or some will coalesce into a ring system or one or more satellites, as is hypothesized to have happened to Earth. Totally blasting the planet apart and keeping it that way requires an amount of energy greater than the planet's binding energy, which is titanic, much more than is released in your average planetesimal collision. This generally involves things like giant planets or stars tearing planets apart from tidal forces. This is also more achievable because the energy is not released all at once in a colossal impact, but over time as the planet is gradually yanked apart. --47.146.63.87 (talk) 06:53, 23 November 2018 (UTC)[reply]

Article concerning consciousness and effect of deaths in a random number generator (for real)

[edit]

They placed a generator of random numbers in a slaughterhouse and it started working differently (due to the dead souls affecting it). That is, the slaughtering, the deaths, was causing some sort of field that affected randomness. This is rather a pseudoscience article, with touches of quantum mysticism. Anyway, I'm trying to find it, I do not remember details about the author, affiliation or anything else.--Doroletho (talk) 21:56, 19 November 2018 (UTC)[reply]

Probably [2]. Amazing how people live their lives doing weird things like that. Dmcq (talk) 22:15, 19 November 2018 (UTC)[reply]
Extraordinary Claims Need Extraordinary Evidence. The simplest explanation is that their "random event generator" isn't random. Look at [ http://www.psyleron.com/overview.html ] and note the complete lack of technical details. Now compare the amount of technical detail available at [ http://www.bitbabbler.org/ ], which in my expert opinion is the best random number generator available at any price. Also note the difference in testing; bitbabbler tests with multiple industry standard tests such as Dieharder, NIST 800-22[3] and FIPS 140-2. The scientists who wrote that paper rolled their own tests and ran them on Excel.
They also failed to do a proper control test. They compared days when the slaughterhouse was operating with days when it was closed. A proper control would have the same machinery turned on and the same operators doing the same things they normally do, but without killing any pigs. This would rule out many sources of errors; perhaps a conveyor belt or a cellphone in a worker's pocket emits an electromagnetic signal that affects the output of the "random event generator". The fact that they wrapped it in a mu-metal shield indicates that they know that this is a problem with their design. --Guy Macon (talk) 07:36, 20 November 2018 (UTC)[reply]
Yes of course it is twaddle. And I get especially leery when people look for lagged effects. But it all has a long and interesting pedigree, Frederick II, Holy Roman Emperor is said to have had some prisoners shut up in cask and had a hole in the cask observed to see if the souls could be spotted escaping as they died. Others later tried to weigh people as they died. I'm not sure if the weight should go up because the soul was lighter than material things or down because they had lost the soul. ;-) Dmcq (talk) 11:54, 20 November 2018 (UTC)[reply]
@Dmcq: We do have an article about the 21 grams experiment. TigraanClick here to contact me 12:58, 20 November 2018 (UTC)[reply]
The article on researchgate saturated my bullshit detectors fairly fast. I stopped at the start of the methods section, where they said they procured the random number generator from Psyleron, whose start page (http://psyleron.com/) says in no uncertain terms that their objective is to prove the existence of mind-over-matter influence and the like. That creates an obvious incentive for that company to make faulty products so that "unexplained statistical deviations" occur (because if it does not happen, their marketing target will stop buying their products, in favor of a competitor's that "work"). TigraanClick here to contact me 13:08, 20 November 2018 (UTC)[reply]
Making a true random number generator that is unlikely to be influenced by the external environment is is hard, and making one that has no programmable components that can be compromised is even harder. Look at the http://www.bitbabbler.org/ website for a discussion of some of the challenges. --Guy Macon (talk) 19:13, 20 November 2018 (UTC)[reply]