Wikipedia:Reference desk/Archives/Science/2015 February 13
Science desk | ||
---|---|---|
< February 12 | << Jan | February | Mar >> | February 14 > |
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. |
February 13
editShrinking atom
editI was briefly reading some arguments as to why an atom cannot be shrinking. But the most common one: electrons are point particles seems to be the most compelling evidence that atoms are shrinking. The subatomic particles are not shrinking as they can't since they are in fact true point particles. So what is shrinking is the distance among the various subatomic point particles. Since they are infinitely small they should be able to get infinitely close without ever touching. Right?73.160.39.193 (talk) 04:43, 13 February 2015 (UTC)
- They aren't really particles at all, at least most of the time, when they behave more as wave probability functions. That is, they have no definite position. In the case of a black hole's gravitational singularity, the atoms do theoretically shrink into an infinitely small space (all of the atoms shrink into the same infinitely small point). StuRat (talk) 05:57, 13 February 2015 (UTC)
I don't see how what you say relates to my question.2601:C:3600:46B:5D02:835C:3D28:D9CE (talk) 06:57, 13 February 2015 (UTC)
- We don't know what you have been reading, but you might like to try our articles on Atomic structure, Pauli exclusion principle and Atomic orbital, all of which suggest that the answer to your question is "wrong". I wonder if you are thinking of "metric" in the sense of atomic distances and thinking that this might be shrinking? The word "metric" in the confusing article title Metric expansion of space refers to the Friedmann–Lemaître–Robertson–Walker metric. Dbfirs 07:42, 13 February 2015 (UTC)
- It might help in answering your question if you could explain why you think that atoms can/should shrink in the first place. The size of a hydrogen atom is basically set by the uncertainty principle, the electron mass, and the strength of the electromagnetic interaction. The first of those is too fundamental to change. The variation of the other two over the last few billion years is known to be small and is consistent with zero (see Fine-structure constant#Past rate of change, though it seems to imply there's convincing evidence for a nonzero variation, which I think is not the case). -- BenRG (talk) 10:03, 13 February 2015 (UTC)
- I suspect the OP is referring to the "alternate" theory to the big bang, that space is not expanding, but that matter is shrinking. This has been discussed before in the archives. μηδείς (talk) 20:54, 13 February 2015 (UTC)
pulmonary function test
editwhere can i find information on this test and the application of its steps. — Preceding unsigned comment added by 71.46.193.85 (talk) 04:43, 13 February 2015 (UTC)
- Do you mean the test where you blow into a tube and try to get the balls to rise as far as possible ? Or do you mean the test where they measure blood oxygen levels while the subject exercises ? Or some other test ? StuRat (talk) 05:59, 13 February 2015 (UTC)
See:here where the different tests are explained. Richerman (talk) 14:34, 13 February 2015 (UTC)
A quantum leap (jump) in the state of quantum equilibrium (balance) of the Law of conservation of energy
edit1) Did a quantum leap (jump) been in the state of quantum equilibrium (balance) of the Law of conservation of energy, that is be, could be the acceleration of quantum doing a quantum work in the state of quantum equilibrium (balance) of the Law of conservation of energy?--83.237.222.238 (talk) 10:25, 13 February 2015 (UTC)
2) May be quantum physics is been a special particular case of nuclear physics?--83.237.223.234 (talk) 11:18, 13 February 2015 (UTC)
- Is been you Alex Sazonov? Dbfirs 12:34, 13 February 2015 (UTC)
- I'm using perfect.--83.237.196.190 (talk) 13:30, 13 February 2015 (UTC)
- Stappers will get you. Or be you Slandeutch? {The poster formerly known as 87.81.230.105} 212.95.237.92 (talk) 14:31, 13 February 2015 (UTC)
- I'm using perfect.--83.237.196.190 (talk) 13:30, 13 February 2015 (UTC)
3) If in nuclear physics a work of acceleration of electron is always creating the output of energy, why did in quantum physics a work of acceleration of quantum did not creating the output of energy, is it be because the same and one electron been in a different physical state of the environment?--83.237.214.35 (talk) 14:16, 13 February 2015 (UTC)
- 2) Nuclear physics is defined in terms of the topic of study. Quantum mechanics is defined by the scale of the subject, and also by the type of math used. Sometimes, people use QM to study nuclear physics, sometimes they don't. From the first article: "A heavy nucleus can contain hundreds of nucleons which means that with some approximation it can be treated as a classical system, rather than a quantum-mechanical one." SemanticMantis (talk) 14:19, 13 February 2015 (UTC)
- Thanks! I believe, that nuclear physics is been the physics of the ideal case – physics of ideal model, but quantum physics is not been same.--83.237.211.80 (talk) 14:34, 13 February 2015 (UTC)
- Energy in nature in its pure forms did not existed (existing), the energy in nature always been existing in the forms of work!--83.237.245.203 (talk) 16:21, 15 February 2015 (UTC)
- Thanks! I believe, that nuclear physics is been the physics of the ideal case – physics of ideal model, but quantum physics is not been same.--83.237.211.80 (talk) 14:34, 13 February 2015 (UTC)
Self-esteem and its relationship with narcissism.
editDo people with high self-esteem tend to develop narcissism later in life, as Penn & Teller claimed in 2010? Thanks in advance. --Ann (talk) 16:57, 13 February 2015 (UTC)
- I tend to think of self-esteem as relating more to superego ("I'm a good person !") and confidence ("I can accomplish anything !") and narcissism more to the ego ("Everybody wishes they were me !") and superficial qualities ("I am the prettiest/handsomest person and I have the most fashionable clothes, car, and house !"). So, I don't think they are directly related. StuRat (talk)
- Egocentrism be better than a guilt complex in front of everyone! In my understanding, in christened Christians had been always living the Christian God, but not Proud - Satan, and even more so that the Lord God did not had the Sin in Self - pride and narcissism.--83.237.244.154 (talk) 18:16, 13 February 2015 (UTC)
- Hi again, Alex. Is Moscow cold at this time of year? Are you using Google to translate from Russian? Dbfirs 19:20, 13 February 2015 (UTC)
- Now-now, you don't have to get personal with the poster. It should be sufficient to ask, "What the bloody L are you talking about?" ←Baseball Bugs What's up, Doc? carrots→ 01:16, 14 February 2015 (UTC)
- Even if Jesus Christ is not be the Lord God, he also had the Christian Christening!--85.141.239.49 (talk) 03:59, 14 February 2015 (UTC)
- Now-now, you don't have to get personal with the poster. It should be sufficient to ask, "What the bloody L are you talking about?" ←Baseball Bugs What's up, Doc? carrots→ 01:16, 14 February 2015 (UTC)
- Hi again, Alex. Is Moscow cold at this time of year? Are you using Google to translate from Russian? Dbfirs 19:20, 13 February 2015 (UTC)
Edit: I should mention that I am primarily interested in scientific data that proves or disproves the aforesaid claim. Nonetheless I thank both of you for your replies. --Ann (talk) 18:40, 13 February 2015 (UTC)
- I doubt if you'll have much luck with that, since personality traits are really just matters of opinion. There could be a study based on surveys, but that's just aggregated opinions. StuRat (talk) 19:57, 13 February 2015 (UTC)
- That having an ego means one thinks "Everybody wishes they were me !" is one such opinion. We all have an ego, but most of us don't think like that, Stu. Quote from Id, ego and super-ego#Ego: The ego is the organized part of the personality structure that includes defensive, perceptual, intellectual-cognitive, and executive functions. Conscious awareness resides in the ego, although not all of the operations of the ego are conscious. -- Jack of Oz [pleasantries] 22:00, 13 February 2015 (UTC)
- Well, I wanted to give a quick summary of the differences without explaining all the various conceptions of ego from various philosophers, and without them having to read it in all of our related articles, either. StuRat (talk) 23:37, 13 February 2015 (UTC)
- Maybe a noble aim, except your quick summary of the ego is nothing like its accepted meaning. What you gave is closer to an example of narcissism than to the ego. -- Jack of Oz [pleasantries] 04:16, 14 February 2015 (UTC)
- Well, I wanted to give a quick summary of the differences without explaining all the various conceptions of ego from various philosophers, and without them having to read it in all of our related articles, either. StuRat (talk) 23:37, 13 February 2015 (UTC)
- The article Narcissistic personality disorder has the following quote: "A nationwide study in the United States found that 7.7 percent of men and 4.8 percent of women could be diagnosed with narcissistic personality disorder (Stinson et al., 2008). These data also suggest that narcissistic personality disorder is more prevalent among younger adults, possibly supporting the impression that narcissistic personality disorder is on the rise as a result of social and economic conditions that support more extreme versions of self-focused individualism (Bender, 2012)." Its not clear from this whether "self-focused individualism" entails higher self-esteem, but it's possible. The reference link for this is gone, but Donna S Bender published this [1] article in 2012 on the issues. --Modocc (talk) 22:53, 13 February 2015 (UTC)
- I think as time goes on and a the high self esteem is incubated with a lot of luck and pomp and circumstance then it can easily "fall" into the narcissistic because the person has no other reality or truth than the things you were saying a narcissist says. Like everyone wants to be me because most likely everyone does. Based primary on their good luck. 2601:C:3600:46B:1D31:3204:FBD:A795 (talk) 01:47, 16 February 2015 (UTC)
Is there any reliable evidence of different CD players differing in audio quality?
editOf course, I mean stand-alone players. And by "evidence", I mean double-blind trials. I am aware that some audiophiles disparage double-blind studies, but I'm not sure why. If there is evidence of difference, what factors matter?--Leon (talk) 20:09, 13 February 2015 (UTC)
- CD systems and stereos may intentionally apply audio equalization, according to the preferences of the manufacturer. This means that the audio signal that goes out of the box is not intended to be a waveform-accurate, perfect recreation of the original waveform that was losslessly recorded in the digital medium.
- Depending on the nature of that type of post-processing, it's completely plausible that the sound quality can differ between makes and models.
- For example, here's an application note (colored by a little marketing-ese) on the use of Analog Devices Blackfin DSPs to post-process audio signals in a consumer-grade stereo system. The entire purpose of that DSP is to intentionally distort the waveform, not to perfectly recreate it. The objective is to improve quality, but whether that goal is accomplished is subjective. Nimur (talk) 20:27, 13 February 2015 (UTC)
- By "stand-alone players" you are presumably excluding the speakers, as obviously those will vary in quality from device to device. StuRat (talk) 21:22, 13 February 2015 (UTC)
- Yes apparently that is obvious to the tiniest mind. The well phrased question did not leave that open to doubt. As to the question, there are different D to A strategies (I doubt these are audible), and then there are different error correction strategies (could easily be audible), and then there are different manipulations applied to the analog signal. Different CD players will have different amounts and spectra of crosstalk and noise in their analog stages. So i'd say yes, it is quite likely that some people could reliably identify a particular CD player in an ABX test, on some CDs.
- There is no doubt that not all modern audio systems are perfect...and perhaps some audiophiles can tell the difference. But there are two things at issue here - most people like the audio to be deliberately tweaked compared to 'reality' so very often, it's a matter of personal preference rather than some measurable "quality" metric. The deeper problem is that audophiles are a sad, sad bunch of people. They used to have a hobby like those of many geeks where they could become totally immersed in a deep technical subject and become experts - then they could argue with each other about the merits of this amplifier with that turntable with this special zirconium-tipped stylus or whatever. They had a GREAT hobby. Then along came CD's and digital audio and sound reproduction became (by far) better than the human ear can possibly detect. Overnight, their expertise is blown away. A $100 sound system performs pretty much as well as at $10,000 sound system...and everything they knew about analog audio became irrelevent.
- Some of those people turned to other subjects and became computer geeks or video geeks or car geeks. But a few persist in their claims to be able to detect the most subtle imaginable differences, then claiming this or that cause. They dislike double-blind tests simply because they conclusively prove that all of these people are talking utter, utter bullshit. They don't want to hear that because they've invested so much of their very souls into this subject.
- If you ever doubt this, just take a look at this $10,000 ethernet cable...which any non-audiophile will tell you will perform PRECISELY identically to these cables which cost $12 for a pack of 5. This is just insanity. Double-blind listening tests would demolish this claim in a heartbeat.
- Now, the unfortunate part about this is that it is remotely possible that the different quality of A-to-D converters might make a difference in the sound quality of one CD player versus another. But because of this audiophile madness, you simply cannot trust a single word they say...anyone who will claim to hear the difference in sound quality between a purely digital signal streamed over a $10,000 ethernet cable versus a $3 cable simply cannot be trusted to tell you the difference between a $20 and a $30 CD player. Even if there is a difference - the choice between one and the other is likely to be hotly debated and largely a matter of personal preference anyway.
Why did my cat meow at a youtube clip about a giraffe tossed from a space station?
edit
My cat went meow when she saw this clip from Soyuz rendezvous and docking explained . Were a cosmonaut launches a giraffe... There appears to be a 'I love Russia' ideogram where not even a made in china label ought to be – but it is out of focus by the time it comes into view so not easy to say. Is this supposed to be a subtle subliminal message due to its juxtaposition or propriety gone wrong? Every gram costs money to send into obit.--Aspro (talk) 21:40, 13 February 2015 (UTC)
- I don't know what, but it might be a label identifying whatever lies inside the giraffe that the fabric is protecting. Or maybe weight is not a premium because it's a demo shot from within a plane in freefall? Or, as you suggest, it's just simply a fun propaganda toy, and I like this explanation the best, :-) BTW, thus far, my searches for images of the label or ideogram hasn't turned up anything like it. -Modocc (talk) 23:04, 13 February 2015 (UTC)
- Isn't it simply the Ty Inc. logo? That Beanie Baby appears to be called "Giraffiti", which was taken into space on Soyuz TMA-13M (ref) -- Finlay McWalterᚠTalk 23:40, 13 February 2015 (UTC)
- Was there an animal sound on the soundtrack? That's more likely to make a cat react than a random image. ←Baseball Bugs What's up, Doc? carrots→ 01:12, 14 February 2015 (UTC)
- Funny now that I play the clip again that the label appears much clearer than earlier when it was fuzzy. Does youtube radically change/adjust the resolution of the video it streams? Or am I just imagining things and I am preconditioned now to recognize what is obviously the Ty label? On second thought, the variance could very well be due to my macular degeneration. --Modocc (talk) 04:46, 14 February 2015 (UTC)
- It take it you don't live in my part of Europe, where we feel that we have lost the Cold War, since all the rich Russian oligarchs are over here buying up real-estate and everything else – like money is going out of fashion. This is an example of such an ideogram: [2]. Bears a remarkable resemblance to that covering the giraffe's κωλοτρυπίδα don't you think? --Aspro (talk) 14:19, 14 February 2015 (UTC)