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  1. 5 points
    scherado has been banned for multiple instances of rule-breaking in his quest to become the Troll King. We apologize that his interruption in the normal rational discourse was all noise and no signal whatsoever. Roger Dynamic Motion has been banned, NOT for incessant hijacking and almost daily irrationality, but for failing to respond to requests for clarity, EVER. Discussion requires that we express our ideas so others can understand. We wish him good luck with his ideas, whatever they were supposed to be.
  2. 4 points
    First off, dark matter and dark energy are two different things and the reasons for expecting their existence are completely unrelated. The only thing they have in common is that they have "dark" in their names. The initial evidence for dark matter came from observations of how stars move in galaxies. Galaxies are formed from stars that are mutually orbiting each other. If we look at a galaxy, and estimate its mass by the matter we can see, we find that there does not appear to be enough to hold the galaxy together. At the speed the stars are orbiting, they should fly apart. We also know how these stars should orbit if the mass is contained to the shape we see it as having. Not only does the galaxy have more mass than that we can see, but the unseen mass must be distributed a lot differently than the part we do not see. For example, in a typical spiral galaxy, a good deal of the mass must be located above and below the disk-like shape we see. If it was made of normal matter, we should see it, if not in the visible spectrum, it should be visible at some other spectrum. This leads us to believe that whatever is causing that extra mass is not made of normal matter, but a type of matter that does not emit or interact with light or any part of the electromagnetic spectrum. Thus the term "dark matter. There have been attempts to explain the discrepancy through developing different models for how gravity behaves, but to date, none have been consistent with all the observations we have made. Dark energy concerns itself with the expansion of the universe. We have known for a long time that the universe is expanding and that distant galaxies are moving away from us. But until couple of decades ago, we assumed that the mutual gravity between the different parts of the universe was slowing this expansion down over time. What we did not know was whether this was enough to eventual stop the expansion all together. In the 1990's a study was made to try to determine if this was the case or not. Basically it worked because as we look at distant galaxies, we are seeing them as they were when the light left them. Thus as we look further away we are looking further into the past. Thus, to explain it simply, by comparing various galaxies' distances to how fast they appear to be receding from us, you can work out how the expansion of the universe has change over time. The surprise came when it was discovered that the universe's expansion was not slowing down, but was speeding up. Not only was it mutual gravity not enough to stop its expansion, but something was overcoming the gravity and pushing the universe apart. They decided to call this unknown influence "dark energy" (mainly because they had already coined the term "dark matter") . We really know very little about dark energy, and the term really just is a place holder for whatever it turns out to be. (Much in the way the terms "X-rays" was coined before we learned that they were just a certain part of the electromagnetic spectrum.)
  3. 4 points
  4. 4 points
    It's just orbital velocity. The only way to transfer rotational energy is through tidal interaction, but this is slow and inefficient. Consider our own Moon. It gains only 4cm per year in orbital height. That's a gain of 1.33e-6 joules per kg per year gained by the Moon. This amount of energy gain in terms of equivalent velocity gain is 0.163 cm/sec per year. And a probe using a planet as a slingshot spends only a relatively short period of time close enough to the planet for this interaction to take place. It is inefficient in that the majority of the rotational energy lost by the planet is given up through waste heat and not transferred to the orbiting body. To explain a gravity slingshot, first imagine the probe some distance to the left of a planet. It is approaching it at 2 km/sec on a trajectory that will follow a parabolic path around the planet, so that some time in the future it will again be the same distance to the left of the planet, but now moving away from the planet to the left at 2 km/sec. Now imagine that this whole arrangement was moving right to left like the planet is orbiting the Sun. the planet's orbital velocity is 4 km/s. So from the sun fixed view, the probe is moving at 2km/ per sec to the left (the relative velocity between probe and planet is still 2km/sec.) the probe whips around the planet as before, and ends up once again moving at 2 km/sec to the right relative to the planet. But now it is moving at 4km/sec + 2km/sec = 6km/sec relative to the Sun. It started out moving at 2 km/sec to the left and ends up moving 6 km/sec to the left. Of course, it doesn't quite gain a total of 4km/sec. Because in the above, we ignored how the planet behaves during all this. It reacts to the gravitational pull between it and probe also, In the first scenario, it would pick up some speed moving to the left as the probe came in from the left, and then start moving to the right as the probe moved away. But since its mass is so large compared to that of the probe, its resultant velocity to the right will be infinitesimal, and in the second scenario, we will see it as an equally small decrease in its right to left orbital speed relative to the Sun.
  5. 4 points
    When Congress created the NEO Search Program in 1998 they tasked NASA with finding 90% of the near-Earth asteroids that are one kilometer or larger. Then in 2005 Congress extended NASA's objective to include 90% of the NEOs larger than 140 meters. While the majority of NEOs have been identified via ground-based telescopes, they are not the only sources. Both WISE and NEOWISE were space-based infrared searches for NEOs before their cryogens were exhausted by 2010. It is a question of size. Since 1998 NASA has discovered ~98% of the NEOs that are one kilometer or larger. The percentage of known NEOs drops according to their size. At 140 meters in diameter fewer than 1% are known. However, while a 140 meter diameter meteorite impact could easily wipe out a large city, it would not cause an extinction level event. What was meant by the asteroid approaching from the "daytime sky" is that the asteroid approached Earth from the direction of the sun. Even with infrared sensing satellites we would not be able to see something approaching Earth from the direction of the sun, unless the satellite was closer to the sun than the NEO. It is our thermal blind-spot. Depending on the density and composition of the NEO, it will need to be between 20 and 25 meters in diameter in order to impact with the surface and form a crater. The Chelyabinsk meteor came very close to impacting the planet and it was estimated to be just over 15 meters in diameter. In order to be the cause of an extinction level event the NEO would have to be very large indeed. The asteroid that impacted the planet ~65 million years ago was estimated to be 12 kilometers in diameter. Currently, the known NEO with the highest probability of impacting Earth is 2010 RF12. Sometime between 2095 and 2117 there is a 5% chance that the asteroid may impact Earth. At only ~7 meters in diameter the NEO does not pose much of a threat. The odds of an unknown NEO causing an extinction level event is extremely unlikely considering the size it would have to be. However, it is only a matter of time before a 50 to 100 meter NEO that we didn't know about impacts the planet and could very possibly kill millions if it impacts a major city. Sources: NEO Search Program - Jet Propulsion Laboratory, Center for Near-Earth Object Studies Sentry: Earth Impact Monitoring - Jet Propulsion Laboratory, Center for Near-Earth Object Studies Absolute Magnitudes of Asteroids and a Revision of Asteroid Albedo Estimates from WISE Thermal Observations - Icarus, Volume 221, Issue 1, September-October 2012, Pages 365-387 (free preprint) The International Astronomical Union Minor Planet Center Asteroid Impact Effects and their Immediate Hazards for Human Populations - Geophysical Research Letters, April 19, 2017 (free preprint)
  6. 4 points
    "Didn't do anything" is incorrect. Obama, for instance, https://www.thoughtco.com/obama-gun-laws-passed-by-congress-3367595 (Trump rescinded an EO limiting access for the mentally ill) Legislation is hard to do when you don't have the cooperation of congress. What would GW Bush and Trump's excuse be on that front?
  7. 4 points
    Bullshit, it's not your precious money to control after it's spent merely because you claimed to have worked for it, princess. It's the government's money. Your receive services from police, fire etc from healthy people, able to work because of a health care system. Yet, police brutality and corruption remains and you say/do nothing about it. The vacuum which is your economic vision of the country is flawed. You drive on roads, camp in parks, visit libraries, churches and museums. I''m not religious, does that mean my money won't be subsidizing those career mooches and purveyors of nonsense any longer? America is more socialist than you say, comrade. You don't want people to have health care, but you want roads paved to move yourself about the country at your whimsy. You want guns and laws to protect YOU from threats, yet "driving while black" (for example) remains a great threat to otherwise hard working, law abiding minorities. I have no kids, but I pay school taxes levied to my property axes.
  8. 3 points
    The danger of inbreeding comes from the fact that it increases the likelihood of the pairing of recessive genes for harmful traits. I'll give you an example. There are two types of Poly-cystic kidney disease. Both are eventually fatal. One, which is carried by a dominant gene doesn't manifest itself until well into adulthood. If you get the gene from either parent, you will get the disease. But since this doesn't occur until you have likely already had offspring, it doesn't get culled from the gene pool. The other type is carried by a recessive gene, and you need to get it from both parents. This version is fatal within a few months of birth. If it is only passed on by one parent, you are just a carrier and you aren't born with the disease. This genetic disorder, while it does prevent the person born with it from furthering the genetic line, remains in the gene pool because it is recessive and can be passed on from generation to generation with the disease itself ever manifesting. This is true of a good many genetic diseases, they hang around because they are recessive traits. Now let's say that thae chance of any given person in the general populace is a carrier of a particular one of these recessive diseases is 1/100,000. Then is is pretty slim odds that two mated people will both have it and low odds that any of their offspring will suffer from the disease. But what if you have a lot of inbreeding within a given family. If that recessive trait exists and is being passed on from generation to generation, the odds of these any two people in this family having the gene is higher than for the general populace and there are higher odds of offspring from a mating between family members of exhibiting the disease. It is not just the paring of identical chromosomes, its the increased likelihood of the pairing of the wrong identical chromosones.
  9. 3 points
    Legally quid pro quo sexual harassment and sexual extortion are both crimes - and unwanted intercourse as a result of both is considered rape, so yes, it is. As for the responsibility to report sexual assault - women have historically and still suffer significant negative consequences when reporting sexual assault, especially by an authority figure: "Despite widespread rape reform laws that have been implemented in this country, victims of rape still face the risk of receiving social stigma should they decide to make their victimization known to authorities" http://journals.sagepub.com/doi/abs/10.1177/0093854893020003003 "A few examples from the DOJ report on Baltimore’s police department: Officers routinely questioned sex crime victims in a way that put the blame on the victims themselves, like suggesting they were responsible. Detectives would ask “Why are you messing up that guy’s life?” and suggest the victims were lying by not reporting the assault immediately. A prosecutor handling a sexual assault case wrote in an email to a BPD officer that the woman who reported the crime was a “conniving little whore,” and the cop responded “Lmao! I feel the same.” Detectives made “minimal to no effort to locate, identify, interrogate, or investigate suspects,” the DOJ said. BPD sex crimes unit officials would complain that all of the sexual assault reports were false, saying at a social event, “In homicide, there are real victims; all our cases are bullshit.”https://assets.documentcloud.org/documents/3009376/BPD-Findings-Report-FINAL.pdf Given the prevalence of this kind of response, both by society and law enforcement to victims of sexual assault, I would say it's rather obvious why a person might not report it, and I think it's pretty disgusting to place any blame on prior victims. The guilty party is the one committing the assault - that should be pretty uncontroversial.
  10. 3 points
    In all fairness, the OP has reached his newcomer temporary post limit and stated that he cannot answer at the moment. (We have seen this before). He also said (several times) that he would answer questions about his wording and hypothesis My only other post here was to take him at his word and ask a simple polite question about one particular aspect of this. I await the response with interest, when he is allowed to post this response.
  11. 3 points
    Video games are far more popular in Japan than the US. Japan had I think two total people killed by guns all last year. Probably more than that will be shot in the US between the time when I began this reply and the time when I hit submit. Likewise, Australia as a culture has the same gruff trailblazing independent strains we have in the US. They pick fights and have brawls and easily do so more than we do. Same result as Japan, though. Next to zero gun deaths. There’s no need to invent reasons here. No need for pretend explanations or unfounded speculation or any mental gymnastics. We’re not more violent than other nations. We don’t play more video games or watch more movies, violent or otherwise. We’re no more predisposed to murder than others. The US is different in only one relevant way from peer nations: Firearm availability.
  12. 3 points
    ! Moderator Note You know what? We're done with your off-topic announcements of childish pique. Feel free to use the Ignore system, but the next time you post about it, YOU. ARE. GONE. Report this note if you want, PM me or another staff member if you like, but don't respond here in-thread.
  13. 3 points
    By comparison this sort of implies Africa as a whole is the worst place on earth. That is debatable and unnecessarily dismissive of Africa as a whole which has nothing to do with this conversation. Opressive regimes, famine, and atrocities exist all over the world; to say that Assad, Kim Jung-un, ISIS, or etc are evil and use them as specific examples for comparison is more appropriate than just casually throwing the whole of Africa and "Islam countries" under the bus generalizing to an insulting degree.
  14. 3 points
    It looks like we were getting bursts of traffic faster than we could start PHP processes, and didn't have enough spare processes. I bumped the maximum number of spare processes up to 25 (from 10) and the overall cap up to 50. I'm not sure if that will solve the entire problem, but it should prevent some of the Bad Gateway errors. Let me know what you experience over the next day or so.
  15. 3 points
    ! Moderator Note First, if swansont (or any mod/admin) is participating in a discussion, he doesn't actively moderate it (with some exceptions in Speculations, where the rules don't require as much judgement). He's not wielding any unfair authority to support his positions. I suspect instead he's using his knowledge of science as a working atomic physicist to support the explanations he uses. ! Moderator Note Second, it's abundantly clear you don't understand much of what you're defending, since you can't support it with evidence or make a testable prediction that anyone studying science could use to verify the accuracy of your claims. Science isn't about finding proof, it's about finding the best natural explanations, which are always the ones that have a preponderance of evidence to support them. Third, you've failed to support your arguments according to the rules of this section. You're also trying to drag our standards down rather than using more rigor to meet them, and that's not what you agreed to when you joined and said you'd follow the rules. If you wanted to test your ideas in a moderated science discussion forum, you shouldn't be pushing back so hard against the constructive criticism. Thread closed.
  16. 3 points
    The thing is when one is in the grip of insanity one doesn't know one is insane.
  17. 3 points
    That's not quite right. Following your logic, there are more than two cards you cannot choose. In fact, there's an infinite amount of them. What about the second to last card? Third to last? Fourth? Etc. That's not quite right either. For example, what are the end points of the set of positive integers? 1 and infinity, right? You cannot identify the last one but you can clearly identify the first. If you want to extend it further and compare it with our case of the cards, imagine if, instead of standing in an undefined point along the line of infinite cards, the cards are placed on the table, stacked on one another, extending into infinity. The first one touching the table can be called the first card, while you cannot find the last one. Obviously, ignore the physical impossibilities of this example.
  18. 3 points
    Pretty much every or any Law is wrong if you give the words meanings that were not intended.
  19. 3 points
    Here you go with the privilege thing again. As though it trumps all other rate payers. So lets put healthcare and roads in the same basket. Most roads are built by fuel taxes and surcharges. Does avoiding taxes by making their own ethanol for their car disqualify a person from using roads? Are passengers freeloading while truckers are paying the lion's share of gas taxes? Doesn't giving a segment of any user group free access while others pay create a culture of dependency in your neoconservative logic? You want (more like adamantly insist) your rights are upheld as assailable, yet exercise broad discretion to deny others who pay into the system. In Canada, right to life ends at death. Family values means if you get sick, we as a country help to make you well so you can return to your family and job. In America, right to life ends at birth and family values means if you get sick, you lose your job, house or children's college fund or die. Good luck with that. And your gratitude for me not having children, is childish if not spitefully ignorant. I gave an example of my procreation history in the context of paying school taxes and even though the mods warned against cheap shots on this very page, you made one anyway. Grow up.
  20. 3 points
    It would help if you quantified this. How many people are beig shot, by what type of weapons, and what regulations are in place preventing firearm sales and are those regulations the same in all the countries? I am not going to waste my morning researching all the data needed by country to analyze your questions when you've provided none to kick off the discussion. With one simple search I found the following and it shows Columbia has just started taking steps to reduce the number of firearms people carry. Seems that obtaining a permit to carry a firearm was rather easy till just last year which implies obtaining firearms was easy as well which counters the assertion that "guns are really hard to get": "Colombia has extended a nationwide ban on carrying firearms until the end of 2016, an attempt to reduce violent deaths at a time the nation is attempting to consolidate peace. On January 19, Colombian President Juan Manuel Santos announced that an executive decree banning carrying firearms in public would continue until the end of this year. The ban was originally in place from December 23, 2015, through January 31. According to BBC Mundo, it is the first time Colombia has implemented a nationwide ban against carrying of weapons. Previous bans have been limited to specific geographic regions, such as certain districts of Bogotá, and were shorter in duration. Santos said the initial December to January restriction had produced positive results towards reducing homicides, saving many lives. During this period, Colombian Minister of Defense Luis Carlos Villegas said homicides fell 13 percent when compared to the same period in 2015. Hoping to usher in an era where disputes are resolved peacefully, Villegas said the 2016 weapons restriction is intended to address two problems. The first is homicides resulting from arguments and committed using a firearm. Colombia has issued 500,000 carry permits for firearms and another 400,000 possession permits; meaning roughly one in 53 citizens has a weapons permit. Santos' decree reverts all carry permits to possession permits, meaning firearms can no longer be carried in public except in certain cases. " http://www.insightcrime.org/news-briefs/colombia-implements-ban-against-carrying-guns-2016
  21. 2 points
    I think I repeated this already a few times. Philosophy is the investigation in our way of thinking. Capra is the godfather of new age kitsch of physics, especially of QM, comparing insights of physics with 'eastern wisdom'. So yes, such kind of books. Is physics not also a kind of knowledge? Note I use 'e.g.', i.e. physics as an example of knowledge. You said this: You suggest here science only provides experimental and observable facts, and that the theorising is the task of philosophy. Can you elaborate? Can you give some example of 'knowledge', that then is interpreted by philosophy? Where does that leave theory building? Well, this is the bon mot by Russell: We still have no idea what dark matter is. Should we ask philosophers? I am pretty sure we should not. Let physicists and cosmologists try to find out. It is an empirical question, so it is a scientific question. OK, I took the effort to find out in what context Russell said this. It comes from 'Unpopular essays', Chapter 'Philosophy for laymen', page 24 (here a link where you can download it as pdf) It stands in the context of the idea that all of science was called 'philosophy' in antiquity and the middle ages, and that at the moment parts of it became empirically based theories they became science. Of course this feeds the idea that in the end nothing is left for philosophy. But pity enough this has nothing to do what philosophers are doing today. So you cannot apply Russell's use (in a historical context) to the present situation. And Russel is definitely positive about philosophy (page 33)
  22. 2 points
    First and foremost you need to understand that both "Dark Matter" and "Dark Energy" are merely placeholders, or labels, for something that we do not understand. It does not mean that either are "dark." They are only "dark" because we do not understand either. So they are really a description of our ignorance than anything real. As Janus correctly pointed out, Dark Matter and Dark Energy are completely unrelated. Dark Matter's history goes back to the 1930s. Fritz Zwicky first discovered the unusual rotational periods while working on galaxy clusters. It went largely unnoticed until the 1970s when Vera Rubin began studying galactic rotation. For some unexplained reason, galaxies were rotating far faster than they should be for the amount of visible matter that they have. Galaxies were rotating as if they had considerably more mass, mass that did not react to light. Hence the term "Dark Matter" was created to label this invisible matter. Since the late 1970s there has been a search for this missing matter. We can identify the effects Dark Matter has, such as the rotation of the galaxies, and also gravitational effects that causes light to bend, but we are no closer to identifying what Dark Matter actually is. There have been lots of theories, from Massive Compact Halo Objects (MACHOS) to Weakly Interacting Massive Particles (WIMPS), but so far none of them have panned out. In the case of Dark Matter we have something tangible and observable that we have not yet been able to explain. We have even made maps of Dark Matter using the light as it bends passing through such a strong gravitational field. We just can't see it, or explain what it is. Dark Energy, on the other hand, is something completely different. The term "Dark Energy" came along in the 1990s in an attempt to explain why the universe was not just expanding, but accelerating. Vesto Slipher first discovered galactic red-shifts in 1912, but it took Edwin Hubble to correlate these red-shifts into distance. While not a very accurate means of determining distance, it was sufficient to identify that galaxies were moving away from each other, and the further away they were the faster they appeared to be moving. In 1927 Georges Lemaitre, using Einstein's 1915 Theory of General Relativity, came up with his "Primordial Atom", which would be latter derisively referred to as the "Big Bang" by its biggest critic, Fred Hoyle. This debate on whether the universe was static and everlasting or had a beginning continued until 1964. When the cosmic background radiation was detected in 1964 it was the crucial evidence needed to sway the majority of astronomers and astrophysicists to accept the "Big Bang." Numerous attempts have been made to determine the age of the universe, beginning with Edwin Hubble. Unfortunately Hubble's initial estimate at the rate the universe was expanding (also known as the "Hubble Constant" today) was 500 km/s/Mpc or about 153 km per second per million light-years, which gave him an estimate of ~2 billion years. Hubble's mistake was his use of Cepheid variables as a "Standard Candle." We have since substituted Type Ia Supernovae (SN) to be our new "Standard Candle" and the current age of the universe (13.813± 0.038 billion years), making the Hubble Constant 67.31± 0.96 km/s/Mpc or ~20.65 km per second per million light-years. This is also where "Dark Energy" first makes its appearance. During the 1990s a concerted effort was made to record as many Type Ia SN as possible, and when the distances to these Type Ia SN were measured they concluded that the universe is not just expanding (as Hubble noted), but accelerating. Unable to explain this acceleration they attributed it to some unseen, and before now, undetected form of energy which they labeled "Dark Energy." Since that label was created we have since discovered that Type Ia SN are not the "Standard Candle" astronomers originally presumed them to be. Originally it was assumed that all Type Ia SN had an absolute magnitude of -19.46. However, in 2006 we discovered the first of several "superluminous" Type Ia SN. Then in 2013 a whole new classification of supernovae was created. This new classification, Type Iax SN, had an absolute magnitude ranging between -14.2 and -18.9, much dimmer than Type Ia SN. Furthermore, it is estimated that between 18% and 48% of all the Type Ia SN prior to 2013 have been misclassified and should actually be Type Iax SN. Which calls into question the Type Ia SN data collected during the 1990s used to calculate the age of the universe and its alleged acceleration. Exactly like Hubble's mistake using Cepheid variables as his "Standard Candle" in 1927 to determine the age of the universe, our understanding of "Dark Energy" could be attributed to the Type Ia SN we also mistakenly thought was a "Standard Candle" in the 1990s. We can distinguish the difference between Type Ia SN and Type Iax SN with sufficient data, but identifying "superluminous" Type Ia SN and distinguishing them from normal Type Ia SN is another matter entirely. Which means that there is no such thing as a "Standard Candle" in astronomy. Sources: A History of Dark Matter - arXiv : 1605.04909v2, May 24, 2016 WIMPs & MACHOs - Encyclopedia of Astronomy & Astrophysics, 2002 [PDF] A Brief History of Dark Energy - Astrophysics & Space Science, Volume 319, Issue 1, January 2009 (free preprint) What is the Hubble Constant? - Space.com, March 21, 2014 Type Iax Supernovae: A New Class of Stellar Explosion - The Astronomical Journal, Volume 767, Number 1, March 25, 2013 A Comparative Study of the Absolute Magnitude Distributions of Supernovae - The Astronomical Journal, Volume 123, Number 2, 2002
  23. 2 points
    I'll answer your question: I havn't a bloody clue, OK? Now let me add some further comments....when we (the forum) suddenly has a newbie popping in asking a question with obviously a giant ego to feed, and when that newbie when requested for clarification of his questions by not one, but many reputable members, who are known as credentialed authorities in the discipline being discussed, answers with total arrogance and dismissal of those clarifications and requests, then in my mind that newbie needs to take a backward step, have a disprin, and a good lay down and start thinking as to why so many knowledgable members are making there requests. Otherwise other members observing such egotistical arrogant behavour from that newbie, will just dismiss him as another f$%#^&$# troll that science forums such as this seem to attract. I hope that helps.
  24. 2 points
    What makes you think you're right?
  25. 2 points
    If you have had to say it more than once, it's clear that you should, indeed, clarify your post.
  26. 2 points
    Well, it is true that there were no words in your post that cannotbe found in a dictionary, the combination of some of those words is unusual in physics. Consider, as an example, your phrase " convergent counter-spatial centripetal charge". If this were a common, or even occassional physics phrase, then we might expect to find some examples on Google Scholar. But there are none. What about dropping one word: "counter-spatial centripetal charge"? No luck. Finally, when we get down to "centripetal charge" Google scholar returns three hits. That's 3 hits. In contrast, if we choose a phrase like centripetal acceleration we get 18,500 hits. That's eighteen thousand five hundred. If physicists are not using such phrases and you are discussing physics, perhaps you should try a change of terminology. If you think it is sufficient to let other terms "speak for themselves" then you haven't been paying attention to the way science has been reported for the last century or two. I thought I might try and throw you a life-line, so I looked for your phrase on DuckDuckGo. Success! Four, that's 4, hits! The trouble is they were all made by you. You might want to take the advice of swansont, a practicing physicist - use the language of the science correctly.
  27. 2 points
    Exactly. The OP can be likened to complaining about paying taxes for bridges because people are too lazy to swim or too cheap to buy a boat.
  28. 2 points
    I just killed some idle processes on the server and upped the PHP opcode cache memory limit to 128MB instead of 64MB (it was full). Both should help a bit. I'll check in again tomorrow to see if the memory limit is adequate and see if there's anything more I can do.
  29. 2 points
    Don't worry about it scherado. Just ignore him.
  30. 2 points
    This is an international forum and as much as you'd like to believe it, it's not the constitution of the free world. It's an archaic document violently achieved in protest of the crown (how ironic is that). Once again, iterating the false narrative that ANTIFA is inherently violent, therefore all liberals are inherently violent. Trump tried that and failed, as do you. Doubling down only makes it twice as absurd. Is there no abyss too deep to stoop? A lot of outsiders are looking in as Americans pit themselves against each other in ridiculous, hypocritical, contentious and often deadly ways. For lack of a better analogy, your constitution is being perverted in the same manner the jihad perverts the Quran. Liberal, conservative... who cares, y'all look the same to me (to use a common American meme about others). Free speech and freedom of the press are the cornerstones of your constitutional 1st Amendment, while your unhinged leader disrespects both on a daily basis as policy. Even calling for the persecution of those who lawfully protest his actions, yet nary a peep from the malcontent that so loudly claims to be a rigid constitutionalist. Heaven forbid had Obama done that, you'd be screaming impeachment from the rooftops and rounding up your 2nd Amendment buddies, huh? Well, maybe that's a little extreme and don't proclaim it hasn't been said by others, but definitely chanting "Lock him up", right?
  31. 2 points
    Today is the s***iest day of the semester. I got the assignment of writing an interpretative essay on War and Peace by Leo Tolstoy. So raising the question: Why is this "necessary" for a chemistry degree? What do I learn from it? Better writing skills? No. I have no need to "perfect" my writing skills because I can write perfectly well already. The degree of "Writing perfection" that schools demand is preposterous and frankly whoever thought "Let's make students who don't give a flaming flying pigs**t about perfecting their writing write long essays that have been written millions of different ways for no intensive purpose whatsoever" should be drawn and quartered if they are still alive. This wastes my time, I could be researching kinds of cytokines and biochemistry applications to begin to fathom a way to carve out a living for myself. But no, you get War and Peace. Why do I need to "prove myself"? Why are people wasting my time by force feeding me laborious literature when I've proven I'm not a useless idiot? And to what end, what do they hope to accomplish? Education comes through curiosity about the world and how it works, that's why I was obsessed with radiation and nuclear weaponry and power applications at age 7, when I first picked up a book called Great disasters of history and saw the mushroom cloud from Castle Bravo and the terrible effects of the radiation wrought by Chernobyl. The inability of the educational system to recognize proficiency and deficiency in students will be the end of me, not everyone is equal intellectually, as not everyone has an IQ of 60 or an IQ of 230. I can see continual mathematics because it is a linear field, but there is excess writing, excess moral study, and not enough actual history, and not enough scientific exposure.
  32. 2 points
    Disconcerting even when viewed per capita / controlled for population: https://www.vox.com/policy-and-politics/2017/10/2/16399418/us-gun-violence-statistics-maps-charts
  33. 2 points
    For God's sake, don't ask us! Ask your dissertation director. It is the people who will be reviewing your dissertation that count! Generally speaking, while a master's thesis can be a "review" of other work, a doctoral dissertation must be original work- but that original work can extend previous work by others.
  34. 2 points
    The trick is to get something cooler than the dew point of the surrounding air so that moisture in the air condenses on the surface in a manner that it can then be collected. MigL's suggestion does all that (it can be as simple as a piece of plastic stretched between, say, four rocks weighted down by four more with a small pebble sitting in the middle to get a bit of slope, and a cup underneath the lowest point to catch the accumulating water.
  35. 2 points
    The title asks when; honest answer is no time in the foreseeable future. While adoration for guns alone isn't a good excuse it is the one tens of millions ardently feel/use. There is no good reason for believing man has only existed for 10,000 years or that there was a global flood yet people have faith in that stuff anyway. Ultimately passion defies reason. People have accepted amongst themselves in a tribal manner that the their heritage and the very notion of liberty itself is fundamentally associated with unrestricted access to guns. I makes no f#$&'in sense to me but is the case none the less.
  36. 2 points
    Probably best to at least wait until the second date before asking about butt stuff, though
  37. 2 points
    You can create entangled electrons by splitting a cooper pair. The electrons in a pair are not necessarily close together; because the interaction is long range, paired electrons may still be many hundreds of nanometers apart. This distance is usually greater than the average interelectron distance, so many Cooper pairs can occupy the same space. Electrons have spin 1/2, so they are fermions, but the total spin of a Cooper pair is integer (0 or 1) so it is a composite boson. Many hundreds of nanometers is not a large distance tough https://en.wikipedia.org/wiki/Cooper_pair https://arxiv.org/pdf/1205.2455.pdf
  38. 2 points
    Handmaiden to matter is not particularly revealing. Yes, they are arbitrary. So are the rest of our units — the meter, the coulomb, etc. What of it?
  39. 2 points
  40. 2 points
    Not really... Agape is an unconditional love for all beings, whereas eros is sexual love, so totally different. The family/brotherly love of philia is also very different to the other 2. It isn't just the recipient that is different - it is a different 'feeling' or emotion that is experienced - thus the different words, which have their own definitions.
  41. 2 points
    When you get close to making a decision please let us know.
  42. 2 points
    I'm not sure I understand the distinction. However, as noted previously, the duration (not time) is determined by looking at the current rate of expansion (e.g. how the distance of galaxies increases with time duration) and the current temperature of the CMB radiation (and therefore how much it has cooled in the time duration since recombination). We can trace the evolution of the universe over time duration back to a much earlier time point (our current physical theories no longer earlier than that time point). And so we know that there is a time duration of about 360,000 years from the earliest time point we can model to the time point when recombination happened. But I am curious as to why you say it is impossible to know this? Is that based on a flaw in the physics? Or a philosophical/religious belief? Or ... ? Disappointed that you are not willing to share your knowledge. How, exactly, will I make this determination?
  43. 2 points
    Absorbed. (adsorption is a different effect. Light will never be adsorbed.)
  44. 2 points
  45. 2 points
    Protip: Stop using the word "energy" to describe what you're feeling. It makes the idea look like nonsense. It's quite possible there's a real effect happening here. Encourage you to learn the technical language well enough to research and describe it accurately so your ideas are taken seriously.
  46. 2 points
    There seems to be confusion between the 'observable universe' and 'universal domains'. A domain is a volume of the universe, originally in causal contact, for which quantum fluctuations of the vacuum energy triggered inflation, and subsequent symmetry breaks, at different 'times' and in different ways. These domains would be separate from each other and may have different physical laws. IIRC they would be characterized by magnetic monopole production at the domain boundaries . And they are purely speculative as they would lie outside our observable universe. The observable universe, as Mordred has pointed out, is a causality sphere, and is different for each observer. It is a mathematical construct, defined by the distance light/information could have travelled to reach the observer since the Big Bang. In effect, the person standing a meter to your left, has a different observable universe than you; His extends a meter farther to the left, and is a meter shorter to the right. So when Strange says there could be an infinite number of observable universes in a finite universe, if space isn't quantized, that means the universe can be infinitely subdivided into different observable portions, as each will always be different.
  47. 2 points
    The challenge with your question is we must make certain assumptions about the global political response. Before we can model the possible future, we must start by making decisions about humans will change their behaviors (and predictions are hard, especially about the future!). The answer will be extremely different if we stop polluting 100% immediately than it will be if we gradually stop polluting over the next 100 or 1,000 years or if we don't change at all. Note that I include CO2 in my use of the word "pollution," but intend to refer to more than just that. Earth has survived massive comet impacts, extreme volcanic and seismic activity, has gone through ice ages and solar storms and hosted vast epochs of life and change and much more. The earth will be fine. It's us and the other life on it that could be in trouble. Some useful information and helpful links available for you to explore here: https://www.skepticalscience.com/co2-pollutant-advanced.htm
  48. 2 points
    I would say the direct connection is momentum. The forces are equal (an opposite) and the time of interaction is the same, so the impulse on each is the same magnitude.
  49. 2 points
    But the whole point is that Itoero claimed mass is not conserved "because it is information". Which is clearly wrong.
  50. 2 points
    It's very much the point, it's all about interpretation (how many variations of the same text in that link) and understanding the culture of the writers. Imagine it was written in WWII, by either side, collaboration with the enemy would be frowned upon but that doesn't mean I can't have German friends now.