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  1. 7 points
    OK let's clarify something here. First consider the following definitions. Mass is resistance to inertia change Energy the ability to perform work. Spacetime a geometric model system with 3 spatial dimensions with 1 time dimension. In physics dimension is an independent variable or value that can change without affecting any other mathematical object. So how does mass curve spacetime. Well GR models bodies in free fall that is without any force applied. Time is given units of length and can be called an interval. This is done by setting c which is constant to all observers and adding a unit of time. So the time coordinate is given units of length by ct. [latex] (t,x,y,z)=(ct,x,y,z)=(x^1,x^2x^3x,x^4)[/latex] the last is in four momentum form for convenience as its useful to model a particle trajectory along the x axis. Now what is spacetime curvature. Well space is just volume... (Very important ) it isn't a stretchable bendable fabric... Those are just analogy descriptive. What spacetime truly means by curvature is the worldline paths for light it us the null geodesic. If you shoot two laser beams in flat spacetime those beams stay parallel. If spacetime is curved then the beams converge for positive curvature and spread apart for negative curvature. This is a consequence of how the mass term affects the time it takes for a particle to go from emitter to observer. That whole resistance to inertia. So let's drop two objects toward a planet. You have the usual Centre of mass. As the objects free fall they do not stay parallel. They will converge upon one another as they approach the center of mass. That what is really meant by curvature the free fall paths are curved. Not the volume of space.
  2. 6 points
    Right, he is saying that the speed of light in both directions is the same with respect to any inertial frame as measured from that frame. So in the following example we have two observers. One standing along the tracks and the other traveling along the tracks in a railway car. Two flashes are emitted from two points along the tracks that are equal distance from the track observer. the light from these flashes arrive at the midpoint observer at the same moment as the railway observer is passing him. Thus both observers detect the light from the flashes at the same time. Like this: For the midpoint observer ( or anyone at rest with respect to the tracks) these flashes were emitted simultaneously, as shown by the expanding circles: However, for the railway car observer, events have to occur differently. He still detects the light from both flashes simultaneously, and they arrive when he is adjacent to the track observer. But unlike the track observer he has not remained halfway between the emission points the entire time. He is not an equal distance from the emission points when either of the flashes was emitted. But he must also measure the speed of light for each of the flashes as being the same relative to himself. But since the distances each of these flashes travel relative to him are not the same, in order for the light of the flashes to reach him simultaneously, they must have left at different times. And the sequence of the events for him occur like this: For the track observer, the flashes are emitted simultaneously, but for the railway observer they are not. This is the relativity of simultaneity: Events that are simultaneous in one inertial frame are not so according to another which in relative motion with respect to the first frame.
  3. 5 points
    Brevity and sarcasm. No wonder no-one knows WTF you're talking about half the time.
  4. 5 points
    Hello everyone! It has been a while since I was active in the forum. Sure, I post a song here and there, but I just can't participate like I used to. I'm still having problems with my left hip even though I had a hip replacement back in April, 2017. Since then, I lost my job and medical insurance because I simply can't sit and write code for hours on end due to the extreme pain in my left hip. I lost my job as a software engineer in the middle of being treated by my doctor and they want a $500 deposit to continue treating me. Unfortunately, I don't have any income, I'm unable to work, and I've blown through my savings on living expenses and doctor bills. Most likely, I will need a revision done on my hip replacement to fix whatever is wrong so that I can go back to work and be a productive member of society. So, I'm reaching out to the community and asking for your help! The following link is to my GoFundMe campaign. I've attached photos of how my surgeries went so you will understand how much pain I'm actually experiencing. It's ok if you can't donate. You can help me out tremendously just by sharing this link! Every little bit helps!!! https://www.gofundme.com/clevelandraymond Thank you all so much! I truly appreciate anything you can do. Not only does your efforts mean the world to me, but also to my family as well.
  5. 5 points
    People are starting to argue with reputation points. I see more and more negatives, on both sides, even for valid points which deserve deliberation. It is a very sensitive subject but, I have come to know that everyone involved in this discussion is a sensible person. Discussion leads to understanding, so if you want your viewpoint understood, discuss it. Don't neg rep opposing views, they're just trying to make their viewpoint understood.
  6. 4 points
    They have nothing in common because you have chosen two different lines (with different values of m and b). As a real mathematician would know, if we have a single straight line, we cannot determine the value of m and b from a single pair of x and y values. However, if we have two pairs of x and y values then we can solve for m and b. One simple way of calculating b is to set x to zero. And then the value of b is just the y-intersect at x=0. Contrary to your ludicrous claim: THIS DOES NOT MEAN THAT THE VALUE OF b IS ONLY CORRECT WHEN x=0; it always has that value in the equation. So this mathematically proves that you claim that we cannot use a "special case" more generally is wrong. We can, of course, calculate the values of m and b using any arbitrary x and pairs (just as we can derive the the Lorentz transform using any combination of frames in relative motion). It just becomes slightly more complicated.
  7. 4 points
    Wow. I was wrong on so many levels here. Haha thanks for the insight
  8. 4 points
  9. 4 points
    Do you understand that one side lied, broke the law, got prosecuted + fined + reported to the police for criminal action, and the other side didn't? Are you somehow pretending that the situation was symmetrical? Well, it's hard to say. But racism is wrong, and played in favour of "Leave" Xenophobia is wrong, and played in favour of "Leave" External interference is wrong, and played in favour of "Leave" And the margin by which thecheats won is small. Imagine this was a football game and, after the match, it emerged that the winning side had played a "ringer". The acceptable outcomes would be that (1) The cheats would lose by default or (2) there would be a rematch. Why does anyone think it is reasonable to hold the future of the UK to lower standards of propriety than they would for a game of football ?
  10. 4 points
    By what you would visually see, then yes, you would see events occurring faster at Andromeda. Though you couldn't actually travel at the speed of light, just close to it. The equation for this relationship is fo = fs sqrt((1+v/c)/(1-v/c)) Where fo is the observed frequency, fs is the source frequency, and c is the speed of light. Note that if you make v=c then you end up with fo = fs sqrt(2)/0) And the division by 0 is undefined. ( but since travel at the speed of light is not allowed, this never arises.) However, just because you are seeing events unfold more quickly at Andromeda, does not mean that you would conclude that they were unfolding faster. Once you account for the effect caused by the decreasing distance between you and Andromeda, you would conclude that events were actually unfolding slower at Andromeda. For example, if you were traveling at 0.99c, you would see events at Andromeda as happening 14 times faster, but would conclude that they were happening 7 times slower. The 7 times slower would be due to time dilation, while the 14 times faster you see is due to Relativistic Doppler effect, which is a combination of time dilation and the effect caused by the decreasing distance. Even this is only a part of the whole picture. In order to understand what happens over the whole trip from Earth to Andromeda according to both Earth and ship would involve delving more deeply into Special Relativity.
  11. 3 points
    There are many stunning photographs at APOD [Astronomy Picture Of the Day] some far more stunning then others...just type in APOD...a new one everyday. Here's another..... SEIS: Listening for Marsquakes Image Credit: NASA, JPL-Caltech, Mars Insight Explanation: If you put your ear to Mars, what would you hear? To find out, and to explore the unknown interior of Mars, NASA's Insight Lander deployed SEIS late last year, a sensitive seismometer that can detect marsquakes. In early April, after hearing the wind and motions initiated by the lander itself, SEIS recorded an unprecedented event that matches what was expected for a marsquake. This event can be heard on this YouTube video. Although Mars is not thought to have tectonic plateslike the Earth, numerous faults are visible on the Martian surface which likely occurred as the hot interior of Mars cooled -- and continues to cool. Were strong enough marsquakes to occur, SEIS could hear their rumbles reflected from large structures internal to Mars, like a liquid core, if one exists. Pictured last week, SEIS sits quietly on the Martian surface, taking in some Sunwhile light clouds are visible over the horizon.
  12. 3 points
    Your childish antics are fooling no one and they are taking away from the debate. We all know the meaning of what you've said and you trying to obfuscate their meaning with your hand-wavy tactics are just making you look foolish. It would have been much simpler to simply say "yes, that may not have been quite accurate" and move on.
  13. 3 points
    Again, this is the problem with just looking words up in dictionaries. "Religious faith" and "religious delusion" are not synonyms. The first is the subject of this thread. The second might be what some people think of religion (and hence is off topic). Stop trying to derail the thread with your misrepresentation of the meanings of the words being used in this context.
  14. 3 points
    I must say I was disappointed with both the premature closure of this thread on power generation and the immediately adverse and even hostile reception a new member received. https://www.scienceforums.net/topic/118572-i-offer-the-innovation-green-technology-of-generation-of-the-electric-power-by-means-of-a-new-renewable-energy-resource/?tab=comments#comment-1099130 I say premature closure because I have just looked at the thread for the first time and it is already closed. So I have no opportunity to offer some encouragement and perhaps a way forward to the new member. Any schoolboy with would be able to build a conventional model generator, perhaps powered by a hamster on a treadmill, for just his pocket money. So should we not be asking; " Can you build a small scale demonstration?" Pretty well every project starts with such a pilot.
  15. 3 points
    An international research team, including a member of the Complexity Science Hub Vienna, investigated the role of "big gods" in the rise of complex large-scale societies. Big gods are defined as moralizing deities who punish ethical transgressions. Contrary to prevailing theories, the team found that beliefs in big gods are a consequence, not a cause, of the evolution of complex societies. The results are published in the current issue of the journal Nature. https://phys.org/news/2019-03-complex-societies-gave-birth-big.html
  16. 3 points
    Not at all. Inflationary theory is part of the BB scenario and was added to explain a couple of anomalies, namely the Flatness and Horizon problem. The main proposal of the BB, is that the universe/spacetime evolved from a hot dense state. We have ample evidence that this is so. https://en.wikipedia.org/wiki/Big_Bang Timeline of the metric expansion of space, where space (including hypothetical non-observable portions of the universe) is represented at each time by the circular sections. On the left, the dramatic expansion occurs in the inflationary epoch; and at the center, the expansion accelerates (artist's concept; not to scale).
  17. 3 points
    Yes, he is, but QuantumT is using "you" to refer to all mods, and specifically referring to me in terms of shutting threads down. If the speculative thread dealt with physics, I'm the mod most likely to have interacted with you (over the years) Is it too fast? Well, that depends. We have received comments where people have complained about threads being left open too long, and begging us to close them. The people whose thread was shuttered rarely agree that they should have been locked. Bottom line is that there is no moderation strategy that will please everyone. The mods use their best judgement, built upon doing this for a number of years, and seeing a lot of people come and go. You in particular? In your first thread I tried to nudge you into compliance with our rules. That you needed to be more forthcoming with information. The thread was shut down after you announced "I will not participate in this open forum anymore" But you weren't true to your word. You came back, and to be honest, you lose a certain amount of goodwill from the mods when you pull a stunt like that. Once again, you were not forthcoming with information needed to support your position. That thread was closed, with a note that said if you did present supporting information, you could re-introduce the topic. I don't see where you took us up on the offer. The last one shut down was where you admitted you didn't understand the physics, and yet had a conjecture. I explained that this was not living up to our expectations, and at this point you had twice been given feedback on the matter of being able to support your ideas. Thus I had zero confidence that simply giving some feedback and letting the thread continue would improve matters. That was your third strike. The fact that you are placing the blame elsewhere tells me you haven't absorbed this feedback at all. So the question that I have is how many chances do you expect, when you show no improvement in your behavior?
  18. 3 points
    And I thought it was something to do with corona
  19. 3 points
    I'm not going to quote snipe back and forth. I'll just post my thoughts in hopes of finding places we agree again. When we discuss topics like healthcare, everyone always trots out the "how are we going to pay for it" canard. Some people object to this seemingly reflexive response because it never seems like we have that same response when discussing military spending, going to war, cutting taxes, etc. There is always room for spending. There are tools we can use to account for it. The government budget is not like a household budget. Taxes can be increased. Money can be printed and borrowed. There's always a need to be vigilant and not do these things in excess, and there's always room for discussion around what the threshold should be for what IS excessive and what is NOT excessive, but to boldly proclaim it all to be impossible then drop the mic and walk away is what is truly absurd here. I'm not arguing for pure spending or permanent spending. I'm saying we can shift money from place A to place B, and that we also need to account for future returns. After all, that's what the GOP does when arguing for tax cuts on the rich... I have seen many people (most often conservatives) frame government spending as a pure cost, and I personally feel that's a mistake... a completely unrealistic perspective on how economies operate. Now... This is my opinion, and it's perfectly okay to hold a different one, but I frame these issues instead as investments. What is the expected return? Will this increase jobs? Will this reduce poverty? Will this enhance wellbeing? How will these affects impact revenues and growth? What are the costs of inaction (this last one is especially relevant when rebuilding after hurricanes for not proactively addressing climate change). It's just that this constant and immediate shitting on ideas is so one-sided and so hypocritical from one topic to the next. These calls for detailed payment plans when the topic relates to healthcare or green jobs programs... these defeatist attacks that suggest forcefully that "WE JUST CAN'T DO IT!!1!!2!one!!"... yet at the same time and from the exact same people deafening silence when it comes to giving massive handouts to corporations or adding a few hundred billion for the military or lobbing a few multi-million dollar missiles into the desert overseas somewhere... Nope, not a peep! Nothing. Nada. Zilch... Crickets in an amphitheater. And don't even get me started about when actual payment plans are shared and just get swept aside in strawmen and scaremongering... The core issue here is about what we choose to value. It's the politics that are hard, not the economics, yet it's always the economics used to short-circuit the conversation and prevent us from even talking about these ideas or creatively finding ways to achieve them. Seriously... You're going on about how we cannot afford healthcare, yet today already we pay something like 3x what most other civilized nations do, and we have generally worse outcomes, lower quality care, and we don't even manage to cover everyone. We don't need to invent this from scratch, we just need to look at what's working elsewhere, claim it for our own, and stand up to fight for it in good faith. This is not a problem of budgeting, it's a problem of priorities. Now... AOC is just the newest foil for the right. She's the new bogeyman being used to get people all lathered up and wetting their pants and distracted from reasonable dialogue, but no matter how many times you repeat the word math or call her arrogant or pretend you're taking some arbitrary high-ground... no matter how many times you call her a liar for using poetic license on a single news article and no matter how much you get yourself all worked up into a tizzy and tell us all you're taking your ball and going home... there is just nothing about what she's suggesting that is either impossible or unworkable.
  20. 3 points
    Unfortunately, I'm not sure how much the public has learned. For example, I saw the results of a survey where 26% of the people asked thought that "no deal" means maintaining the status quo. If a significant proportion are going to vote for the most damaging option because they think it will leave thing as they are, then I'm not sure another vote will be any more meaningful. But that isn't the argument being made. Let's say you agree with some friends that you are going to go out for a meal. So you follow one friend who takes you to a restaurant which is filthy but really expensive. You remember seeing news stories about people getting food poisoning there regularly. Do you: a) Ask you friends if that is really where you want to eat, or would they prefer that nice place next door? Or b) Say, "well we decided to go out to eat, so we have to eat this disgusting place, whether we want to or not." After all, it would be betraying the original decision if we voted on where to eat now we have seen the options. We should never have had the first one. They are a really bad idea. And if you are going to have one for a major constitutional change, then there should be a requirement for a 65% (or whatever) majority to change things. That doesn't make much sense. In a general election would you vote for the party that won last time, even if you voted against them "to honour the first result"? You should vote for what you think is right. That ship has sailed. We have lost any credibility or honour we had. People's trust in politicians (never high) has been destroyed. I think having the referendum was a monumentally stupid idea. I don't think a second one would make things any better. But with neither the government nor parliament able to make any sort of decision, it may be the only option.
  21. 3 points
    Interpreting the hidden meaning behind a person's statements is a fool's errand. His comments could have been exactly the same whether he is innocent or guilty. No matter what he says, some will believe him, some will not. Some will think it is thoughtful, some will think he is being aggressive. Some will find him credible, some will not. Discussing whether or not we believe him or what his intentions are may be an enjoyable pastime, but we shouldn't make the mistake of believing that after a long discussion we will be any closer to knowing the truth.
  22. 3 points
    I think I’m in love. Larva of a bluebottle fly (Calliphora vomitoria), under electron microscope:
  23. 3 points
    One tip to go with all iNow's questions: Choose something which can be built in less than six months.
  24. 3 points
    I feel the real Scotsman fallacy coming... Who defines who is Christian? You? Or do Christians define themselves as Christian? Sorry, But I hate these kind of sweeping statements where you state what others should believe according the labels you use. Fascinating. The article is amongst others about Christians who accept evolution. Another one. If you had written 'most' I would have given you the benefit of the doubt, but you wrote 'all'. I know several people who also take Jesus' miracles symbolically. Yes, probably. Surely evolution made us prone to religious ideas. But religious ideas of individuals are mainly socially learned. So they may arise in the brain, but not necessarily caused by it.
  25. 3 points
    I followed the discussion a little, but did not participate because of 2 reasons: - one very practical: I am not very versed in the philosophy of language, and going into 'deep thought mode' when my daily business already needs that capacity also, it becomes a little bit too much. I simple do not have the time - the discussion about these topics have shown (inductive reasoning?) that they become emotional very soon. Which maybe funny for people who both, in different ways, believe to be rational. I have not very much hope to alleviate the tension a bit, but at least I can give it a try. Reg clearly stated a few times that he does not question the results of science. What is discussed here, as far as I can see, is the self-understanding of science, not science itself. And that is a philosophical discussion, not a scientific one. But of course, one has to know what the daily praxis of science is. If one wants to reflect on 'how science works', or the even more philosophical question 'why science works' one needs to know when scientists accept new theories, why other theories are rejected, why and how scientists err, etc etc. Until now, I did not see that Reg is principally wrong in his philosophical musings. What I see is a lot of misunderstandings. I am still not quite clear what Zosimus' position is: when he says that 'science is wrong' and scientific theories do not play an important role in the development of technology, I think he is clearly wrong. Just to conclude from that it happens that (technical useful) discoveries are made without any theory does not question the relationship between praxis and theory completely (e.g superconductivity was completely unexpected, and the theory came much later). I just want to add that the problems of the relationship between language and reality are notoriously difficult, and a simple 'we know that science works' is not very clarifying in trying to understand how it is possible that science works.
  26. 3 points
    So, some of the things you mentioned that folks describe you (e.g. unmentorable, or getting accused of falsifying data) are quite significant red flags. But without knowing context, it is difficult to tell whether you got in some unfavourable situations or whether you contributed to them. The other part are unrealistic goals. As a PhD candidate it is not typical in biomedical research to expect publications within the first year, unless you finish up someone else's work. And even then the PI typically rewrites the whole thing, anyway. From the perspective of a mentor your description of the events mostly show that things happened and that you are upset with it. But it does not tell anything about your suitability for a science career (or any other career for that matter). From my perspective you have to deal with two things. The first is the emotional aspects, which Koti covered. The second is figuring out the tangibles that got you these evaluations. How was your relationship to your supervisor, what were the issues, how did you address them, were you dismissive... and so on.
  27. 2 points
    Here is the arxiv article https://arxiv.org/abs/1906.03369 Hrrm how to simplify this. Ok let's give this a shot. In classical physics you have the E and B fields for electromagnetism however in QM those fields are replaced by the probability potentials [math]\phi[/math] and [math]\mathcal{A}[/math] now in regions where the E and B fields are zero you can still have potential via the wavefunction that the [math]\phi[/math] and [math]\mathcal{A}[/math] are non zero This tells us that the QM and QFT subsequently treatments is more fundamental than the classical treatment in that it is more complete in the information of the EM field. In essence the paper helps confirm that the probability wave functions do have a physical and measurable effect through their potentials. For example it's also a key aspect to how a particle wave packet can go through two slits at once.
  28. 2 points
    They must spend a fortune on custom-made hand puppets for this type of briefing.
  29. 2 points
    This is the key. Right now, insurance money (which the taxpayer has paid) and tax subsidies (which the taxpayer has paid) are being based on maximum profit like any growth business model. The problem is that healthcare needs to be aimed at caring for people's health in order to be effective. In the US, the focus on profit allows businesses to leech away funds that the taxpayer needs. One example among many is durable medical devices. Businesses are allowed to create monopolistic deals with doctors offices for oxygen, blood, and sleep devices. There's no competition for them with your provider, so you have no choice when they fail to provide their services, or overbill, or send the wrong filters/tubes/parts. They learned this from the cable TV giants, who similarly have no competition within their protected areas. Customer service becomes a big joke (google Apria Healthcare or Comcast customer service and look at the comments!). We definitely need a more European attitude about spending on social requirements (which I feel healthcare is). In the US, we let capitalism build the paths our socialism takes, and wonder why all our money gets leeched away.
  30. 2 points
    It doesn't have to. But as Strange already notices a lot of people like to understand their world and themselves. I belong to these kind of people. Fully agree. But I do not see why that contradicts the will to understand consciousness. For me it is just the opposite. Depends on the subject: but if people as a group want to decide on actions they should agree on the facts and the norms, and be able to distinguish them. And science is the most objective search for facts. Just think about climate change deniers. I definitely want to hear what science has to say here, and I am disgusted by the science denial of the so called 'climate skeptics'. That is what happens if you follow gut-feelings. It is very comforting 'to know' there is a fire ladder when the building burns. Except that objectively there does not exist one, it was just your gut-feeling. When the fire breaks out, it would have been good for you to know you shouldn't have gone that way to escape the fire. No. However, I would prefer that people act from the best knowledge we have available. See climate denial again. Why would you think I do not grasp the immediate reality of death? I dismissed nothing, except the categorising as 'metaphysical'. I agree that such experiences can change your gut-feelings. Ideally you develop your gut-feelings in such a way that they correspond with what we know to be objectively the case. But that requires a lot of training, but staying in your comfort zone, you will never get there. Your life will be a lie. Me neither, but in a different way you do. Physical reality is able to produce such beautiful things like galaxies, paintings, music and humans. The problem is that some of these (except maybe galaxies), cannot be understood from their basic building blocks. Even the essence of certain things is independent from the exact way it is implemented in the physical world. A house is a house, but it can built it with concrete or wood. Being human, however I agree that our essence is not that we are built up of matter: it lies in the ways processes take place in this matter. And to know these, both from the inside (studying my own mind) as from the outside (science) might be the best way to live a balanced life: accept what just is so, change what can be changed, and the wisdom to distinguish between the two (paraphrasing I think an Irish prayer). Yes, you are afraid to leave your comfort zone. And the closed mind is yours, and is exactly what I named it here: your comfort zone. But be sure, nobody got enlightened by staying in their comfort zone. It is, to use another dangerous word, not very spiritual not to accept ideas because you do not like them. Physical reality is the ocean. And the truth at the bottom of the mind might be emptiness. As practicing Zen Buddhist, I think that would be the last truth (not experienced myself, therefore 'I think' and not 'I know'). Which you of course you do not like, and therefore you refuse to accept reality.
  31. 2 points
    Certainly not parallel universes. But if it provides evidence of mirror matter then it is possible (but not certain) that there could be large scale structures equivalent to stars and galaxies, made up of mirror matter. This would exist in our universe but not be directly detectable. That could be described as a "parallel universe" but it requires a bit of journalistic license. There is a good overview of mirror matter here: https://en.wikipedia.org/wiki/Mirror_matter
  32. 2 points
    Implicit in this response is the suggestion that you've read through every single other thread that has arisen here through the years on the topic of IQ. Given that you haven't, not only are you a troll, but you're a liar... and I know who you are... have you seen you enough times under other usernames.
  33. 2 points
    For someone who has previously accused others of insults and ironic answers, your reply seems pretty arrogant and reflective of your intentions of not listening beyond your own closed mind as evidenced in your quoted statement. Being someone who is totally bereft of the maths and actual inner workings of SR and GR, may I thank Strange, Swansont and particularly Ghideon with your excellent sketches and explanations that even I am beginning to understand.
  34. 2 points
    The only centers and boundaries we can logically speak of, is the center of our "observable universe"...which of course anyone can legitimately claim, from wherever he is. While knowledge and data of BB model only goes back to t+10-43 seconds, cosmologists are able to reasonably speculate re those early times. During those early times, the four forces we know of today were united in what was called the "Superforce" As space expanded and temperatures and pressures dropped, this superforce started to break up or decouple, gravity being the first. This created what we call phase transitions and false vacuums. eg: the phase transition of ice to liquid water. These false vacuum states may also be responsible for the Inflation epoch. http://cse.ssl.berkeley.edu/bmendez/ay10/2002/notes/lec19.html During this epoch as temperatures and pressures continued to drop, excesses of energy went into creating our very first fundamental particles, quarks, electrons and such. At three minutes the first atomic nucleus was formed [protons and neutrons] The rest is pretty reliable history. The universe over large scales is homogeneous and isotropic. The same can be applied the the expansion rate...that is, it is only applied over large scales.
  35. 2 points
    I dropped out of science and math in middle school but my son likes it. I once told him “all things, everything you see, are made of atoms” and he got excited by it. We spin around in circles as atoms and crash into each other to form compounds. I bought him a periodic table and every day he asks what this and that element are, what’s this column called etc. Any info I give is from at chemistry textbooks and general science books from the library. We act things out wherever possible to make the knowledge fun and interactive. I can keep going this way, but maybe people have some suggestions on else we can do?
  36. 2 points
    The Carl Schwarzchild you mention was born in 1873. The quote I gave was from a paper read out to the Royal Society by Henry Cavendish in 1783, on behalf of Michell.
  37. 2 points
    To elaborate what I mentioned above, in order for that to happen the selective sweep must be so strong (or mutation rate so low) that any mutations would have to be strongly selected against. Especially as most mutations will be neutral this is highly unlikely in principle, which makes it very unlikely to exist in practice.
  38. 2 points
    You also need to note that there is a group of people on forums who hold a much more prestigious title than the ones who are mods - the ones who were asked to moderate and refused
  39. 2 points
    ! Moderator Note Please read the rules regarding speculations. Speculation on this site is supposed to be supported by evidence or at least an established theoretical framework. It is not a place for a freewheeling exercise in fact-free nonsense. Locked.
  40. 2 points
    Recommendation: JCMacSwell you should report a post if you think there are ad homs being leveled and everyone should stop talking about it here within thread and derailing everything. Focus on the topic... not on each other. This is not hard. It’s only hard if you force it to be. Don’t go out of your way trying to find things offensive. Don’t go out of your way trying to offend. Let it go and move forward. Treating and viewing people as individuals instead of as members of a gender seems like a good plan. It has the peripheral benefit of all of us agreeing about it.
  41. 2 points
    Further to this point, there is only one GOP congressman with a district on the border, and even he opposes the wall: https://www.nytimes.com/2019/01/17/us/politics/will-hurd-border-wall-trump.html Eight times... This month alone.
  42. 2 points
  43. 2 points
    Why not do a little research? e.g. where is your evidence that in warm periods the temperature everywhere on earth is above say -5C so that the 'top ice' everywhere melts? No. Lots of independent checks before any ice core is considered to be valid evidence of anything.
  44. 2 points
    But here’s the punch line: as a massless, spin-two field, gravity not only couples to all the other “matter” fields; it also couples to *itself*. Its field equation, both in the quantum version *and* in its classical limit, the EFE, is nonlinear. At the quantum level, this means gravitons (the quantum particles associated with the massless, spin-two field) interact with other gravitons. At the classical level, it means that, since the EFE is nonlinear, curvature can be present even when the “source” on the RHS of the EFE is zero, i.e., there can be vacuum solutions of the EFE that have curvature present. (Schwarzschild spacetime is an obvious example.) In other words, on this view, the answer to our question is “yes”: gravity *does* gravitate! It’s important to note that there is no contradiction between the two answers we have just described. “Gravity” in the two answers means two different things: gravity as a massless, spin-two field (either quantum or classical) does gravitate (the field interacts with itself), but gravity as a tensor satisfying the Bianchi identity doesn’t gravitate, because there is nothing “left over”, once the Bianchi identity is satisfied, to contribute to the source on the RHS of the EFE. I'm not sure what your actual overall position is. But, see above. Is sounds like that because of the way he explained it. The "nothing left over part" and that equations being nonlinear. So it can be neglected at lower values. I don't see why that's a big deal here. You complain that something isn't present, although it is, and also note that in most cases it's too small to account for. I don't understand what your actual objection is. Where is the prediction wrong? How would this be evidence against GR? You mentioned this, but have not actually explained why it's allegedly a problem.
  45. 2 points
    There are billions of options in between. Comments like this suggest a profound failure of imagination and experience, not some fundamental truth. Really, much of this is about which visual we choose to look at. THIS: OR THIS: I, for one, feel that as a country of nearly 350 million people and more wealth than the planet has EVER seen, we CAN find a way to include these folks within the population of “us.” I see neighbors and friends and colleagues in these photos and I don’t wet my pants when a mommy fleeing violence with her babies walks cross an arbitrary line looking to work hard and contribute, but YMMV
  46. 2 points
    4 nuns arrive at the Pearly Gates of Heaven. St. Peter is there to meet them with a bowl of Holy Water. St. Peter goes up to the first nun and says, "Have you ever touched a penis?" The first nun responds, "Yes I have. I have touched a penis with the tip of my finger." St. Peter holds out the bowl and says, "Dip your finger in this Holy Water, and be free to enter the Kingdom of Heaven." The first nun gladly follows the instruction and proceeds to enter Heaven. St. Peter goes to the second nun and again asks, "Have you ever touched a penis?" The second nun replies hesitantly, "Yes. I have touched a penis with my whole hand." St. Peter smiles and says, "Do not despair, simply dip your whole hand into the Holy Water and enter the Kingdom of Heaven." The second nun quickly does as she is told and gladly steps forth into Heaven. At this point the fourth nun cuts in front of the third nun and says, "Listen, I better go next because I'm not gurgling that shit after she sticks her ass in it."
  47. 2 points
    Abstinence only sexual education goes hand in hand with the pro life movement. It's virtually impossible to disentangle the two. The problem with this is that abstinence only sex education doesn't reduce the rate of premarital sex. What it does instead is leads to people having sex without the knowledge of how to prevent the spread of STI's. So, it not only fails at its intended purpose, it needlessly exposes people to preventable infectious diseases. In a similar vein, stricter abortion laws are not only correlated with higher abortion rates, but also an increased risk of death for women seeking illegal medical procedures. Legislating morality generally backfires. Approaching people with compassion, without judgement, and trying to minimize suffering tends to lead to a positive result for all.
  48. 2 points
    Just to add that the reason that the original star collapses is that it runs low on hydrogen for fusion, and it was fusion energy that was preventing collapse. When the star explodes, the 75% that escapes takes most if not all of the remaining hydrogen, so the 25% that is left can't keep fusion going, so the star can't just keep burning at a smaller size. Without the release of fusion energy, the remnant collapses down to a super dense ball of neutrons, called a neutron star, if it's mass is less than about three times that of the Sun. If the remnant is bigger than that, it can't maintain it's structure, and it collapses further as a black hole.
  49. 2 points
    Ironically MigL was worried about character assassination just a couple of weeks ago for a conservative up for a lifetime appointment yet is now engaging in it against Khashoggi.
  50. 2 points
    Trump says far worse things nearly everyday than Hirono has every said. Your equivalency is absurd.
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