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Everything posted by imatfaal
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Thanks will try that.
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And it seems that one must refresh to see it even when posted. But I like the rendering, and loads of extra gadgets on right click. The hover to zoom is very useful for those of us with imperfect vision
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\( equation in line \) \[ equation in block \] checking \(F=ma_{centripetal}=mr \omega^2 \) \[ \omega^2=\frac{a_{centripetal}}{r} \] Straight [latex] tags no longer work - although [math] tags apparently do - but it is much quicker to type as above
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What is the obsession going to the moon or mars?
imatfaal replied to nec209's topic in Other Sciences
Using back of the envelope calcs I have even carbon nano-tubes producing a max radius of 33km being both self supporting and spinning fast enough that centripetal force is roughly earth like. -
And I guess that means all religion resolves down to a question/debate about whether we have processed the 20 PRINT "Hello World" program line yet?
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This is very like Nicomachean Ethics - Aristotle. The ethos is to lead a virtuous life - that is to say in this context - a life which allows one to flourish and become all that one's potential might allow
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"creationists are, potentially, a danger. But by themselves they have no real power. It is when politicians collude with them OR HOLD THOSE VIEWS THEMSELVES that there is a real risk" Added an important (to me at least) to your latest. And surely the biggest religious belief causing problems for the advancement of science is to be found within climate change. A large part of the well-heeled and well-organized disruption of scientific work in this area is caused, at its root, by a belief in a world created by god for humans
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Table salt is far more hygroscopic than rice isn't it? The problem with salt is that you really do not want salty water near your electronics or even bare metal in general
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First small point. Milky way is gravitationally bound to Andromeda; they are in (complex) orbit with each other and various minor satellite galaxies Expansion. Two things flying apart in normal space. No change in energy - conversion of kinetic to potential. (if you are talking about an outside influence moving two galaxies apart - then yes huge energy required) Accelerated Expansion. Now this is where it gets difficult. When the space through which particles are moving is changing then energy is not conserved. You could also think that all the conservation laws are parallels to translation laws - Noether. Energy conservation is the same a time reversibility - but the change in space is one directional so we do not see this as an time reversible / energy conservational process
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Yes but how much water does it take to repressurize your evacuated chamber?
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Removing water can be thought of as a two stage process - water leaving item to immediately surrounding air, water laden air being removed from immediate environment / water being removed from air and sequestered away from item. To maximise water leaving item you need to raise both parts of process - yours would only change the first section. Best bets are warm environment with steady air replacement or desiccant.
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[math] y = \int f(x) dx [/math]
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inline \( y=x^2 \) check \( y=ax^2+bx+c \) display \[ x= \frac{-b\ \pm \sqrt{b^2-4ac}}{2a} \] \[ y = \int f(x) dx \]
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FFS - How many people in a football team? If I make the question simpler do you understand the idea? So still simplified How many people in the White House Science Office?" Maybe Trump has a point - argue about the phrasing of a question rather than debate the substance - give me strength.
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The United States has had more Nobel Laureates in history than any other country (more than top five other countries combined)* - so bearing in mind that incredible heritage ... Question: How many people in the White House Science Office (technically The science division of the White House's Office of Science and Technology Policy (OSTP) ) as of Friday close of business? *including Peace prize and Organizations - I couldn't be bothered to find a list of just real person Science prize winners.
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Bullet fired from a gun and a bullet dropped descend simultaneously
imatfaal replied to StringJunky's topic in Relativity
I am not convinced you and Tar are right there. The sphere is length contracted but very odd things happen when you "look" at it - light (very fast as it is) still has a finite transfer time, and when you are "looking" at something which is moving at a sizeable fraction of the speed of light one must not think of transmission as instantaneous. If I have remembered correctly a sphere being observed will appear to be a sphere rotating (the direction of rotation is as if it is rolling along a floor and we are looking through the floor). The phenomenon is called Penrose-Terrell rotation. NB this is just what the sphere looks like to an observer - it is actually flattened -
Brilliant! A plus one on both your Houses Posts. I thought the more prosaic version with word instead of name fitted better.
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I think it is the OP's own website - and yes, I agree with your characterisation
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At least for Toyota that might be difficult http://www.toyota-global.com/showroom/emblem/passion/ The old one was really impressive (flying kanji for toyoda)
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- nope but I can see the logic not that - but again can see the thinking
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An on-topic Shakespeare would have to be 23812019,914,1,141135,208120,238938,235,311212,1,1815195,225,11425,15208518,2315184,231521124,191351212,119,19235520 There is a green plus one from me for anyone who can work it out...
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I was just saying in another thread that I think we are reaching peak-online. Not that amount online will fade - but we have reached a situation where it is asked "is it worth putting this online" rather than "can we put this online". The novelty and the thrill of sharing information is wearing off - in situations in which there is a gain to be had then we can go online very easily now and thus there is no advertising premium for being online just for the sake of it. I remember signing up for stuff purely because I thought it was cool to do this or that online. Now, as with smart-phones, computers in general, portable vs "in situ" and many other things, we have matured as a society and grown used to these technologies - we no longer feel the need to do them just because we can
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There is not much that is forbidden for a virtual particle Here is the good Doctor Matt Strassler https://profmattstrassler.com/articles-and-posts/particle-physics-basics/virtual-particles-what-are-they/ They are "off-shell" and do not have to obey many of the laws that real particles do. https://en.wikipedia.org/wiki/On_shell_and_off_shell Note that Noether's theorem is the mathematical treatment of conservation laws / invariance under transformation
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No I missed that - but I can imagine. I am no old fogey - but I do think that a fashion in teaching allied to insidious cost cutting has led to a real decline in the methodology of examination. I do not hold with the "everything is getting easier" mantra that is so easy for those of us with pockets full of exams to trot out every August - I think children, young adults, and students in further/higher education work harder (and with less financial) support than I ever did. I think we are at peak-online; we are realising that whilst online access can be world-changing somethings are just better off-line. Once it is no longer a challenge to get stuff online it stops being an end in and of itself, and going to an online scenario is chosen because of a positive cost-benefit analysis rather than an online-good ideology.
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MRI tends to work on the Hydrogen in water and fats within the body. I have no idea whether it would work on stone - it is possible that the variation in stone which we can easily see in fossils is not great enough to create a variation in the nuclear spin transition and relaxation which is picked up in an NMRI scan; on the other hand maybe it does work. Just in case someone approaches you with a chance to do a scan at a cost I would contact your local university's palaeontology dept. first. If you have already done this I would be fascinated to hear response. I know NMRI can be used on other nuclear spin models - but I thought they were specially made machines Here is a link to a lecture I attended at the Royal Society - it is a few years ago and it all the info seem to have fled my head https://royalsociety.org/science-events-and-lectures/2014/magnetic-resonance/