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Everything posted by Strange
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"Relativistic mass" is just a way of describing energy. A lot of people think it shouldn't be used because it confuses people (like you).
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No. Mass means rest (or invariant) mass. Photons are never at rest and their rest mass is zero. You can calculate an equivalent "relativistic mass" if you wish. But relativistic mass is just a measure of energy, so that seems a pretty pointless exercise.
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How non-ionizing radiation causes corona discharge?
Strange replied to BorisBoris's topic in Speculations
I think that is because of the (alternating) voltage induced in the metal by the microwaves. -
This is an example of the fallacy of begging the question. And it is wrong. Why not learn some physics, instead of making stuff up? Wrong again. The momentum of a photon has nothing to do with mass. It is given by [math]p = \frac{h}{\lambda}[/math]
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Split from A real monopole magnet has been created?
Strange replied to lestouimxder's topic in Trash Can
! Moderator Note You agreed to the rules when you joined. These require that you do more than just post a video in order to enable discussion. The rules also require civility. They also do not allow sock puppets. -
Succinctly put. And, as Phi for All said, you need the 4th coordinate (“when”) if you want to successfully meet up with someone there. You can’t get away with omitting any of these, and you can’t replace one with some combination of the others, so they meet the “independent” requirement in Mordred’s definition.
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Solve the climate crisis: A thought experiment
Strange replied to wallflash's topic in Climate Science
Exactly. But there are higher level protocols (e.g. quality of service) that will prioritise some users' traffic over others. No legislation required. It works by a combination of consent and market forces. The same would apply to using electric vehicles as temporary power buffers. -
From testing Bell's Inequality. If the values were real (as in classical physics) we would get a different result from that predicted by quantum theiry. When we do the experiment, we get the value predicted by quantum theory. This is correct. But there are two different things here. There is the "observer effect" which is where attempting to measure something will have an effect on it and change the thing you are measuring. For example, putting a voltmeter across a circuit can draw some current and change the voltage. You can correct for the effect. And you can design the voltmeter to minimise it. Then there is uncertainty. There is a limit to how accurately you can measure some values even if you had perfect equipment, that had no effect on the system you were measuring. Again, one can say that the values are not even "defined" (or don't "exist") any more accurately than that. I'm not sure. I suppose, for example, the Many Worlds interpretation says that the properties exist, but there are infinite different worlds each with different values (or something - I'm not that familiar with it). Yes, realism is out of the window (or, at least "local realism"; I think you can have realism if you also allow faster than light communication; but we know that isn't possible). I don't think it solves the locality problem; they are just two (related) non-intuitive aspects of quantum theory. Whether that means that "observation creates the world around us" is more of a philosophical question. Absolutely. People here love to discuss and answer questions about things like this! One of the best descriptions I have found is from "Dr Chinese" (no idea why he uses that name). This is an overview: https://www.drchinese.com/Bells_Theorem.htm And a fairly simple worked example: https://drchinese.com/David/Bell_Theorem_Easy_Math.htm (you may have to go through it several times to get the hang of it)
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Yes, 3D space is a volume. We live in 3D space Things like points and lines are mathematical concepts. They can be useful in physics (and other areas). For example, the route between London and New York is 1D line. That is not a "thing"; but it is mathematically useful. Similarly, electrons (which may or may not be "things" depending how you define "thing") are modelled as 0D points. That is useful because it corresponds to the way they behave. Many areas of science use multi-dimensional abstract spaces. (Even "soft" sciences like social science.) Because they are useful ways of describing the world. Science, generally, isn't concerned with "reality" but about what we can measure and describe. If you want to discuss "reality" then you probably want philosophy (or maybe religion) rather than science. He did actually say that we can describe the universe as a 4D construct that combines space and time (called, not suprisingly, spacetime). All four dimensions have equal status of being "real" whatever that means. And all four are affected by the presence of mass (resulting in effects like gravity or time dilation).
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The difference is that the shoe in the box was always a left foot. Opening the box doesn't define whether it is left or right; it is inherent to the nature of the shoe. In that sense the "handedness" (footedness? chirality) of the shoe is technically "real". Opening the box just reveals what it is. Whereas the spin (for example) of a photon is not only unknown before it is is measured, but it doesn't even have a defined value until it is measured. In that sense it is not "real". So by measuring the spin, you don't just find out what the value is, you cause it to have a value. And, instantly, cause the entangled partner to have the opposite value. Another important difference is that the shoe can only be left or right. Whereas you can measure the spin at any angle and get a + or - value for the spin at that angle. And if you measure the spin of the entangled partner at the same angle, you will find it has the opposite value. How do we know that the values of the spin are not "real" (defined, like shoes, when the entangled pair were created)? Now, this is where it gets subtle and tricky (and therefore where I might well get the details wrong!). If you were to measure the spin of the entangled partner at 90º to the angle you measure the first photon, you would find there was no correlation. If you measure the spin at some angle between 0º and 90º, you will find there is statistical correlation. The probability of this correlation can be calculated assuming the particles had "real" (defined) values for the spin or they can be calculated using the rules of quantum theory. These two calculations give different results (known as Bell's Inequality). So by measuring this, we can test whether quantum theory gives the right answer or not. (Spoiler alert: it does!) Hopefully someone who knows what they are talking about will correct any errors in that! But I hope it helps a bit.
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Solve the climate crisis: A thought experiment
Strange replied to wallflash's topic in Climate Science
Well, the fact you are raising irrelevant objections and don't know how the proposed system will work might be a clue. I didn't mention the Internet. But that is another good example of an international standard that was developed without legislation. (And, interestingly, the scheme I am talking about was nicknamed the "Internet of Power"). -
Solve the climate crisis: A thought experiment
Strange replied to wallflash's topic in Climate Science
"I merely present problems I see because I haven't looked into this at all." (I will refrain from using the "i-word" to describe someone who doesn't know what they are talking about.) Do you really think that the industrial standards that allow you to connect any computer to an Ethernet port, or use the same type of memory card in your computer, camera and phone are mandated by law? "I am going to counter the information about a real project being worked on by car makers and power companies by inventing some numbers about a completely different technology" -
! Moderator Note Moved to Philosophy
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Solve the climate crisis: A thought experiment
Strange replied to wallflash's topic in Climate Science
And this is exactly the sort of problem I highlighted in my first post: people may come up with clever-sounding ideas that don't work because they don't understand all the details. Then other people (you, in this case) may dismiss perfectly sound ideas with straw man arguments because they haven't looked into all the details and assume it can't possibly work. Or, more realistically, the power company offers a deal where you get a slightly lower rate if you will allow them to borrow, say, 10% of your battery's charge - with guarantees about when/how this can happen to ensure that you are not inconvenienced and can drive your car in an emergency. But feel free to carry on with your assumption that no car manufacturers and infrastructure companies have thought about how this could work practically. wallflash: "I would love to hear everyone's ideas on how we can tackle climate change" wallflash: "No, that won't work" wallflash: "No, I don't agree" wallflash: "No. wallflash: "No" If we have this much difficulty coming up with purely hypothetical ideas between friends, imagine how much harder it must be for people who actually have to solve the technical, economic and political problems to get anything done. It is amazing that any progress is being made at all. -
Solve the climate crisis: A thought experiment
Strange replied to wallflash's topic in Climate Science
Although, all those vehicles plugged in to charge can also be a resource used to help load balance the grid. For example, people all drive home at about the same time, plug their cars in and go indoors to make a cup of tea or cook dinner. The grid can "borrow" power from the cars (they wont all be completely discharged) to meet that short term demand before going back to charging the cars. A smart grid will also know not to start charging all the cars at the same time (massive surge in demand) but to enable them on a schedule - perhaps based on requests / priority information from the vehicles. Maybe if you have a doctor on call next door, she gets first dibs on power (perhaps even borrowing from your batteries, if they are already well charged) and then you get charged next. When the doctor is not working, but you are, then you get priority. (And, yes, systems are already being designed to do that sort of thing.) -
COVID-19 outbreak (caused by SARS-CoV-2)
Strange replied to ScienceNostalgia101's topic in Microbiology and Immunology
Although it usually eaten raw. (It doesn't have much taste.) You can also have saké with dried fugu fin. That is quite tasty. -
I would be cautious about opinions of someone selling their own alternative skin care products.
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Solve the climate crisis: A thought experiment
Strange replied to wallflash's topic in Climate Science
Not at all. An argument can be qualitatively correct (eg. “nuclear power is very safe”) even if it is quantitatively wrong (“it has only ever killed one person”). -
A donut with a handle is diffeomorphic to a loving cup
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! Moderator Note I will also issue my standard warning to people: do not download Word documents from unknown sources. @nobody You need to present your idea here. If, for some reason, you need to link a document with extra details then please save it as a PDF first.
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COVID-19 outbreak (caused by SARS-CoV-2)
Strange replied to ScienceNostalgia101's topic in Microbiology and Immunology
I think a city environment is important just because of the numbers involved. If someone at a rural market comes into occasional contact with an infected bat (or snake, as most of the reports I have read suggest) the chance of a virus is low. And then the number of people they might pass it on to is also quite low. And so on. In a busy city market, thousands of people might come into contact with multiple infected animals, every day. So the chances of the virus jumping the species barrier is higher. And after that happens, they will come into close contact with hundreds, maybe thousands, more people everyday. And they may travel larger distances, contacting people who are travelling by train or plane to other large cities, etc. -
That is exactly the sort of comment that moderators here do make to people who cross (or get close to the line). Persistent offenders may get suspended or even banned. The only way you seem to be out of step with others is in seeing offensive language where others see none. I don't believe such a general attitude exists or would be tolerated by the moderation team. Stating that people who believe the world is flat are ignorant is not an insult. It is a statement of fact. Saying that if they are not ignorant they must be lying would probably not be permitted if aimed at a specific individual, even if not a member here. But as a general statement about the motives of a group, it seems defensible. As zapatos says, we know that many people lie about certain subjects for political or financial reasons. The rules, and how rigidly they are enforced, varies between forums. For example, we are fairly relaxed about general members reminding others of the rules but another forum I am a member of has a very strict rule that only moderators can do anything that looks like moderating. One has to find the forum or forums that suit you. (Which you could choose to interpret as "if you don't like it here, you can go elsewhere" )
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I think that is kind of on the right track. At first I though the long narrowing tube went inside a bottle or container. But now I think it is more likely that that is where the liquid/gas comes out and the ground glass bit goes through a tube. A bit like this: https://www.exportersindia.com/arth-enterprises/glass-stopcock-ambala-india-1948044.htm Instead of controlling the flow along the tube, it lets it drip out of the bottom of this tap. Like this, but in glass (and for more controlled/precise delivery): https://www.morebeer.com/products/plastic-carboy-6-gal-spigot.html You could try emailing a company like this: http://www.safetyemporium.com/laboratory/glassware/adapters/ to see if they have ever come across it.
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That's interesting. It made me wonder if it could be some sort of measuring device - you turn the tap to one position to fill the tube with liquid, then turn it to another to release exactly that volume. But it doesn't look big enough to hold 25ml.