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    Physics forums and anonymity

    Yes and it's quite annoying that the government cannot manage to secure that information.
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    Physics forums and anonymity

    That's true, but we don't live in a perfect world, so there is no perfect solution. However, given that connecting the dots can lead to people being denied health insurance, jobs, housing, etc., one has to decide what is a priority. Also, just because a name looks like a real name does not mean...
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    B Why is it assumed communication through entanglement would be FTL?

    Define a "preferred frame" that is consistent with relativity. The only definition of "preferred" that makes sense is one in which the measured values are some "true values" to which other frames can be referenced and not lead to contradictions.
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    B Why is it assumed communication through entanglement would be FTL?

    I disagree. There is no sensible definition of "preferred" that would be self-consistent.
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    B Why is it assumed communication through entanglement would be FTL?

    But that cannot be correct. The measurements are spacelike separated, so they are made simultaneously. Neither measurement can occur "before" the other and create a cause and effect relationship because they cannot be time ordered. You would have to reject relativity. Apparently, what people...
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    B Why is it assumed communication through entanglement would be FTL?

    Relativity tells you that the events (sender and receiver) are spacelike seperated and therefore cannot be time ordered. That means there are some frames in which the assumed receiver gets the message before it is sent.
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    Light testing for leaks in a thin metallic membrane

    The op did not ask about locating the holes or cracks. The op only asked about finding out whether or not there was one.
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    Physics forums and anonymity

    Another argument for annonymity is that if you use your real name ANYWHERE, you may unintentionally end up with no privacy more places than just here. It's not so much that using one's real name here is a problem if it happened in isolation, but the possibility of using that information to play...
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    Light testing for leaks in a thin metallic membrane

    Well, since a phototube can count photons at the single photon level. I'm not sure how much more accurate you could get. Those are used in spectrophotometers. They are sensitive enough that if there is enough light for you to see, it's way to bright for a photoutbe. Light through a pinhole...
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    7.2 cubic metres of Nitrogen compressed, will last 30mins-1hr of usage

    If you are going to fill lots of tires, you would be better off using a liquid nitrogen dewer. Those have gas phase valves that allow you to take warm gas out. Since nitrogen goes from liquid to vapor at an expansion ratio of a little over 600:1, you can pack a lot of gas into an LM2 dewer...
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    Light testing for leaks in a thin metallic membrane

    A photomultiplier tube is off the shelf and you can count photons with it. There are also avalanche photodiodes available off the shelf. You don't need complicated intruments to look for light leaks. All that's required is the phototube (or avalanche photodiode), a power supply and an oscilloscope.
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    Light testing for leaks in a thin metallic membrane

    You might try a photomultiplier tube.
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    A Interpretation of Bi-207 decay spectrum

    Gammas from the decay of the 207Pb excited states. Look up the level schemes.
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    High current power supply for servos? 40+ amps

    Find used sorenson power supply. They make lots of supplies that will fit your needs. Try ebay, but watch out for shipping costs.
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    Automotive Design of a Valve stem cross section in a Steam turbine emergency valve

    I don't know for certain, but the best place to look and the place you would most likely get the most information about the requirements to meet engineering standards are the ASME manuals.
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    I Can a cornering motorcycle go faster if the rider puts a knee down?

    That is not quite how that works. The reason that riders put tgheir knees down (or possibly a little short of actually touching the ground) is that they use their body position to gauge their lean angle so they don't exceed the leangle possible for the bike. The knee actually doesn't function...
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    Construction Making a gong stand - will aluminium tubing be strong enough?

    The gong only weighs 15kg. The Aluminum tubing you are using is certainly strong enough to support the gong. (Remember that airplanes are made from aluminum although the aircraft alloy, 7075T6 is stronger than what you are using, it's not THAT much stronger. (It's also brittle and unweldable so...
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    How do I gain creative experience in engineering?

    Well, even worse was that what the person made which could not be disassembled without a cutting torch was a collimator and faraday cup containing a tritium source that was supposed to be bolted to a vacuum system. Explosive bolts would have drawn some really severe frowns from the health...
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    I Confused by nonlocal models and relativity

    I think you missed my entire point about relativity being wht is confusing people, not the quantum mechanics because you seem to be missing the entire point about time ordering of spacelike events. Spacelike events CANNOT be time ordered, whether you are talking about entangled photons or any...
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    How to choose a JFET

    You might want to consider dual matched, very low noise pairs like the LSK489 series.
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    Designing an Automatic Coolant Monitoring System for CNC Machines

    As I understand your question, you cannot do this, at least if you need to maximize the utilisation of all of your machines. Different materials and different cutting tools require different coolants and different operations require coolant to be supplied in different ways. (As an example of the...
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    I Confused by nonlocal models and relativity

    Let me add a little food for thought. Unlike classical theory in which the electrons would spiral into the nucleus in very short order, quantum mechanics explains this just like it is without any additional frufru added. Similarly, we have the fact that there exist things like electrons which...
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    Anti the Anti-Vaxers

    If you read the packge inserts for even the most benign medicines that almost no one would blink an eye at taking, you can find all sorts of horrible potential side effects listed which get worse as the percentage of incidence becomes smaller. If you took those seriously, you would never take...
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    How do I gain creative experience in engineering?

    Let me add on to this from personal experience when I started graduate school to become an experimentalist. My advisors were really big on being able to build and/or fix equipment in the machine shop, since the shop people were not around on weekends and holidays when were often using the...
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    How to calculate the series ##\sum_{x = 1}^{\infty} \frac{sin(x)}{x}##

    You could try replacing ##\sin(x)## with it's representation as an infinite product.
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    I Confusion About the Born Rule

    Possibly, but I'm not sure if there is any point. Quantum mechanics is essentially an an extension of classical probability theory, so I'm not sure the Born rule is really out of place as a fundamental axiom. In any axiomatic stystem, you have a choice of which statements take the role of axioms...
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    Anti the Anti-Vaxers

    I disagree. A person who is unvaccinated and acquires measles or whatever, places those people with compromised immune systems at risk of dying should they pass along the infection. My parents are 89 and 90 and I don't think they should have to worry about catching some disease that could easily...
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    How do you solve such an ODE?

    If there is a particular method or if this is a specific type of ode that lends itself to a straight forward solution, then I don't off hand, know what it is. Sooo, what I would generally do after rearranging it and trying to change variables into something I recognize is to just find a series...
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    I Nuclear physics prospects

    Actually, you can learn a good bit about fundamental physics through nuclear reactions. In particular, you can study the CKM matrix via superallowed fermi transitions and pin down the the fermi coupling constant. Other ways to study fundamental physics in nuclear reactions is to look at specific...