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  2. DOJ and FBI under attack

    It is definitely all one big game to the White House. I means to defame those who speak truth to his actions. It is very sad that after 21yrs of service McCabe may possibly lose the pension he has earn because partisan politicians lack the integrity to act. Though it is increasingly becoming common I am still caught out guard by the casual way conservatives accept the abuses of power display by this President.
  3. Well, I’m still quite embarrassed about a few things I said on usenet 30 years ago so I can sympathise!
  4. I had to go look and see what all the fuss was about. You are stressed because of some comments posted eight years ago?
  5. Energy Density of Li-ion battery

    you can watch this video on youtube @ about 39 minute it explains a lot!
  6. An Admin could do this, and it's a great solution if this is the problem. +1 Protip: The Empress of Everything, like most people, responds more favorably to requests than demands.
  7. Making Li-Ion Batteries

    I learned that LiC is made by diffusion of Li in Graphite so it was not a chemical reaction just as I suspected but the rest remains a mystery to me!
  8. Can I second what Area54 said. And I apologise if I was a bit mean before. If you are worried because you use the same username on other sites, you could ask the mods to change it (I don’t know if they will)
  9. A question occurred to me that I think is quite interesting but I keep being told to go away when I ask it. Perhaps the physics community has become jaded by internet use. Anyway... (a) Given that all space-time exists simultaneously – Like a river I'm flowing along in ( the present). The upstream is still there (the past), and the downstream is already there (the future). And, (b) Assuming that Stephen Hawking's 'Imaginary Time' theory is possible and true – A dimension of time running at a right angle to space-time, providing a time dimension for the 'Big Bang' to have taken place in. Wouldn't that mean that all of space-time occurred in the smallest possible unit of time in imaginary time, and that all of imaginary time occurred in the smallest possible amount of space-time? If so does time really have duration and flow, or are those both simply the perspectives of observers within given dimensions? And to really stretch the point...Is it possible that every possible time dimension (universe) is just a 'potential' time dimension, within the smallest possible unit of time, within a singularity? Meaning that the 'Big Bang' hasn't taken place, but has the 'potential' to take place, but that from my perspective, the 'Big Bang' has taken place because I'm a 'potential' observer within a 'potential' time dimension. Thus, everything that has ever existed, ever could exist, or does exist, always has existed and always will exist. Keep in mind, I am not saying that this is the case, I'd be happy to be told that the whole thing is impossible because... I just found it an interesting thought.
  10. Today
  11. I've come across the trend that almost all crops lost genetic diversity during domestication as a result of selection. But some species seem to have lost more than others. For example maize retains around 83% of its diversity but rice retains only around 10-20%, yet they likely both suffered similar selection pressures. Is there any reason why there would be such variation in genetic diversity loss? I know perennials have retained more diversity than annuals because they've experienced fewer bottlenecks, having only recently been domesticated. But why would maize and rice, both domesticated at similar times and with similar selection pressures, have such variation?
  12. Vak, no one likes to think they have made a fool of themselves in public. The good news is that you have not. No one knows who you really are. The name, Vak, contains no significant clues. For all I know you are my next door neighbour, or live in a city on the other side of the planet. You are completely anonymous. So there is no need to stress. Apprently you posted some foolish things. If those are deleted the fact that you thought them and posted them still remains. Deleting the posts does not change that. Use this experience as a positive opportunity.
  13. Ah, so you are not Eastern Orthodox?
  14. We don't delete ever, as part of our transparency policy and also because members take their valuable time to participate in science discussions. We're being respectful of everyone involved, in the best way we can. The fact that it looks like your head is on a pike as a warning to others is purely coincidence (and entirely your fault, yes?). But I'm assuming that's your grievance, that the posts make you look bad? If I'm wrong, please correct me.
  15. Not wishing to start an argument ( ) but I think you mean pin ...
  16. I feel such a relief after reading your post. You cogenty phrased what I was trying to say all allong in this thread, I will definitely need to work on the way I am conveying my thoughts by written text. A giant plus 1 for this one Eise. Oh and you got me there for a split second. I got shivers all over me when I read „Yes, you must distinguish between truth1 and truth2” as my phone displayed the sentance in such a way that it took me time to see „just kidding”
  17. Should we really have moved onto this topic beofre agreeing on how many angels can fit on the head of a needle?
  18. Making Li-Ion Batteries

    I am making a research about Li-Ion Batteries and I have read that Anode: Lithium intercalated graphite (LiC6) Cathode: Lithium intercalated LiCoO2 (Li„Co02) Electrolyte (Liquid): Alkyl Carbonate -I- LiPF6 [Solution of LiPF6 in a mixture of Ethylene Ofjf. Carbonate and Di methyle Carbonate (EC-DMC)] My Question is the Anode , Cathode and Electrolyte (Liquid) materials; how are they prepared by chemical reaction or by industrial technologies athor than chemical reactions? because I ma starting to doubt that cobalt and Li chemically react!
  19. Making an acid

    search on and if you do not want to use citruss acetic acid or viniger is always a good reliable option
  20. Confused about batteries

    I am not quite sure about what you mean by half cell operation I mean for discharging you always need two terminals! and you need to connect the minus terminal to ground and you need a common ground for connection or your voltmeter cannot read a floating terminal. a voltmeter has two terminals we are not dealing with coulombs!?
  21. What does melatonin do ?

    The hormone melatonin helps regulate sleep and wake cycles. It's often used by people with insomnia or that just want to sleep 'better'. What does melatonin do on a biochemical level with skeletal muscles so they feel 'sleepy'?
  22. Yes, you must distinguish between truth1 and truth2... Just kidding. To be honest, I do not like the substantive 'truth', even less when written as 'Truth'. I think the first thing is to look on which 'objects' the adjective 'true' applies: these are propositions, or complete systems of propositions, where I think about e.g. scientific theories. What it means is that they fit to what they describe. If they do not, they are false. (Or they are meaningless ('colourless green ideas sleep furiously'), or they do not describe a situation unambiguously ('One cannot see light' )) So simply said, one can define 'truth' as the correspondence between a description and reality. So it characterises a relationship between propositions and facts. Which e.g. means the 'Truth' is not out there. We find out if a proposition is true, if we find out that the description corresponds to reality. It is an attribute of propositions ('in there') and reality ('out there'.) I think this meaning of 'true' is simple. But that does not mean that it is easy to find out which propositions (or theories) are true. The two topics should not be confused: what 'true' means on side, and how we find out on the other. I think that some of the examples given are wrong: e.g that about simultaneity in relativity. Are two events simultaneous or not? Well, we know exactly how this depends on from which inertial frame you are observing these events. So we have to amend it to 'for observer A the events are simultaneous, for observer B they are not'. If we know how the perspective has influence on what people observe, then we know that there is nothing to quarrel about. It is as if two people are facing each other, and quarrel about the question if the chair stands at the right or at the left. If you take the perspective in account, the whole problem has vanished. Same with what is true today is false tomorrow. If it was an 'eternal truth' (something like F = mv, like Aristotle thought), and today we know it is false, then it was false all the time. We erroneously took it for true. But truth hasn't changed, because reality did not change. Same with the opposite: reality changes. It is drizzling. It is really true! I see it when I look out of the window! But of course this event is local: where I live, and am now, it is drizzling. It makes no sense to quarrel about the truth of 'it is drizzling', if I do not take the context in account. When I am going somewhere else tomorrow, then it is still true that 'in Switzerland at 17.03.2018 16:30 local time, it is drizzling'. Even if it is beautiful weather at the place where I am tomorrow. Personally, I would prefer to separate some concept pairs: For factual knowledge, 'true' or 'false' apply, because there can be a kind of correspondence between factual propositions and reality For morality, I would use 'right' or 'wrong'. There is no way that science can find out what is morally right or wrong. It can help if facts play a role in a moral decision ('if you do this some people might be killed, if you do that, the risk is negligible'). But this already presupposes that both agree on the norm that killing people is wrong. For aesthetics it becomes more difficult: beauty, interesting, fascinating or ugly, boring, ...The difference with morality is that it has a very strong personal factor. The compulsion to come to an agreement is less than in morality, but do not underestimate the intersubjective character of these aesthetical norms. If these is a discussion on how to renovate the old city centre, it can become very important that people agree. Well, then they are wrong. Truth is not subjective. Beauty has a strong subjective side, morality less, but truth is definitely not subjective.
  23. Thanks, Strange. I certainly found it very helpful.
  24. Quasi Sine Generator

    On the right side of the last message's diagram, I suggested separate supplies for the output flip-flops. While it can be useful to filter individual supply lanes for the flip-flops (in separate packages with LC cells), the phased outputs attenuate the target harmonics only if the supply potentials match very accurately, and this is best obtained from a common regulator.
  25. YES! Although it is doubtful a singularity represents physical reality. No one knows. Quantum fluctuation? Big bounce? Colliding multiverse? Other? I think that if the universe is infinite then the initial hot dense state (not singularity) must have been infinite too. I hope the OP found it (and the other answers) useful too
  26. Wow, that really made me sit up and take notice: i've never looked at it that way before. So would it be right to say, then, that the suggested singularity was the whole universe and that it "just " expanded, rather than it came into existence from nothing? I'd have to ask two questions now: why did it expand at the moment it did at the velocity it did ( as gwb in the OP has mentioned ), and is it at all possible that that singularity could have been inconceivably large even before it expanded- if that's not a contradiction in terms? +1. I wasn't able to upvote your post.
  27. about catalysator heat/electricity

    What happens when you apply electricity on one amino acid. And what happens when you apply the same electricity on a tripeptide?
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