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@kshegunov Quantum Mechanics

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  • tekojoT Offline
    tekojoT Offline
    tekojo
    wrote on last edited by
    #4

    As long as no-one tries to look for a "Quantum mechanics" sub-forum we can assume it both exists and doesn't exist.
    Just please don't try to look for it.

    1 Reply Last reply
    5
    • kshegunovK kshegunov

      Well, as this is the lounge (we are only missing the coffee machines) consider yourself asked. :)

      JonBJ Offline
      JonBJ Offline
      JonB
      wrote on last edited by
      #5

      @kshegunov
      LOL, I didn't mean it seriously. I am also well aware that the world is full of laymen with their own pet theories on quantum and other physics, all of which are almost certainly worthless/of no interest to anyone other than themselves.

      I also would like to say I appreciate your regular & informed input on the forums, and answers to my posts. I know I sometimes put in an OT comment, I do hope that does not detract --- I like the casual, friendliness here, I am used to stackoverflow where you get penalized or executed by hostile members for anything frivolous or not directly relevant....

      kshegunovK J.HilkJ 2 Replies Last reply
      2
      • JonBJ JonB

        @kshegunov
        LOL, I didn't mean it seriously. I am also well aware that the world is full of laymen with their own pet theories on quantum and other physics, all of which are almost certainly worthless/of no interest to anyone other than themselves.

        I also would like to say I appreciate your regular & informed input on the forums, and answers to my posts. I know I sometimes put in an OT comment, I do hope that does not detract --- I like the casual, friendliness here, I am used to stackoverflow where you get penalized or executed by hostile members for anything frivolous or not directly relevant....

        kshegunovK Offline
        kshegunovK Offline
        kshegunov
        Moderators
        wrote on last edited by kshegunov
        #6

        @JNBarchan said in @kshegunov Quantum Mechanics:

        LOL, I didn't mean it seriously. I am also well aware that the world is full of laymen with their own pet theories on quantum and other physics, all of which are almost certainly worthless/of no interest to anyone other than themselves.

        Perhaps, but the flat earth (conspiracy) theory is rather funny at least. ;)

        I also would like to say I appreciate your regular & informed input on the forums, and answers to my posts. I know I sometimes put in an OT comment

        Thanks!

        I do hope that does not detract

        You'd get a notice in chat if it does, or a moderator will fork it into another topic. I myself am rather lenient on that (see below).

        I am used to stackoverflow where you get penalized or executed by hostile members for anything frivolous or not directly relevant....

        Well, if that were the case here, @tekojo would've had put me on the chopping block more than anyone else ... :D

        Read and abide by the Qt Code of Conduct

        VRoninV 1 Reply Last reply
        1
        • JonBJ JonB

          @kshegunov
          LOL, I didn't mean it seriously. I am also well aware that the world is full of laymen with their own pet theories on quantum and other physics, all of which are almost certainly worthless/of no interest to anyone other than themselves.

          I also would like to say I appreciate your regular & informed input on the forums, and answers to my posts. I know I sometimes put in an OT comment, I do hope that does not detract --- I like the casual, friendliness here, I am used to stackoverflow where you get penalized or executed by hostile members for anything frivolous or not directly relevant....

          J.HilkJ Offline
          J.HilkJ Offline
          J.Hilk
          Moderators
          wrote on last edited by J.Hilk
          #7

          @JNBarchan said in @kshegunov Quantum Mechanics:

          I like the casual, friendliness here, I am used to stackoverflow where you get penalized or executed by hostile members for anything frivolous or not directly relevant....

          That even extends to Questions asked and anwered 100 times over. AKA:

          My Program works when it`s started from QtCreator but not when I click on the exe
          

          I'll blame that partially on the bad topic search of this forum, in most cases its easier to simply use google instead of the on side search ;-)


          Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


          Q: What's that?
          A: It's blue light.
          Q: What does it do?
          A: It turns blue.

          tekojoT 1 Reply Last reply
          1
          • J.HilkJ J.Hilk

            @JNBarchan said in @kshegunov Quantum Mechanics:

            I like the casual, friendliness here, I am used to stackoverflow where you get penalized or executed by hostile members for anything frivolous or not directly relevant....

            That even extends to Questions asked and anwered 100 times over. AKA:

            My Program works when it`s started from QtCreator but not when I click on the exe
            

            I'll blame that partially on the bad topic search of this forum, in most cases its easier to simply use google instead of the on side search ;-)

            tekojoT Offline
            tekojoT Offline
            tekojo
            wrote on last edited by
            #8

            @J.Hilk search is hard. I use google to search the forums too :)

            kshegunovK 1 Reply Last reply
            0
            • tekojoT tekojo

              @J.Hilk search is hard. I use google to search the forums too :)

              kshegunovK Offline
              kshegunovK Offline
              kshegunov
              Moderators
              wrote on last edited by
              #9

              @tekojo said in @kshegunov Quantum Mechanics:

              I use google to search the forums too

              Don't we all ... ^_^
              Btw, a nice one on the QM forum's existence. It reminded me of this particular meme:

              Read and abide by the Qt Code of Conduct

              1 Reply Last reply
              1
              • JonBJ Offline
                JonBJ Offline
                JonB
                wrote on last edited by
                #10

                I will post my own fascinating queries in this thread in due course --- I have spent so much time in the forum today that I desperately need to do some actual work....!

                1 Reply Last reply
                2
                • kshegunovK kshegunov

                  @JNBarchan said in @kshegunov Quantum Mechanics:

                  LOL, I didn't mean it seriously. I am also well aware that the world is full of laymen with their own pet theories on quantum and other physics, all of which are almost certainly worthless/of no interest to anyone other than themselves.

                  Perhaps, but the flat earth (conspiracy) theory is rather funny at least. ;)

                  I also would like to say I appreciate your regular & informed input on the forums, and answers to my posts. I know I sometimes put in an OT comment

                  Thanks!

                  I do hope that does not detract

                  You'd get a notice in chat if it does, or a moderator will fork it into another topic. I myself am rather lenient on that (see below).

                  I am used to stackoverflow where you get penalized or executed by hostile members for anything frivolous or not directly relevant....

                  Well, if that were the case here, @tekojo would've had put me on the chopping block more than anyone else ... :D

                  VRoninV Offline
                  VRoninV Offline
                  VRonin
                  wrote on last edited by
                  #11

                  @kshegunov said in @kshegunov Quantum Mechanics:

                  but the flat earth theory is rather funny at least

                  It's not funny man! they are lying to humanity!
                  Flat Earth

                  "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                  ~Napoleon Bonaparte

                  On a crusade to banish setIndexWidget() from the holy land of Qt

                  JonBJ 1 Reply Last reply
                  1
                  • VRoninV VRonin

                    @kshegunov said in @kshegunov Quantum Mechanics:

                    but the flat earth theory is rather funny at least

                    It's not funny man! they are lying to humanity!
                    Flat Earth

                    JonBJ Offline
                    JonBJ Offline
                    JonB
                    wrote on last edited by
                    #12

                    @VRonin
                    Yeah, well, I'm afraid so are the people I know who insist The Earth is about 4,000 years like in The Bible, evolution is not real, and dinosaurs either didn't exist and the bones have been "planted" or they lived about 3,500 years ago for a bit....

                    1 Reply Last reply
                    0
                    • J.HilkJ Offline
                      J.HilkJ Offline
                      J.Hilk
                      Moderators
                      wrote on last edited by
                      #13

                      From what I read, its not so much the theory that earth is flat, but that all pictures/video we have of earth in space is made by NASA, and officially graphically revised which is actually true, and therefore #FakeNews.

                      On that note #Live


                      Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                      Q: What's that?
                      A: It's blue light.
                      Q: What does it do?
                      A: It turns blue.

                      JonBJ VRoninV 2 Replies Last reply
                      0
                      • J.HilkJ J.Hilk

                        From what I read, its not so much the theory that earth is flat, but that all pictures/video we have of earth in space is made by NASA, and officially graphically revised which is actually true, and therefore #FakeNews.

                        On that note #Live

                        JonBJ Offline
                        JonBJ Offline
                        JonB
                        wrote on last edited by JonB
                        #14

                        @J.Hilk
                        For the record, The Greeks (the ancient ones, not the ones in the EU who borrow a lot of money) knew it was curved and measured its radius purely from horizon/sun/"clock" stuff, so can't see how NASA can be blamed for faking it :)

                        Whereas going to The Moon was clearly really just like Capricorn One....

                        1 Reply Last reply
                        0
                        • J.HilkJ J.Hilk

                          From what I read, its not so much the theory that earth is flat, but that all pictures/video we have of earth in space is made by NASA, and officially graphically revised which is actually true, and therefore #FakeNews.

                          On that note #Live

                          VRoninV Offline
                          VRoninV Offline
                          VRonin
                          wrote on last edited by VRonin
                          #15

                          @J.Hilk said in @kshegunov Quantum Mechanics:

                          but that all pictures/video we have of earth in space is made by NASA

                          http://www.bbc.co.uk/news/blogs-trending-30210230

                          It's even a great south asian restaurant if you happen to be in the area

                          "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                          ~Napoleon Bonaparte

                          On a crusade to banish setIndexWidget() from the holy land of Qt

                          1 Reply Last reply
                          0
                          • kshegunovK kshegunov

                            Well, as this is the lounge (we are only missing the coffee machines) consider yourself asked. :)

                            JonBJ Offline
                            JonBJ Offline
                            JonB
                            wrote on last edited by
                            #16

                            @kshegunov , and other physicists:
                            OK then. 2 initial quantum questions:

                            1. What does the empirical demonstration of Bell's Inequality Theorem thing tell me about the physical world I inhabit?

                            2. So what actually happened when they did the experiment on Schrödinger's cat?

                            kshegunovK 1 Reply Last reply
                            0
                            • JonBJ JonB

                              @kshegunov , and other physicists:
                              OK then. 2 initial quantum questions:

                              1. What does the empirical demonstration of Bell's Inequality Theorem thing tell me about the physical world I inhabit?

                              2. So what actually happened when they did the experiment on Schrödinger's cat?

                              kshegunovK Offline
                              kshegunovK Offline
                              kshegunov
                              Moderators
                              wrote on last edited by
                              #17

                              @JNBarchan said in @kshegunov Quantum Mechanics:

                              1. What does the empirical demonstration of Bell's Inequality Theorem thing tell me about the physical world I inhabit?

                              Not much as far as I know. Just that there can be no hidden variables in a quantum-like theory. Can't elaborate much on it as I'm not that familiar with the whole formalism.

                              1. So what actually happened when they did the experiment on Schrödinger's cat?

                              As with any thought experiment - at the end of it they got a headache ;)

                              The cat is just an metaphor that tries to illustrate the principle of superposition in QM, but many people fundamentally misunderstand it and think it's bizarre and/or wrong. Basically it boils down to a very simple idea - you have a system with 2 pure states (i.e. the cat is alive, or the cat is dead, you could make the argument with the electron spin all the same). In the closed system where there's no interaction with the outside world the state is a superposition of the two with some probability. When you measure you're no longer dealing with a closed system, that is the person/instrument that measures influences the system, and since there's now determinism involved (i.e. the act of measurement) the state of the system collapses to one of the pure states - the cat is either dead or alive.

                              Read and abide by the Qt Code of Conduct

                              JonBJ 1 Reply Last reply
                              2
                              • kshegunovK kshegunov

                                @JNBarchan said in @kshegunov Quantum Mechanics:

                                1. What does the empirical demonstration of Bell's Inequality Theorem thing tell me about the physical world I inhabit?

                                Not much as far as I know. Just that there can be no hidden variables in a quantum-like theory. Can't elaborate much on it as I'm not that familiar with the whole formalism.

                                1. So what actually happened when they did the experiment on Schrödinger's cat?

                                As with any thought experiment - at the end of it they got a headache ;)

                                The cat is just an metaphor that tries to illustrate the principle of superposition in QM, but many people fundamentally misunderstand it and think it's bizarre and/or wrong. Basically it boils down to a very simple idea - you have a system with 2 pure states (i.e. the cat is alive, or the cat is dead, you could make the argument with the electron spin all the same). In the closed system where there's no interaction with the outside world the state is a superposition of the two with some probability. When you measure you're no longer dealing with a closed system, that is the person/instrument that measures influences the system, and since there's now determinism involved (i.e. the act of measurement) the state of the system collapses to one of the pure states - the cat is either dead or alive.

                                JonBJ Offline
                                JonBJ Offline
                                JonB
                                wrote on last edited by JonB
                                #18

                                @kshegunov
                                Hi,

                                I understand the Schrödinger cat idea, I don't think it's wrong. I just want to know which way it did actually turn out when opened the box on his cat?

                                For the Bell/EPR thing, it's the implication of the "can be no hidden variables" that's intriguing, don't you think? What could quantum entanglement be? Are you more of a "Mathematical Physicist" rather than a "Philosophical Physicist"? ;-)

                                kshegunovK 1 Reply Last reply
                                0
                                • JonBJ JonB

                                  @kshegunov
                                  Hi,

                                  I understand the Schrödinger cat idea, I don't think it's wrong. I just want to know which way it did actually turn out when opened the box on his cat?

                                  For the Bell/EPR thing, it's the implication of the "can be no hidden variables" that's intriguing, don't you think? What could quantum entanglement be? Are you more of a "Mathematical Physicist" rather than a "Philosophical Physicist"? ;-)

                                  kshegunovK Offline
                                  kshegunovK Offline
                                  kshegunov
                                  Moderators
                                  wrote on last edited by
                                  #19

                                  @JNBarchan said in @kshegunov Quantum Mechanics:

                                  I just want to know which way it did actually turn out when opened the box on his cat?

                                  Well, either one way or the other. :)
                                  The point is you can't tell until you open the box.

                                  For the Bell/EPR thing, it's the implication of the "can be no hidden variables" that's intriguing, don't you think?

                                  I guess. I wouldn't trust theories that depend on hidden variables anyway, though. The whole point of science is to learn things, if we argue there exist things that can be neither measured, known or are otherwise hidden, we might as well go to church instead.

                                  What could quantum entanglement be?

                                  State coupling, which is pretty common. The typical (and quite known) problem, however, is not with entanglement itself. It's with the fact the QM is non-local, this mean everything (every process in QM) happens instantaneously in the whole of space, which is bizarre and hard to reconcile with.

                                  Are you more of a "Mathematical Physicist" rather than a "Philosophical Physicist"?

                                  Nuclear theory. Probably you could say I'm more of a mathematical physicist, I enjoy philosophy but am ultimately a practical man.

                                  Read and abide by the Qt Code of Conduct

                                  JonBJ 1 Reply Last reply
                                  0
                                  • kshegunovK kshegunov

                                    @JNBarchan said in @kshegunov Quantum Mechanics:

                                    I just want to know which way it did actually turn out when opened the box on his cat?

                                    Well, either one way or the other. :)
                                    The point is you can't tell until you open the box.

                                    For the Bell/EPR thing, it's the implication of the "can be no hidden variables" that's intriguing, don't you think?

                                    I guess. I wouldn't trust theories that depend on hidden variables anyway, though. The whole point of science is to learn things, if we argue there exist things that can be neither measured, known or are otherwise hidden, we might as well go to church instead.

                                    What could quantum entanglement be?

                                    State coupling, which is pretty common. The typical (and quite known) problem, however, is not with entanglement itself. It's with the fact the QM is non-local, this mean everything (every process in QM) happens instantaneously in the whole of space, which is bizarre and hard to reconcile with.

                                    Are you more of a "Mathematical Physicist" rather than a "Philosophical Physicist"?

                                    Nuclear theory. Probably you could say I'm more of a mathematical physicist, I enjoy philosophy but am ultimately a practical man.

                                    JonBJ Offline
                                    JonBJ Offline
                                    JonB
                                    wrote on last edited by JonB
                                    #20

                                    @kshegunov

                                    It's with the fact the QM is non-local, this mean everything (every process in QM) happens instantaneously in the whole of space, which is bizarre and hard to reconcile with.

                                    That's the bit I mean. And I assume a particle could in principle entangle with many others, and then any of them could influence it at the opposite side of The Universe. When they discover one day, I wonder what the "mechanism" will turn out to be....

                                    Probably you could say I'm more of a mathematical physicist, I enjoy philosophy but am ultimately a practical man.

                                    Yes I kind of guessed :) Being a layman, I am of course a purely philosophical amateur physicist!

                                    Nuclear theory.

                                    Ah ha! That's more like it! Right then: why haven't you figured practical nuclear fusion yet for the world's needs? You've had enough time now!

                                    kshegunovK 1 Reply Last reply
                                    0
                                    • JonBJ JonB

                                      @kshegunov

                                      It's with the fact the QM is non-local, this mean everything (every process in QM) happens instantaneously in the whole of space, which is bizarre and hard to reconcile with.

                                      That's the bit I mean. And I assume a particle could in principle entangle with many others, and then any of them could influence it at the opposite side of The Universe. When they discover one day, I wonder what the "mechanism" will turn out to be....

                                      Probably you could say I'm more of a mathematical physicist, I enjoy philosophy but am ultimately a practical man.

                                      Yes I kind of guessed :) Being a layman, I am of course a purely philosophical amateur physicist!

                                      Nuclear theory.

                                      Ah ha! That's more like it! Right then: why haven't you figured practical nuclear fusion yet for the world's needs? You've had enough time now!

                                      kshegunovK Offline
                                      kshegunovK Offline
                                      kshegunov
                                      Moderators
                                      wrote on last edited by
                                      #21

                                      @JNBarchan said in @kshegunov Quantum Mechanics:

                                      That's the bit I mean. And I assume a particle could in principle entangle with many others, and then any of them could influence it at the opposite side of The Universe. When they discover one day, I wonder what the "mechanism" will turn out to be....

                                      Yes, in principle it could. A group of Chinese scientists farily recently entangled two ensembles (please don't ask me to dig up the article it's quite late). Probably they'd discover QM is just an approximation ... just like what happened with classical mechanics and the relativistic corrections.

                                      Yes I kind of guessed :) Being a layman, I am of course a purely philosophical amateur physicist!

                                      No harm in that. :)

                                      Ah ha! That's more like it! Right then: why haven't you figured nuclear fission yet for the world's needs? You've had enough time now!

                                      Well I had a colleague that was working on that, he went into the private sector - there's just little money in science. Also we have figured it out ages ago, the problem is an engineering one, not a physical. For this you can ask the engineers around ... @Wieland, don't hide, why haven't you built the damn reactor already?! ;)

                                      Read and abide by the Qt Code of Conduct

                                      JonBJ 1 Reply Last reply
                                      1
                                      • kshegunovK kshegunov

                                        @JNBarchan said in @kshegunov Quantum Mechanics:

                                        That's the bit I mean. And I assume a particle could in principle entangle with many others, and then any of them could influence it at the opposite side of The Universe. When they discover one day, I wonder what the "mechanism" will turn out to be....

                                        Yes, in principle it could. A group of Chinese scientists farily recently entangled two ensembles (please don't ask me to dig up the article it's quite late). Probably they'd discover QM is just an approximation ... just like what happened with classical mechanics and the relativistic corrections.

                                        Yes I kind of guessed :) Being a layman, I am of course a purely philosophical amateur physicist!

                                        No harm in that. :)

                                        Ah ha! That's more like it! Right then: why haven't you figured nuclear fission yet for the world's needs? You've had enough time now!

                                        Well I had a colleague that was working on that, he went into the private sector - there's just little money in science. Also we have figured it out ages ago, the problem is an engineering one, not a physical. For this you can ask the engineers around ... @Wieland, don't hide, why haven't you built the damn reactor already?! ;)

                                        JonBJ Offline
                                        JonBJ Offline
                                        JonB
                                        wrote on last edited by JonB
                                        #22

                                        @kshegunov

                                        Ah ha! That's more like it! Right then: why haven't you figured nuclear fission yet for the world's needs? You've had enough time now!

                                        You quoted me before I had changed "fission" to "fusion", which is embarrassing! [Although it would be one way to solve all our needs :) ] I had also changed it to "practical nuclear fusion".

                                        So once it's "practical" you hand over to engineers?! It's their problem. What about you come with some nuclear science physics which aids the practicalities? I don't know, find I way to make it work much closer to room temperature, or with less need for input power? :) We have been waiting for like 50 years for this promised physics + technology, and it's always "20-odd years away".

                                        kshegunovK 1 Reply Last reply
                                        0
                                        • JonBJ JonB

                                          @kshegunov

                                          Ah ha! That's more like it! Right then: why haven't you figured nuclear fission yet for the world's needs? You've had enough time now!

                                          You quoted me before I had changed "fission" to "fusion", which is embarrassing! [Although it would be one way to solve all our needs :) ] I had also changed it to "practical nuclear fusion".

                                          So once it's "practical" you hand over to engineers?! It's their problem. What about you come with some nuclear science physics which aids the practicalities? I don't know, find I way to make it work much closer to room temperature, or with less need for input power? :) We have been waiting for like 50 years for this promised physics + technology, and it's always "20-odd years away".

                                          kshegunovK Offline
                                          kshegunovK Offline
                                          kshegunov
                                          Moderators
                                          wrote on last edited by
                                          #23

                                          @JNBarchan said in @kshegunov Quantum Mechanics:

                                          So once it's "practical" you hand over to engineers?!

                                          It was just a jape.

                                          What about you come with some nuclear science physics which aids the practicalities?

                                          As far as I know, although it isn't my subspecialty, they're building a reactor currently in germany to test some ideas. They are hopeful, but you know ... we don't sell any guarantees ...

                                          We have been waiting for like 50 years for this promised physics + technology, and it's always "20-odd years away".

                                          That's what I told my colleague while he was still working on it. He replied he doubts it'd be less than 50 years before we actually have a real and industry grade solution on that.

                                          Read and abide by the Qt Code of Conduct

                                          JonBJ 1 Reply Last reply
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