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  1. Sure, there are many ways to do this. Momentum is defined to be the derivative of the Lagrangian with respect to velocity, i.e. it describes how kinetic energy relates to relative velocity, as a function of rest mass - this is simply a generalisation of the good old p=mv, as we all know it from our school days: \[p^{\mu } =\frac{\partial L}{\partial v^{\mu }} =mu^{\mu }\] with the Lagrangian for relativistic motion being \[L=-mc\int ds=-mc\int \sqrt{\eta _{\mu \nu } dx^{\mu } dx^{\nu }}\] Energy, on the other hand, is defined as \[E=p^{\mu } v_{\mu } -L\] which is in essence a restatement of the fact that energy is the conserved quantity that arises from time-translation invariance in spacetime (see Noether‘s theorem for formal proof). Put these together and rearrange to get \[E=\sqrt{m^{2} c^{4} +p^{2} c^{2}}\] as stated above. You could also simply look at the general form of a 4-momentum vector, and see immediately that its temporal and spatial parts are related as above. This would be a standard way to derive this, but there are many, many other ways to do this, both informally and in very formal ways. For massive particles at rest you have m<>0 and p=0 - insert into the above to get \[E=mc^2\] as requested. You can also derive all of this from first principles - the symmetries of Minkowski spacetime - in a very formal way by using Noether‘s theorem; this gives you the energy-momentum tensor as a conserved quantity, and from its vanishing divergence you can derive the above expression as well. The problem here isn‘t any of the above, because you can find all of this in pretty much any standard undergrad text on Special Relativity. This is basic stuff, and it is not in contention. The problem though is that your response to this will be along the lines of: “You don’t understand anything, you are just parroting what you have read!”. Am I right?
    2 points
  2. What help do you need or want? In order to help you we need to know what you already understand about this problem, what you are able to do, and what you are not able to do. In order to know that, we need to see what you have tried yourself. Surely you did not just post this without trying at all yourself? Please show us what you have tried.
    1 point
  3. The full energy-momentum relation (which is simply the relationship between the temporal and spatial parts of the 4-momentum vector) is \[E=\sqrt{m^2c^4+c^2p^2}\] For massive particles at rest you have p=0 and thus \[E=mc^2\] For photons you have m=0, and thus \[E=pc\] Particles do not need to be stable in order to be elementary. For example, the muon is elementary, but has only a short lifetime. Protons don't decay, so it is "more stable" than the neutron - even though both of them are quark triplets. Neutrinos naturally arise from the way the weak interaction works, since energy and momentum need to be conserved. Protons are not fundamental, they are composed of quark triplets, same as neutrons. They do interact with matter, it's called the Mikheyev-Smirnov-Wolfenstein effect. They also interact gravitationally, if you have enough of them. Gravity is not a force (though it can be approximated as such in the Newtonian limit) - as is easily seen by going into free fall while carrying an accelerometer.
    1 point
  4. I do not understand where you addressed this: The distance to Venus is more than one light minute. Distance to celestial bodies can be measured with experiments based on parallax and such a measurement relies on rather basic trigonometry. If your claim is right then every measurement of for instance distance from earth to Venus and earth to sun are wrong? Please provide a detailed explanation why you reject the results of basic geometry. Please include necessary mathematics to explain your version of parallax measurements. Does that matter? When someone shows enough interest in your thread to actually read it, compare the facts with established theories, try to draw conclusions and then ask for followup information it could be in your interest to try to answer and clarify rather than complain, repeat or add unrelated information?
    1 point
  5. We owe a lot to that partnership. I believe there is still a lot we could gain from it, that its perhaps an essential connection for humanity to our environment, being lost with the divorce of canine development and evolution from environmental demands.
    1 point
  6. That was a huge block of text entering into many areas which only have a tenuous connection or none at all. So many questions all at once, I can't tell which are important to you so here are a few thoughts. Phlogiston was not a 'force' theory. You are correct that it takes a finite time for a photon to interact with an atom or electron or for the generation of a photon from an atom or electron. This interaction time does not determine the energy of the interaction in any way. It is related to the energy by the Heisenberg uncertainty principle (HUP). The quantum of energy is determined by environmental factors which set the potential energy levels available to the system. If you can separate out and organise your questions better you will get some better answers.
    1 point
  7. ESA has an introduction about CubeSats. This information seems not very biased towards a specific manufacturer: Source: https://www.esa.int/Enabling_Support/Preparing_for_the_Future/Discovery_and_Preparation/CubeSats The form factor of a CubeSat allows them to be stacked and placed in unused space in a launch vehicle.
    1 point
  8. ! Moderator Note It's also NOT in the spirit of the religion section of a science discussion forum. You are clearly preaching here, telling us there is only one way to think, and that's against the rules. If you want to make claims like that here, then you have to show evidence to support your ideas. More than hand waiving, more than yelling from a soapbox. Either stop making the claims or start supporting them. You have some people interested in talking to you, but they'll start reporting you if you don't follow the rules.
    1 point
  9. If you have circular polarization, this is associated with the photon having spin angular momentum of ±hbar. Changing this value is not associated with the wavelength.
    1 point
  10. AlexandrKushnirtshuk refuses to even attempt to give answers to any questions. Seems like it is time to close this...
    0 points
  11. I browsed through that source site of your revelations for about 120 seconds and I'm surprised your thread is not yet locked and trashed. The 3 pages of utter BS you post in this thread, without any science, evidence of any sort or even a trace of scientific sanity is frankly scary.
    0 points
  12. Here is accurate representation of the Relative sizes and distance between the Earth and Moon. Given the apparent size of the Earth in the photo, the light from the Sun and the date (which would make it a new moon). I estimate that the Moon should be just about where the object labeled Mercury is in this image. In other words, "Mercury" is mislabeled, The picture shows the Earth, Venus and the Moon, while Mercury is out of frame. It is just the angle from which this photo was taken and telescopic foreshortening that makes Venus "look" closer to the Earth than the Moon is.
    0 points
  13. 1) New model of the Universe. 2) The nature of light and the size of the Universe. That animation is cut off about 12 hours at about 07:00 a.m. (2012 july 23). No data (photos) from about 07:00 till about 19:00 on that animation in the link you provided.
    -2 points
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