Johnny5

That article is well written, thank you. Well from memory the Schrodinger equation is: [math] \frac{-\hbar}{2M} \nabla^2 \Psi + U \Psi = i \hbar \frac{\partial \Psi}{\partial t} [/math] The reason I start here, is because I have used the equation above to derive the spherical harmonics for the hydrogen atom before. I used separation of variables. In the solution, M was the reduced mass. I still have all the mathematical work which went into the solution. The wikipedia article starts out with the Schrodinger equation in a different form, it uses the 'bra' 'ket' notation, due to Dirac, which came years after Shrodinger formulated his equation. I think schrodinger wanted psi to represent energy density if I am not mistaken, and it was Born's idea to interpret psi times the complex conjugate of psi as related to the probability of the particles being in some region of space. You asked for me to ask a question. I guess the intelligent first question to ask is, what mass does the letter m denote, in the first equation at the wikipedia site? First of all I am already uncomfortable using the first equation at the wikipedia site, because it is not the one I derived the spherical harmonics of a hydrogen atom with. I don't immediately see the equivalence of it to the equation I have. (Perhaps demonstrating equivalence would be a good place to start) I can see that the first term of the operator there represents "kinetic energy" the second term of the operator represents the potentially kinetic energy, and the operator operates on [math] | \Psi (t) > [/math], you would have to be blind not to notice that. I see a whole lot of differences between the equation I am familiar with, and the starting point there. I can make a small adjustment to the original Schrodinger equation as follows: [math] [\frac{-\hbar}{2M} \nabla^2 + U ]\Psi = i \hbar \frac{\partial \Psi}{\partial t} [/math] That starts off demonstrating equivalence, but of course the wikipedia site is already using the 'bra' 'ket' notation, which is highly abstract, not to mention anachronistic. Regards

What on earth are you trying to show me? It would help me follow you, if you actually derived the formula we are talking about from your starting point. Regards

Yeah I thought so, so let me ask you this. Suppose I am a source which is going to "push" the thing in the direction which is tangent to the elliptical orbit this thing finally takes on. I would have to "push" perfectly to get the orbit to be elliptical. Not enough push would mean the things spiral together, and too much would mean they sail away from each other. So how is it that nature managed to get things perfect? Do you know? Regards

Oh this answer is excellent, because I see you clearly understand the question. I think in fact there is a reason, and it goes back to the finite discrete difference calculus, which the differential calculus is based upon. Let me explain. Consider the difference operator: [math] \Delta Q = Q2-Q1 [/math] Here we see that the idea of change in the difference calculus is based upon subtraction, where Q denotes some quantity of physics. In order to have delta Q be nonzero, time has to increment or decrement. Now, if we stipulate that Q2 is measured after Q1 is measured, or even better yet stipulate that Q2 is the value of Q after Q1 is the value of Q, then we have inserted the unidirectionality of time into our mathematics haven't we? I mean this is my whole question. The moment Q takes on its value Q2 and the moment Q takes on its value Q1 aren't the same moment in time. Necessarily, one moment must come before the other. By convention Q2 is the value of Q later in time. So doesn't this convention "stipulate" that time flows unidirectionally? Recall that the definition of the derivative is based upon the difference operator.

Have you ever seen the kind of derivation I am asking about? Regards

The number of bodies is finite, the inertial mass per body is finite, hence the total inertial mass of the universe is finite, hence the total energy is finite. Regards

Why on earth not? It makes total intuitive sense, it's practically obvious to me now. I guess you could say that in my model, vacuum cannot be created, hence was always there. Using that model of vacuum, it makes sense to say that somewhere in the universe is the center of mass of the universe. Regards

I don't like the hydrino idea, the originator of it has no understanding of physics, he was a doctor, not a physicist. Night and day. I've seen the blacklight thing before, I pay no attention to it, I don't waste my time with it. I am positive that if i were to ask him simple questions, he would get them wrong. But thank you for showing me the link. I don't really see how any of this gets to the heart of the matter though, which is does the universe have a center of inertia or not. Why doesn't anyone seem to 'know' the answer? Regards

It did yesterday, I will try to find another. Regards

Thanks, but I wanted someone who already knows it to explain it. Regards

That all depends on who frequents the board. It's one of several things I am currently interested in. Also it's a good way to find people with similar interests. I could read a book on it, but its more enjoyable to interact with a person who already has the knowledge you seek. Regards

Well exactly how have you reached the conclusion that the formula for relativistic mass is true? Regards

The energy of a photon (which is a particle of light) is given by the following formula, in the rest frame of a laser: [math] E = hf [/math] The symbol h denotes Planck's temporal constant of nature. That means that its difference taken over any two consecutive moments in time must be zero, i.e. [math] \Delta h = 0 [/math] The symbol f denotes the frequency of the photon, and this varies from photon to photon. The point is, since photons are particles, and their energy is given by the quantum mechanical relation above, it certainly is possible to calculuate the energy of a particle. Regards

Being pretty confident, isn't being certain. The simplest way to prove that the second postulate leads to a contradiction, is to prove that simultaneity is absolute not relative. The barn and ladder problem does this perfectly. Regards

Suppose that a spaceship is initially at rest with respect to me. Then, the spaceship accelerates off in some direction trying to reach the speed of light. As I understand it, the time dilation formula tells me that the accelerated ship will experience time dilation interior to it. According to the formula, that means that time will slow down inside the ship. That means that things will appear to move in slow motion, until (at the speed of light) all motion inside the ship would stop. Isn't this the condition for the ship to be at a temperature absolute zero degrees? Time and temperature aren't related in this manner are they? And one more thought... if the time dilation effect is relative, then when his ship reaches the speed of light, is my temperature absolute zero degrees? Regards

What is the fastest proof of the Pythagorean theorem in the world? Thank you J5

I am interested in learning quantum field theory as fast as possible. Is there anyone here who can help me learn it quickly? Assume that I already know classical electrodynamics. Thank you

Well I would enjoy seeing just one of your five proofs, because they aren't equal. In fact, 1 is a number, and .99999... isn't a number, so your proof is guaranteed to contain an error, you will equate apples to oranges, which is similiar to adding apples and oranges, but not identical. I'm not playing semantical games either. In this particular problem, semantics happens to matter. Regards

Suppose that I have two particles in vacuum, and there is only one interaction force between them, and that force is a central force. Assume that at the beginning of time, the particles are a distance R apart, but are being pulled together by this one superforce S. How can I get the particles to orbit one another. Won't they just head right for the center of mass of the universe, collide, and then reflect or something in linear motion rather than circular motion? Put another way, exactly how does a central force end up making things orbit the center of mass. Regards

Suppose that I wanted to model the universe as a collection of an integral number of bodies, and then intelligently discuss changes in the state of the universe. Suppose I choose to represent the state of the universe by the symbol [math] \Psi [/math]. Now I want to focus on a single change of the state of the universe, which I will represent using: [math] \Delta \Psi [/math] Here is my question. Why would it be wrong to say that the state of the universe has changed if and only if the center of inertia of at least one object moved relative to the center of inertia of another? Regards

Severian, photons do have rest frames. I suggest you try to derive the equation for total energy yourself. See the other thread. Regards

Thank you Pangloss, but my question really wasn't answered. I just want to know whether or not the universe has a center. It exploded into pure vacuum, so I think there is one, but how would you go about proving that it has one experimentally. <-- That's the question I want answered. Thank you