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From: Y.Porat on 17 Apr 2010 03:24 On Apr 7, 3:17 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Apr 6, 10:33 pm, Tony M <marc...(a)gmail.com> wrote: > > > > > On Apr 6, 3:22 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Apr 6, 7:58 am, Tony M <marc...(a)gmail.com> wrote: > > > > > On Apr 5, 2:40 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Apr 5, 1:35 pm, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > > > > > > > On Apr 5, 2:18 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Apr 4, 12:53 am, Koobee Wublee <koobee.wub...(a)gmail.com> wrote: > > > > > > > > > On Apr 3, 10:23 pm, Tom Roberts wrote: > > > > > > > > > > Tony M wrote: > > > > > > > > > > As per the mass-energy equivalence, can I assume the following is > > > > > > > > > > valid? > > > > > > > > > > In relativity, which I assume is the context for your question, mass and energy > > > > > > > > > are not "equivalent" in the manner you seem to think. They are in certain > > > > > > > > > circumstances inter-convertible, but are most definitely not the same. > > > > > > > > > This is unbelievable. Self-styled physicists came up with (E = m > > > > > > > > c^2). Now, they are walking away from it and speak with a forked > > > > > > > > tongue. These clowns are very liberally interpreting the scripture > > > > > > > > according to their religion. That's what you get for liberal-art > > > > > > > > schools, I guess. <shrug> > > > > > > > > E=mc^2 in no way implies that mass and energy are equivalent, any more > > > > > > > than F=ma implies that force and acceleration are equivalent. > > > > > > > > The equation relates the quantitative values of two distinct physical > > > > > > > variables. That's what equations do. > > > > > > > > If you cannot read an equation, then perhaps you should read some > > > > > > > sentences that precede and follow the equation where it is presented. > > > > > > > <<...an electron and a positron, each with a mass > > > > > > of 0.511 MeV/c2, can annihilate to yield 1.022 MeV of energy.>>http://en.wikipedia.org/wiki/Electronvolt > > > > > > > Sue... > > > > > > Yes, indeed. There is the numerical equality I was talking about. Note > > > > > that a processes where the collision of two objects with mass produces > > > > > a predictable amount of energy does not imply that mass and energy are > > > > > equivalent. Perhaps you have the same difficulty that KW is having.- Hide quoted text - > > > > > > - Show quoted text - > > > > > I think you're right PD, mass and energy are not the same thing. Maybe > > > > "equivalence" is not the best word, "duality" is probably better. The > > > > way I see it, mass and energy are two sides of the same coin, one > > > > cannot convert mass to energy and vice-versa. For a certain amount of > > > > energy in a system there will always be a corresponding amount of > > > > mass, as per E=mc2. > > > > > Sue's example of electron-positron "annihilation" can be a bit > > > > misleading, making one believe that mass gets converted to energy, > > > > when that's not the case. The isolated system consisting of the > > > > electron and positron has the same total energy and corresponding mass > > > > before and after the "annihilation", except now instead of electron > > > > and positron we have gamma photons (and maybe some other particles).. > > > > One must be a little bit careful about the meaning of mass here. > > > The invariant mass of the system (m^2 = E^2 - p^2) is indeed ... > > > well ... invariant, but you'll notice this quantity is not the > > > summative mass, namely the sum of the rest masses of the particles > > > involved. Where mass-energy conversion takes place, it is summative > > > mass that is usually being referred to. > > > Yes PD, one must be careful about the meaning of mass, especially when > > talking about "rest" or "invariant" mass. This will surely confuse a > > lot of people. One must keep in mind that there is ONLY ONE MASS. The > > problem is that the VALUE of that one mass is observer dependent. In > > order to provide a common ground for all the observers scientists have > > defined these standard frames of reference. If everyone measures the > > mass in the same standard frame of reference then they will all get > > the same value. For the "rest" mass (which applies to one particle) > > the frame of reference is at rest with that particle. The "invariant" > > mass applies to systems of particles and is defined in the frame of > > reference in which the system is at rest, even though individual > > particles in the system are not. But we know there is no preferred > > frame of reference in relativity, and it's postulated that all the > > laws of physics are the same in any of them, so these standardized > > frames are no more special than the infinite number of other frames of > > reference one can choose. (I'm talking about inertial frames in SR > > here.) The equation E = m c^2 IS the general form for the TOTAL ENERGY > > in any arbitrary frame of reference, where m is the relativistic mass > > in that frame of reference. > > Well, perhaps this is being pedantic, but I would quibble with your > claim that there is only one mass and that that one mass is the > relativistic mass. This is precisely what has gone out of disfavor in > recent decades. ---------------- the idiot PD still ddint get that there is JUST ONE KIND OF MASS!! AND IT IS NOT RELATIVISTIC BECAUSE IN E=MC^2 there is no GAMMA FACTOR TO MAKE IT 'RELATIVISTIC!! the gamma factor DOES NOT APPLY TO THE PHOTON !! therefore not to energy !!! will you stick it once and for all into your tough skull ??? one of the great disasters that was inflicted on physics since more than the last half century is that dumb mathematicians took over physics !! Y.Porat -------------------------------
From: Y.Porat on 17 Apr 2010 03:32 On Apr 11, 4:38 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: > franklinhu wrote: > > The energy which is actually conserved is the kinetic energy gained by > > the positron and electron as they are accelerated to the speed of > > light as they collide. > > I specified annihilation at rest, as it is simpler. There is no such > "acceleration to the speed of light"; they come together and annihilate. The > initial state is an e+ and an e- at rest and close together; the final state is > two 0.511 keV gammas headed off in opposite directions at the speed of light > (all measured relative to the initial rest frame of the e+ and the e-). > > The total mass in the initial state is 1.022 MeV/c^2, and the total kinetic > energy is 0. The total mass in the final state is 0 and the total kinetic energy > is 1.022 MeV. That numerical equality is not happenstance, and we say "mass was > converted into kinetic energy", because that is the way these words are used. > > > The original positron and > > electron are not destroyed. > > Not true -- they are OBSERVED to be gone. > > > They are instead converted into a nearly > > impossible to detect neutral particle. > > This is just plain not true. If there were such a particle in the final state, > with a mass of 1.022 MeV/c^2 (as you seem to claim), it WOULD be detected > through failure of energy to be conserved. > > > Explain me one thing - just how does matter turn into energy and how > > does energy turn into matter? Can't explain that, can you - no one > > can. > > Right. Humans will always be unable to "explain" how nature actually works. We > are limited by our minds, which process only thoughts. All we can do is process > thoughts that are MODELS of what we observe about the world we inhabit. This is > inherent in being human. Live with it (you have no choice). > > Tom Roberts -------------------- 'quote( from Roberts the idot **demagogue mumbler ** ) ''> Right. Humans will always be unable to "explain" how nature actually works. end of quote better speak for yourself !!! would you believe that Tom Roberts is a member of the sci.physics.research ?? (:-) (and that s how it looks like !!!) Y.Porat -----------------------------
From: Autymn D. C. on 17 Apr 2010 06:18 On Apr 11, 9:57 pm, franklinhu <frankli...(a)yahoo.com> wrote: > I would predict that the quantative reaction rate would be similar if > not identical to what we observe for neutrinos. In my model, neutrinos > are a specific wave energy phenonmenon similar to photons except they > act on single poselectron particles much like how a string a billiard > balls react when struck at one end. A poselectron particle passing > through a poselectron aether would be like detecting a single molecule > of oxygen zipping about a room of air. However, it would still carry a > significant kinetic energy and there will be some small chance that it > will release that energy upon some other particle and create a > detectable particle shower. It could be a neutrino is actually just a > rapidly moving poselectron. Unfortunately, it may mean that you would rapidly -> swiftly move -> draw, drag, drift, drive, fare, go, shift, budge, stir... You never read my posts. Neutrinos are not energhy quanta--they are leptomesòns, two- or three-body sýstems with hihher harmonics, and belong above (or below, in my build) protium/hydrogen in the ecsotic group of the perihodic tabul of elements. Cosmic "wimps" (Weak is such a misnomer as it means not well, or near death, whereas not strong is limp.) would stell beside them to make a full shell. PDG fellows still don't know the structure of neutral leptòns but I do! -Aut
From: Autymn D. C. on 17 Apr 2010 06:54 On Apr 12, 8:31 am, Tom Roberts <tjrob...(a)sbcglobal.net> wrote: > Note also that in relativity there is no possible amount of "acceleration" that > will get them to "gain the speed of light prior to collision". Note also thas in wave mekanics and a few of my old posts, any slower harmonic of celerity becomes the same as celerity for a givven test band where a mote's de Broglie wave is incoherent with the test radiation. -Aut
From: Autymn D. C. on 17 Apr 2010 07:00 On Apr 14, 1:48 pm, spudnik <Space...(a)hotmail.com> wrote: > thus: > darn; I thought, from the header, > you were using a multiplier of 7 ... and that > made me realize, the professors who do that, > are subverting the "big Oh" and "little oh" formalism. There is no h in O or o. Sizes go as a littel, a bit, a fitt, a lot, and a mickel. Do not call O and o by sizes; they aren't the same vowel.
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