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From: Inertial on 1 Jan 2010 05:21 "Y.Porat" <y.y.porat(a)gmail.com> wrote in message news:2c7de598-5bc2-47cc-b923-04afde4c7d25(a)d20g2000yqh.googlegroups.com... > On Dec 31 2009, 9:21 pm, PD <thedraperfam...(a)gmail.com> wrote: >> On Dec 26, 5:42 pm, Spencer Spindrift >> >> <spencerspindr...(a)btinternet.com> wrote: >> > Q.: How is it that a photon has momentum but no mass? >> > Or in other words how does light carry energy? >> > As far as I know momentum is a property of moving or spinning >> > mass. >> > A photon cannot have mass or it would be infinite at C.. >> >> > A.; ??? >> >> If you've been led to believe that momentum is a property of a moving >> mass and SOLELY a moving mass, then you've been misled. >> It is often stated that FOR a moving mass, the momentum is defined as >> mass x velocity. >> This turns out also to be a lie. >> >> First of all, it's not a definition, it's an empirically derived rule. >> >> Secondly, it's not right, though it works very well at low velocities. >> At higher velocities, you have to use gamma x mass x velocity, where >> gamma is a number that is darn close to 1 for low speeds but gets >> bigger and bigger as you get to an appreciable fraction of the speed >> of light. > -------------------------- > and who the hell told you that this Gamma > is attached to the mass?? As has been explained to you countless times .. it is NOT attached to anything > just because you understand only algebra parroting ??? > and evn by algebra that you understand You clearly do not understand math or algebra > how about > instead of > momentum = gamma m v > > Momentum /gamma = m v Same thing > in that case you dont have to **Invent*** > a new kind of mass !!!!!! There was no invention of a new kind of mass > **and m re,mains constant !!!??? It always was constant > how about thinking physics > and not parroting You're not thinking at all > btw > as for the photon > THE GAMMA FACTOR DOES NOT APPLY AT ALL TO IT !! Why .. does it have some of special anti-gamma-factor shield? > it is another indication about the need to know > were and how to use it !!! You don't > 9bacause of ambiguity situations !!! > -------------- > > > >> >> Third, this rule ONLY applies for moving masses, and should not be >> used for just anything that has momentum. Other entities also carry >> momentum but not described by that rule. >> >> In the end, what momentum is, is whatever quantity can be ascribed to >> a physical entity such that the total of that quantity for all objects >> of all kinds in a closed system is constant. It's still remarkable >> that such a rule can be found at all. >> --------------------- > > (:-) > Hi abstract philosopher !! > ps > excuse me PD for 'leeching' on you > but you can see that i bring physics > arguments !! No .. not a word of rational physics there.
From: Y.Porat on 1 Jan 2010 05:40 On Jan 1, 12:21 pm, "Inertial" <relativ...(a)rest.com> wrote: > "Y.Porat" <y.y.po...(a)gmail.com> wrote in message > > news:2c7de598-5bc2-47cc-b923-04afde4c7d25(a)d20g2000yqh.googlegroups.com... > > > > > On Dec 31 2009, 9:21 pm, PD <thedraperfam...(a)gmail.com> wrote: > >> On Dec 26, 5:42 pm, Spencer Spindrift > > >> <spencerspindr...(a)btinternet.com> wrote: > >> > Q.: How is it that a photon has momentum but no mass? > >> > Or in other words how does light carry energy? > >> > As far as I know momentum is a property of moving or spinning > >> > mass. > >> > A photon cannot have mass or it would be infinite at C.. > > >> > A.; ??? > > >> If you've been led to believe that momentum is a property of a moving > >> mass and SOLELY a moving mass, then you've been misled. > >> It is often stated that FOR a moving mass, the momentum is defined as > >> mass x velocity. > >> This turns out also to be a lie. > > >> First of all, it's not a definition, it's an empirically derived rule. > > >> Secondly, it's not right, though it works very well at low velocities. > >> At higher velocities, you have to use gamma x mass x velocity, where > >> gamma is a number that is darn close to 1 for low speeds but gets > >> bigger and bigger as you get to an appreciable fraction of the speed > >> of light. > > -------------------------- > > and who the hell told you that this Gamma > > is attached to the mass?? > > As has been explained to you countless times .. it is NOT attached to > anything > > > just because you understand only algebra parroting ??? > > and evn by algebra that you understand > > You clearly do not understand math or algebra > > > how about > > instead of > > momentum = gamma m v > > > Momentum /gamma = m v > > Same thing > > > in that case you dont have to **Invent*** > > a new kind of mass !!!!!! > > There was no invention of a new kind of mass > > > **and m re,mains constant !!!??? > > It always was constant > > > how about thinking physics > > and not parroting > > You're not thinking at all > > > btw > > as for the photon > > THE GAMMA FACTOR DOES NOT APPLY AT ALL TO IT !! > > Why .. does it have some of special anti-gamma-factor shield? > > > it is another indication about the need to know > > were and how to use it !!! > > You don't > > > > > 9bacause of ambiguity situations !!! > > -------------- > > >> Third, this rule ONLY applies for moving masses, and should not be > >> used for just anything that has momentum. Other entities also carry > >> momentum but not described by that rule. > > >> In the end, what momentum is, is whatever quantity can be ascribed to > >> a physical entity such that the total of that quantity for all objects > >> of all kinds in a closed system is constant. It's still remarkable > >> that such a rule can be found at all. > >> --------------------- > > > (:-) > > Hi abstract philosopher !! > > ps > > excuse me PD for 'leeching' on you > > but you can see that i bring physics > > arguments !! > > No .. not a word of rational physics there. ---------------------- F.F.F.F. (:-) Y.P ------------------------
From: PD on 1 Jan 2010 13:28 On Jan 1, 3:21 am, "Y.Porat" <y.y.po...(a)gmail.com> wrote: > On Dec 31 2009, 9:21 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > On Dec 26, 5:42 pm, Spencer Spindrift > > > <spencerspindr...(a)btinternet.com> wrote: > > > Q.: How is it that a photon has momentum but no mass? > > > Or in other words how does light carry energy? > > > As far as I know momentum is a property of moving or spinning > > > mass. > > > A photon cannot have mass or it would be infinite at C.. > > > > A.; ??? > > > If you've been led to believe that momentum is a property of a moving > > mass and SOLELY a moving mass, then you've been misled. > > It is often stated that FOR a moving mass, the momentum is defined as > > mass x velocity. > > This turns out also to be a lie. > > > First of all, it's not a definition, it's an empirically derived rule. > > > Secondly, it's not right, though it works very well at low velocities. > > At higher velocities, you have to use gamma x mass x velocity, where > > gamma is a number that is darn close to 1 for low speeds but gets > > bigger and bigger as you get to an appreciable fraction of the speed > > of light. > > -------------------------- > and who the hell told you that this Gamma > is attached to the mass?? It isn't attached to the mass. It's a factor that is included in the expression for momentum of massive objects. That's one of three factors, none of which is "attached" to any of the others. > just because you understand only algebra parroting ??? > and evn by algebra that you understand > > how about > instead of > momentum = gamma m v > > Momentum /gamma = m v > > in that case you dont have to **Invent*** > a new kind of mass !!!!!! Nor am I inventing a new kind of mass here. What I'm doing is writing the CORRECT expression for the momentum of a massive object. > > **and m re,mains constant !!!??? > how about thinking physics > and not parroting > btw > as for the photon > THE GAMMA FACTOR DOES NOT APPLY AT ALL TO IT !! That's correct, and the formula momentum = gamma x mass x velocity doesn't apply to photons at all. A wholly different expression for momentum is used for photons. > it is another indication about the need to know > were and how to use it !!! > 9bacause of ambiguity situations !!! > -------------- > > > > > Third, this rule ONLY applies for moving masses, and should not be > > used for just anything that has momentum. Other entities also carry > > momentum but not described by that rule. > > > In the end, what momentum is, is whatever quantity can be ascribed to > > a physical entity such that the total of that quantity for all objects > > of all kinds in a closed system is constant. It's still remarkable > > that such a rule can be found at all. > > --------------------- > > (:-) > Hi abstract philosopher !! Nothing abstract about it. It's really very straightforward and practical. > ps > excuse me PD for 'leeching' on you > but you can see that i bring physics > arguments !! > ATB > Y.Porat > --------------
From: Inertial on 1 Jan 2010 18:58 "PD" <thedraperfamily(a)gmail.com> wrote in message news:9bc72936-b582-4859-9e20-e36e0e40ca9a(a)c34g2000yqn.googlegroups.com... > On Jan 1, 3:21 am, "Y.Porat" <y.y.po...(a)gmail.com> wrote: >> On Dec 31 2009, 9:21 pm, PD <thedraperfam...(a)gmail.com> wrote: >> >> > On Dec 26, 5:42 pm, Spencer Spindrift >> >> > <spencerspindr...(a)btinternet.com> wrote: >> > > Q.: How is it that a photon has momentum but no mass? >> > > Or in other words how does light carry energy? >> > > As far as I know momentum is a property of moving or spinning >> > > mass. >> > > A photon cannot have mass or it would be infinite at C.. >> >> > > A.; ??? >> >> > If you've been led to believe that momentum is a property of a moving >> > mass and SOLELY a moving mass, then you've been misled. >> > It is often stated that FOR a moving mass, the momentum is defined as >> > mass x velocity. >> > This turns out also to be a lie. >> >> > First of all, it's not a definition, it's an empirically derived rule. >> >> > Secondly, it's not right, though it works very well at low velocities. >> > At higher velocities, you have to use gamma x mass x velocity, where >> > gamma is a number that is darn close to 1 for low speeds but gets >> > bigger and bigger as you get to an appreciable fraction of the speed >> > of light. >> >> -------------------------- >> and who the hell told you that this Gamma >> is attached to the mass?? > > It isn't attached to the mass. It's a factor that is included in the > expression for momentum of massive objects. That's one of three > factors, none of which is "attached" to any of the others. > >> just because you understand only algebra parroting ??? >> and evn by algebra that you understand >> >> how about >> instead of >> momentum = gamma m v >> >> Momentum /gamma = m v >> >> in that case you dont have to **Invent*** >> a new kind of mass !!!!!! > > Nor am I inventing a new kind of mass here. What I'm doing is writing > the CORRECT expression for the momentum of a massive object. > >> >> **and m re,mains constant !!!??? >> how about thinking physics >> and not parroting >> btw >> as for the photon >> THE GAMMA FACTOR DOES NOT APPLY AT ALL TO IT !! > > That's correct, and the formula momentum = gamma x mass x velocity > doesn't apply to photons at all. Not in the form written, as it involves a division by zero and so is indeterminate or infinite. I've explained that to Porat many times before. If you rewrite it as: mass = momentum / gamma / velocity Then the factor of 1/gamma makes the expressions zero so you have mass = 0 Which is, of course, correct for photons. gamma appearing as a multiplier in a formula for something travelling at c will results in infinite or indeterminate values. But it is quite valid to divide by it (which is equivalent to multiplying by zero)
From: Y.Porat on 2 Jan 2010 02:10
On Jan 1, 8:28 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Jan 1, 3:21 am, "Y.Porat" <y.y.po...(a)gmail.com> wrote: > > > > > On Dec 31 2009, 9:21 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Dec 26, 5:42 pm, Spencer Spindrift > > > > <spencerspindr...(a)btinternet.com> wrote: > > > > Q.: How is it that a photon has momentum but no mass? > > > > Or in other words how does light carry energy? > > > > As far as I know momentum is a property of moving or spinning > > > > mass. > > > > A photon cannot have mass or it would be infinite at C... > > > > > A.; ??? > > > > If you've been led to believe that momentum is a property of a moving > > > mass and SOLELY a moving mass, then you've been misled. > > > It is often stated that FOR a moving mass, the momentum is defined as > > > mass x velocity. > > > This turns out also to be a lie. > > > > First of all, it's not a definition, it's an empirically derived rule.. > > > > Secondly, it's not right, though it works very well at low velocities.. > > > At higher velocities, you have to use gamma x mass x velocity, where > > > gamma is a number that is darn close to 1 for low speeds but gets > > > bigger and bigger as you get to an appreciable fraction of the speed > > > of light. > > > -------------------------- > > and who the hell told you that this Gamma > > is attached to the mass?? > > It isn't attached to the mass. It's a factor that is included in the > expression for momentum of massive objects. That's one of three > factors, none of which is "attached" to any of the others. > ------------------ if so it is much better for my claim (:-) we will see later .... > > just because you understand only algebra parroting ??? > > and evn by algebra that you understand > > > how about > > instead of > > momentum = gamma m v > > > Momentum /gamma = m v > > > in that case you dont have to **Invent*** > > a new kind of mass !!!!!! > > Nor am I inventing a new kind of mass here. What I'm doing is writing > the CORRECT expression for the momentum of a massive object. we will see (JUST LATER )that concluding that mass if infalated (based on that) is just an unjustified INTERPRETATION !! > > > > > **and m re,mains constant !!!??? > > how about thinking physics > > and not parroting > > btw > > as for the photon > > THE GAMMA FACTOR DOES NOT APPLY AT ALL TO IT !! > > That's correct, and the formula momentum = gamma x mass x velocity > doesn't apply to photons at all. yes exactly and i always have to argue about it with parrots !! because (among the others ) the photon moves at c andno mare exeleration and V=c is A LIMIT CASE even mathematically not to mention - physically !! anyway lets examine a mass wich moves at the velocity - something less that c just folowing: -------------- > A wholly different expression for momentum is used for photons. yes and there is the famous formula for a **mixture* of photons and bigger particles !! ------------ > > > it is another indication about the need to know > > were and how to use it !!! > > 9bacause of ambiguity situations !!! > > -------------- > > > > Third, this rule ONLY applies for moving masses, and should not be > > > used for just anything that has momentum. Other entities also carry > > > momentum but not described by that rule. > > > > In the end, what momentum is, is whatever quantity can be ascribed to > > > a physical entity such that the total of that quantity for all objects > > > of all kinds in a closed system is constant. It's still remarkable > > > that such a rule can be found at all. > > > --------------------- > > > (:-) > > Hi abstract philosopher !! > > Nothing abstract about it. It's really very straightforward and > practical. > ----------------- now since you PD still was not able to bring ACTUAL SPECIFIC EXAMPLES i will do it instead of you : lets take a mass (not a photon) say an electron or even a proton (say like in the LHC) and examine it in TWO SITUATIONS: 1 it moves in a velocity muchless than c amd let it collide say with a lead screen and examine its momentum of collission wihtthat screen 2 lets take exactly the above particle but this time with a velocity *very close to c and examine its momentum collision with that above lead screen can you show us your analysis and calculations **comparing the two cases ??** incuding the *force* exserted on that screen !! that analysis can be of course not numerically but just by formulas btw the question is not only to PD it is for anyone else who want to do it (not including Feuerbacher from heidelberg .. because of obvious reasons (:-) TIA Y.Porat ---------------------------- |