Intensity Related to Blue and Red Shifts
in [Relativity]
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From: Yimin Rong on 23 Feb 2010 17:04 Consider an observer moving at an extremely high velocity relative to the CMBR (e.g. v = 0.999999c). In the direction of travel, one would expect the CMBR to be blue shifted into infrared and visible. Would there be a difference in the intensity of the radiation in the blue shifted direction vs. the red shifted direction vs. at rest? Let's say on his measuring apparatus he's getting 1 nW/m^2 at rest, keeping everything else the same, at v is he getting <<, <, >, or >> 1 nW/m^2? I found this: http://en.wikipedia.org/wiki/File:Firas_spectrum.jpg. The intensity is given in ergs / (centimeter squared x steradian x second x inverse centimeter). Can that be converted to something like W/m^2? Thanks for reading, Yimin Rong
From: BURT on 23 Feb 2010 17:19 On Feb 23, 2:04 pm, Yimin Rong <yiminr...(a)yahoo.ca> wrote: > Consider an observer moving at an extremely high velocity relative to > the CMBR (e.g. v = 0.999999c). > > In the direction of travel, one would expect the CMBR to be blue > shifted into infrared and visible. Would there be a difference in the > intensity of the radiation in the blue shifted direction vs. the red > shifted direction vs. at rest? > > Let's say on his measuring apparatus he's getting 1 nW/m^2 at rest, > keeping everything else the same, at v is he getting <<, <, >, or >> 1 > nW/m^2? > > I found this:http://en.wikipedia.org/wiki/File:Firas_spectrum.jpg. > The intensity is given in ergs / (centimeter squared x steradian x > second x inverse centimeter). Can that be converted to something like > W/m^2? > > Thanks for reading, > > Yimin Rong There is blueshift going into gravity and an equal redshift comming out. Light's fundamental energy is conserved under gravity. Mitch Raemsch
From: dlzc on 23 Feb 2010 18:10 Dear Yimin Rong: On Feb 23, 3:04 pm, Yimin Rong <yiminr...(a)yahoo.ca> wrote: > Consider an observer moving at an extremely high > velocity relative to the CMBR (e.g. v = 0.999999c). > > In the direction of travel, one would expect the > CMBR to be blue shifted into infrared and visible. > Would there be a difference in the intensity of > the radiation in the blue shifted direction vs. > the red shifted direction vs. at rest? No real difference, it would be increased / decreased by the same "factor" as the blue / red shift. > The intensity is given in ergs / (centimeter > squared x steradian x second x inverse > centimeter). Can that be converted to something > like W/m^2? Sure can, if you infer a geometry. http://en.wikipedia.org/wiki/Intensity_(physics) David A. Smith
From: BURT on 23 Feb 2010 20:16 On Feb 23, 3:10 pm, dlzc <dl...(a)cox.net> wrote: > Dear Yimin Rong: > > On Feb 23, 3:04 pm, Yimin Rong <yiminr...(a)yahoo.ca> wrote: > > > Consider an observer moving at an extremely high > > velocity relative to the CMBR (e.g. v = 0.999999c). > > > In the direction of travel, one would expect the > > CMBR to be blue shifted into infrared and visible. > > Would there be a difference in the intensity of > > the radiation in the blue shifted direction vs. > > the red shifted direction vs. at rest? > > No real difference, it would be increased / decreased by the same > "factor" as the blue / red shift. > > > The intensity is given in ergs / (centimeter > > squared x steradian x second x inverse > > centimeter). Can that be converted to something > > like W/m^2? > > Sure can, if you infer a geometry.http://en.wikipedia.org/wiki/Intensity_(physics) > > David A. Smith The geometry is round. Mitch Raemsch
From: BURT on 23 Feb 2010 20:17
On Feb 23, 5:16 pm, BURT <macromi...(a)yahoo.com> wrote: > On Feb 23, 3:10 pm, dlzc <dl...(a)cox.net> wrote: > > > > > > > Dear Yimin Rong: > > > On Feb 23, 3:04 pm, Yimin Rong <yiminr...(a)yahoo.ca> wrote: > > > > Consider an observer moving at an extremely high > > > velocity relative to the CMBR (e.g. v = 0.999999c). > > > > In the direction of travel, one would expect the > > > CMBR to be blue shifted into infrared and visible. > > > Would there be a difference in the intensity of > > > the radiation in the blue shifted direction vs. > > > the red shifted direction vs. at rest? > > > No real difference, it would be increased / decreased by the same > > "factor" as the blue / red shift. > > > > The intensity is given in ergs / (centimeter > > > squared x steradian x second x inverse > > > centimeter). Can that be converted to something > > > like W/m^2? > > > Sure can, if you infer a geometry.http://en.wikipedia.org/wiki/Intensity_(physics) > > > David A. Smith > > The geometry is round. > > Mitch Raemsch- Hide quoted text - > > - Show quoted text - You can get behind light. |