CMBR's motion wrt the Earth
in [Relativity]
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From: mluttgens on 6 Sep 2009 08:53 CMBR's motion wrt the Earth ------------------------------------------ In cosmology, cosmic microwave background (CMB) radiation (also CMBR, CBR, MBR, and relic radiation) is a form of electromagnetic radiation filling the universe. (from http://en.wikipedia.org/wiki/CMBR) By measuring the amount of the dipole anisotropy (the bluest part of the sky is .0033 K hotter than average), we can determine the magnitude of the earth's motion with respect to the CMB: the earth is moving at a speed of 370 km/s in the direction of the constellation Virgo. (from http://www.phy.duke.edu/~kolena/cmb.htm) It (the CMBR) does move with respect to an object. (from PD <thedraperfam...(a)gmail.com>, Sep 5, 2009) Clearly, the Earth moves wrt the CMBR. According to SR, reciprocally, the CMBR moves wrt the Earth. Can somebody explain how, physically, an electromagnetic radiation filling the universe can move relative to the Earth? Marcel Luttgens
From: Inertial on 6 Sep 2009 09:46 "mluttgens" <mluttgens(a)orange.fr> wrote in message news:13e7a567-eef2-4826-b6ce-007654c4b7e0(a)t2g2000yqn.googlegroups.com... > > CMBR's motion wrt the Earth > ------------------------------------------ > > In cosmology, cosmic microwave background (CMB) radiation > (also CMBR, CBR, MBR, and relic radiation) is a form of > electromagnetic radiation filling the universe. > (from http://en.wikipedia.org/wiki/CMBR) Yeup > By measuring the amount of the dipole anisotropy (the bluest > part of the sky is .0033 K hotter than average), we can determine > the magnitude of the earth's motion with respect to the CMB: And the motion of the CMB wrt the earth .. which is the same only opposite > the earth is moving at a speed of 370 km/s in the direction > of the constellation Virgo. > (from http://www.phy.duke.edu/~kolena/cmb.htm) Though that obviously varies during the year as the earth accelerates around the sun, and as the sun and earth move around the galactic core. > It (the CMBR) does move with respect to an object. > (from PD <thedraperfam...(a)gmail.com>, Sep 5, 2009) If a moves relative to B then B is moving relative to A. > Clearly, the Earth moves wrt the CMBR. Yes > According to SR, And to classical Newtonian and Galilean physics > reciprocally, the CMBR moves wrt the Earth. > > Can somebody explain how, physically, an electromagnetic > radiation filling the universe can move relative to the Earth? The same way that the earth can move relative to the CMBR frame. Its the same motion from two different points of view. How can the CMBR frame (or any frame) be at rest relative to us when we are moving in it?
From: N:dlzc D:aol T:com (dlzc) on 6 Sep 2009 11:23 Dear mluttgens: "mluttgens" <mluttgens(a)orange.fr> wrote in message news:13e7a567-eef2-4826-b6ce-007654c4b7e0(a)t2g2000yqn.googlegroups.com... .... > Clearly, the Earth moves wrt the CMBR. According to SR, > reciprocally, the CMBR moves wrt the Earth. > Can somebody explain how, physically, an electromagnetic > radiation filling the universe can move relative to the Earth? The CMBR moves at c. So I think you mean "how can the medium that quenched, producing the CMBR radiation we still receive, appear to be moving wrt the Earth?" Does it hurt to be you? David A. Smith
From: Dono. on 6 Sep 2009 12:45 On Sep 6, 5:53 am, mluttgens <mluttg...(a)orange.fr> wrote: > > Can somebody explain how, physically, an electromagnetic > radiation filling the universe can move relative to the Earth? > It wouldn't do any good.
From: eric gisse on 6 Sep 2009 17:39
mluttgens wrote: [...] > Can somebody explain how, physically, an electromagnetic > radiation filling the universe can move relative to the Earth? Seriously? > > Marcel Luttgens |