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Re: Speed of light (was: Science School)

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kenseto wrote:

> On Tuesday, April 11, 2017 at 12:21:20 PM UTC-4, Thomas 'PointedEars' Lahn
> wrote:
>> kenseto wrote:
>> > Your argument supports the concept that light is being transmitted by a
>> > medium occupying space.
>> No, it does not.  How did you get that idea?
> 
> You said that light takes 8 minute from the sun to arrive at the
> earth.....

About 8 minutes [∆t = (1 AU)∕c₀], yes.

> that means that light is being transmitted by a medium

No.  See also <https://en.wikipedia.org/wiki/Light> (*all* of it).

> and the speed of light in that medium is 300,000 km/sec.

The speed of light in vacuum is c₀ = 299'792'458 m∕s.  You can either say 
that the vacuum is the medium through which (_not_: by which) light is 
transmitted, or as vacuum is defined as “space void of matter” (QFTs 
notwithstanding), that there is no medium.  It is usually generally stated 
that the transmission of light, and electromagnetic radiation in general, 
does not require a medium.

In the case of the Sun it makes sense to consider the interplanetary medium, 
because that is not a perfect vacuum, and so the speed of light in that 
medium is less than c₀.  But that is not a medium that allows, but one that 
*hinders* (slightly, given the miniscule number of particles and their 
kinetic energies) the transmission of light.

> With that speed it takes 8 minute for light from the sun to arrive at the
> earth.

The travel time would be about the same in a perfect vacuum, i.e. with no 
other (real) particles in-between.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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Science School The Starmaker <starmaker@ix.netcom.com> - 2017-04-09 13:03 -0700
  Re: Science School The Starmaker <starmaker@ix.netcom.com> - 2017-04-09 13:33 -0700
  Re: Science School Robert Bannister <robban@clubtelco.com> - 2017-04-11 10:10 +0800
    Re: Science School Paul Colquhoun <newsposter@andor.dropbear.id.au> - 2017-04-11 17:39 +1000
    Re: Science School Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-11 15:06 +0200
      Re: Science School Jolie Osokuro <uuol@oowo.ou> - 2017-04-11 13:32 +0000
        Re: Science School Poutnik <poutnik4nntp@gmail.com> - 2017-04-11 15:48 +0200
      Re: Science School kenseto <setoken@att.net> - 2017-04-11 08:25 -0700
        Re: Science School Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2017-04-11 18:16 +0200
          Re: Science School Wendi Maddox <ox@awdodww.oe> - 2017-04-14 14:40 +0000
        Speed of light (was: Science School) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-11 18:21 +0200
          Re: Speed of light (was: Science School) kenseto <setoken@att.net> - 2017-04-11 11:25 -0700
            Re: Speed of light (was: Science School) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-11 20:49 +0200
              Re: Speed of light (was: Science School) mlwozniak@wp.pl - 2017-04-11 12:17 -0700
                Re: Speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-11 22:00 +0200
              Re: Speed of light (was: Science School) kenseto <setoken@att.net> - 2017-04-12 06:34 -0700
                Re: Speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-13 00:36 +0200
                Re: Speed of light mlwozniak@wp.pl - 2017-04-13 05:29 -0700
                Re: Speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-13 14:41 +0200
                Re: Speed of light mlwozniak@wp.pl - 2017-04-13 06:07 -0700
                Re: Speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-13 15:20 +0200
                Re: Speed of light mlwozniak@wp.pl - 2017-04-13 06:25 -0700
                Re: Speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-13 15:43 +0200
                Re: Speed of light mlwozniak@wp.pl - 2017-04-13 06:53 -0700
                Re: Speed of light kenseto <setoken@att.net> - 2017-04-13 05:47 -0700
                Re: Speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-13 15:15 +0200
                Re: Speed of light moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-13 16:54 +0000
                Re: Speed of light kenseto <setoken@att.net> - 2017-04-13 10:44 -0700
                Re: Speed of light moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-13 21:33 +0000
            Re: Speed of light (was: Science School) moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-11 20:22 +0000
              Re: Speed of light (was: Science School) kenseto <setoken@att.net> - 2017-04-12 07:16 -0700
                Re: Speed of light (was: Science School) moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-12 15:49 +0000
                Re: Speed of light (was: Science School) mlwozniak@wp.pl - 2017-04-12 10:04 -0700
                Re: Speed of light (was: Science School) kenseto <setoken@att.net> - 2017-04-13 05:22 -0700
                Re: Speed of light (was: Science School) moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-13 16:33 +0000
  Re: Science School Nobody <nobody@nowhere.nohow> - 2017-04-11 00:41 -0400

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