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Traden4Alpha
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Dark Matter Is Crap

July 11th, 2012, 11:39 am

QuoteOriginally posted by: outrunQuoteOriginally posted by: Traden4AlphaQuoteOriginally posted by: outrunQuoteOriginally posted by: rmaxQuoteOriginally posted by: outrunit's always red but de Brolgie matter waves are different from photon wavesIndeed and colour is from photons reacting with your retina. If electrons reacted with the retina you have have something analogous to a CRT.Indeed! And the retina is the reason that there is "pink", which isn't part of the spectrum.Moreover, one might argue that individual photons don't have colour because the cone cells of the retina are inefficient detectors and the cells have no direct ability to estimate the energy of specific photons. Instead, the eye measures aggregate flux using several types of sensors which have broad wavelength-dependent responses to light. (The rod cells of the retina are extremely sensitive and can detect single photons but they don't sense colour.)P.S. The eye is a little bit like a CRT in that cosmic rays can be directly sensed as flashes of light.Besides the cosmic flashes, I also enjoy the "blue field entoptic phenomena": you can see individual white blood cells run through your tiny blood vessels in front of your retina if you stare at the blue sky. No need for a telescope / microscope!Indeed!If you want to see even more of the inside of the eye, make a modest-sized pinhole (1-2mm) in a piece of cardboard, hold it in front of your eye, and stare at a brightly lit blank wall or the sky whilst rapidly oscillating the pinhole. You can perceive the shadows of the retina's vascular system and other retinal features with this method. This technique works because the retina is more sensitive to changes in light level than it is sensitive to average light level (the eye is NOT a camera!).
 
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quantmeh
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Dark Matter Is Crap

July 11th, 2012, 1:08 pm

QuoteOriginally posted by: Traden4AlphaIf you want to see even more of the inside of the eye, make a modest-sized pinhole (1-2mm) in a piece of cardboard, hold it in front of your eye, and stare at a brightly lit blank wall or the sky whilst rapidly oscillating the pinhole. You can perceive the shadows of the retina's vascular system and other retinal features with this method.you can also experience a seizure, but it's worth the discovery
 
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Traden4Alpha
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Dark Matter Is Crap

July 11th, 2012, 1:29 pm

QuoteOriginally posted by: quantmehQuoteOriginally posted by: Traden4AlphaIf you want to see even more of the inside of the eye, make a modest-sized pinhole (1-2mm) in a piece of cardboard, hold it in front of your eye, and stare at a brightly lit blank wall or the sky whilst rapidly oscillating the pinhole. You can perceive the shadows of the retina's vascular system and other retinal features with this method.you can also experience a seizure, but it's worth the discoverySeizures are a synthetic product of the psycho-pharma-industrial complex. I believe in elliptical fits not epileptic fits.
 
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Fermion
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July 12th, 2012, 1:34 am

QuoteOriginally posted by: rmaxQuoteOriginally posted by: outrunit's always red but de Brolgie matter waves are different from photon wavesIndeed and colour is from photons reacting with your retina. If electrons reacted with the retina you have have something analogous to a CRT.This distinction between electron color and photon color is off-track. Do we say that the sky has no color? No, we say it is blue during the day, because that is the predominate color of light coming from the sky when the sun is high and we talk about the red sky in the morning or evening.Likewise, the color of an electron is given by the frequencies of the photons it emits or resonates with. Sodium electrons, for instance, are predominately yellow when excited -- which is why burning sodium shows a yellow light.
 
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Traden4Alpha
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Dark Matter Is Crap

July 12th, 2012, 11:04 am

QuoteOriginally posted by: outrunQuoteOriginally posted by: FermionQuoteOriginally posted by: rmaxQuoteOriginally posted by: outrunit's always red but de Brolgie matter waves are different from photon wavesIndeed and colour is from photons reacting with your retina. If electrons reacted with the retina you have have something analogous to a CRT.This distinction between electron color and photon color is off-track. Do we say that the sky has no color? No, we say it is blue during the day, because that is the predominate color of light coming from the sky when the sun is high and we talk about the red sky in the morning or evening.Likewise, the color of an electron is given by the frequencies of the photons it emits or resonates with. Sodium electrons, for instance, are predominately yellow when excited -- which is why burning sodium shows a yellow light.Hmm.. this is very fuzzy. Electrons don't have a color without context. You mention "Sodium electrons" but that's not a type of electron, those electrons are indistinguishable from Silicon electrons which gives a very different emission pattern when excited. The photon absorption / emission of atoms is also a completely different things from matter waves of electron itself. The Rayleigh scattering of blue light in the sky is *yet* again something different. It's an atmospheric filter function of the photons emitted from the sun (and the reaction between the photon and the retina).Color originates in the retina where a signal gets fired to the brain due to some stimulus. Some stimuli -like firing an electron beam in someones eye- probably won't give a color sensation.Indeed! The emission lines of sodium are as much a function of the sodium atom's protons as they are a function of its electrons. Moreover, once a sodium electron has emitted it's yellow photon, the electron is no longer yellow.The retina transduces wavelength-related information on populations of photons over a region of the retina (the eye cannot detect the colour of a single photon). The brain interprets and assigns the detected patch of colour to a corresponding object in the visual field (note that there's all sorts of artifacts and approximations in this system -- in essence, the brain paints sloppy patches of color onto a black-and-white line drawing of the scene). Whether a given type of object has color then depends on it consistently and persistently reflecting or emitting populations of photons of a limited range of wavelengths. Electrons, in general, don't do this.Of course, we can extend the notion of colour to single photons (which is something the eye can't do) and we can further extend the notion of colour to be a range of wavelengths or energies.
 
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quantmeh
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July 12th, 2012, 12:21 pm

QuoteOriginally posted by: Traden4AlphaSeizures are a synthetic product of the psycho-pharma-industrial complex. i've witnessed them many times, they're real
 
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Traden4Alpha
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Dark Matter Is Crap

July 12th, 2012, 12:30 pm

QuoteOriginally posted by: quantmehQuoteOriginally posted by: Traden4AlphaSeizures are a synthetic product of the psycho-pharma-industrial complex. i've witnessed them many times, they're realNo you haven't. It's just an example of mass hysteria.Can you prove you've witnessed them with a repeatable experiment?
 
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quantmeh
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July 12th, 2012, 1:17 pm

QuoteOriginally posted by: Traden4AlphaCan you prove you've witnessed them with a repeatable experiment? i had a classmate who repeated it multiple times. i wouldn't say that it was hysterical.
 
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rmax
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November 1st, 2013, 8:07 am

Oh Joy! We have found NOTHING!
 
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Traden4Alpha
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Dark Matter Is Crap

November 1st, 2013, 10:55 am

QuoteOriginally posted by: rmaxOh Joy! We have found NOTHING!Dark matter must be very dark indeed!
 
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ExSan
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Dark Matter Is Crap

November 1st, 2013, 10:58 am

QuoteOriginally posted by: Traden4AlphaQuoteOriginally posted by: rmaxOh Joy! We have found NOTHING!Dark matter must be very dark indeed!it implies it exists isn't it ?. But if it exist how come no one can prove it ???
 
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Traden4Alpha
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May 15th, 2014, 8:07 pm

To a first approximation, ordinary Hubble constant expansion doesn't seem large enough. The sun, for example, has an orbital velocity of about 220 km/sec. The Hubble constant expansion effect WRT the center of the Milky Way galaxy is only 0.6 km/sec. And the combined tangential velocity (what a distant astronomy would measure as the orbital velocity) would be 220.001 km/sec. Of course, if the density of matter modulates the Hubble constant, then it might be quite different.
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