Do quantum of light ever get tired?

  1. socratus profile image60
    socratusposted 5 years ago

    Do quantum of light ever get tired?

    Do neutrinos ever get tired?
    Do quantum of light ever get tired?
    To answer to this question we must know:
    what quantum of light is.
    But  Einstein wrote sadly :
    ‘ All these fifty years of conscious brooding have brought me
    no nearer to the answer to the question, 'What are light quanta?'
    Nowadays every Tom, Dick and Harry thinks he knows it,
    but he is mistaken. ‘

  2. Larry Fields profile image78
    Larry Fieldsposted 5 years ago

    Endless  rumination about the 'true nature' of a quantum of light is a waste of time. As a visually-oriented person, I'm prone to that. To quote a famous piece of doggerel,

    "The man behind the microscope,
    Has this advice for you:
    Don't ask what it is;
    Just ask what does it do?"

    That said, I'll interpret "tired" to mean red-shifted, for the sake of internal consistency. Although I'm not a physicist, I know of three mechanisms by which a photon can become red-shifted.

    1. Ordinary Doppler redshift
    2. Special Relativity redshift. An observer/passenger on a high-speed train points a portable laser out the window. His measurement of the laser light's wavelength will be slightly less than that of a stationary observer standing to the side of the railroad tracks. Of course, I'm assuming arbitrarily accurate measurements on the part of both observers.
    3. General Relativity redshift, aka gravitational redshift. A photon escaping the gravity well of a massive star will be red-shifted slightly.  More precisely, the spectral 'lines' of that star would appear to red-shifted, relative to those of a smaller star.