Would a Photon at rest have potential energy?or potential momentum?
830869
A Photon being a particle of light would never be at rest.  It is energy in motion.
9267
photons don't have mass, they're packets of energy.
797659
Yes. A quantum of energy is invariant unless it interacts with another particle. A certain photon of a given frequency and wavelength has invariant energy.
1017395
A photon is a quantum of the vibrational energy of the space grid (as in the image above). At any one point on the wave, photons are produced out of the zero-point and then oppositely, photon holes are produced. Hence, it must be the case that these oscillations up and down come in discrete steps--or quanta.\n\n \n\nWhen a particle from the quantum vacuum acquires energy from a charged particle of matter, it may expand from the addition of this excitation energy to become an ordinary photon. Energy, therefore, expands the size of a virtual photon in ground state.\n\n \n\nA virtual photon, thus, is a "collapsed" short-range quantum that becomes an ordinary photon when given energy from an excited charged particle. Hence, the primary reason that we do not observe the photons that exist in the quantum vacuum, is because the quanta of space-time that compose the vacuum have a very minute amount of energy within them and are, therefore, too small to be observed directly. However, such vacuum quanta may become observable and measurable as ordinary photons after emission.\n\n \n\nWhen actualization takes place, we may measure photons and photonic energy hitting a measuring device.  But, while in-flight, we may not speak about photons at all, because technically speaking they are not photons.  So, when Planck's equation says that energy comes in lumps E = hf, this only refers to a state of an EM wave after an actualization or measurement has happened.  Prior to this we have only Kant's noumenal "wave" condition.  \n\nphotons must have higher frequencies, by exactly one hertz, than the expected difference of the energy levels of the electrons from which they received energy. Additionally, photon wavelengths must include a very long 3 x 10^8 meters to be added to all emitted wave fronts
1120914
I believe it would be instantaneous, but it's a fascinating question.  Perhaps the speed of light, because there are those who argue that gravity is another form of energy generally, and the whole "unified field" thing that I confess I do not understand at all.  \n\nI suppose part of the question is how the sun could "suddenly vanish" in the first place.  Would it in fact vanish instantaneously, or at the speed of light?  Even if it fell into a black hole, that would be an event, and events have a place in space/time.  That we would not know it had vanished until the light stopped coming to us some minute or two later (speed of light for 93 million miles), because of the light, then would gravity be following with that light?  The light is, after all, energy and therefore -- says Einstein -- matter, and that's what responds to gravity . . . \n\nGeeze, you make my head hurt with these puzzles.  I hope some really heavy-duty physicist takes a shot at this question!
952119
The photon has zero mass (it does, however, have rest mass - as in M=E/C^2). \n\nLike all quanta, the photon exhibits wave and particle properties. \n\nIt is important to remember that mass and energy are equivalent. A photon is only referred to as a particle because of certain properties that light exhibits - the "particle" is actually no more than a quanta of pure light energy - and, as such, is indeed dimensionless in the conventional sense of density and volume.
492443
It is theoretically possible, but highly impractical.  Think about the equation E=mc^2.  C is the speed of light - 186000 meters per second.  So from that equation, you can see that a tiny bit of mass is the equivalent of a huge amount of energy.  Conversely, it would take a huge amount of energy to make even a tiny amount of mass.
188402
You don't need a force to enable something to travel, it's quite the opposite! Remember the Newton's First Law: an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.\nOf course Newton's Laws doesn't directly apply to light, which is best described by quantum mechanics as a flow of photons. However, I'm referring to it because its rationale holds also for photons and its formulation is very intuitive (opposite to quantum mechanics).\nOnce photons are emitted by a light source (for instance, electrons changing energetic level within an atom), they "just go", with no need of energy other than the energy that produced them in the first place.
1089315
I'd say option B. Each photon contains one fragment of the image. But actually, there are no such things as photon particles. The "waves" that "photon particles" create are actually part of the photon themselves.
159391
We say that a photon is massless because it is in the usualy meaning of the word.  A photon has zero rest mass.  However, since it obviously has energy, it has a momentum.\n\nRead through this site and some of the related articles, I think it explains it very well,\nhttp://math.ucr.edu/home/baez/physics/ParticleAndNuclear/photon_mass.html
346637
Photon has mass so far it has energy but it depend on the nature of particle of ligth. You can apply this formula to get the mass of the photon; m = hf/c^2. (Where h=Planck's constant, f= frequency, c= speed of ligth)
643435
I could not understand what did you mean by 'as such'! But, gamma rays are also photons and if certain conditions (conservation theorems, energy requirements) are satisfied, they could undergo the process of pair-production whereby they could be converted into electron-positron pairs (an experimentally observed fact).\n \nPair-production occurs when a 1.022 MeV gamma-photon interacts with a heavy atomic nucleus, and produces an electron and a positron without violating conservation of momentum. Pair production cannot occur in empty space out of a single photon because the momentum of the initial photon must be absorbed by something, and the heavy nucleus is thus required to conserve both momentum and energy. The energy of the photon 1.022 MeV, as described above, is the total energy of twice the electron mass (according to E = mc^2). Indeed energy is being converted into mass in this process!
59698
It is not possible to experimentally measure something to have a value of exactly zero. The current limit on the mass of the photon is < 10^25 times lighter than the proton.\n\nThe idea of a particle's mass changing with velocity has not been used by serious physicists for several decades. We now rewrite the momentum equation as\nmomentum = gamma*mass*velocity , where the factor gamma describes the effect previously known as "relativistic mass".\n\nThe energy of a particle is \nenergy = gamma * mass * c^2 (try setting gamma=1 for a stationary particle) \nso we can write momentum = energy * velocity / c^2\nor momentum = energy/c  for particles moving at the speed of light.\nSo, even though a photon has zero (or very small) mass, it still has momentum, which it can transfer to an electron.
36596
That's a big "if", that's some car!\n\nOK, I'll go there:\n\nThe photons in the forward direction could not escape thre filaments so they'd build up there, but the filaments would not blow because they'd be infinite mass.  Boring answer, really.  Nothing would happen.
595852
It would end up as heat. At least that is the usual place you say all the energy went when you can't otherwise account for it. Like where does the energy go when you drop a bean bag on the ground? Yell out loud? Turn on a light? slow your fall with a parachute? And on and on and on.
895733
Energy=Mass * (speed of light)^2
92282
The photon has energy. And energy can be converted into mass. Remember \n\nE^2=(m^2)( c^4) + (p^2) (c^2)\n\n----------\n\nI would agree with cedykeman1 that it does seem somewhat controversial to suggest that the photon is unstable. However, its energy can still probably be converted to matter, although the chance of getting those 3 exact particles seems a bit far-fetched (probably their antiparticles have to be produced as well, and various conservation laws followed carefully).\n\n--------\nI do not know what to say about goring, except to smile.