Can Photons Push objects (Things with mass)?

Answer 1

I just want to clarify a few things here. The PhD guy is correct, momentum can be transferred from photons to objects with mass.

Solar wind is not photons. Solar wind is charged particles from the sun and has nothing to do with photons. The 'northern lights' has nothing to do with photons, light is simply emitted when the charged particles from the solar wind interacts with the higher atmosphere.

Momentum, in quantum mechanics, is given by the operator:

P = -i hbar nabla

where nabla is the grad operator, hbar is the reduced planck constant and i is the complex number sqrt(-1). The energy of the photon is given by:

E = hbar omega

where omega is the angular frequency of the light. From this, the wavenumber k can be calculated and the momentum p can be worked out from:

p = hbar k

(Note that, here, p and k are vectors).

So the magnitude (or absolute value) of the momentum of a single photon is:

p = h f / c

where h is plancks constant, f is the frequency of light and c is the speed of light. From this you can work out how much momentum can be transferred by the impact of a single photon and, consequently, how much can be transferred by a flux of photons. Importantly, if the photons are reflected, twice as much momentum is exchanged!

Answer 2

Yes of course. I agree totally with the previous answer and disagree with the guy that said that photons cannot push objects. Our solar system was formed like this and this is why the lighter gas planets were formed far away( lighter so pushed easier and further by the radiation of the Sun) The heavy planets(solids) were formed closer to the sun but still away because the photons could not push so easily heavy stuff

Answer 3

Well my PhD thesis was about photons colliding with protons at high energy. In this case the photon not only deflected the massive object (the proton) but caused it to break into jets of particles. Now that is cheating slightly as these photons are not entirely real, but the very short lived means by which electromagnetic energy/force was transmitted.

However as the quantum by which electromagnetic force is transmitted, yes photons can "push" massive objects.

There are cases where Physicists have used Laser beams to hold otherwise unstable particles together, or in one place for study. e.g.
http://web.mit.edu/newsoffice/2005/matter.html

Answer 4

Yes, they can and do.

It is photon pressure that holds the core of the sun up against collapse under its own gravity.

But it only happens when there are a lot of photons.

The solar wind can indeed push things too, but it is made of particles and not photons. And the famous Crooke's Radiometer which purports to show photons pushing blades inside a glass bulb is doing nothing of the kind - motion of the blades is complex, but is essentially caused by heating of residual gases.

Answer 5

Why yes they can. Photons carry energy which may be converted by a massive object into kinetic energy. Solar wind is a great example of photons pushing an object.

I would not listen to the moron who said no, he obviously doesn't read much physics literature.

Answer 6

The Northern and Soutern Lights are also an example of photons collide with magnetised particles in the Earth's atmosphere. As per Newtons Law, the collision would result in the kinetic energy from the photon to be transfered onto the atmospheric particle, therefore pushing the said particle in the direction of the force...

Answer 7

NO they cant. Photons, unlike electrons, are imaginary particles which act like a medium that transmit quantum energy. Thus, Mass of the photons is ZERO.

According to the equation, F=ma, when m(mass) = 0, Force exerted is also ZERO.

Thus Photons cant push any objects/particles but they can just transmit energy.

Answer 8

Yes, obviously they can. That's why you get solar wind, which can even push a spacecraft employing a solar sail.