# Can Light be Cut?And if so then what would it take.

1. May 10, 2012

### promeus

As far as I know it Light is composed of Photons.So what I am asking here is if those particles could be cut or split rather apart? What would it take to accomplish such a feat?

Bonus Question:Can an electric current be cut?

2. May 10, 2012

### A.T.

A lightsaber?

3. May 10, 2012

### davenn

so you are asking if you can split a photon in half ?
I am not aware of that being able to be done

yes ---- turn the supply off

Dave

4. May 10, 2012

Read the wikipedia article on elementary particles.

5. May 11, 2012

### Thecla

Good question Promeus. Excited atomic states take about 10 nanoseconds to emit a photon. So traveling at a speed of 10^8 meters/second, a typical visible photon would be about one meter long. What would happen if a shutter on a pin hole closed on a single photon while it was half-way through the pin hole?

6. May 11, 2012

### Bobbywhy

I disagree with your reasoning. The time it may take for an atom to emit a photon cannot be used to measure the "size" of that photon. The photon does not start at nanosecond #1 and be continuously "emitted" during that entire 10 nanosecond duration. That 10 nanoseconds is the delay time before its emission.

As far as I know, the photon cannot be said to have a physical size.

7. May 11, 2012

### Infinitum

Photons are quantized, meaning you cannot get them in fractions, but only in positive integral multiples of $h\nu$