The universe exists so you can photograph it!

A common school experiment which everyone will have seen is the interference fringes experiment. A light is shone through two slits and appears as series of light and dark fringes on paper or photographic film on the other side of the slits. This was first observed by Young around 1800, and we are taught that the pattern is due to the wave nature of light,caused by the waves interfering with each other and being reinforced at the bright fringes and cancelled out in-between.

But what happens when you turn the brightness of the light down continually until only a single photon passes through the slit at any one time? Say, one photon per second. Common sense would say that as there is only one photon at a time, there would not be any interference and you should get a random spread of light on the film. However, that is not what we observe, what we actually see is the same interference fringes. Spooky! So each photon that goes through the slit appears to be telling the other photons that come later, which one it went through and where it is.

Now another experiment is to use a photon detector to determine which slit the photon went through and its exact trajectory. When you do this, the interference patterns disappear and you can indeed detect the path of each photon. So now it appears that the photons are no longer talking to each other. Our change in experiment has changed the results.

This wave particle duality has puzzled physicists since it was first observed. Experimental techniques have improved and different methods have been found to test how well it holds and whether there are any violations. One of the most interesting experiments involves setting up the screen to detect the wave pattern in the normal way, but then placing a photon detector behind the screen. The results are startling. If there is no detector there is a pattern, if there is a detector, there is none.

So even more spookily the photon can talk to its own past and change its state.

To explain this you have to consider that the photon exists in a superposition of states throughout time, and it is the act of observing the photon that causes its state to become defined. Basically it is both a wave and a particle at the same time, and choosing to detect is as a particle forces it to be a particle throughout time.

Now there is train of thought which states that all particles are in this superposition of states until an observer causes the state to become fixed. Experiments in quantum mechanics have shown this to be true. If this is true then it is not unreasonable to assume that at the very moment of creation of the universe, all the particles, and the entire state of the universe existed as a superposition of all possible states, and that all that was lacking was an observer to force the universe into a single state.

The spooky thing about this is that one of those states of superposition would include a photographer looking through a lens at a particular scene, and if the nature of the universe allows the state in the future to influence the state of the past, then the simple fact of your ability to exist and observe the universe would cause the superposition of states to collapse and create a universe in which you will exist and take your photograph.

Maybe this is why the universe exists in a state that you can see, it’s simply because you can exist to see it. You are, in fact, the creator of all that you see.

It just so happened that last week the universe’s wave state collapse resulted in me photographing Rachel and I thought I’d take some glamour style shots. So here is one of them. Please Jimmy, don’t cringe too much.