Science fiction has come up with some cool things before, but out of all of them, time travel is up there as one of the coolest concepts to be thought of. Unfortunately, the nature of reality, along with the laws of physics doesn't allow us the opportunity of jumping into a wormhole and blasting into the future or past. But the same can't be said for photons. A paper has been written by a scientist from the University of Cambridge named Luke Butcher, where he describes a potential structure of a wormhole that could be remained open for long enough to let a photon to travel through it. This paper is submitted to Physical Review D journal and is published on the following site in an open access format: http://arxiv.org/pdf/1405.1283v1.pdf
The first suggestion of wormholes (http://www.space.com/20881-wormholes.html) came from the great Albert Einstein himself in 1935 alongside Nathan Rosen. Essentially, a wormhole is a hypothetical passageway that is similar to a whirlpool and would allow a daring trekker to break out of the limitations in the space-time continuum. A wormhole could potentially be an entrance to a parallel universe or it could bend through the fabric of the universe as we know it and end up at a different point of the cosmos in another time and area. However, the stability of wormholes are regarded as high risk and probably would not stay open for enough time to be used with the intention of time traveling.
Physicists then started to speculate whether something could be used to support the wormhole in order to keep it open. In 1988, it was suggested by a team of scientists from Caltech that negative energy could possibly be the solution. Because positive energy essentially attracts matter to the point of keeping the wormhole shut, then hypothetically, negative energy could potentially manifest the opposite effect and resist matter, subsequently holding the wormhole open.
At the time, those researchers began to look into the idea of the Casimir effect as the primary source for pumping negative energy into the wormhole to stabilize it. Plates that are parallel to each other in a space-like vacuum undergo certain quantum effects that end up trapping energy (depending on the circumstance, it could be either negative or positive energy) between them. Once a vortex created for a wormhole got started and negative energy got blasted into the center, it would provide the support needed for the hole to be open and hold back the collapse.
However, our problems don't end there. The wormhole would be way too small. When we look at science fiction, we see wormholes as massive openings that let people in giant spaceships pass through unscathed and with ease. In reality, a wormhole, if it even existed, simply wouldn't be wide enough for humans to get through the passageway. Butcher hypothesizes that while people can't travel through these tiny wormholes, it might be possible for photons to (http://phys.org/news/2014-05-physicist-wormholes-photon.html).
After running some calculations built off of prior research, Butcher's new model should be ready to the point of holding a wormhole open, but the problem is it would have to be extremely long and extremely narrow. Another problem is the dilemma of getting the negative energy into its accurate location, as the density of the Casimir energy would be zero when it gets renormalized. Buther writes his paper, "Nonetheless, the negative Casimir energy does allow the wormhole to collapse extremely slowly, its lifetime growing without bound as the throat-length is increased. We ﬁnd that the throat closes slowly enough that its central region can be safely traversed by a pulse of light.”
Even if these calculations are completely correct and Butcher was able to keep a wormhole open and let a photon travel through, that doesn't mean we'll be able to travel into the future and drink space beer just yet. This paper is only talking about holding the tunnel open and doesn't get into the intricacies of what would happen if a person stepped into it - or even a photon for that matter. For now, we're just going to have to sit there and imagine what we'd do once we have that power.