The autumn leaves are falling like rain. Although my neighbors are all barbarians and you, you are a thousand miles away, there are always two cups at my table.

T’ang Dynasty poem

Ten thousand flowers in spring, the moon in autumn, a cool breeze in summer, snow in winter. If your mind isn't clouded by unnecessary things, this is the best season of your life.

~ Wu-men ~


Tuesday, August 07, 2007

Who needs fiction: Time Travel


Below is an excerpt from an article that appeared in EETimes, a trade magazine for engineers. If you click on the link, you'll be directed to the full article.

Israeli researchers tout time machine model

NETANYA, Israel — Researchers at the Technion University (Haifa, Israel) claim they have developed a theoretical model of a time machine that, in the distant future, could enable future generations to travel into the past.

The team's findings were published in the latest issue of Physical Review.

"In order to travel back in time, the spacetime structure must be engineered appropriately," explains Professor Amos Ori of the Technion's Faculty of Physics. "This is what Einstein's theory of general relativity deals with. It says that spacetime can be flat. That is " it has a trivial, simple structure. But it can also be curved with various configurations."

The team stresses the main question is whether — according to the principles of curvature development in the theory of relativity — a time machine can be created. "In other words " can we cause spacetime to curve in such a way as to enable travel back in time? Such a journey requires a significant curvature of spacetime, in a very special form."

The researchers explain that traveling back in time is actually closing time-like curves so we can go back to an event at which we were present in the past. In flat space, it is not possible to close curves and go back in time. In order for closed time-like curves to exist, there has to be a curvature of a specific form on spacetime.

The question Prof. Ori is investigating is whether the laws of gravity permit the development of spacetime with the required curvature (closed time-like curves).

In the past, scientists raised a number of objections to this possibility. Now, Prof. Ori is proposing a theoretical model for spacetime that could develop into a time machine.

No comments: