Tuesday, 22 January 2013

Can Time Literally Stop?

According to Professor Jose Senovilla, Marc Mars and Raul Vera of the University of Basque Country, yes. This was the radical solution that the group of scientists have come up with to solve one of the biggest mysteries of the Universe, the dark energy. Dark energy is the name scientists gave to the unknown energy that is fundamentally changing our Universe.

As physics developed in the 20th century, scientists have assumed three possibilities as the ultimate fate of the universe, they were dependent on the shape and the density of the Universe. If Omega (the ratio of actual density of the Universe to the critical density) is less than 1, then the Universe is sphere-like and will expand at an ever-slowing rate before it completely comes to a halt and starts collapsing on itself, presumably creating another Big Bang in the future and starting the whole cycle again. If Omega is less than 1, then Universe is negatively curved (see image below) and expands at an ever expanding rate. There is also another option, in my opinion, the most interesting one. If Omega equals exactly to one, then  the Universe is flat (yes, you read that correctly) and expands at an ever-slowing rate, but never completely coming to a halt, similarly to our favorite high school function, asymptote. Interestingly enough, that seems to be the case! The Universe is flat up to 1% to 2% and has Omega of exactly 1. Which all seemed cool and perfect, until scientists realized that the Universe is not slowing down, and doesn't seem to have any intention to do so and that in fact it's speeding up.

A football, a saddle and a board game...I don't see the point you're trying to make...

To counter this seemingly fundamental problem, scientists came up with dark energy. It is not called so because it doesn't reflect light, but because no one really knows what it is, what it looks like, has ever observed it or can certainly predict its existence (that's science for you!). It is this dark energy which acts kind of like anti-gravity, forcing matter away from each other therefore speeding up the expansion of the Universe. Interestingly enough, Albert Einstein came up with a similar theory almost a hundred years ago, only to scrap off the idea later and call it his biggest regret in life. Little did he know that now this theory has been acknowledged by most scientists.

There are however alternatives to that theory, and that is what I wrote above earlier. The time slowing down theory is a substitute to the theory of dark energy. It predicts that time will come to an end, literally. Don't wait for me to describe that for you visually, because physics is physics, and our brains are in no way developed (adapted) enough to visualize anything outside our immediate environment.

"We do not say that the expansion of the universe itself is an illusion," he explains. "What we say it may be an illusion is the acceleration of this expansion - that is, the possibility that the expansion is, and has been, increasing its rate."

"Instead, if time gradually slows but we naively kept using our equations to derive the changes of the expansion with respect of 'a standard flow of time', then the simple models that we have constructed in our paper show that an "effective accelerated rate of the expansion" takes place."

And although the change is infinitesimally small for a person to notice, it makes a difference on the grand scale of the Universe. So if the time really is stopping, then it seems to us that the distant galaxies are accelerating (even if they're not actually).

The scientists have also calculated that it will take billions and billions of years for time to completely stop.

"Then everything will be frozen, like a snapshot of one instant, forever," Prof Senovilla tells New Scientist magazine. "Our planet will be long gone by then."

How unfortunate.


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