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Physicists Recreate 'End Of Time' in Lab
Technology Review | The Physics arXiv Blog | kfc | 2011 July 26

Ever wondered what would happen if the dimension of time came to a sudden end? A new experiment reveals all.

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One of the most exciting areas of science is the emerging field of spacetime analogues. This is the discipline in which physicists play around with systems that have a formal mathematical link with general relativity.

For example, changes in the way electrons move in graphene as it is cooled are identical to the changes that may have occurred in the universe soon after the big bang. So physicists can use cool graph to test theories about the universe's earliest behaviour.

Another example is the formal mathematical analogy between the behaviour of light in electromagnetic space and in spacetime. That's interesting because physicists have recently learnt how to manipulate electromagnetic space using metamaterials. That has allowed them to create the electromagnetic equivalents of quantum foam, the big bang and even the entire multiverse.

All of these experiments are jaw droppers (imagine making black hole in the lab). That's why it's hard to top them.

But Igor Smolyaninov at the University of Maryland likes to have a go. Today, he explains how he's created an experiment that models the end of time.

The idea is straightforward (no really!). Metamaterials can be made to behave like ordinary space with two dimensions of space and one of time. But they can also be made to behave like other types of spaces, with two dimensions of time and one of space, for example.

Smolyaninov points out that an interesting situation occurs when these two materials are place end on. If a time dimension is perpendicular to a space dimension, it simply hits a dead end. In other words, time runs out.

"This situation (which cannot be realized in classic general relativity) may be called the "end of time"," he says in a paper with a couple of colleagues.

Not content with merely thinking about such a scenario, these guys have gone ahead and built it using a plastic called polymethyl methacrylate or PMMA deposited in stripes onto gold film. The light takes the form of plasmons moving across the surface.

So what happens at the end of time? Smolyaninov says that the electromagnetic field simply diverges, which is something of an anticlimax in an experiment so pregnant with sci-fi potential.

But interesting stuff nevertheless.

Hyperbolic metamaterial interfaces: Hawking radiation from Rindler horizons and the "end of time"

• Igor I. Smolyaninov, Ehren Hwang, Evgenii Narimanov
  arXiv.org > physics > arXiv:1107.4053 > 20 Jul 2011

The Big Crunch: Physicists Make Time End
Wired Science | Brandon Keim | 2011 July 28

This is the way the world ends: not with a bang but a higher harmonic generation.

The same researchers who used exotic substances called metamaterials to make a benchtop Big Bang have mimicked the end of time, also known as the Big Crunch.

Light traveling through metamaterials is described mathematically by equations used to describe space and time, allowing physicists to probe cosmic questions in a controlled manner.

In this experiment, the photons underwent a “higher harmonic generation,” or a sudden rise in frequency and energy. Put another way, “the end of time looks very hot,” said electrical engineer Igor Smolyaninov of the University of Maryland.

Smolyaninov and colleagues Ehren Hwang and Evgenii Narimanov wanted to probe the Big Crunch, a postulated scenario in which the universe contracts back upon itself, eventually collapsing into a black hole.

As described July 20 on the physics preprint website arXiv, their metamaterial consisted of a plastic called polymethyl methacrylate embedded in a grid upon gold film.

As photon-electron waves called plasmons flowed through the gold they followed the rules of a universe with two dimensions of space and one of time, said Smolyaninov. Flowing through the plastic, they followed the rules of a universe with one dimension of space and two of time.

When the substances are placed perpendicular to each other, as on this grid, then a dimension of time runs up against a dimension of space. As plasmons excited by a beam of laser light coursed through the plastic and hit the gold, time effectively came to an end.

Plasmons diverged at that boundary, their photons rising in energy in accordance with predictions.

In future studies Smolyaninov plans to add quantum dot semiconductors to the metamaterial, which he says would allow it to better simulate the center of a black hole.

There he hopes to find an analogue for Hawking radiation, a quantum phenomenon predicted by Stephen Hawking to exist at the edge of black holes.

“Normally, if you have a black hole and a particle near the event horizon, that’s the end of the story. But according to Hawking radiation, one particle is absorbed and another let out. In classical physics, this is forbidden, but in quantum physics it’s allowed,” said Smolyaninov. “Black holes don’t just absorb everything.”

I don't think i have the time to figure it ou........

Beyond wrote:I don't think i have the time to figure it ou........

I was worried about the 'Recreate'. I wasn't aware the 'End of Time' had already happened. I'm always the last to know.

Isn't it nice to know you'll never be late anymore

bystander wrote:

Beyond wrote:I don't think i have the time to figure it ou........

I was worried about the 'Recreate'. I wasn't aware the 'End of Time' had already happened. I'm always the last to know.

I found the "recreate" thing very interesting, too.

One very important reason for me to become interested in space was that I realized that it was so humongously big. It gave me an enormous kick to realize that the stars are actually suns that are so far away that it gave me an incredible sense of marvellous vertigo to try to imagine just how far the stars would have to be in order to look as faint as they do.
The most horrible thing anyone has ever told me about space is that it might collapse in a Big Crunch.


Hey, that's just a building collapsing. Come on. I was talking about the sky collapsing.


The idea of the sky actually falling down on me - and never mind that I personally would have been gone for billions or trillions of years by the time when a possible Big Crunch could happen - was the most unnatural, loathsome and revolting thing I had ever heard about space. (Supermassive and angry black holes, seriously, can't hold a candle - no, they can't hold a matchstick - to the idea of the entire universe collapsing in on itself.)






Yeah? What are you staring at, you smilie? If the Big Crunch comes, it will reduce your staring face to a mathematical point, along with the everythingness out there.

Have you read The Hitch-Hiker's Guide to the Galaxy? Remember this part?

The Earth.

Visions of it swam sickeningly through his nauseated mind. There was no way his imagination could feel the impact of the whole Earth having gone, it was too big. He prodded his feelings by thinking that his parents and his sister had gone. No reaction. He thought of all the people he had been close to. No reaction. Then he thought of a complete stranger he had been standing behind in the queue at the supermarket before and felt a sudden stab - the supermarket was gone, everything in it was gone. Nelson's Column had gone! Nelson's Column had gone and there would be no outcry, because there was no one left to make an outcry. From now on Nelson's Column only existed in his mind. England only existed in his mind - his mind, stuck here in this dank smelly steel-lined spaceship. A wave of claustrophobia closed in on him.

England no longer existed. He'd got that - somehow he'd got it. He tried again. America, he thought, has gone. He couldn't grasp it. He decided to start smaller again. New York has gone. No reaction. He'd never seriously believed it existed anyway. The dollar, he thought, had sunk for ever. Slight tremor there. Every Bogart movie has been wiped, he said to himself, and that gave him a nasty knock. McDonalds, he thought. There is no longer any such thing as a McDonald's hamburger.

He passed out. When he came round a second later he found he was sobbing for his mother.

Yeah? The Earth is gone in The Hitch-Hiker's Guide to the Galaxy. Arthur Dent's parents and sister are gone, and his supermarket is gone, and Nelson's Column is gone, England is gone, New York is gone, the dollar is gone, every Bogart movie is gone, and you can't get a McDonalds hamburger anymore anywhere in the entire universe.

Yeah? Big deal. Not. Not when you compare it with the Big Crunch. Because if the Earth is destroyed you still have the galaxy. You still have Alpha Centauri, a Sun-like star, and you still have 18 Scorpii, an even more Sun-like star. You still have 55 Cancri, a Sun-like star with a system of planets.

But with a Big Crunch, everything is gone. Everything. The Earth, the Sun, the solar system, the Milky Way, the Andromeda galaxy, the Local Group, the Virgo Cluster, the Coma Cluster, the great wall, the Lyman Alpha forest, the cosmic microwave background. The hydrogen and helium. The coal and the oxygen and the water. Everything. Even the emtiness of space is gone. Even the "volume" of space is gone. Everything is gone.
Gone, John Ralston? What do you mean? You've got streets, a bus, trees, buildings, hallways.. what do you mean, gone?


I googled "nothingness" and got this picture:








Nothingness! What do you mean? You have a nice bridge, a streetlamp, a bicycle, snow - what do you mean, nothingness?
















Yes, slightly better. But if you can imagine, let alone see, a rectangle of darkness, then you haven't got nothing. You haven't come close to nothingness.











Personally I find the idea of a Big Crunch unspeakably abhorrent. It amazes me that people seem to hope for a Big Crunch.

And the scientists here seem so enthusiastic about the concept that they want to "recreate" it, as if the Big Crunch had already happened. Let alone as if it was overwhelmingly likely that a Big Crunch will actually happen at all, given what we know about the acceleration of the expansion of the universe.

But of course, if the universe won't oblige and give us a Big Crunch, then some Big Crunch enthusiasts will do their best to give us a small Big Crunch in the lab.


Wheee!!! Let's go for that Big Crunch ride again!!!










Ann

The Big Crunch That's one way to find out what the universe has been hiding, behind all this time.

When I was a kid, everybody knew the Universe was expanding.

Then when I was in high school, they said the Big Crunch would come.

Then a few years ago, they discovered that the expansion of the universe was not slowing down but speeding up, and it would lead to the Big Freeze.

Now we're back to the Big Crunch again?

Will somebody stop the room from spinning, please.

Voyager3 wrote:When I was a kid, everybody knew the Universe was expanding.

Then when I was in high school, they said the Big Crunch would come.

Then a few years ago, they discovered that the expansion of the universe was not slowing down but speeding up, and it would lead to the Big Freeze.

Now we're back to the Big Crunch again?

Will somebody stop the room from spinning, please.

http://asterisk.apod.com/viewtopic.php?f=31&t=22115