Dark energy is a mystery to scientists; we know how much there is and some of its properties. About 70% of the universe is made of dark energy, with dark matter making up about 20%; normal matter adds up to only about 5%.

"Dark energy" is the consequence of one of Einstein's predictions about space, that "empty space" can possess its own energy. This form of energy could cause the universe to expand faster as time goes on, as it appears to be doing.

(Rate of expansion since birth of universe)

This diagram reveals changes in the rate of expansion since the universe's birth 15 billion years ago. The more shallow the curve, the faster the rate of expansion. The curve changes noticeably about 7.5 billion years ago, when objects in the universe began flying apart as a faster rate. Astronomers theorize that the faster expansion rate is due to a mysterious, dark force that is pulling galaxies apart.

This idea lines up well with what quantum physicists were thinking about empty space, that it is full of temporary particles continually renewing and ending. Meanwhile, astronomers were trying to understand why the universe appeared to undergo an accelerated expansion - a growth spurt.

Dark energy is suspected in both theory and observation.

Krauss and his colleague James Dent suggest that it is possible that, by making the key observations in 1998 leading to the formation of this modern dark energy theory, we have reset the clock on dark energy production.

In 1958, Russian physicist L. Khalfin discovered that after an extremely long time, the probability of a quantum system having survived stops falling exponentially and switches to a slower rate of decline. This means that if the false vacuum of the universe survives to the switching point between the two rates, it will effectively become eternal. This is because the false vacuum is known to grow exponentially fast, and past the switching point it will be created faster than it can be eaten away by any decay, he says.

According to Krauss, the smaller the energy gap between the false vacuum and zero, the earlier the switching point between the two rates. And - surprise, surprise - we live in a universe where the vacuum energy is just above zero, so we could be well past the crucial switching point.

At first glance, this seems like good news for us because it would mean our universe is on track to survive forever. However, things may not be as good as they seem, Krauss says. At the quantum level, whenever we observe or measure something, we reset its clock and stop it decaying - something known as the quantum Zeno effect. Our measurement of the light from supernovae in 1998, which provided evidence of dark energy, may have reset the false vacuum’s decay clock to zero - back to a point when the likelihood of its surviving was falling exponentially over time. “In short, we may have snatched away the possibility of long-term survival for our universe and made it more likely it will decay,” says Krauss.

If it's true that we've doomed the universe by looking too closely, you can bet that aliens would not be happy about it. Sure enough, in his 1992 novel Quarantine, science fiction writer Greg Egan wrote about how a quirk in human neurology causes us to collapse the waveforms of anything we observe - and as a result, we've been destroying vast swaths of the cosmos with our telescopes. For this reason, they isolated us from the rest of the universe with the "Bubble:"

The Bubble is a perfect sphere, twelve billion kilomerters in radius (about twice the orbit of Pluto) and centered on the sun. It came into being as a whole, in an instant...

The Bubble presents an immaterial surface which behaves, in many ways, like a concave version of a black hole's event horizon. It absorbs sunlight... and emits nothing but a featureless trickle of thermal radiation.