Ryuichi Fukazawa / EyeEmGetty Images

- In new search, a scientist avoids the problem of the three bodies.
- The three-body problem refers to the inability of astronomers to follow the collision course of three stars rushing toward each other through space.
- To better predict the fate of these celestial bodies, the secret is to treat space like a leaky balloon made of Swiss cheese.

Imagine the Earth and the Moon careening together around the solar system. It is clear what will happen as the moon continues to circle our planet, completing its full orbit each month. Now picture – like in the 2011 film *Melancholy–*a rogue planet rushing towards Earth.

#### ➡ You think science is hard. U.S. too. Let’s go together.

With this third celestial body in the mix, all bets are off. Astronomers have spent centuries pondering this thorny and persistent “three-body problem” to no avail; even though scientists track the movements of each “body” from nanosecond to nanosecond, they still cannot reliably predict how the three stars will change.

But while scientists cannot say what will happen in a *specific *In the case of the three-body problem, they reduced the puzzle by creating statistical predictions for many what-if scenarios, like the one mentioned above.

Today, a physicist goes even further in this probabilistic approach, by proposing a potentially revolutionary solution. His theory, published on April 1 in the journal *Celestial mechanics and dynamic astronomy, *uses a fairly abstract concept involving chaos between co-orbiting bodies.

## What exactly *Is* Chaos?

To break this down, let’s take a look at what physicists really mean when they talk about “chaos”. It’s much more complicated than our earthly designs: a teenage bedroom with piles of clothes piled on the ceiling, for example, or a restaurant kitchen after dinner service.

Because the yawning void of space is truly filled with countless interacting forces at all times – from solar winds to the mighty gravity of distant stars – the result is sheer mathematical chaos. By definition, this is a truly unpredictable outcome. In popular culture, it is best known as the butterfly effect.

So how do mathematicians and cosmologists deal with the three body problem when it is based on chaos? They choose to study approximations of the *probability* of certain results, rather than just trying to solve for each individual circumstance. And to help them study the problem in an abstract way, cosmologists have moved to “phase space,” a custom 21-dimensional arena for complex questions.

Say what? *Live Science* __Explain__:

In this domain, each spot represents a possible configuration of the three stars: it is a 3D position, a 3D speed and a mass for each of the three bodies. A three-body event (like a star flying towards a pair) begins at a certain point in phase space and traces a path as it evolves from one configuration to another.

Once you add physical limitations, like the law of conservation of energy, there are only eight dimensions left in phase space. From there, chaotic situations crawl like tree branches through all their possible outcomes, and this is where statisticians find their numerical values.

## A game of chaos kickball

Still, it’s hard to focus on the chaotic region in this phase space. Scientists know that when you have three celestial bodies in co-orbit, they can go from chaotic to regular motion by expelling one of those bodies, at least briefly, for a short period of time.

Physicist Barak Kol of the Hebrew University of Jerusalem may have been a game-changer in this eight-dimensional phase space. Rather than focusing on a boundary between the chaotic region and the region of regular motion, Kol proposed a theoretical hole in the chaotic system.

So, rather than seeing the phase space as having *some* Regularly handed out times when chaos turns on and off, Kol says these issues actually form holes like Swiss cheese. The holes represent the places where chaos is most likely to turn on and off.

Over time, as the three bodies interact in the chaotic region, it becomes more and more likely that one of the bodies will find a hole and launch into chaos. Kol wraps this complex theory with an arc through a function he calls “chaotic absorptivity,” or the probability that a group of two celestial bodies goes into chaos when a third body enters the picture.

This content is imported from {embed-name}. You may be able to find the same content in another format, or you may be able to find more information, on their website.

The next step is to run lots of simulations of single stars colliding with paired stars. This will sense the mathematical limits of Kol’s Swiss cheese holes, one at a time. Hopefully this distinction in chaos theory is a building block for a refined mathematical model that could solve the three-body problem.

## 🎥 Now watch this:

This content is created and maintained by a third party, and imported to this page to help users provide their email addresses. You may be able to find more information about this and similar content on piano.io

Source link