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IMAGINE you are floating along in space. It is quiet and cold, serene but slightly terrifying. Suddenly, you feel a tug, faint at first, but getting ever stronger as it pulls you towards an empty region of the sky. Before you know it, you have entered a black hole. 鈥淭hat鈥檚 when the universe starts to go bizarre on you,鈥� says Priyamvada Natarajan at Yale University.

With the publication of the first ever picture of a black hole this week, any residual doubt that these monsters of space-time exist is banished. But as to what happens inside one 鈥� well, there physicists are still mightily in dispute. So what are your possible fates, should you ever be so unlucky as to have a close encounter of the black hole kind?

All objects exert a gravitational pull on one another, but for the most part, this force is pretty weak. In the case of black holes, the pull is so strong that nothing 鈥� not even light 鈥� can escape. A black hole is so massive that time itself starts to warp. You wouldn鈥檛 feel anything different as you fell in, but to anyone watching, you would appear to slow.

Circling down the drain of this cosmic plughole, all the photons being pulled alongside you would create a stream of blinding light orbiting a hole of total blackness 鈥� as we saw in the Event Horizon Telescope team鈥檚 image. Two freaky effects would colour your final approach: a looming darkness would wash over your eyes as the black hole seems to grow in size much more quickly than you would expect, and the surrounding stars would start to distort and bend.

This is your last opportunity to escape. Any further, and you will cross the event horizon, the line where the black hole鈥檚 gravity is too large to resist.

鈥淏y the time you are able to see the event horizon,鈥� says Natarajan, 鈥測ou can see starlight bend around it.鈥� Curved streaks of light would wrap around the black hole, but as you accelerated through the point of no return, the intensity of the gravitational field would change the nature of the light you can see. If your neck muscles had the strength to let you take one last look over your shoulder, all the starlight behind you would appear to come together to form a single reddish dot. Meanwhile, the quiet of outer space would turn to total darkness and you would feel that you are falling downhill, says Natarajan 鈥� 鈥渆xcept downhill is everywhere鈥�.

And then your body would undergo spectacular tortures. The gravity inside a black hole increases so quickly that it wouldn鈥檛 just crush you, but pull apart every part of your body at different speeds, resulting in 鈥渟paghettification鈥�. If you fell in feet first, your ankles would stretch away from your knees before your neck elongated into a strand of linguine, but the difference in time would be small enough that you probably wouldn鈥檛 notice. 鈥淚t would happen in the blink of an eye, which may not be the best expression since your eyes are going to pop out,鈥� says Natarajan.

What happens next to the newly spaghettified, eyeless, accelerating you?

To stay where you are, go to A

To wait for a black hole burp, go to B

To seek a white hole exit, go to C

To try to radiate yourself away, go to D

A: Stay where you are

The laws of thermodynamics are ruthless. Even a black hole can鈥檛 escape their judgement. According to the second law, the amount of entropy or disorder in the universe can never decrease. So when your disordered body falls in, the entropy it contains can鈥檛 just be wiped away. It has to be accounted for by an increase in the entropy of the black hole itself. But if a black hole has entropy, it must have a temperature, so 鈥� like any object with a temperature 鈥� it has to radiate heat.

How can radiation escape an inescapable object? In 1974, Stephen Hawking came up with a workaround, inventing a type of radiation that now bears his name.

Rather than emerging from the black hole鈥檚 heart, this Hawking radiation is made up of particles and their antiparticle twins that pop into existence near the event horizon. Such pairs of particles and anti-particles are always springing into existence all over the place. These subatomic twins are intrinsically linked, with any change to one immediately affecting the other. In the language of quantum mechanics, they are said to be entangled.

By virtue of this subatomic conspiracy, any anti-particle that falls into a black hole will have a partner particle that survives, radiating away and reducing the black hole鈥檚 energy. But this leaves us with an alarming consequence: at some point, the black hole will radiate away entirely, taking you with it.

That disappearing act violates another fundamental tenet of theoretical physics: that information can鈥檛 just vanish. Even if information is destroyed in one form, like a book burning when it gets thrown on a fire, that information is still retained in the particles of smoke and ash that survive it 鈥� albeit in a form much harder to read. Physicists rely on this continuity to access information about the past and make predictions about the future. If it could be conjured in and out of thin air, all the physics we know of would be moot.

If a black hole can destroy information, it can destroy all trace of you. Game over.

Try again from the beginning (or perhaps head to 鈭�)

B: Wait for a black hole burp

Some physicists have suggested that you could cling on inside a black hole as it evaporates via Hawking radiation (see A), before getting belched out in its dying breath. That way at least some of your information wouldn鈥檛 be lost forever, but held in captivity for aeons as the black hole slowly leaks away.

At some time in the distant future, depending on the black hole鈥檚 initial size, the event horizon would become so small that even a single wavelength of light could no longer squeeze inside. At that point, radiation associated with your remains would be burped out, leaving nothing behind but the empty space where the black hole used to be.

But there is a fatal flaw to this prolonged game of hide and seek: the black hole doesn鈥檛 get to decide how quickly it pumps out radiation; the laws of thermodynamics decide. The more radiation something emits, the smaller it should get, and the smaller it gets the less radiation it can emit. By the time the black hole gets small enough to vomit out its last meal, there wouldn鈥檛 be anything left to expel. The black hole would go out with a whimper, not a bang, and any residual traces of your existence would be long gone.

You bet on a burp 鈥� and lost. Goodbye.

Try again from the beginning (or there is always the 鈭� option)

C: Seek a white hole exit

Just as black holes permit no object to escape their pull, hypothetical objects known as white holes can鈥檛 hold anything together. One idea is that every black hole is connected to a white hole via an interdimensional tunnel known as a wormhole. Fall into one, and you will, eventually, get thrown out the other.

For Carlo Rovelli at Aix-Marseille University in France, however, there is a way to make this happen without even needing a wormhole. Instead, he suggests that every white hole used to be a black hole, meaning that at some point in the far future, your remains could be vomited up as the black hole flips back into a white hole. But how does this transition happen?

Once a star collapses to form a black hole, its constituent atoms get so close together that they start being subject to the laws of quantum physics. And this can lead to some strange and counter-intuitive phenomena. The most important of these is called quantum tunnelling, which says that particles have a small but non-zero chance of travelling straight through an otherwise impenetrable barrier. For particles falling into a black hole, says Rovelli, this means they could theoretically pass straight through the 鈥渟ingularity鈥� of infinite density at its heart, and bounce back out. 鈥淲hat falls inside a black hole gets to the centre, and it鈥檚 like it hits a wall, because according to Einstein鈥檚 theory, it cannot come back,鈥� says Rovelli. 鈥淏ut quantum theory allows it to 鈥榯unnel鈥� through and re-emerge.鈥�

This creates a scenario in which space-time bounces back outwards, creating a white hole. To an outside observer, this process would take billions of years, but inside, owing to the black hole鈥檚 enormous gravitational pull, time would be speeded up. 鈥淭he time it would take you to fall down the centre, go through and bounce up the other side would be milliseconds,鈥� says Rovelli. 鈥淚f we could look inside, you would look frozen.鈥� And there鈥檚 just a chance that this frozen you 鈥� or frozen particles of you 鈥� might make it out of the white hole.

Congratulations, you found a way out of the black hole. Possibly 鈥� and you do look rather a mess

Want to try again from the beginning?

D: Radiate yourself away

As Stephen Hawking identified, black holes are constantly emitting radiation. So what if, instead of being destroyed or hidden away for eternity, your identity was leaking out in the form of this Hawking radiation? Sad to say, this actually makes things a lot more complicated.

Hawking radiation is made up of virtual particles that blip into existence near the event horizon with one entangled partner particle sucked in while the other escapes (see A). But if that is the case, quantum mechanics presents us with an unpalatable paradox. We already know that particles of Hawking radiation are in an entangled state with their partners that just fell in. But because Hawking radiation contains information on every single particle that has already fallen in (and those particles were entangled with radiated particles of their own), any outgoing particle must also be entangled with the Hawking radiation that preceded it.

Quantum mechanics doesn鈥檛 allow this kind of polyamory. A fundamental principle known as the monogamy of entanglement says that particles can鈥檛 be entangled with two things at once. If your information wants to exit the black hole via Hawking radiation, something else needs to happen to it.

You are attempting to violate the laws of quantum physics. Choose immediately between these three options

To brave the firewall, go to X

To take a space-time leak, go to Y

To split the universe, go to Z

X: Brave the firewall

One way out of your quantum dilemma is to conjure up a blazing wall of fire. If this firewall existed just inside the event horizon, it would break the entanglement between any infalling particles and their partners on the outside of the black hole.

Trouble is, this combustible barricade is completely incompatible with Albert Einstein鈥檚 general theory of relativity, which predicts that a black hole鈥檚 event horizon shouldn鈥檛 feel any different from the space around it. According to Einstein, the pull of gravity should always be indistinguishable from the consequences of acceleration: if you were in a rocket accelerating quickly through space, you would feel as if gravity were pushing you back in your seat. This equivalence principle is supposed to hold on either side of the event horizon, which means you shouldn鈥檛 notice anything out of the ordinary as you cross it.

But even if we do allow the existence of such a barrier, it鈥檚 not a pretty way out. If you were to cross it, you would be fried to a crisp, and so would any other infalling matter.

You braved the firewall 鈥� and fried. You might want to try 鈭� as your get-out clause, or go back to the start and聽try again

Y: Take a space-time leak

One idea around black holes is that they connect to a dimension-spanning cosmic wormhole. But what if instead of feeding into a raging white hole on the other side (see C), the universe鈥檚 plumbing is a lot less spectacular?

Leonard Susskind of Stanford University in California and Juan Maldacena at Princeton University have imagined a kind of wormhole that branches away from a black hole in many directions like the root network of a tree. Each tiny pipe is only big enough for individual photons of Hawking radiation to emerge, allowing the black hole to evaporate, while skirting the paradoxes of the firewall and information loss. The information is conserved as it exits the black hole down one of these roots, and no firewall is created because nothing crosses back over the event horizon. What鈥檚 more, because we have done away with partner particles, the monogamy of entanglement never needs to be broken. Win-win!

Unfortunately, there is a problem. According to Aidan Chatwin-Davies at KU Leuven in Belgium, this process violates the core principle of quantum physics that information cannot be destroyed (see A). If you toss a quantum entity into a black hole, and what comes out is thermal radiation, the information it contained has vanished from our universe. And that is a big cosmic no-no.

You tried to violate information conservation 鈥� and that never goes well. Maybe try 鈭�?听

Or go back and聽try again

Z: Split the universe

What if our universe isn鈥檛 the only one? It is a radical idea, but one that proponents of the many-worlds view of quantum mechanics take seriously. Every time a quantum process takes place, they say, the universe splits, creating a different parallel world for every conceivable future.

That means that when you jump into a black hole, every conceivable outcome is taking place somewhere in some parallel plane of existence. That means that you can appear to violate the fundamental principle of information conservation (see A), so long as the way you do that is compensated for in another cosmos.

The different branches of the many-worlds multiverse are all correlated, says Aidan Chatwin-Davies at KU Leuven in Belgium, and that means your fate has now been spread across multiple versions of the multiverse. So pick your poison! You could be burning up in firewalls, falling through white holes, leaking into the fabric of space-time or possibly never falling in at all. The laws of physics may break down in the universe that we can see and interact with, but across the billions of potential realities, sanity is restored.

Congratulations (maybe) 鈥� one of you (probably) survived

You can also still try again

鈭�: It wasn鈥檛 a black hole after all

There is a get-out-of-jail-free card for all these unpalatable black hole scenarios: to simply reimagine what a black hole is. In classical physics, there is no way to stop matter from collecting, turning into a star and then collapsing into a black hole. Gravity just won鈥檛 stop.

Enter string theory. It starts with the idea that matter isn鈥檛 made of fundamental particles, but instead is composed of tiny strings. In the crushing gravity where a normal black hole would be, these strings would get tangled together. 鈥淭he more energy you put into a system, the bigger the ball of strings becomes,鈥� says Samir Mathur at Ohio State University. 鈥淚t never really makes a black hole. It鈥檚 a planet-like object made out of strings, and a planet doesn鈥檛 create the information-loss problem.鈥�

You would still die a pretty terrible death if you fell onto a fuzzball like this, but instead of becoming part of nothing, you would become something. First, you would get warm as you approached it. As you passed the event horizon and continued towards the massive string ball, you would be torn apart and your body would turn into a bundle of strings just as you reach the surface.

After you get absorbed into the ball of strings, you would start spreading out across the surface of the black hole, mixing in with the other strings there. 鈥淎t that point, you would be pulled apart and you wouldn鈥檛 be living any more. But your strings would be vibrating,鈥� says Mathur. Your thoughts and memories would be long gone, but the stuff that made you would be part of one of the most bizarre places in the universe. Not a bad way to go.

THE END 鈥� until some theorist dreams up something better.