"The brain! The brain!" Maria Hernandez, Chief Scientist of the Space Cruiser Unbreakable, ran and screamed from the top of her lungs. Her beautiful red hair fluttered as she rushed through the hallways of the ship, not paying any attention; her face convulsed in a grimace of fear and disgust.
"Maria, please stop. What is wrong?" Captain Gerald Bostaph asked as the Chief Scientist almost ran him over.
"This is horrible! We're all going to die!" Hernandez proclaimed in a very high-pitched tone, rolling her eyes.
"What are you talking about?"
"Murder! Maniacs! They will kill and dismember us all!"
"What murder? Can you please explain?"
"You don't understand. We need to run; it might be too late!"
Captain took the Chief Scientist by the shoulders and shook her. She looked at him as if she saw a ghost. He repeated. Eventually, Hernandez calmed down a little and was able to explain what had happened to her.
Unbreakable was in the middle of the regular delivery service flight, destination Leaga Papala 3-1. The journey had been uneventful so far. This region of the Milky Way had been explored very well. It contained several main transportation arteries connecting the worlds colonized by humans. Hernandez had been working in the Science Lab when she had heard a loud thump behind her back. She had turned around and, to her utmost surprise and horror, observed a human brain on the table. Hernandez had immediately experienced a panic attack and ran away, thinking a crew member had been butchered. This was as much as she remembered.
"Well, okay. Let's go to the Bridge and call in the crew. Then, if someone is missing, we will at least know whose brain it is. Did you ask, by the way?"
"Ask who?"
"The brain, of course."
"No, I didn't. There was no head, just the brain, so...."
"Right."
When they arrived at the Bridge, Navigator Leslie Maynard was already there. Hernandez jumped as she saw the Navigator, hugged her, and screamed how happy she was to find Maynard alive. The Captain had to explain the whole story to the Navigator and then called the rest of the crew to the Bridge.
One by one, they showed up: Senior Engineer Chen, Lieutenant Zuma, Doctor Kim, Chef Stroganov, and, finally, First Maid Rade Lukic. He had been recently demoted from the position of the First Mate by the Captain. It was a punishment for his misadventure at the Exchanges of Zach Zeel, the biggest marketplace of the Milky Way. Lukic had been fooled by some thugs and had traded the cargo full of precious metals for pumpkin seeds. This had given Doctor Kim a new responsibility of growing pumpkins at the Infirmary, while Chef Stroganov had gotten a chance to unleash his creativity in the kitchen. Unfortunately, the loss of precious cargo had pushed back the Captain's retirement indefinitely, and the Unbreakable had to enlist into the delivery business to pay the bills and support the crew.
"Is this everyone?" Captain asked.
"Are you looking for someone else? I don't recall hiring any new crew members," Zuma shrugged.
"Right. Then the question is, what is wrong with our scientist?" Captain looked at Hernandez angrily.
"Nothing is wrong, I swear, I saw it, it was terrible...." Hernandez protested and started to cry.
"I am sure whatever you saw was real," Lukic touched Maria's hand. "This ship is full of miracles...the other day, I found a half-eaten pumpkin near the Battery Unit...there might be some hideous beasts on board...please tell us what has frightened you so much."
Chief Scientist Hernandez repeated her story to the whole crew. Naturally, people did not believe her, but Maria would have none of it. She wrinkled her forehead, squeezed her eyes, and marched briskly toward Maglev capsule, asking everyone to follow her to the Science Lab, promising to "demonstrate the facts."
When they arrived at the Lab, Hernandez turned around and triumphantly pointed her finger at the table.
"Now do you believe me?" she exclaimed, gazing at the people.
"Well, it does appear to be a brain," Doctor Kim approached the table and examined the object. "A human brain."
"How is this possible?" Bostaph frowned. "Who smuggled human brain into the ship?" He looked around. "Lukic, this feels like one of your blunders."
"No, Captain, I have nothing to do with this!" The First Maid protested. "Never saw this...thing before."
"Then how do you explain a human brain on the ship?"
"I don't know...maybe it belongs to one of us...has someone lost a brain recently?" Lukic glanced at his crewmates, who only shook their heads, while Hernandez twisted a finger around her temple.
"Wait a minute...." Lukic said, his eyes open wide. "I have an idea! This should give us the answer!"
"Go ahead," the Captain encouraged.
"Doctor Kim, do you have surgical equipment on the ship?" The First Mate asked the Doctor, who nodded in response. "Perfect, then you should be able to perform a craniotomy on us. Whoever has an empty skull is the owner of this brain. Simple and elegant!" He glanced at the Captain and smiled.
"I am sure you'll be the one without a brain, Lukic," Bostaph said, tightening his lips. "I don't think you've ever had one. Okay, does anyone want to confess?"
The silence was the answer. The people looked at each other, puzzled and confused.
Then Hernandez came to the table and looked at the object intently. She leaned her head sideways and whispered thoughtfully, "What if...no, it cannot be...the probability is way too low...."
"What are you mumbling, Hernandez? Care to enlighten us?" Bostaph said.
"I have a possible explanation, but it is bounding fantastic. No one in their right mind would expect this to happen."
"But it did. So, please, tell us what your theory is."
"Alright." Hernandez sat on the table next to the brain and placed her palm on top of it. This one goes back to the nineteenth century, to the famous physicist Ludwig Boltzmann. You see, if we assume the Universe is in thermodynamic equilibrium, then any organized, low-entropy structure could only appear as a result of a fluctuation, when atoms spontaneously come together and form an object. So, for example, such an object could be a fully developed, functioning human brain complete with memories and thoughts. And the probability of such an occurrence is much higher than the probability of the existence of more complex structures. For example, stars, planets, or human beings. Thus, such an object, called 'Boltzmann Brain', should be a lot more common in the Universe than humans."
"I do not recall a crew member called Boltzmann," Lukic whispered.
"Slow down, Hernandez, would you, please?" the Captain asked. "I appreciate the lecture, but could you tell us in simple language what happened?"
"Yes, sorry. I think we just witnessed the spontaneous formation of a human brain. Just like Boltzmann described."
"So, what you are saying is this...thing has appeared out of nowhere? This is utter nonsense," Lieutenant Zuma said. "I think it's an enemy diversion. They are trying to distract us. The brain needs to be annihilated. Let me test by brand new Matter Disintegrator Gun on this junk."
"Wait, Zuma, I think she has a point," Navigator Maynard interfered. "Do we understand you correctly, Maria? Do you suggest this brain has formed spontaneously on our ship? The atoms just organized themselves this way by pure chance?"
"Yes, this is exactly what I mean, Leslie. Such an event is improbable but not impossible."
"Well, it still doesn't explain whose brain it is," the First Maid protested.
"It is no one's, Rade. It is just a brain. I am sure it is dead by now, but it should have had memories and thoughts in the first instant of its appearance. For example, a memory, although false, of always existing in this Universe," Hernandez said.
"Wow, we could have interrogated it and learned all about the enemy's plans. Too bad you ran away, Maria," Zuma pointed his finger at the Chief Scientist.
"Could this be a result of some malfunction within the Space Compressor?" Senior Engineer Chen suggested. Like most modern spacecraft, Unbreakable was equipped with an engine relying on the ability of space to compress almost infinitely. This technology had allowed reducing actual travel distances dramatically. It had opened up the Universe for humankind without the need to bend the laws of physics with "faster-than-light" speeds or "wormholes."
"Well, it could have...." Hernandez shrugged. "I am not an expert in space compression. But, on the other hand, it might have occurred due to a random fluctuation within the decompression sequence. Hard to say. And why would this malfunction result in the creation of the human brain?"
"Wait, Maria...you said something disturbing...." Maynard wrinkled her forehead. "You said humans are less likely to exist than this monstrosity. So then how come we are all here, we know of a lot more people who exist, but no one has ever encountered this freak before?"
"Good question, Leslie. My opinion is the Universe is not in thermodynamic equilibrium, and processes governing its development and structure are very complex. Much more complex than we can imagine. 'Boltzmann Brain' was created as a thought experiment to demonstrate the absurdity of some of the cosmological theories. To witness the formation of such an object is extraordinary."
"Alright, let's assume you are right, Hernandez," the Captain said. "What are we going to do with this thing?"
"As I said, let me annihilate it. I need to test my new gun." Zuma stepped forward.
"I know a few recipes with brains," Chef Stroganov said. "Beef brains à la Crème, deep-fried veal brains, lamb brains - really delicious! - quesadillas de sesos...I don't know any recipes with human brains, but I am sure we could substitute...."
"Chef, please, we are not eating this monstrosity; it's disgusting," Leslie curved her lips.
"I suggest we airlock it. Let it float gently across the vastness of the Universe, pondering on the futility of its existence and the randomness of cosmos," Lukic looked up, raising his hands.
"Rade, I told you this brain is dead. It won't have any thoughts," Doctor Kim said. "I propose we study it in detail. Structure, composition, responses to impulses. Run all the tests we could imagine."
"I like this! We will be the scientists who first discovered and investigated the Boltzmann Brain. Marvelous!" Hernandez rubbed her hands.
Captain Bostaph nodded in agreement. Then, everybody left the Lab except Hernandez and Kim. They were circling the foreign substance like two vultures sensing their prey.
The next day the Captain called the whole crew to gather at the Bridge. The Boltzmann Brain had turned out to be a fascinating object.
"When we cut it open," Doctor Kim explained, "we have found the internal structure to be a fractal. Self-similar, in other words. The same features repeat themselves on smaller and smaller scales. Think about ice crystals, trees with many thin branches sprouting from thicker ones, or Romanesco broccoli, with small buds made up of many even smaller buds...."
"Romanesco broccoli!" Chef Stroganov exclaimed. "One of my favorite vegetables. Roasted with garlic and lemon. Fantastic in its simplicity. Could we use this brain as a substitute for Romanesco broccoli, Doctor Kim? Is this where you are going?"
"No, Chef, this is not what I meant. And you better focus on finding more pumpkin recipes. We need more variety."
"Yes, indeed, I am sick and tired of your pumpkin soup and pumpkin kasha!" Lukic added.
"You better be quiet, First Maid," Captain scowled. " Considering it was your brilliant negotiation skills that provided us with a cargo bay full of pumpkin seeds. But, Doctor, please continue."
"Yes, I was talking about a self-similar structure of the object. We have not encountered this in any living organism possessing brains. Amazing!"
"So, you are saying this brain is abnormal?" Lukic asked.
"I guess you could call it as such if you'd like...the circumstances of its appearance are quite abnormal as well...we do not know what 'normal' would mean in this situation."
"Anything else, Doctor?" Captain asked.
"Yes, indeed. Something even more fantastic. Maria?"
"Here." Hernandez stepped forward. "In the place where the pituitary gland is located within normal brains, we have found a battery."
"What? A battery? Are you making fun of me?"
"No, sir. It is a solid-state battery, in common use on Earth several centuries ago. And it is in good shape, still working."
"Why in Hell would the brain need a battery?" Bostaph raised his left eyebrow and scratched his head.
"Sir, I have a wild theory," Doctor Kim said. "A normal brain in the human body is powered by the bloodstream pushed by the heart. In our case, there is a brain but no body and no heart. So, it is powered by a battery. It sounds ridiculous, but such is the whole situation."
"Brainpower!" Lukic yelled, throwing his fist in the air. Nobody supported his enthusiasm.
"Well, I guess if a whole brain could appear out of nowhere on a spaceship, then why wouldn't a battery power it? Or a little hamster running inside the wheel?" The Captain mumbled.
"Precisely my argument," Hernandez nodded. "If it is a result of a random fluctuation, anything is permissible. But there is more to this story...."
"More? What other nonsense did you discover?"
"Remember, I said the battery was in good shape. We were able to switch it back on and power the brain."
"For the love of God, did you blow it up?"
"No, sir. But we were able to register a weak electrical signal the brain generated."
"Did you...communicate with it?"
"I wouldn't call it communication...we simply registered a signal. It was repeating itself in a loop. I applied Fourier transform to it and then used a few simple decoding algorithms. It was a phrase."
"A phrase?" The Captain's eyebrows raised so high they almost merged with his hairline. "Are you telling me this thing is intelligent?"
"Sentient brain...empowered...I knew we would find alien life!" Lukic whispered to Navigator Maynard.
"No, sir, not quite. There was nothing except this looping signal, and the brain wouldn't respond to our stimuli either. And then the battery died, and the signal stopped."
"You said it was a phrase. What phrase?" Maynard asked.
Hernandez looked down as if something amusing had appeared on the floor. "Hello, world," she said.
"What? This was the message? 'Hello, world'?" The Captain sat down and grabbed his head with both hands.
"Yes, sir. Please don't ask me why. I have no idea."
"Okay, let's document this encounter and forget about it. This makes zero sense to me, but I'd be thrilled if you ladies receive the fame as discoverers of whatever this phantasm is called....the Boltzmann Brain."
"Thank you, sir!" Hernandez and Kim said simultaneously.
"Maria, something is still troubling me...." Navigator Maynard frowned. "You mentioned the theory suggests the Boltzmann Brain could appear out of nowhere, having memories and thoughts, including a false memory of existing in this Universe."
"Yes, this is correct."
"Then it could imagine it is alive, attached to a body, having a normal life, family and friends, and so on...am I right?"
"Technically, yes. And it has no mechanism to distinguish this illusion from the reality."
"This is all very sad...however, my question is: how do we know we are not Boltzmann Brains ourselves, imagining our existence, each other, Unbreakable?"
"This is a great question, Leslie. Many a book and philosophical treatise have been written on this subject. People invented numerous proofs and methods to establish one is not a Boltzmann Brain. In the end, I believe it is impossible to prove or disprove this proposition. The only thing you truly know and are aware of are your thoughts. These could be the thoughts within the Boltzmann Brain or of a human being responding to external stimuli. We have no way of distinguishing the two. You decide for yourself. I personally am not bothered by the possibility of being a Boltzmann Brain. Even if my life and all of you are illusions, then so what?"
"Wait, wait, wait...I protest!" Lukic raised his hand. "I don't want to be some stupid brain floating in the middle of nowhere. I know myself, I have a body, I am rational...."
"I am happy you think that way, Rade. But Boltzmann Brain could think the same as well."
"But we can't all be Boltzmann Brains and have the same illusion going on, can we?" Chef Stroganov said.
"We could, even if this is extremely unlikely. However, this is not important for the argument. If you are a Boltzmann Brain, it is only your illusion you are experiencing. We all could be just figments of your imagination."
"Maria, please stop." The Captain stood up. "This is all very interesting, but I am utterly confused and lost within all these brainy arguments. I need some sanity check. Lukic," he turned to the First Maid. "What did you try to do when we had discovered the edge of the Universe?"
"Tried to hit it with a javelin, sir!"
"This is what I remember as well. Stroganov," he looked at the Chef. "What did you cook for us when we got stuck in the middle of that rogue planet?"
"Eh...tails of giant rats and compacted bio-material, if I am not mistaken."
"Yes! And, Chen, how do you translate Mogo Ri Chu?"
"Mushroom Sunrise, sir. It is the name of the planet we visited."
"Correct. Now, since I just established you all remember the same things I do, this is enough for me to determine I am not insane. I don't care about these crazy theories about brains appearing out of nowhere and floating in space powered by ancient batteries. Based on what I know and experience, I conclude I am not one of them. So, my advice to all of you is to do the same. Get back to work. We have a delivery to make."
"Yes, sir!" Hernandez grabbed Doctor Kim by the hand and whispered, "Let's go back to the Lab...I have a few more ideas on what experiments to run."
"I heard that, Hernandez!" Bostaph said. "You can experiment, but please keep your nutty theories to yourself. I am sure half the crew is now wondering whether they are delusional Boltzmann Brains living in some fantasy."
"Aye, Captain. Just a few more tests, and then we'll put it in a vacuum container to preserve for future studies. This is so incredible!"
"Here is an idea for you. Try to make a new battery and power it again. Perhaps it will communicate more."
"Indeed, we shall try that. Brainpower is a magical thing."