by Jason Ayres
This was where it started to get complicated. If he had returned to the new universe, the one in which she had eaten the tuna, why didn’t he find another version of himself there? Had that Josh also travelled to the past, changing sandwiches over as well? Were there now thousands of universes, all with different Alices eating different sandwiches, with Josh repeating the same actions over and over again in an infinite loop?
If that were true, the only way to have prevented this would have been not to conceal his presence the first time he went back in time. He should have told himself what he was doing and not to do it again later. But how would that work out? Would they end up with two versions of Josh in the same universe?
The only way to find out was to carry out a further experiment. Discussing it with Alice, they worked out a plan. The next afternoon, in the lab, they decided that Josh would travel back exactly half an hour, from 2.30pm to 2.00pm, and that they would be waiting for him.
2.00pm arrived and no Josh appeared from the future. If one was coming, he wasn’t coming into this timeline.
At 2.30pm, Josh made his jump back to 2.00pm and found another Alice and another Josh waiting for him. He was expected. This seemed to suggest that this was indeed a different universe.
Next, they eagerly waited to see what would happen at 2.30pm. There were two versions of Josh in the room during that half-hour, and the three of them spent the time discussing what might happen when the half-hour was up.
At exactly 2.30pm, something unexpected happened. The Josh that had come back from the future stayed exactly where he was, but the version that had originally been there disappeared. This they just could not explain. Was some higher power at work, not allowing multiple versions of one person to exist in the same universe, or was it simply a case of physics that was beyond their comprehension?
Even Josh and Alice, with all their experience in this field, struggled to get to grips with comprehending it all. Eventually, they concluded that the experiment meant that three different universes were now in existence:
1) A universe where Josh had not travelled back in time at all.
2) The universe Josh had travelled to, and stayed in, when his counterpart vanished.
3) The universe Josh had originally travelled from, where the Josh who had vanished from universe 2 had ended up.
There would therefore be an Alice and a Josh in all three universes, but not necessarily the ones they had originally started with. As Alice in the second universe observed over dinner that night, he technically was no longer the man she had married.
They also theorised that the same thing happened when Josh returned to the future via the tachyometer after his trips further back in time.
It was easy to get bogged down in these theories, but no one ever said time travel was simple. Josh had spent years reading every scrap of text he could find that had ever been written about grandfather paradoxes, causal loops and countless other problems related to the existence of time travel.
No scientist, movie or novel had ever really resolved these things satisfactorily. Josh felt that he had got further than most of them, but he ought to have done. He had the benefit of real-life experience.
Now he knew that the other universes existed, he wanted to find a way to navigate between them. What had happened in those worlds Alice and Lauren had been dreaming about? He was determined to find out how they had been created and how communication between them was possible.
Were those dreams really subconscious thoughts, filtering their way through like coffee dripping through a percolator? How would that work? Science had made it a possibility in the current universe – people were already controlling cybernetic implants with their brains. If minds really could communicate between universes then the human brain was even more amazing than already thought.
He was particularly interested in the timeline where Lauren had been killed by Dan in 2029. How much difference would that have made to the world since? How far out would the ripples from the epicentre of that event have spread by 2055?
He had recently incorporated the time factor into his Gardner measurement scale. He theorised that the longer ago something happened, the greater the change. He remembered reading somewhere once that the vast majority of people in Britain were descended from William the Conqueror. If that were true, then what if he had died as a child? The world would be full of completely different people.
The same could be said of anyone who had procreated, really. If you assumed an average of two descendants per person, then after a few hundred years you’d be in the realms of millions of potential descendants.
Josh was unaware of the precise events surrounding Lauren’s demise in that other universe, but they had almost certainly happened. If he could find his way to that timeline he could meet up with the other members of the team. They would be able to fill him in on the details of how the timeline had changed after her death.
With the time-travelling element of the tachyometer perfected, he turned his attention to trying to find a way to traverse the universes. It took a further five years to get to this point. During those five years he had taken hundreds of trips back through time, including his helicopter mission to come to Alice’s rescue in the snowy wastes of the Cornish coast.
Now he was all set to make his first trial runs at travelling into a parallel world. He had already made a couple of very short sideways jumps under laboratory conditions, but now he wanted to try something more ambitious. He and Alice had discussed it in great detail, but he also wanted to run it by his friends.
Thus, on a fine summer’s evening in 2055, he walked into The Eagle and Child, close to his laboratory in Oxford, to meet Charlie and Peter for a drink.
Josh and Charlie had grabbed a table in the part of the pub known as The Rabbit Room. Here, literary greats of the past such as C. S. Lewis and J. R. R. Tolkien had gathered more than a century ago. Charlie’s writing career was blossoming and he felt inspired being in a place where such esteemed writers had once drunk.
Peter was returning from the bar with the drinks, lager for Josh and Charlie, bitter for him. Absent from that meal at Mario’s, on his return he had been fascinated to hear about Josh’s time travel research during his long absence. Now he enjoyed nothing more than meeting up at his favourite pub with his two former pupils to talk time travel.
“The thing I love about this place,” said Peter, “is that it’s barely changed since Tolkien’s time. Perhaps we ought to travel back and have a pint with him sometime. Speaking of which, it’s also one of the few places in Oxford where you can still get a decent pint of proper English beer.”
“I’m surprised they even sell it,” said Josh. “Doesn’t everyone drink lager these days?”
“You’d be surprised,” said Peter. “This isn’t one of your new robot bars down Park End Street. Look around you.”
Glancing around the room, Charlie and Josh had to concede he was right. The pub was full of literary-looking types, the majority supping pints of traditional ale, and the bar was manned by a real barman, not a robot. There was something quite refreshing about being in such a place.
“I went in one of those robot clubs last week,” said Josh. “It was one of the younger fellow’s leaving do and he insisted. There’s something pretty weird about watching those robogirls gyrating about on poles, knowing they aren’t real women. They are getting so realistic now you can hardly tell the difference.”
“If I went somewhere like that, Kaylee would kill me,” said Charlie. “Not just because of me going there in the first place, but she’s totally against these robots being used as sex objects. Apparently one of her colleagues got caught shagging one of the cleaning bots in a stationery cupboard at work a couple of weeks ago. He was sacked for gross indecency.”
“What about the robot?” asked Josh, “Did they sack that, too?”
“It was just doing as it had been told,” replied Charlie. “Apparently this bloke had found a way around its firewall
to get at the adult options.”
“It’s a sign of the times,” said Peter. “Like you say, they are barely distinguishable from humans, so it’s bound to happen. The way things are going, I think it’s inevitable these robots are going to take over the world eventually.”
“You mean rise up, kill all the humans and take over society?” asked Charlie. “Bit of a cliché, isn’t it? People have been predicting that since Asimov’s time.”
“Nothing so dramatic,” said Peter. “But you can’t deny what’s happening all around us. These robots already have the equivalent processing power of a human brain. Within the next twenty years, they say we will have the capacity to upload our entire brains into one of their bodies, memories, consciousness and emotions, everything that makes us human. Can you imagine the implications of that?”
“I can see the advantages,” said Charlie. “No more aging, no more illness. We’ll be able to live forever. It can’t come soon enough for me, I can tell you. I’ve been having terrible trouble with my back lately. Really playing up it has been.”
“You’re starting to sound middle-aged, Charlie,” said Josh.
“I am middle-aged,” he replied. “And I’m well and truly starting to feel it.”
“You won’t have any of those problems when we are all robots,” said Peter. “Anything that goes wrong can be fixed just as easily as taking a car to a garage.”
“What about the finer things in life, though?” asked Charlie. “You know how much I love my food and drink. I can’t say I’ll relish being a robot. Plugging into a socket to charge myself up is no substitute for a nice drop of claret and a bit of Camembert.”
“True, but it’s better than being dead,” said Peter. “Anyway, enough of this idle chit-chat. I want to hear what Josh has got to tell us on the time travel front.”
“It’s pretty exciting stuff, actually,” said Josh, enthusiastically. “I’ve made a major breakthrough in the time bubble research and I’m ready to embark on my boldest adventure yet.”
“Past or future?” asked Charlie.
“Not necessarily either,” replied Josh – “Same time – same place – different universe!”
“So you’ve finally cracked it, then?” said Peter. “You’ve figured out how to traverse the multiverse?”
“Indeed, I have,” remarked Josh. “Travelling through the time bubbles definitely creates alternative realities, as we always believed. Recently I’ve found a way of recording each universe’s signature each time I travel through time.”
“That must have taken some figuring out,” replied Peter. “How did you do it?”
“It’s quite simple really. I just adapted some of the technology they’ve been using on that amazing new space telescope the Australians have created.”
“The one that can view the entire universe?” asked Charlie. “I was reading about it in the e-paper the other day. It’s not even been launched yet, has it?”
“No, but Alice did some work on the design, so she’s been involved with the trial runs. You wouldn’t believe the things this can do. It makes the Large Hadron Collider look like a penny-farthing.”
“Such is the ever-developing nature of technology,” remarked Peter.
“Which is fortunate for me,” replied Josh. “To sum it up, without going into a lot of technical mumbo-jumbo about cosmic microwave background radiation, it is now possible to measure not only the exact age of the universe, but also the exact number of atoms in it.”
“That’s incredible,” replied Charlie.
“Isn’t it just?” replied Josh. “I’ve been able to incorporate the same technology into the tachyometer. I can now take these measurements myself, at will, just from the device. Don’t ask me how, just accept that I’m amazing and let’s move on.”
“Of course,” said Charlie. “Show off to your heart’s content. Why change the habit of a lifetime?”
“Thank you,” said Josh. “So, recently I’ve started taking measurements of the exact size of the universe each time I’ve time-travelled and discovered something rather interesting. It seems that each time I travel in time, I’m changing the size of the universe.”
“How come?” said Peter, eager to hear more.
“It seems that every time I time travel, the number of atoms in the universe changes ever so slightly. The differences are microscopic on a universal scale, but they are there, nonetheless. Firstly, I noticed that each time I travelled into the past the universe appeared to be slightly larger than it should have been. I soon worked out why.”
“Was it because there were now two of you in it?” asked Charlie.
“Got it in one,” said Josh. “Every time I travelled into the past, I was taking an additional version of myself back into time, increasing the size of atoms in that universe by the amount that constitutes me, my clothes and anything I took with me.”
“Yeah, that makes sense,” said Peter. “It’s pretty obvious when you think about it.”
“What initially didn’t make sense was the difference in the size of the universe that I returned to,” continued Josh. “These differences were much smaller, but they were definitely there. Now why do you think that might be?”
The blank faces on Peter and Charlie pleased Josh. They clearly couldn’t figure this one out, which meant he would get the satisfaction of telling them.
“Allow me to explain,” said Josh. “Quite simply, I wasn’t the same size when I returned as when I left. We’re all gaining and shedding atoms constantly. If I ate anything when I was there, then those atoms came back to our universe. And, without being unduly crude, if I went to the toilet, I left those atoms behind.”
“Speaking of which, this beer’s going right through me,” said Peter. “The old bladder’s not what it was. I’m afraid. Since I haven’t upgraded to a super-efficient cybernetic waste disposal system yet, I’m in urgent need of losing some atoms on my own. I’ll be back in a minute.”
“That’ll give Josh a chance to get another round in,” said Charlie.
Once they were all back at the table, Peter was impatient to hear what Josh’s plans were.
“So, all this theory is great, but let’s cut to the chase. What are you going to do with your latest findings?”
“Quite a lot, as it happens,” replied Josh. “I’ve adapted the tachyometer to use this information to allow me to travel not only in time, but also between the universes. I even know roughly how many universes there are.”
“How many?” asked Charlie.
“Millions upon millions,” replied Josh. “And the number seems to be increasing exponentially.”
“So, that’s more than you can possibly have created yourself, then?” asked Charlie.
“Well, me personally, yes, but what about all the other Joshes in all the other universes? What if lots of them are doing the same as me? It’s perfectly possible. I’ve already travelled to two other universes, and they were remarkably similar to this one. I met two other versions of myself there, both of whom were conducting similar experiments.”
“And that’s assuming you are the only person who had worked out how to do this,” added Peter. “Are you aware of any other time travel experiments going on anywhere in the world?”
“I’ve heard whispers the Australians are trying to develop something,” said Josh, “but nothing more than that.”
“Because this is pretty powerful stuff,” continued Peter. “If someone else got hold of this technology, they might not just want to use it for research, like you are. In the wrong hands, there could be catastrophic consequences from changing things in the past or in other universes.”
“But not for us,” said Josh. “Remember, every trip into the past creates a different universe. You are quite safe here in yours – what has happened here won’t change. What I want to do now is find out what some of those other universes are like, and there is only one way to do that.”
“You’re off to explore some of these other worlds, th
en?” asked Charlie.
“That’s the plan,” replied Josh.
“Isn’t this a little bit dangerous for you?” asked Peter. “What if something went wrong with the tachyometer and you couldn’t find your way back?”
“I’ve thought of that,” said Josh. “That’s why I’ve created three of them. Alice is going to track where I go using one of the other tachyometers. If I don’t come back, she can come after me using hers and bring me a spare. Failing that, I’ll find my other self in the other universe and get him to help me get back.”
“Assuming he knows what you are talking about,” said Charlie. “You can’t guarantee he will have developed the same technology as you.”
“That is a potential problem,” conceded Josh. “Look, I’m not naïve enough to not realise there are risks involved. Future Josh hinted there would be danger at Mario’s, remember? But he made it back OK, didn’t he? If scientists throughout history hadn’t taken risks, the human race would still be living in the Dark Ages.”
“It could be riskier than you think,” added Peter. “What if you emerged in a world so different to ours that you couldn’t survive in it? Say, a world where the dinosaurs never died out and super-intelligent reptiles might kill you and eat you?”
“I hardly think that’s a possibility,” said Josh. “How could I have made that happen? I haven’t been further back in time than 1974.”
“Maybe you haven’t, but someone else might have,” replied Peter.
“Well, that’s just a chance I’ll have to take,” said Josh. “I did say it was going to be an adventure. Wouldn’t you take it, given the chance?”
“I’m not as adventurous as you,” said Charlie. “I like my home comforts too much, but I guess if you could guarantee it was safe, I wouldn’t say no to the chance of seeing some of those other worlds.”
“Same here,” said Peter. “It’s only fair after all the time we’ve spent helping you over the years.”