I am delighted to post this additional chapter regarding the science behind The Call of Eternity with insightful, fascinating, yet scientifically grounded explanations from a fellow Wattpad writer and scientist Rainer Salt, who kindly gave up his time to consult with me about many highly theoretical subjects such as the multiverse, wormholes, and fine-tuned constants while I wrote the book. I thought it might be nice to share a special discussion we prepared for readers interested in knowing more about the science underpinning the story. So without further ado, let's dive in to the good stuff! 

Multiverse Theory

E A Carter:

In Part II, Chapter 23, The Anomaly, the story moves into the Immortal Realm where Teshub tells Thoth about the contact he has been receiving from the mortal Urhi-Teshub. Thoth then begins to puzzle apart the various bits of evidence they have regarding their changing world and comes to the conclusion something massive must have triggered the universe to split into two during the wars of gods and men - the split creating an identical parallel universe - although no one is aware of it apart from Thoth who discovered it from anomalies in his mathematical calculations. Teshub has real trouble accepting there could be more than one of him existing simultaneously, and must take it on faith that Thoth has his facts right.

Rainer, can you explain the physics behind what Thoth is talking about (the multiverse theory), and how we ourselves could also be living in a multiverse where there are infinite versions of ourselves living out completely different lives?

Rainer Salt:

In a nutshell, a multiverse is a container that holds two or more universes—like an egg crate holding eggs. The image that Thoth uses in his illustration is even better: Think of our universe as a sphere floating in space. The sphere does not use up all the space, and there is room enough for many other spheres beside it. Humans are, in this metaphorical image, two-dimensional creatures living their lives within the surface of the sphere, and everything we see is two-dimensional, like that surface. We can't imagine a third dimension, we can't look outside the sphere's surface, and we don't have means to leave that surface.

So, even if there's another universe close by, mere inches from us, we wouldn't normally be aware of it.

You're asking me to explain the physics behind multiverse theory.

The concept of multiverse has fascinated physicists and philosophers for decades or longer. It has been the topic of numerous convolute papers, boring lectures, and heated debates. And—as is the case for many controversial topics of science—scientific fervour, arcane maths, and copious amounts of alcohol played a major role in its making.

Does the multiverse exist? So far, there is no definite proof that it does, and it's therefore not established physics. Yet some smart people have tried to come up with explanations (theories) in case such proof does come up.

There are many such theories. Let me focus on one of them here. It's based on quantum mechanics.

Quantum mechanics describes the microscopic world, such as the behaviour of individual atoms, electrons, or photons. At such small scales, some weird things happen.

Let's assume you have an atom of uranium 235. You place it in a box on your desk. That atom is not stable, and it will fall apart. Its "half-life" is 704 million years. So, if you have a pound of that stuff, half of it would have become something else after that time. If you have a single atom in your box, though, it might decay today or it might happily sit in its box for much longer than 704 million years. Quantum mechanics tells you there's a 50% probability that it's still in the box after 704 million years. But it can't tell you if the specific atom you have will live that long.

Are you still with me?

E.A. Carter nods, glassy-eyed.

Good. Quantum mechanics describes the state of your uranium atom in its box as a 'superposition' of an intact uranium atom and a decayed one. This means that, as long as you don't look into your box, the atom is both, a whole and a broken atom. At the beginning, though, its whole version is substantial, and its broken version is nothing but an ephemeral ghost. The longer you leave the box closed, the more substance the ghost will gain while the whole version will start to lose. So, after a few 100 million years, the whole version might be 75% real while its decayed ghost will be 25% real. However, when you open the box then, you'll see only one of the two, and there's a 75% chance that it's the whole version and a 25% chance that it's the decayed one. Let's say it's the whole one: In that case, the whole one will be 100% real again, and the decayed one has disappeared. Otherwise, the reverse will happen, i.e. the whole version will be gone and the decayed version will be 100% real.

But has the decayed one, in the first example, really disappeared then? There's a branch of theories that says it hasn't. Rather, the universe splits into two the moment you open that box of yours and check on your on atom. The two universes differ in that atom: In one universe it's whole, and in the other it has decayed!

That's how a universe splits—bifurcates—into two.

So what? you'll ask. The difference between the two universes is tiny. Who cares about a single atom?

But imagine you're a mad general or even a mad president, and that box sits on your desk. You decide to press your fat, red button depending on what kind of atom you get when you open the box. Easier than tossing a coin! So, in one of the two universes, Earth will be a happy place while in the other one...

Welcome to the multiverse.

Wormhole Theory

E A Carter: 

In Part III, Chapters 56 and 57, Never One of Us, and Six Hundred Days, we learn from the fallen gods of Marduk's back story, and how he came to Earth having traveled across the interstellar distance from his ruined home planet in a vast spaceship along with those survivors of his race. 

On his arrival he discovers Thoth's portals which deftly cross the interstellar distances to other planets. He soon learns he is unable to access them without the accompaniment of a god and never will be granted permission to do so since the use of them grants mortals immortality. 

Denied his chance for immortality by Horus, Marduk begins the one-thousand-year-long war between gods and men, which leads to the gods fleeing and imprisoning themselves within the Immortal Realm. However, before they leave, Thoth instructs Teshub to destroy all the portals, which he does, apart from one he cannot find, the one called Surru, which we later learn Marduk has hidden away deep underground.

Surru portal was the pinnacle of Thoth's achievements, since he was able to harness enough exotic energy to open and sustain a portal which not only crossed interstellar distances, but traversed the universe's barrier into another universe altogether.

Rainer, could you elaborate on the science behind how we are effectively trapped within this universe, but theoretically with enough exotic energy/matter one could open a portal to another universe? 

Rainer Salt:

Just like the multiverse, wormholes are a highly speculative branch of physics. However, the theoretical framework of wormholes (at least of those within our own universe) has developed further.

In their most simple form, wormholes are a solution to the mathematics of general relativity. This means, if you study the mathematical rules of general relativity, you find that there may be wormholes. But this does not mean that they really exist.

The wormholes predicted by general relativity would e.g. connect two black holes. However, such a wormhole would exist for a very short time period only, and it would collapse before even light had the time to travel through it.

Some theories, though, predict that you can keep a wormhole stable if you use "exotic matter" to stabilize it. Exotic matter is a concept having a negative density or mass and that is highly strained. Think of a spring, as we know it, but replace its atoms by some strange form of negative density matter that we've never seen, and then tension that spring by orders of magnitude more that you could ever tension a normal spring. These weird springs could then be used to keep the wormhole open.

We presently don't have the slightest idea of such exotic matter exists, nor how to produce or find it. But, as every sane person knows, there's no such thing as a free lunch. So, if you want a piece of exotic matter, you certainly would need loads of energy to get it and to tension it.

At this point, we'd have created a wormhole spanning two points in our universe. Now, in order to get what's needed for the Surru portal, the wormhole would have to span two universes in the multiverse, i.e. it would have to connect two of Thoth's spheres.

There are theories that predict this might be possible. Basically, in Thoth's picture, the wormholes would have to 'simply' make a bend away from one sphere and tie themselves to another one.

All of this is highly speculative physics. Here's a little story illustrating this.

A bunch of students sits in a classroom. The professor looks at them, sighing inwardly, knowing that most of his audience is just yearning for the period to end.

"One more problem to solve, then you're dismissed for today," he says, hoping to keep at least some of them interested. "A farmer tells you that he has a field of rye. It's of a perfect square shape and has an area of nine square miles. How long are its sides, then?"

One of the students raises his hand. "It's three miles along each of its sides because three times three gives nine." He grins.

The teacher nods, satisfied that the class has finally understood the world of square fields of rye. But then, a girl in the last row waves her arm. He gestures at her. "Yes?"

"There's another rye field that works, too. It has a length of minus three miles along each of its sides. Minus three times minus three gives nine."

The professor groans.

The professor's groaning betrays him—he is a lousy teacher. She has found a perfectly valid solution to his problem, a solution that's fully in line with the mathematics describing square fields of rye.

Just like wormholes are fully in line with general relativity.

But does the existence of this solution predict that such a rye field exists? And how would we interpret a field having negative lengths along its sides, how would it look like? And most of all, could we grow rye on it?

Fine-Tuned Constants

E A Carter: 

Throughout both books and up until Part III in The Call of Eternity, we are given hints that things are not as they should be. In The Lost Valor of Love, prior to the battle at Kadesh, we know the weather is unseasonably cold, extremely wet, and the crops in the fields have rotted in the mud. Later, we learn of a prophecy that all the empires apart from Egypt's will soon face terrible apocalyptic events. Famine, plagues, earthquakes, wildfires, riots, women eating their babies, and entire islands being consumed by the sea. From the prophecy, Istara is compelled to warn Ramesses of the impending ambush coming from the Hittites, choosing to betray her own empire to save thousands in the future by ensuring Egypt does not fall, removing the possibility of the only place for survivors of the impending cataclysm to find refuge.

As we move into The Call of Eternity, we learn Hatti has indeed already begun to suffer from the calamites predicted in the prophecy, and Urhi-Teshub's people are beginning to starve. Later, in Part III of the book, we come much closer to the severity of the situation outside the boundaries of Egypt when Sethi crosses paths with caravans fleeing Ashur (Assyria) and Damas (south of Hatti, east of Amurru) for Egypt. The people, though clearly wealthy, are thin and hungry, they tell of the collapse of their empires, the violence, the rising barbarism, and of the plagues, disease, and pestilence driving them away. Once Istara and Urhi-Teshub arrive outside of Babylon, they are caught in a catastrophic earthquake, which decimates their caravan and shatters the walls and buildings of Babylon. Later when Sethi, Ahmen, and Horus are on their way to meet with the king of Babylon, a strange event happens in the sky.

Toward the end of the book, the anomaly of two Thoths existing in one universe begins to truly take its toll as we move into the final hours remaining before the threads holding the universe together fully unravel leaving it uninhabitable for god, man, or beast. In these hours, Istara witnesses a 2012-style earthquake swallow Babylon; Urhi-Teshub witnesses the city of Tarthuntassa manifesting in the middle of the desert of Elam, displaced from its position far to the west in Hatti; and Istara, Meresamun, and Baalat experience a violent attack of vomiting. Finally, Urhi-Teshub mentions that the vast forest surrounding the crater at Surru erupted into flames spontaneously.

Rainer, can you explain scientifically how the so-called Fine-Tuned Constants could unravel? 

Rainer Salt:

The laws of nature can be expressed in mathematical equations. And these equations contain constants, the so-called fundamental constants, such as the gravitational constant G, which describes how strongly two given masses at a certain distance attract each other. There are about 20 other such constants, such as the speed of light or Plank's constant. They rule the mathematics that describes how planets move, how suns burn, how a fire burns, or why the sky is blue.

Humanity has measured or defined these constants, and we haven't seen them change so far.

But are they really constants? Could different universes in the multiverse be governed by different constants? Or could these constants change within a universe, maybe even locally?

The latter possibility is the one we had discussed for the world of your books. What could cause the constants to drift, and what would the consequences be?

You mention that there are two Thoths in a single universe. One of them has crossed the boundaries of the multiverse. Such a crossing might leave the two universes entangled, and it might start to change the fabric of reality, the fundamental constants of physics. And since the two Thoths are not everywhere at once, but localized, and also the portal is localized to a certain spot on Earth, the distortions might even be local, changing from place to place.

Now, the thought of the fundamental constants changing is a scary one. If, for example, the gravitational constant were to change by a few percent, the weight of water and rock would do the same, and the equilibrium that Earth's crust has settled into would be lost. The consequences might include earthquakes, landslides, fissures forming, or tsunamis. The earth's orbit around the sun would change, too, which might wreak havoc on the climate.

Other constants affect chemical reactions, which might bring unexplainable disease and death. Crops might fail and wither, and livestock might prerish. Electrochemical and electric processes might be affected as well, changing the way signals propagate along our nerves, giving rise to madness and hallucinations.

Local changes in the speed of light would further result in visual distortions and mirages.

All in all, the stuff of nightmares. Or of a good book.

Regeneration Device

E A Carter: 

Marduk has managed to live for an unfathomable period of time, by using what he calls a regeneration device, which is effectively presented in the narrative as a large closed capsule resembling those pods seen in many sci-fi films to keep the crew in stasis while the ship travels the vast distance of light years between worlds. Marduk's can not only can hold him in stasis but it can also regenerate his cells, heal injuries, thus renewing him, and granting him near-immortality. He does mention that he must spend months at a time within the device for the regeneration to work.

I envisioned the device delivering plasma energy via a moving grid of light within a vibrational force field to penetrate the subatomic particles of the body and stimulate regeneration. (I have read plasma energy can greatly speed up the production of new cells, and increase the speed of healing in injuries, but at the level of what this book is talking about we would need something much more advanced than today's small experiments).

Rainer, I know this is all highly speculative and outside the realm of physics, but I am curious what your thoughts are on regeneration technology?

Rainer Salt:

Hmm. This is more a topic of medicine than of physics. As far as I understand, a young body has tremendous powers of healing and self-repair. Over time, though, it loses this capability. And at some point, it starts to fall apart.

I've recently attended a conference where I heard a talk by Aubrey De Gray, a scientist working on immortality. He described aging as the result of seven factors, such as cell death, and finds that all of them can be influenced by today's technology. Perfecting these techniques is, for him, just a matter of time, and not too far away.

DNA damage appears to be one of the major processes of aging. Maybe DNA therapy, such as by introducing suitably engineered viruses into the human body, might provide a tool to repair DNA in the human body.

So rather than using plasma energy, I'd imagine that device to be a vat of chemicals, viruses, or nano-robots, which work on the body submerged therein.

But this is definitely not my field of expertise.

And I wonder if we would really want such technology. I doubt that Earth is strong enough to support humans living 70 years, and I dread to think what would happen if we lived for 700 years.

E A Carter: 

Thank you so much, Rainer! Dear readers, I hope you will check out his profile (the link to his profile is at the top). He is not only a knowledgeable scientist, but a great author as well, his stories fun, clever, and addictive. I hope you will dive in for yourself to see!