What if yesterday hasn’t disappeared? What if we’ve simply turned the page?
The Photograph
She found the photograph in a cardboard box that had spent the better part of thirty years in the attic. Its edges had curled slightly, and the colors had faded into that peculiar yellow of old memories. In the picture, a little girl stood barefoot in the grass, grinning at the camera while a golden retriever sat patiently beside her.
She remembered that day. The dog had been named Rusty. Her father had taken the photograph, and somewhere beyond the camera, her mother had been calling everyone inside for dinner.
The little girl was seven years old. The woman holding the photograph was sixty-three.
She studied the child’s face and felt something she couldn’t quite explain. She knew things that little girl couldn’t possibly imagine. She knew about the years ahead, the people she would love, the mistakes she would make, and the losses she would endure. She knew Rusty would be gone before her thirteenth birthday, that her father would die when she was twenty-nine, and that the little girl smiling into the camera would someday become a grandmother.
But the child knew none of those things. For her, that summer afternoon was the present. Tomorrow was a mystery, and the future stretched ahead, unwritten and full of possibilities.
The woman touched the photograph.
Where had that afternoon gone?
We tend to imagine that moments disappear as we move through life. Yesterday is gone, tomorrow hasn’t arrived, and the present is all we’ve really got. Time marches forward, carrying us along whether we’re ready or not. We can remember the past and imagine the future, but neither seems to exist anywhere except inside our heads.
It’s a perfectly reasonable way to look at things. After all, we’ve spent our entire lives watching the world behave that way.
But what if we’ve misunderstood something fundamental? What if time isn’t a river carrying moments into oblivion?
What if it’s more like a book?
What If Time Is a Book?
Imagine reading a novel about a fellow whose life unfolds across eighty years. In the opening chapters, he’s a mischievous little boy exploring the woods behind his home. In the middle, he’s raising a family, building a career, and discovering that adulthood isn’t nearly as much fun as he thought it would be. By the final chapter, he’s an old man sitting on his porch, wondering where all those years went.
As the reader, you’ve followed him through his entire life. You’ve watched him grow up, fall in love, make mistakes, and eventually grow old. You know things about him that his younger self couldn’t possibly have imagined, and you’ve watched the consequences of his decisions unfold across decades.
But here’s something interesting. That little boy in Chapter One hasn’t gone anywhere.
You can flip back to page twelve and find him right where you left him, climbing a tree on a warm summer afternoon. His parents are still young. His childhood dog is still alive. And he hasn’t the faintest idea what awaits him in the chapters ahead.
Every chapter is still there, tucked between the covers. Only your position in the story has changed.
Now, I know what you’re thinking. It’s a book. Of course the earlier chapters are still there. But humor me for a minute. What if the universe works something like that? What if yesterday hasn’t gone anywhere? What if your tenth birthday, your first kiss, and that unfortunate haircut you wore in high school are all still out there somewhere, occupying their own chapters?
And what if tomorrow is already written, waiting for us to turn the page?
Sounds a little crazy, doesn’t it? Well, here’s where things get interesting. Some very serious physicists and philosophers have entertained ideas that aren’t entirely unlike our imaginary book.
One interpretation is called the block universe. It treats the past, present, and future as parts of a larger structure called spacetime. Rather than imagining the universe as a single present moment constantly replacing itself, this view suggests that events at different times may all belong to the same four-dimensional reality.
That doesn’t necessarily mean the future is predetermined in the way a novelist determines the fate of a character. Nor does it establish that every moment exists in quite the way our imaginary pages do. Those are questions that take us into the philosophical interpretation of physics, where even brilliant minds can disagree.
But suddenly our little book doesn’t seem quite so ridiculous.
And it raises a question I’ve often wondered about. If every chapter is part of the same enormous story, why do we experience only one at a time?
Someone Reading Over Your Shoulder
Let’s stick with our imaginary book for another minute.
You’re sitting in your favorite chair, reading a novel, when someone wanders into the room and starts reading over your shoulder. Personally, I find that a little annoying, but we’ll let it slide for the sake of the argument.
You’re both looking at the same page. The words are identical, and the characters are doing exactly the same things. But are you experiencing the same story?
Maybe you see the hero’s latest decision as an act of courage, while your companion thinks he’s being a complete idiot. You sympathize with one character, while the other reader finds that character insufferable. And suppose your companion has already read the book. They know what’s coming. You don’t. Suddenly, even though you’re looking at the same page, the two of you are experiencing that moment very differently.
We see something similar in everyday life. Two people can witness the same event and come away with entirely different memories. One remembers a wonderful evening. The other remembers an argument that nearly ruined a friendship. Our minds don’t simply record the world like video cameras. They interpret it, attaching meaning and emotion to everything we experience.
But let’s take our book analogy one step further.
What if consciousness is more like the reader than the character?
The character is stuck inside the story. He can’t jump backward twenty chapters to relive his childhood or skip ahead to discover how things turn out. The reader, on the other hand, can revisit an earlier chapter, compare it with a later one, and recognize connections the character hasn’t yet discovered.
Now, I’m not suggesting we can actually send our consciousness wandering backward through time. We have no reliable evidence that such a thing is possible. But it’s an intriguing thought, especially when we consider how little we understand about the deepest nature of conscious experience.
Maybe our physical brains are bound to the present because they’re part of the physical world. But is consciousness necessarily limited in exactly the same way?
I don’t know. And I find that question rather difficult to leave alone.
Einstein Ruins Everybody’s Schedule
For most of human history, time seemed simple enough. The sun came up, the sun went down, and eventually somebody invented clocks so we could be late for appointments with greater precision.
We came to think of time as something universal. A second was a second, whether you were sitting in your kitchen, standing on a mountaintop, or floating somewhere between Earth and the Moon. Somewhere, we imagined, the universe must have an enormous clock keeping everything in perfect order.
Then along came Albert Einstein and spoiled that comfortable picture.
Einstein’s theories of relativity revealed that time doesn’t behave quite the way we assumed. The amount of time measured between events can depend on motion and gravity. Two clocks following different paths through the world don’t necessarily agree on how much time has passed when they’re brought back together.
Now, before your eyes glaze over, consider something you probably use every day.
Your phone.
When you ask it for directions, it relies on signals from satellites orbiting high above Earth. Those satellites carry extraordinarily accurate clocks, and here’s the strange part: their clocks don’t run at precisely the same rate as clocks down here on the ground.
The satellites are moving quickly, which makes their clocks run more slowly relative to Earth-based clocks. They’re also farther from Earth’s gravitational pull, which makes their clocks run faster. The gravitational effect is larger, so the two influences don’t quite cancel out. Engineers have to account for the difference, because even tiny timing errors can create significant navigation errors.
Imagine telling someone a couple of centuries ago that a little device in your pocket could guide you across the country, but only because engineers understood that time passes differently in space.
They’d probably have you examined by the village physician.
And here’s another oddity. With sufficiently precise clocks, scientists can measure differences in the passage of time between clocks separated by surprisingly small changes in height. Even two clocks sitting at different elevations don’t necessarily accumulate exactly the same amount of time.
The differences are tiny in everyday circumstances, of course. You won’t become noticeably younger by moving your bedroom to the second floor. But the principle is astonishing.
There is no single universal clock keeping perfect time for everything in existence.
And relativity reveals something even stranger. Events that one observer considers simultaneous may not be simultaneous for another observer moving differently. In other words, the universe doesn’t provide one universally agreed-upon present moment for everyone, everywhere.
Which makes you wonder what we really mean when we say something is happening right now.
Einstein apparently wondered about that, too. In a letter written shortly after the death of his friend Michele Besso in 1955, he reflected on the distinction between past, present, and future, describing it as a stubbornly persistent illusion.
He wasn’t claiming that clocks don’t work or that we can casually wander into yesterday. But his understanding of spacetime had led him toward a view of reality quite different from the one we experience while making breakfast.
Perhaps the present isn’t quite the solid, universal thing we’ve always imagined.
And if that’s true, what happens to yesterday when we’re finished with it?
Why Broken Eggs Stay Broken
Here’s another peculiar thing about time.
Drop an egg on the kitchen floor and you’ll have a mess to clean up. Wait an hour, a week, or a thousand years, and that egg isn’t going to leap off the floor, put its shell back together, and settle neatly onto the counter. Although after a thousand years, I suspect the condition of your kitchen will be the least of your worries.
But why doesn’t the egg put itself back together? Why doesn’t spilled coffee climb back into the cup? Why doesn’t smoke gather itself into a cigarette, or a puddle of water spontaneously become an ice cube on a warm countertop?
We know these things don’t happen. We’ve lived long enough to trust that much. Yet the reason behind this everyday certainty leads us into one of the strangest mysteries in physics.
It has to do with something called entropy.
You’ve probably heard the word before. It’s often described as a measure of disorder, although physicists mean something more specific. Roughly speaking, entropy has to do with how many different microscopic arrangements can produce the same overall condition.
Think about our unfortunate egg. There are relatively few arrangements in which its shell is intact and its contents are neatly contained. There are vastly more arrangements in which everything is scattered across the floor. When enormous numbers of particles are involved, the odds overwhelmingly favor the kinds of arrangements we associate with spreading, mixing, and breaking apart.
In an isolated system, entropy overwhelmingly tends to increase. Heat spreads out, things mix together, and broken eggs remain stubbornly broken. This is closely related to the second law of thermodynamics, one of the most dependable principles in science.
Scientists call this familiar tendency the thermodynamic arrow of time.
But here’s the part that makes me scratch my head. Does entropy increase because time moves forward? Or do we call one direction forward because that’s the direction in which entropy increases?
Those might sound like the same question, but they aren’t.
Many fundamental equations describing nature work much the same way whether time runs forward or backward. Yet the world we experience seems absolutely determined to move in one direction. We remember yesterday, not tomorrow. We watch glasses shatter, but never see the pieces spontaneously leap back into place.
And there’s an even bigger mystery lurking behind the broken egg. If entropy has been increasing throughout the history of the universe, then the universe must have started in an extraordinarily special, low-entropy condition.
Why?
We have theories, but no universally accepted explanation for why the early universe began in that particular condition. It’s one of those questions that seems simple enough until you start looking for an answer.
So the next time you break an egg, consider that you may be witnessing one small example of a mystery that reaches all the way back to the beginning of the universe.
Although I still recommend cleaning it up.
The Needle in the Groove
If you’re old enough to remember vinyl records, you’ll recall the peculiar little ritual of listening to music.
You’d carefully remove the record from its sleeve, place it on the turntable, and lower the needle into the groove. With luck, you’d hear music instead of the horrible scraping noise that meant you’d just done something expensive.
The needle traveled across the record, playing one song after another. But here’s the interesting part: the first song didn’t disappear when the second song began. It was still there, encoded in the grooves. You could lift the needle, move it back toward the beginning, and listen to that first song again.
Now imagine that time works something like a record.
Perhaps our experience of the present is like the needle moving through the grooves. We hear only the music being played at that moment, even though the record contains the entire album. Maybe yesterday is still there, just as the first song remains on the record even after the needle has moved on.
Of course, a record player is just a record player. It doesn’t prove that the past still exists or that we can somehow revisit it. And unlike a record, we have no known way to lift ourselves out of the present and drop back into an earlier moment.
Still, I like the analogy because it turns our ordinary assumptions upside down. We’re accustomed to thinking that the past disappears because we can no longer experience it. But those aren’t necessarily the same thing.
Just because we can’t return to yesterday doesn’t automatically mean yesterday has ceased to exist.
And if the entire record does exist, what determines where the needle happens to be?
The Prisoner of the Present
Have you ever noticed how strangely time behaves in your own life?
When you’re a child, summer vacation seems to last forever. Christmas takes approximately eleven years to arrive, and the final ten minutes of a school day can feel longer than an entire afternoon.
Then you grow older. Suddenly, Christmas arrives every fifteen minutes, summer is over before you’ve properly enjoyed it, and you find yourself wondering how another birthday managed to sneak up on you.
The clocks haven’t changed. But something certainly has.
Our brains don’t experience time as a steady procession of identical seconds. Attention, emotion, memory, and expectation all influence how long a moment seems to last. A frightening experience can seem to unfold in slow motion, while an enjoyable evening can disappear before you’ve had a chance to appreciate it.
Dreams make things even more interesting.
You can wake from a dream feeling as though you’ve been through an elaborate adventure. You’ve visited strange places, met unusual people, escaped terrible dangers, and perhaps even fallen in love. Then you glance at the clock and realize that your sense of how much time passed in the dream may not be particularly trustworthy.
Our sense of time is clearly more complicated than simply watching a clock.
Which brings me back to something I’ve often wondered about.
What if the brain doesn’t merely help us experience time? What if it also limits how we experience it?
Think of the brain as a character in our imaginary book. It exists in a particular chapter, experiencing the events unfolding around it. It remembers earlier chapters and tries to anticipate what might happen in the next one. But it can’t simply step outside the story.
Now consider consciousness.
Most of us take it for granted that our awareness belongs to our brains, and there’s extensive scientific evidence connecting conscious experience to brain activity. Changes in the brain can change what we perceive, remember, feel, and even how we understand ourselves.
Yet there’s a deeper question that philosophers and scientists continue to wrestle with: Why should physical processes in the brain produce the subjective experience of being someone at all?
We can study neurons firing, electrical signals traveling, and regions of the brain communicating with one another. But explaining exactly how those physical events give rise to the feeling of being you remains a difficult problem.
What if there’s more to the relationship than we currently understand?
And here’s the really intriguing possibility.
What if our brains are prisoners of the present, but consciousness is something more like the reader of the book?
It’s speculation, certainly. We have no established evidence that consciousness can leave the brain or explore earlier moments in time. But the idea is fascinating because it challenges something we’ve rarely had reason to question.
Perhaps we’re so accustomed to experiencing time in one direction that we’ve mistaken our way of experiencing it for the only way time can possibly exist.
Or perhaps our brains are doing exactly what they’re supposed to do, and the mystery lies not in consciousness escaping time, but in why we experience a moving present at all.
Either possibility leaves me with more questions than answers.
And I rather like it that way.
The Pages We Leave Behind
The woman returned the photograph to its box.
For a few moments, she’d been seven years old again. Not literally, of course, but in that peculiar way a memory can pull you backward through the years until something long forgotten suddenly feels as real as yesterday.
She could almost smell the freshly cut grass. She remembered the rough warmth of Rusty’s fur beneath her fingers, her father’s laughter, and her mother’s voice calling from the house.
Then the memory faded, and she was sixty-three again, standing in an attic surrounded by the accumulated possessions of a lifetime.
She looked once more at the little girl in the photograph. Somewhere in the years between them, that child had become the woman. Countless ordinary moments had slipped past unnoticed, while others had left marks that would never fade. There had been wonderful days she’d wished could last forever, and terrible ones she’d thought would never end.
Had those moments vanished forever?
Maybe. Or maybe the universe is considerably stranger than we’ve ever imagined.
Perhaps time really is a river, carrying yesterday away as tomorrow approaches. Perhaps it’s more like a book, with every moment occupying its own place within a much larger story. Or maybe we’re completely wrong about both.
I certainly don’t pretend to know.
But I find it comforting, somehow, to imagine that the happiest moments of our lives might not be entirely gone. That somewhere in the vast structure of reality, a summer afternoon might still exist, complete with the laughter of people we’ve loved and the warmth of sunshine on our faces.
It’s a lovely thought, even if we have no way of knowing whether it’s true.
The woman smiled at the photograph and carefully returned it to the box. She couldn’t turn back the years, and she knew better than to spend her remaining ones wishing she could. There were still chapters ahead of her, after all, and she intended to enjoy them.
But for one fleeting moment, she wondered whether the years were really gone—or whether she’d simply reached a different page.
And somewhere, in a chapter she could no longer open, a little girl was still laughing in the summer sunshine.
At least, that’s one possibility worth wondering about.
Sources & Further Reading
For readers interested in exploring the science and philosophy behind these mysteries:
Albert Einstein and the Nature of Time — Einstein’s 1955 letter to the family of Michele Besso, reflecting on the distinction between past, present, and future.
National Institute of Standards and Technology (NIST) — Research and explanations of relativity, atomic clocks, and the effects of gravity on time.
Stanford Encyclopedia of Philosophy: Thermodynamic Asymmetry in Time — An exploration of entropy and why time appears to move in only one direction.
Stanford Encyclopedia of Philosophy: The Neuroscience of Consciousness — An examination of the relationship between brain activity and conscious experience.
