What Actually Are Space And Time?

billions of years from now abroad, the last of a great Dark Heights civilization throughout its Days of Glory, its Engineers worked on entire star systems, dismantling planets and asteroids to build an immense Interstellar Empire, but now, In the Twilight of his

time

, all this has already passed. Around them, the universe is dying as the last stars fade over countless millennia, the sky has continued to fade into an eternal night, the aging Universe trapped by desolation and decay, so in the Dark They wait for the end long before they can do it. They had realized

what

was coming, they knew that the Universe was on a path of inevitable decay, they methodically searched for one last place to wait for eternity and embarked on their last great engineering feat around a lost and lonely black hole, they built a new home with demolished worlds as raw material, they built a shell to completely enclose the darkness and within this thin shell, barely resisting the gravitational grip of their savior, they eked out a living, the waning light of dying stars raining down on their final home as their swirling black hole was harvested to fuel their existence, but more than that, the black hole in their hearts gave them the greatest gift of all, because the black hole gave them

time

.

No one remembered the name of the great scientist who had discovered the nature of time, except astronomical engineers. He knew that time was not the same throughout the cosmos and here, within the immense gravity of the black hole, time passed more slowly as many years passed outside, mere moments passed within the immense sphere and so the last members of the civilization watched the future unfold before them, but knew that they had only delayed, not prevented, their ultimate demise and that the Darkness would inevitably envelop them forever. Of course, this story is little more than speculation, but it is based on a scientific idea that changed our universe.

More than a century has passed. Since Einstein's relativity shook our understanding of time and

space

, but how does it really work and

what

does it really mean? Both time and

space

seem so common, so obvious, so everyday, but beneath their ubiquity lie a multitude of unanswered questions, questions that Einstein's theories are only beginning to answer. What is space made of? Does time and Will exist? The search for your ultimate nature leads to sudden clarity. All space and time become more elusive. Einstein offered them lunch and they accepted, so he moved a pile of papers from the table.

We opened four cans of beans with a can opener, heated them, put a spoon in each one and that was our lunch Albert Einstein was a busy man and often skipped lunch and that was in 1915 in the century since our lives have become more chaotic and that This is why a children's meal service like hellofresh, our sponsors today is an excellent option. hellofresh offers high quality fresh produce direct from the farm to your door with over 55 weekly meal options ideal for everyone and especially if you want to stay fit and healthy. I'm a big fan of fitness and eating the right food, but honestly, sometimes there just aren't enough hours in the day and a microwaveable meal seems like the only option.

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All around them, civilization had done everything it could to move forward to postpone the inevitable attempts. They could only bend reality, they couldn't break it. Behind all this, surely, everything is an idea so simple and beautiful that when we understand it in a decade. century or millennium we will all tell ourselves how it could have been otherwise how we could have been so stupid what is space the question seems almost meaningless when children we learn to describe our environment as up down left right back and forth we call it It is three-dimensional and we are free to explore each dimension, but what is this universal platform on which we develop our lives?

It is a question that occupied the minds of the first philosophers in the 4th century BC. Plato declared that space was the nurse. to become a medium in which everything existed but without its own qualities and his student Aristotle agreed that a vacuum was impossible, but more than 2,000 years would pass before our concept of space was born with the arrival of the 17th century. science was crystallizing, the processes of the universe were being codified into physical laws and the understanding of these physical laws was evolving from myths and stories to the language of mathematics, of course Isaac Newton was at the forefront of this revolution, but Before it enters our stage, It must first begin with the ship in 1632.

Galileo published his seminal work Dialogue Concerning the Two Principal World Systems. At the time he was around 60 years old and had already had multiple run-ins with the Roman Inquisition over his claims that the Earth rotated. the Sun, so he decided to sidestep the controversy and spend the intervening years quietly consolidating his countless ideas about space and the cosmos into one book and one moment within this book, Muses on a Boat, more specifically, the life of a Sailor looked below deck into a windowless cabin with plates, knives and a goldfish in a bowl on the table and a collection of birds, flies and butterflies.

What does this say about that experience tied up in the port? The cabin is an image of serenity. All is calm as the goldfish swims happily in its bowl. The bowl on the table folds and the cutlery remains in place and the flying creatures flutter happily, but finding itself in a rough sea, the cabin shakes and falls with the plates. from the ship and the cutlery is torn from the table. Water pours out of the Goldfish Bowl into the calm sea with sails full of wind, the ship would speed up the sailor would feel this change and see things sliding off the table, but when the wind finally subsided the ship would sail smoothly over the crystal clear sea Inside the cabin, everything would be calm.

Serenity would return for the sailor. It was as if the ship was still in port and not moving at all, a fallen plate fell straight to the ground and the sailor sat comfortably in his chair and it was here that Galileo realized something without a window to reveal the truth, There were no experiments that the sailor could do to reveal whether the ship was moving or not, he concluded that there should be no absolute concept of being at rest in space, but rather that everyone should experience smooth, uniform motion in the same way as all uniform motion must feel like simply being Even so Galileo declared that any uniform motion is simply relative to any other uniform motion and with this the first theory of relativity was born.

Galileo's sailor gently floats his boat in seas near the Earth's equator rotating at 1,600 kilometers per hour around the Earth, which in turn orbits the Sun at 67,000 kilometers per hour, which in turn orbits the Milky Way at 720,000 kilometers per hour which in turn travels towards the Andromeda galaxy at 403,000 kilometers per hour and yet feels nothing on this vast journey of millions of kilometers Unfortunately, from his starting point, when publishing the book, Galileo returned to fall out of favor with the church and was found guilty of heresy for his heliocentric view of the cosmos. The work was banned and would not be removed from the church's index of banned books until 1835.

This was not the end, for a few decades after Galileo's fall, two of Europe's greatest minds were arguing about nature. from space. One of them, Isaac Newton, was born in England in 1642, a year after Galileo's death. Of course, he needs little introduction and he is known now as one of the greatest thinkers of his time, perhaps one of the greatest of all time, and he was not forgotten. His opponent Gottfried Leibniz is somewhat less known today. He was born in 1646 in what is now Germany. He was an outstanding thinker of his time. While writing about mathematics and philosophy, he pondered deep metaphysical questions, including one that still haunts physicists and philosophers to this day.

Why is there something instead of nothing. It was in the development of calculus that the dispute between the two men began as Leibniz published his work for the first time. Newton stated. who had stolen his ideas as president of the Royal Society at the time Newton set up a committee to investigate the dispute, unsurprisingly the committee ruled in Newton's favor and thus this animosity carried over to his second disagreement: simple question: what happens to a spinning cube? of water, the space Newton declared was a universal absolute, a rigid stage in which motion took place and both space and time would exist in a universe devoid of matter to experience any motion to argue his point.

Newton asked us to think about a bucket of water if the bucket is at rest the surface of the water would be flat and level but if we spin the bucket the water also spins and its surface becomes curved so Newton asked with spin was relative to an absolute space, something separate from the object itself, so spinning a cube in an empty Universe would also curve the surface of the water, but leibnizing the space in a Empty universe without matter simply did not make sense, the properties of objects. Leibniz stated that they are essential to define their meaning.

Space only had meaning in the relative locations of objects and similarly, time only had meaning when talking about their relative motions without matter. Leibniz said that space and time simply had no role and therefore did not exist. Unfortunately, Leibniz died in 1716 with the argument still in full swing and it was Newton's ideas that fixed absolute space in its own nature without relation to anything external remains always similar and immovable absolute true and mathematical time of itself and -The so-called absolute space and time would be the accepted science for almost two centuries but with the proviso that Galileo's rejection of absolute rest, relativity was still part of the argument but that it only applied to space time was a totally different matter with its implicit direction time appeared. completely different for Newton and Galileo, everyone's clock Throughout the Universe marked with absolute synchronicity a universal beat that ran through each event in the cosmos one second on Earth the same as one second anywhere else because this truth is malleable time or an unbreakable metronome that drags The cosmos forward.

Does time itself have properties or is it defined only by the events that happen in its current? To answer these questions we must begin not with physicists wondering about clocks, rulers and motion, but with the heat in the distant future of the Universe around the aging black hole. our dying civilization sits and waits, sit and wait is all they can do with the passing of the stars. Raw energy had become the most precious thing to preserve what they had. They had slowed down their existence. Every aspect focused on survival while his eyes drowsy. They watched the skies get darker and darker.

The total universal heat, death slid through the cosmos, they realized that time was their greatest enemy. Oh, you can see a cup of tea fall off a table and break into pieces on the floor, but you will never see the cup recover. together and jump back onto the table strange space as the nature of time occupied the minds of many ancient thinkers in ancient Greece Aristotle claimed that time was simply the steps between before and after, while Hindu philosophers viewed time as cyclical from creation to destruction over four billion years, but its true origin remained elusive, as space-time seems to be something obvious, something that is simply present, but it is clearly a different Beast, we cannot, for For example, traveling freely through time, unlike space-time, has a direction, a distinct past, and a coming future, of course.

Scientists can be pragmatic and not worry about the nature of time, along with a ruler, a clockcompletes the experiment as a toolbox, but that doesn't mean we can ignore the question and therefore to fully understand time we first have to think about horses and steam engines. The arrival of the Industrial Revolution presented humanity with a problem: the original engines of civilization, draft animals, such as horses and cattle, were relatively simple things, understanding how much to feed them and how much to work them was easy, a certain number of bales of hay could guarantee the daily work of a well-fed animal, but what about novel machines like a steam engine?

How much work can be obtained from a pile of coal? This was an important question from an economic point of view. Do you even bother replacing a horse with a motor? if it is going to cost more to feed it and it was from this enigma that thermodynamics was born many mines were debating the question of the final efficiency of engines, in fact, at the time of the beginnings of thermodynamics, a typical engine only worked with a three percent efficiency. In a physical steam engine, heat from the fire is used to boil water, but some of the heat from the fire is simply radiated into the air. metal scrapes against metal screeching loud and hot to the touch both forms of energy loss in any physical steam engine this loss of heat as waste is inevitable and in fact within the mathematics of thermodynamics it was discovered that perfect efficiency was an illusion;

The concentrated energy released by burning coal must be degraded as it flows through the engine and some must be lost to the environment; a new measure was finally introduced. to account for this increased entropy of decay and disorder, and it is probability that dictates how this happens, as early 20th century physicist George Gamof put it, the room you sit in. Al reading this book, the air fills evenly from wall to wall and floor to ceiling, and it doesn't even occur to you that the air in the room can unexpectedly accumulate in a far corner, leaving you suffocating in your chair, yet this horrible This event is not at all physically impossible, but it is very unlikely.

Gamoth goes on to give a lead time for such an event billions and billions of times longer than the entire age of the universe. Disorder is always statistically much more likely and therefore, through these new laws of thermodynamics, physicists revealed an inexorable growth of entropy as the universe moves towards a future Universe destined to be more disordered and decaying. than the current one and this applies not only to steam engines but to entire planets, stars, galaxies, filaments, all marching from order to disorder. It was in 1862 when Grim The logical endpoint of these ideas was proposed by Lord Kelvin, who gave his name to the unit of measurement.

Although mechanical energy is indestructible, there is a universal tendency for its dissipation, which produces the depletion of potential energy throughout the material Universe, the result would inevitably be a state of universal rest. and death if the universe were finite and left to obey existing laws and so was this time a Universe in constant death heading towards the inevitable heat death stars going out one by one in a constant march from potential energy to waste Leaving the universe of a billion years Dark and dedicated to one of the great minds to deal with entropy and the arrow of time was James Clark Maxwell, the iconic 19th century Scottish scientist.

His views on thermodynamics shaped our understanding of heat and gases and he did all this with the help of a The demon Maxwell understood the implications of entropy. He knew that if he mixed two gases, one hot and one cold, the result would be hot gas and he knew that the gas would stay hot and mixed instead of separating into two halves, but he was wondering what would happen if we introduced a little demon that can feel all of them. and each of the atoms of the gas. This demon can rotate the atoms, directing the slow atoms to one side and the fast ones to the other, since the temperature of a gas is a reflection of the average speed of its atoms.

The demon could effectively separate the hot gas into two unequal halves, one hot and one cold, the demon seems to have broken the laws of thermodynamics, he took the disordered state of the hot gas and created a more ordered state, hot and cold gas. , and although this is just a thought experiment Discussions about the meaning of Maxwell's demon have been going on for more than 150 years; some have claimed that the demon must be expending energy to sort the atoms in the gas and therefore the total entropy will continue to increase; However, some have proposed that it is not the energy that is important but the fact that The Demon uses information, specifically the velocities of atoms, to make the classification that links the entropy of energy and information.

It may seem a little strange, but over the last three quarters of a century this link has become increasingly stronger and, as any touch of a computer will tell you. Information processing generates a lot of waste heat, but the situation is even more complex, since it is not simply information processing that leads to waste heat. I forget: when we add three and two, the answer is, of course, five, but if I told you one the answer was five and ask what two numbers add up to. You cannot respond similarly within a computer. Logic gates combine electronic signals to do addition while entering two numbers.

They forget when the only answer is spit out. The calculation is irreversible. the lost entries in the universe and in the action of forgetting the logic gates still heat up a little in this way thermodynamics provides us with the maximum limit for forgetting called the terrestrial hour limit, it is the inevitable release of energy when erasing a single bit of information and at room temperature is just over one-hundredth of an electron volt, as was shown experimentally in 2012. Scientists believe that computer chips currently produce thousands of times more heat than this limit, but it is most likely that in 2035 they will reach that minuscule amount of residual heat. increasing the entropy of the universe ultimately throughout the cosmos it is this irreversibility of calculations that drives the increase in entropy forgetting information is therefore an essential ingredient in defining an arrow of time does this mean that for yesterday and tomorrow they have meaning should we forget?

The existence of the future is implicitly linked to our inability to remember, and it is now that we can return to our lonely civilization on the brink of universal heat death in the distant future, when all useful energy is exhausted and entropy is at its maximum. any meaning and that is why we have reached a turning point the foundations of modern time and space can only take us so far and although they are useful, another Revolution is coming, a new order that will lead directly to the last days of our lonely hole black. world and as we continue on our journey we will have to explore a new time and a new space within its black hole shell.

Many civilizations resigned themselves to their fate and made their way to the end, but some curious minds with their waning energy still wondered about the universe. Great books that had been around for almost an eternity told them how space could bend and curve. At the center of these books was the story of light. They knew that the speed of light was immense and had used it to help measure their empire. that light was a limit they could never break no matter how hard they tried, and they knew that the speed of light had been the first step in the long journey to understanding how the Universe really works the next time you are outside on a cold night. summer.

Turn your head towards the zenith almost vertically above you will be shining the brightest star in the northern skies Liar's Vega 26 years away at the speed of light close enough so that there is no return for us short-lived creatures , for no man will ever return home Beyond Vega to greet again those he knew and loved On Earth the speed of light has always been mysterious It was in 1676 when Danish astronomer Olly Roma finally found the answer. Roma was watching Jupiter's moons as they circled the giant planet and timing just when they entered the gas giant's planetary shadow.

He had assumed that the orbits worked like a clock and so he couldn't predict exactly when the moons' eclipses would begin and end, but as he watched the moon IO throughout the year, his predictions getting worse and then better again, it became clear. that the accuracy of his predictions depended on our distance from Jupiter and he needed to include the extra time it takes for light to travel further, so, using data from Rome, fellow astronomer Christian Hikens calculated that light must move at more than 200 and 11,000 kilometers per second, not far from our modern estimate of about 300,000.

The observation from Rome confirmed that light was fast and finite, but precisely what light was, the walls would have to wait two centuries , plus the confusing implications of James Clark Maxwell's demon. He is also famous for intertwining electricity and magnetism into a single idea. Electromagnetism, light, he discovered was nothing. Rather than a self-propagating combination of the two and written into these equations was the breakneck speed of light, but there was still a problem: what was this speed in relation to Maxwell's equations? They gave no answers, so physicists began searching for a solution, perhaps hypothesizing that light traveled. in an invisible medium, a mysterious ether that permeates the entire Cosmos, but that would also imply a final state of rest in the universe, a worrying thought since this would break Galileo's relativity, the problem was serious, so while a group Of physicists set out to measure the properties of this supposed ether others took the evidence in front of them and made an even greater leap and chief among them was a young Albert Einstein Einstein wondered why electricity and magnetism would not obey Galileo's relativity, why should they perform experiments that specifically use the flow of electricity or the spin of a The magnet revealed absolute motion in a bold step, declared that they could not, and with that the special theory of relativity was born in the Galileo's ship.

Einstein proposed that all experiments would produce the same results whether the ship was moored in harbor or gently moving out into a crystal clear sea. a ball of course wouldn't reveal if the ship was moving, but neither would measuring the speed of light, the speed of light in a vacuum was constant, this final statement seemed to go against the universe as established Newton in Newtonian mechanics. You could simply add speeds and each observer would measure different speeds depending on their own motion, but according to Einstein this was not the case for light, they would all measure the same speed whether the ship was stationary at 50 knots or 50,000, however, If this were true something else had to give and the only freedom in the equations was the very nature of space and time for it to work each observer must have their own measurement of space and each observer must have their own measurements of time with relativity special was the speed of light which was absolute, not space and time, space and time were no longer the universal stage in which physics developed and, just as Maxwell had combined electricity and magnetism, the space-time was also about to unite, gentlemen, the visions of space and time that I wish to lay before you are radical from now on.

Space alone and time alone are doomed to fade into mere shadows and only a kind of union of the two will preserve an independent reality in 1908 Hermann Minkowsky Einstein's former professor had an idea in reaction to the revelations of special relativity in 1905, he had decided to explore the geometry of these new equations in Einstein's formulation , space was space and time was time and to transform from one observer's point of view to another it was necessary to mix the two, but Minkowski pointed out We found that it was easier to mix space and time into space-time and transform space -time from one observer to another through geometry and thus finally combined space-time was born, this new fusion of the three dimensions of space and one dimension of time.

It has come to be known as Minkowski space, although Minkowski himself died tragically in 1909 before the idea of ​​it was fully adopted by the physics community. Newtonian space and time may have been completely disrupted, but Einstein still wasn't happy even though his ideas had revolutionized our ideas about the universe, they couldn't explain gravity the equations.Newton's gravitational forces needed the distance between masses, and special relativity now told us that no one could even agree on what these distances were, so Einstein went back to the drawing board and spent a decade thinking that gravity would eventually emerge.

From these reflections in 1915 a solution emerged that shocked physics to its core. Einstein had taken Minkowski's geometric image of spacetime and made both space and time flexible and elastic. The presence of mass and energy produced this curvature within this general theory. Einstein concluded that gravity. Since a force simply did not exist, the effects of gravity were encoded within the curvature of space and time. Newton's image of space and time was truly dead because not only were space and time relative, but they were also flexible. The consequences of Einstein's view of relativity were quickly discovered in special theory: the relative ticking of clocks depended on motion, and although everyone feels that time passes at a rate of one second per second, different clocks will tick different amounts of time, but with the arrival of the general theory the time was shaken even more. where you are also influences The ticking of your clock the presence of mass bends space and curves time and so gravity can dictate the relative ticking of a clock the following year in 1916 Carl Schwarzshield solved the field equations of relativity for a mass spherical and wrote inside its equations were a mass completely collapsed and compressed at one point, although it did not receive its name for 50 years.

Schwartzshield had the math for a black hole. His solution showed that black holes bend both space and time and with this intense curvature comes intense gravitation. Not even light can escape in the vicinity of a black hole where the gravitational fields are immense. Time becomes increasingly curved as you approach the center, compared to the clocks of the distant Universe near the Heart of Darkness. Time moves very slowly and it was not just black holes that emerged from new equations in the centuries after Einstein's gravitational discoveries. Many stranger solutions have been found throughout the relativistic literature; there are wormholes, warp drives, and even entire curved universes, all built from the malleable nature of space and time.

In 1919, observations of starlight bending proved his theory and made Einstein a superstar, so scientists turned their attention to measuring the effects of general relativity to further solidify the concept. One of the strangest experiments was carried out by Joseph Haffel and Richard Keating. in 1971. His equipment was a series of very precise cesium clocks and a set of jet plane trips that completely circled the Earth to begin the experiment, all the clocks were placed in the same place and some of the clocks were synchronized and Then they headed out on a plane. some heading east and others heading west, some moving with the rotation of the Earth, others against it, they spent seven thousand six hundred dollars on flights with two seats on each plane going to Mr.

Watch and because they were flying they were in a different gravitational field than The clocks that were left behind after having circled the world twice all came together. If the universe was governed by Newton's absolute time, they should all have stayed synchronized, but if Einstein was right, the relative motions and curvature of spacetime should having synchronized them, the experiment was carried out and the clocks met differed by a few hundred nanoseconds Einstein was declared the winner but there is one more test of Relativity that has proven to be the most spectacular in In the development of relativity, Einstein discovered that an elastic space-time It can also wobble and rattle, just as Maxwell founded that electricity and magnetism could wave, just like gravity, but Einstein couldn't decide if his mathematics was correct or if he was fooling himself and struggled to conclude whether these gravitational forces were correct.

The waves were part of reality in 1974 Russell Hulse was a young astronomy student who made a spectacular discovery with his supervisor Joseph Taylor while observing the universe with the 300-meter Arecibo telescope, he found a pulsar, the dead heart of a star that spins quickly. PSR b1913-16 was spinning 17 times a second and was not alone, but was orbiting another dead star, a neutron star, and with the regular heartbeats of the Pulsar they were able to accurately map the cosmic dance, what they found, however, was quite unexpected. Newtonian gravity these dead stars should orbit each other for eternity, but Taylor and Hulse discovered that the orbits were shrinking and the stars were slowly but steadily getting closer, somehow the energy from their orbits was leaking out into the universe and That's when Taylor and Hulse realized it.

Einstein's gravitational waves were an ideal culprit. They delved into the mathematics of general relativity and calculated how orbiting stars formed ripples in space-time, showing how they could precisely transport enough energy to explain the orbital disappearance in 1993. Taylor and Hulse were awarded the Nobel Prize. for his discovery and 24 years later received the award for the direct detection of gravitational waves, that experiment was the Gravitational Wave Observatory laser interferometer, or simply ligo, which with unimaginable sensitivity can sense the small ripples of space-time. ligo has opened a new and exciting window into the universe they are discovering the merger of black holes and collisions between neutron stars and now astronomers even planned to search for the oldest gravitational waves formed at the birth of the universe and so on in this new world introduced by Einstein it is clear that the entire Cosmos is written in the gravity language of curved and warped space and time, but there was one more secret to discover hidden in the equations first made by Alexander Friedman in 1922 and later proven by Edwin Hubble: The expansion of the universe is the expansion of space that expanded from a single point 13.8 billion years ago, known today as the Big Bang, in short, yesterday there was less space and tomorrow there will be more space.

It has been discovered that each galaxy moves further and further away from us according to our local system. group at an average speed of 70 kilometers per second per megaparsec, which

actually

means that right now, for every 3.26 million light years away from us, a galaxy is moving away from us at an additional 70 kilometers per second , so a galaxy 326 million light years away from us is moving at 7,000 kilometers per second and the galaxy, 32.6 billion light years away, is moving away from us faster than the speed of light. This may seem strange after everything we've learned so far, but the universe's speed limit only applies. to objects moving through space and these galaxies are not moving through space away from us, space is simply growing between us, this expanding Universe makes curving and bending spacetime even more complicated to understand, since the equations show that space is infinite, what is really happening is that the universe is becoming less dense and clearly this decrease in density is not completely uniform throughout the cosmos;

For example, individual galaxies that are also held together by their mutual gravity are not slowly drifting apart, but rather this gravity is a manifestation of the curvature of space. what happens at the boundary between expanding and non-expanding space and that is not the only problem since expanding space makes the shape of yesterday's space-time different from tomorrow's space-time, breaking So what was thought to be one of the key properties of the conservation of energy in the universe. The importance of symmetry in physics was explained in detail by the mathematician Emmy Nurtur. In this case, a symmetry means that when you change your situation, the physics remains.

Just changing location does not change the physics, which means that momentum is conserved and the fact that the physics is the same today and tomorrow gives conservation of energy, but in an expanding Universe where space-time is changing, this symmetry It breaks down as space grows, it doesn't stretch, it doesn't thin out, there's just more of it, but as the photons travel through In an expanding Universe, they stretch and lose energy and the galaxies lose their speed as they grow. its movement stops. In this way, energy is simply not conserved as the cosmos grows, a conundrum that causes problems for physicists to this day and so far as it can now appear that space has finally become real physical after all, It may bend, expand, curve and undulate, but there is one final twist, one last Rock that will be torn from beneath us and this can be summed up in the words of Nobel Prize winner Stephen Weinberg.

How is it possible for a space that is completely empty to expand? How can anything expand? The answer is that space does not expand. Cosmologists sometimes talk about expanding space, but they should know better for the beginner. This statement must seem almost strange. How can a prominent scientist do such a thing? Well, a statement because he is absolutely right about Einstein's relativity. Space-time is really nothing. Mathematics seems to bend and curve, but in reality relativity tells us that space is nothing and has no strange properties. In this new image, how were the seconds, minutes, and hours affected?

At the dawn of relativity towards future civilization, time meant many things, they knew that their time was unique, not shared by any other, they understood that clocks ticked differently depending on where you were and what you were doing. Their engineers had used this malleable nature of space. time to shape their civilization, large portals of distorted time and space allowed them to travel across the Empire, while the slow ticks near the gravitational pull of a black hole had been used to stretch time and allow them to see the end of it all. what people like us believe.

Physicists know that the distinction between past, present and future is just a stubbornly persistent illusion. With the advent of Einstein's general relativity, physicists were presented with a new headache: they knew that every particle in the universe had a past, present and future and, like a lion drawn on a map, they could trace the journey of a particle through the four dimensions of space and time, tracing its individual world line from the past to the future through a series of nows. , every particle in your body, every electron and quark travels on its own world line. Before you were conceived, the world lines were dispersed, but as you grew, many world lines condensed into one bundle that is you and when you are gone, these world lines will disperse again for a fleeting moment in time. life of the universe, you exist as little more than a collection of mundane lines a brief not in the fabric of Eternity, although disturbing, this seems to make sense, so where is the headache?

First, we must remember what the relativity of time really means, without absolute time, there is no uniform cosmic clock and this means that there is no single present, a true instant of now without an absolute definition of a cosmic now, how We define a single notion of the past? Where does the future begin? And that is why the headache within the equations of relativity, the presence of all the pasts. and the futures are already written, the complete history of all things is already somewhere. This notion known as the Block Universe has bothered many physicists and philosophers, since without a now, the cosmos simply cannot develop from one moment to the next.

All we can do is track. our world line is to follow our predefined path and the concepts we love such as free will are a lost foreigner but this cannot be right we clearly remember the past and the future is a mysterious door that has not yet been opened they are clearly different or are They consider that two electrons that are thrown towards each other have an identical negative charge and, through electromagnetism, repel each other as they approach each other, the repulsion grows and their motion gradually slows, stops and reverses , finally the electrons move away from each other where they arrived there seems like nothing.

It's strange about this, but imagine we filmed the interaction between the two electrons and then showed the film to an audience of physicists by playing a mirrored version, switching from left to right and vice versa, your audience of physicists wouldn't notice anything wrong with the film. on the screen changing. Left and right do not alterphysics, but what if you went one step further? What would happen if you were very clumsy and instead of changing from left to right you changed the past and the future? The movie now goes backwards. Time has been reversed. Your audience stares at the screen.

See in this inverted movie? Two electrons rush towards each other, getting closer and closer and their repulsion grows. They eventually stop their movement and begin to walk away again and, with nothing out of the ordinary, the audience nods approvingly, but this is simple. physics demonstration now, is this possible? If you performed the Laurel and Hardy antics in reverse, the viewers would have noticed and immediately known that something was wrong with the arrow of time and herein lies the question of why the electromagnetic interaction between electrons is insensitive to the direction of time and not only electromagnetism with gravity and the strong nuclear force are also not affected.

The weak nuclear force behaves slightly poorly, but it is a very small effect. It seems that at their core the fundamental microscopic interactions of the universe do not have an arrow of time. time could flow one way or another and they just wouldn't care this leaves us disconnected the large scale macroscopic world we inhabit certainly knows about time cooling coffee burning wood exploding supernovae these are not processes that can simply be run backwards you can't deciphering an egg, but thinking about it a little this seems strange. Clearly, our large-scale world is nothing more than the collective properties of countless numbers of atoms and these atoms interact through a fundamental force, electromagnetism, each of the countless electromagnetic interactions being unaffected. by the direction of time so how can such an arrow emerge from the multitude of time-ignorant interactions taking place every second?

How does time arise in the simple view of the block Universe? It extends infinitely into the past and infinitely into the future, but This Block Universe clearly doesn't seem to look like our own because we know that our Universe did not extend infinitely into the past. It had a beginning from observations. We know that the Universe was born almost 14 billion years ago. We don't know the time. The process that brought it into existence but was born with space and time, where and how space and time came to exist in the universe remains a mystery, but they have remained an integral part of the cosmos since its inception and There are other mysteries about The birth of the universe that we don't particularly understand, it seemed to be extremely special, being at once hot, dense and strangely soft, and this softness meant that the newborn Universe had a very particular property: the universe was born with a very low entropy, perhaps.

It seems strange that smoothness implies low entropy, since a gas spread across a room has a higher entropy than gas compressed in a corner, but for MATA in the universe this smoothness meant that gravity could do its job and fall together, eventually grouping together into stars and galaxies, and just as the universe expands, its entropy increases as matter evolves, gravitational potential energy is constantly converted into stars, planets and people, eventually this energy is processed into waste heat that spreads. throughout the Universe and it is this change from low to high entropy that imprints on the cosmos his The arrow of time The recent winner of the Nobel Prize, Sir Roger Penrose, has thought a lot about the initial entropy of our universe and has arrived at the conclusion that the probability of this happening by chance is one part in 10 to the power of 10 to the power of 123.

Clearly there must have been something special about our birth of the universe, but we still don't know what it was, and therefore would this mean that the block Universe doesn't have an innate Time Arrow without the Big Bang? Would it be impossible to distinguish the past from the future by imagining how we would experience such a universe? It is very difficult to do, but perhaps our ability to imagine anything is ultimately due to the special birth of the foreign universe. On 10 June 1944, a British Halifax bomber was flying over France with 400 other bombers supporting the D-Day landings in Normandy, but near the city of Laval, the plane was hit by a German flag and crashed in flames in the French countryside.

The entire crew died in the accident. Seven lives were lost. Seven lives in a war that ultimately claimed millions. The pilot was a 33. William Jacob van Stockham, a year-old Dutch volunteer, and although his name is not familiar today, van Stockham was the man who discovered time travel, of course in the 1930s. 1940s, time travel was a staple of science fiction. H.G Wells' The Time Machine had been published for half a century. before, but all this was fantasy and whim and a firm impossibility in Newtonian space and time, yet within the new world of relativity, Van Stockum had discovered a scientific basis.

Mathematically, relativity is notoriously challenging. Einstein himself had wondered if his field equations would produce any analytical solutions, but just a year after presenting them to the world, the first solution of this type was found. An intelligent Shield derived its black holes, so in the 1920s the search began for the mathematical form of the entire universe together with the Giants of Relativity Einstein Friedman de sitter and others established rules by finding an expanding space that a In turn it could be curved and even a space where parallel lines could converge and diverge. Some scientists explored the mathematics of hypothetical universes and the Hungarian mathematician Cornelius Lanthos had found a rather peculiar solution, his equations described the universe of dust that rotated rigidly and, Although it didn't seem to describe our actual Universe, it was an intriguing result.

Van Stockum began to wonder about the journey of particles through such a rotating universe as these particles traveled from the past to the Future. The World lines extended around the universe, but as the universe rotated, time and space stretched and distorted, some World lines extended around the universe and found themselves forming closed loops along these, the In the past, time and time again, physicists called these closed-loop world lines time-like paths, but in everyday language it was nothing less than time travel, which space and space. time could be warped enough to allow time travel was shocking and, although the rotating Universe might not be physically realistic, it opened the question of whether there were other routes to the past or shortcuts to the future.

Van Stockham's goal was to head to Princeton to work directly with Einstein, but as the clouds of war were gathering, he looked toward Europe once his homeland was occupied, his desire was to enter the fight and Van Stockholm's own world line ended up in a French field on a dark night in 1944, while van Stockholm's name is now lost to history, time travel and rotating universes are not as they were rediscovered by The El eccentric mathematician Kurt Google in 1949 Google users remember him today as one of the greatest logicians of all time and his famous incompleteness theorem still baffles today, but his contributions to physics were equally impactful as he escaped the turmoil in Europe As the storm cloud of World War II gathered unlike van stockum Google arrived at Princeton University and it was there that he and Einstein became firm friends, with Einstein supporting his application for American citizenship specifically by taking him to the hearing and distracting him from pointing out flaws in the United States Constitution to the judge hearing his case.

It was at Princeton that Google turned his remarkable mathematical mind to relativity and the nature of spacetime, and in 1949 Google's 70th birthday gift to Einstein was a solution to the field equations of relativity, as Van Stockm had found. the mathematics of a rotating universe. and closed curves similar to the time that revolved around the Cosmos of him upon receiving the gift from him. Einstein, in his own words, was concerned that Google's wife had apparently also knit him a sweater, but it was not part of the final gift. History does not record why Einstein died. shortly after, in 1955, and Google followed in 1978.

In its later years, Google asked astronomers if they had discovered that the universe was

actually

rotating, the answer was always no, it is not and that the Google universe is not ours, but there's a chance that Einstein's relativity potentially enabled time travel that sent researchers back to their equations. Foreign space really leaned in on themselves to the point of allowing temporal exploration. Physicists have continued to find mathematical shortcuts through space and time and there are now many solutions to Einstein's equations in which space and time are extremely warped, it would seem that in Einstein's relativity time travel is still a stubborn theoretical possibility, as an example, if spin is added to a black hole in space and time as well and if it plunges directly through the center, another relativist could emerge somewhere and at some time.

A wormhole constructs a space-time bridge between two places and potentially between two different times, but it is not necessarily a shortcut. The reality of these solutions remains unanswered as to whether they can really exist. We may never be able to concentrate enough energy in one place for spacetime to fold back on itself. We now understand how Einstein's spacetime works, but we still don't know what it is, where we can turn next. It wasn't just Einstein who was charting a new path at the beginning of the 20th century. century was a dramatic period for theoretical physics and quantum mechanics was at the forefront of the changing order and that is perhaps why physicists thought the answer might lie on the smallest scales of the universe in the distant future civilization had despaired.

Stars had long died and matter itself was beginning to melt, very few now remained almost frozen in darkness, the last of life stopped, but some eyes still looked towards the heavens to witness the last bursts of light in the universe that the great books had told them would happen this time. I came warning them that not even black holes would last forever as the immense gravity of Relativity held them together on the smallest scale the action of the quantum world resulted in their ultimate decay for eons they had struggled to combine the two, the world of gravity It had seemed so distant from the quantum and so far away its black hole was dissolving that they could do nothing to stop it.

The latter were so tired that they did not even try a university student who attended morning lectures on general relativity and others on Quantum mechanics in the afternoon You could be forgiven for thinking that your professors are stupid or have neglected to communicate with each other for at least a century There is a grave in Rose Lawn Cemetery in Tallahassee, Florida, written on it is the name of a man who died in 1984 82 years old. Unlike others in the cemetery, the man also has a plaque in Westminster Abbey in London, not far from Isaac Newton's remains. This plaque doesn't say much, it labels the man as a physicist and notes his birth and death, but on the plaque it is also an equation, a complex mix of Latin and Greek letters, and this equation was the first unification of Einstein's relativity and mechanics. quantum physicist Niels Bohr referred to Paul Adrian Maurice Dirac as the strangest man who visited his institute born in Bristol at the beginning of the 20th century at first he did not seem destined for scientific greatness in 1923 Dirac began his studies at the University of Cambridge focused on his science shied away from many human interactions and his conversations were mainly silent.

His colleagues even named the unit of one word per hour after Dirac in his honor, but although his speech was slow his mind revolved around the problems of physics. , it was a heady time to be a physicist with the new world of Einstein's Relativity and the strange implications of quantum mechanics. The fundamental secrets of the universe were finally revealed when Iraq began its exploration of quantum mechanics. It was written in the past. The mathematics of Schrodinger and Heisenberg were represented on Newton's stage with the ticking of an absolute clock and Galileo's vision of space. but Dirac knew that this image of space and time was simply obsolete; surely the equations of quantum mechanics should reflect Einstein's new views of space and time.

This upset Iraq and they revolted with themath trying to make it work, spending Sundays walking alone, reviewing the equations in his mind and in December 1927 the fog began to clear a relativistic quantum equation came into view an equation that obeyed Einstein's demand that there be no special rest in the universe and Iraq used this equation to explain the simplest of particles, the electron, suddenly several The peculiar properties of the electron made mathematical sense within Dirac's equation. The electron spins and behaves like a small bar magnet. Both properties had been difficult to explain, but they were a natural consequence of relativity and there was another property that was completely unexpected if you take the square. root of 1 there are two solutions plus one or minus one in the same way when explaining the electron, the Dirac equation has two solutions, one solution has a negative charge and clearly represents the electron, but what does the positive solution correspond to?

At First Direct he wondered if it could be the proton, the positively charged particle inside the nucleus, but being almost 2000 times more massive, that couldn't be correct, he finally concluded that his equation predicted a completely new particle, the antielectron, this particle It should have the same mass as the electron. but has the opposite positively charged antimatter, Dirac's equation was the birth of quantum field theory, the most successful physical theory. It is with this mathematics that scientists can describe almost all fundamental particles and forces, the basis of the modern standard model and for each of these particles there are antiparticles electrons positrons quarks and antiquarks all are a consequence of Einstein's view of relative space and the relative time, but quantum field theory is based on Einstein's special theory of relativity.

What about gravity and the general theory of relativity? Unfortunately, after such incredible initial success, the last century has not taken us any further in this quest with quantum field theory, the quantum wave function underlying existence still unfolding within the realm of space and time due to special factors. relativity this space-time is more complex than Newton's view, but space and time are still the universal stage and this stage is broken when considering the curved space-time of general relativity remember that in the general theory of relativity Space and time are dynamic and evolving. They are not simply the stage, they are actors in the physics of the universe, quantum mechanics was quite complicated, but after many years of work, its various Infinities had finally been tamed with curvatures and undulations of space-time, the Infinities seemed uncontrollable with this fails to simply merge gravity. and quantum mechanics, some physicists have looked elsewhere, this has involved going back to the drawing board with completely new ideas about what space and time are in the search for the so-called Theory of Everything, the so far fruitless search for unite the microscopic quantum world. to the macroscopic world of general relativity and completely explain the universe, but, of course, these theories of everything have not necessarily simplified things.

In one of the leading contenders, string theory or M-theory, there may be 11 or even 26 dimensions, but what do these ideas have to do with each other? I say again about the fundamental nature of time and space. It's not that simple in M ​​theory. Space and time are part of the fundamental structures of the universe. The strange twisted shape of the multi-dimensional structure explains everything, not just space and time, but all matter. radiation and all the forces, what exactly are these fundamental structures made of M? The theory doesn't tell us another contender for the theory of everything is loop quantum gravity.

At first glance, this theory is even stranger, since space and time are quantum phenomena in Space-time at the smallest possible scale is fundamentally intertwined in a network and for us this subatomic mesh has the appearance of a space and time soft, but again we can ask what these quantum grains are made of and again we are left disappointed because simply but perhaps the solution is simpler than this, perhaps some have speculated that space and time do not exist at all. Remember at the beginning of this story we heard about the disagreement between Newton and Leibnitz that Newton's space and time were part of reality and existed independently of matter in the universe Leibnitz however said that they were the relations between Mata space and time defined without them space and time would have no meaning and the relativistic view of space-time seemed to coincide with this image Einstein told us that Mata defined the structure of space-time and space-time told Mata what to do , we know that in the quantum picture space-time appears to be lumpy and reality is possibly built from these fragments of space-time as the universe grows, but what if space and time don't really exist?

What if space and time are actually emergent phenomena? Something we experience only as macroscopic beings. This may sound strange, but we know that we are trapped in the universe. This means that, for example, we do not feel the cosmological expansion that dominates the universe. universe on a large scale and similarly we don't feel the individual atoms when they collide with our skin instead we have a collective term temperature to describe what is happening maybe space and time are the same in 1997 Juan malda Cena found a relationship key in the mathematics of string theory and gravity known as the CFT correspondence of the ads, could be accidental and inconsequential, but they could also be pointing to something deeper, the path to uniting quantum mechanics and gravity, but If this is the right path, something else emerges through this relationship. space and time become granular pieces of fundamental length and fundamental time.

Planck scale pixels establishing the smallest resolution in the universe. This would mean that on the smallest scales space and time would appear as nothing more than grains of sand on a beach and therefore perhaps there is no space between the grains of reality there is no time between one grain and another. perhaps for these grains these are concepts that do not make sense, only their relationships exist, how they interact, for us, much larger than the scale of these grains, the concept of space exists and somehow through the relationships of the grains we experience the experience of experience, but underlying this may be that ultimately space and time simply do not exist and there are only fundamental bits and pieces and they are in relationships, this can be uncomfortable, where is the you in this relational universe Maybe It's best to think about it like this Most of us have accepted the fact that we are physically a collection of atoms Our Consciousness emerges Somehow we seem to be able to live with this illusion of our being Maybe all of us What we have to do is the same for the scenario in which we develop our existence and that is why we have come a long way and we are approaching the end of our journey.

The space and time. Our approach along our path seemed so natural, so normal, but we discovered it. which are much stranger and more mysterious than they appear at first glance, although Newton's space and time were simple and absolute, they became much more complex with Einstein's curvature of space-time and the quantum nature of space-time . Attempts to divide space and time into small pieces, but are we really closer to understanding their true nature? There is much hope placed in our next fundamental theories that the Theory of Everything will eventually shed light on the universal scenario and perhaps written in that theory will be the true nature of space. and time perhaps the block universe will be banished as the cosmos develops perhaps quantum processes are building one now moment at a time or perhaps some process we have yet to imagine is defining reality of course the Nature is not obliged to reveal its secrets no matter how hard Scientists work, they may never reveal the fundamental truth.

We must face the fact that some Mysteries may remain mysterious forever. In fact, what space and time really are could always be out of reach, and so we finally return to the Twilight of the cosmos within its home. the latter watched as their black hole slowly evaporated. All they wanted was to survive one more day, one more moment, but ultimately the decay of the universe could no longer be excluded. They had manipulated space. They had mastered time, but they could not defeat them. then there was Darkness, you've been watching the entire history of the universe, don't forget to like, subscribe and leave a comment to tell us what you think, thanks for watching and see you next time.