NASA
The Andromeda Galaxy, seen at ultraviolet wavelengths. This mosaic covers a region 200,000 light-years wide and is made up of 330 individual images taken by NASA's Swift satellite.
The State Of The Universe Address
by Marcelo Gleiser
I would like to start by thanking those members of the human race who, through their inventiveness and diligence, have learned so much about my properties over the past few millennia. In this address I will, for the sake of clarity, adopt the human notion of time, which is indeed very practical, although somewhat quaint. Those other intelligences spread around my domain should pay attention to what these humans are doing.
I continue to expand, as I have for the past 13.7 billion years. Things were quite lonely, I must say, for most of this time. Deep silence, no minds tinkering with the mysteries that I ingeniously create to entertain myself over the eons. Yes, for within the initial furnace that followed the big bang, my birth so to speak, particles of matter and radiation simply zoomed around with no chance of forming anything very stable. I was filled in those days with a hot soup of primordial matter and radiation — nothing more.
Only after some four-hundred-thousand years the first atoms appeared. And even so, only the simplest of them were present, what humans call hydrogen and helium. It’s true that I am partial to humans. There are many brute forms of life across my volume, some quite curious to behold. However, in humans I find that spark of magic that makes all the difference, an appreciation for things that transcend them. While most life forms simply live, humans aspire to more than that. They have concepts such as dignity, respect and love that I find quite creative. Perhaps that’s the reason why while all other intelligent life forms self-destruct after they reach a certain level of technological prowess, humans have managed to remain alive, even if currently struggling.
Those first atoms of hydrogen, through the workings of gravity, managed to coalesce into highly dense spherical blobs called stars. In their cores, when temperatures reach some 15 million degrees, hydrogen fuses into helium, the second most complex chemical element. This is the transmutation that holds the key to all complexity within my volume. Yes, nothing is more important than this fusion. From it, stars ignite and produce the light and energy that will warm up their court of planets and moons; from it, life extracts its energy; from it, when these stars approach the end of their lives, heavier atoms are formed, sprinkling the interstellar space with the ingredients that make life possible throughout. This is my dance of creation and destruction, the true harmony of the worlds: dying stars giving birth to new ones and to the ingredients that make life possible.
These clever humans have figured all this out in only a few hundred years. They have even realized that my expansion is variable, sometimes faster sometimes slower, depending on what kinds of matter and radiation are more important. They know that for the past few billion years I’ve been going through a period of accelerated expansion, that the distances between galaxies is increasing quite fast. I loved to see the look of total surprise in the faces of some of the human scientists when they found this out. Hopefully, they are finally learning that we things cosmic it’s best to keep their minds open, and to have the humility to accept that no view of mine that they acquire will ever be complete. The more they probe into my mysteries the more surprises they will find. That amuses me greatly and surely keeps them busy. I hope those other brutes across my domain, who spend so much of their times fighting and killing each other for pathetic reasons, will learn that lesson, and learn to engage themselves in the pursuit of knowledge.
I know I was quite partial when I allowed Earth to form 4.6 billion years ago. Yes, it’s an unusual world, very special. For among the trillions of worlds out there, very few bear the properties of this small blue jewel of mine. I am intrigued by how slow humans have been in realizing the importance of their world. Especially now that they have the means to study other worlds in some detail, they should be praising their gods (well, me really) for their luck. Had things been only slightly different, they’d have a lot of trouble surviving there. Do they realize this? I’m not sure, at least judging from the disappearing of green over the Earth’s surface. Whatever they are doing there, it’s on a global scale. Interesting for me to see that a single species can evolve to affect the whole planet willingly and when it does so, it seems to act destructively. I guess it’s hard for them to strike a balance between their need to survive and their planet’s need to replenish its resources. Hopefully they will learn faster than the others. I’m tired of looking at desert worlds across my domain, worlds that once were as alive as Earth is now.
Let’s start with our universe.
What an amazing place to be alive! Some 200 billion galaxies, each with some 200 billion stars, a good fraction of them with planets, and these planets with moons. Trillions of worlds besides our own, each unique, each with its own history, with its own mysteries and wonders.
If Copernicus thought (he didn’t, but many who followed him did) that displacing the Earth from the center of the cosmos would make the cosmos and the Earth less interesting, he was quite wrong. This expanding fabric of space, with texture so rich we couldn’t have imagined even 20 years ago, will never cease to amaze us.
What’s beyond space? What happened before the big bang, the event that kick-started time? These are the questions so many want to understand. Can we? Yes, we can!
Our present measurements — and remember, all we can say about the world is what we can measure of it; the rest may be cool to talk about in parties but it’s speculation until measured — indicate that space is flat: this means that it goes on forever.
Now, do we know that for sure? Not really. All we can say is that the portion of space that we can measure, that is, the portion that is delimited by the distance light traveled since the initial bang 13.7 billion years ago, is flat or very very nearly so. Think of a beach and the horizon in the distance. You know the ocean doesn’t end there, just what you can see of it. Well, it's the same with space. We can see as far as light traveled since the beginning of time, a staggering 45 billion lightyears, in round numbers. Beyond that there is more space, and probably more galaxies, more stars, more planets. (Why 45 billion lightyears and not 13.7? Because light gets a “push” from the cosmic expansion as a surfer riding on a wave and covers a larger distance than only 13.7 billion light-years.)
How can we be so certain?
Because our measurements tell us that the laws of physics and chemistry are the same across the vastness of space. How mind-boggling is that? We can tell what a star is made of without ever needing to go there; we can tell how galaxies formed some 10 billion years ago, way before Earth even existed. As we look into space we look into the past: the farther away, the farther into the beginning. Who said there is no magic in science?
And what about “the” beginning? Well, we don’t really know. But we do know a lot of the cosmic history all the way down to one trillionth of a second after the big bang. Not too bad for a science that is only about 400 years old, right? We also know that there isn’t much sense in asking what happened before the big bang. Kind of asking who were you before you were born. Since there was no time ticking for you, there was no you. As Saint Augustine cleverly said some 16 centuries ago, space and time came into being with the cosmos. No cosmos, no space and no time.
If only it were so simple.
Some speculate that our Universe is just a chunk of a much larger (how large?) entity, a multiverse that represents all possible realizations of universes. Or almost all. In each of them, the laws of nature may be different, and most would blatantly fail to become anything interesting. As in no life.
So, give thanks to our universe, the one among the many that has the right properties to live long enough so that galaxies and stars can form, and then planets and, in some of them, life.
But wait! Don’t get carried away. Our universe couldn’t care less about life or about preserving it. Be suspicious of arguments that claim that our universe is just right for life!
Just look at our cosmic neighbors, barren worlds, desolate and fascinating. Strip away our thin atmosphere, our protective magnetic and ozone shields and Earth would turn barren too, a dead world incapable of harboring life. (Or at least complex life. Maybe simple life is resilient enough to survive in very extreme conditions.)
So, it’s not really to the universe that we should be giving thanks but to Earth itself, our amazing, life-bearing, life-preserving planet. The more we move outwards to explore other worlds, the more remarkable our own becomes. We should all, collectively as a species, be giving thanks to our world. Most of all, for its patience in taking so much abuse from us and still letting us stick around. Few mothers would be this patient.
I would like to start by thanking those members of the human race who, through their inventiveness and diligence, have learned so much about my properties over the past few millennia. In this address I will, for the sake of clarity, adopt the human notion of time, which is indeed very practical, although somewhat quaint. Those other intelligences spread around my domain should pay attention to what these humans are doing.
I continue to expand, as I have for the past 13.7 billion years. Things were quite lonely, I must say, for most of this time. Deep silence, no minds tinkering with the mysteries that I ingeniously create to entertain myself over the eons. Yes, for within the initial furnace that followed the big bang, my birth so to speak, particles of matter and radiation simply zoomed around with no chance of forming anything very stable. I was filled in those days with a hot soup of primordial matter and radiation — nothing more.
Only after some four-hundred-thousand years the first atoms appeared. And even so, only the simplest of them were present, what humans call hydrogen and helium. It’s true that I am partial to humans. There are many brute forms of life across my volume, some quite curious to behold. However, in humans I find that spark of magic that makes all the difference, an appreciation for things that transcend them. While most life forms simply live, humans aspire to more than that. They have concepts such as dignity, respect and love that I find quite creative. Perhaps that’s the reason why while all other intelligent life forms self-destruct after they reach a certain level of technological prowess, humans have managed to remain alive, even if currently struggling.
Those first atoms of hydrogen, through the workings of gravity, managed to coalesce into highly dense spherical blobs called stars. In their cores, when temperatures reach some 15 million degrees, hydrogen fuses into helium, the second most complex chemical element. This is the transmutation that holds the key to all complexity within my volume. Yes, nothing is more important than this fusion. From it, stars ignite and produce the light and energy that will warm up their court of planets and moons; from it, life extracts its energy; from it, when these stars approach the end of their lives, heavier atoms are formed, sprinkling the interstellar space with the ingredients that make life possible throughout. This is my dance of creation and destruction, the true harmony of the worlds: dying stars giving birth to new ones and to the ingredients that make life possible.
These clever humans have figured all this out in only a few hundred years. They have even realized that my expansion is variable, sometimes faster sometimes slower, depending on what kinds of matter and radiation are more important. They know that for the past few billion years I’ve been going through a period of accelerated expansion, that the distances between galaxies is increasing quite fast. I loved to see the look of total surprise in the faces of some of the human scientists when they found this out. Hopefully, they are finally learning that we things cosmic it’s best to keep their minds open, and to have the humility to accept that no view of mine that they acquire will ever be complete. The more they probe into my mysteries the more surprises they will find. That amuses me greatly and surely keeps them busy. I hope those other brutes across my domain, who spend so much of their times fighting and killing each other for pathetic reasons, will learn that lesson, and learn to engage themselves in the pursuit of knowledge.
I know I was quite partial when I allowed Earth to form 4.6 billion years ago. Yes, it’s an unusual world, very special. For among the trillions of worlds out there, very few bear the properties of this small blue jewel of mine. I am intrigued by how slow humans have been in realizing the importance of their world. Especially now that they have the means to study other worlds in some detail, they should be praising their gods (well, me really) for their luck. Had things been only slightly different, they’d have a lot of trouble surviving there. Do they realize this? I’m not sure, at least judging from the disappearing of green over the Earth’s surface. Whatever they are doing there, it’s on a global scale. Interesting for me to see that a single species can evolve to affect the whole planet willingly and when it does so, it seems to act destructively. I guess it’s hard for them to strike a balance between their need to survive and their planet’s need to replenish its resources. Hopefully they will learn faster than the others. I’m tired of looking at desert worlds across my domain, worlds that once were as alive as Earth is now.
Let’s start with our universe.
What an amazing place to be alive! Some 200 billion galaxies, each with some 200 billion stars, a good fraction of them with planets, and these planets with moons. Trillions of worlds besides our own, each unique, each with its own history, with its own mysteries and wonders.
If Copernicus thought (he didn’t, but many who followed him did) that displacing the Earth from the center of the cosmos would make the cosmos and the Earth less interesting, he was quite wrong. This expanding fabric of space, with texture so rich we couldn’t have imagined even 20 years ago, will never cease to amaze us.
What’s beyond space? What happened before the big bang, the event that kick-started time? These are the questions so many want to understand. Can we? Yes, we can!
Our present measurements — and remember, all we can say about the world is what we can measure of it; the rest may be cool to talk about in parties but it’s speculation until measured — indicate that space is flat: this means that it goes on forever.
Now, do we know that for sure? Not really. All we can say is that the portion of space that we can measure, that is, the portion that is delimited by the distance light traveled since the initial bang 13.7 billion years ago, is flat or very very nearly so. Think of a beach and the horizon in the distance. You know the ocean doesn’t end there, just what you can see of it. Well, it's the same with space. We can see as far as light traveled since the beginning of time, a staggering 45 billion lightyears, in round numbers. Beyond that there is more space, and probably more galaxies, more stars, more planets. (Why 45 billion lightyears and not 13.7? Because light gets a “push” from the cosmic expansion as a surfer riding on a wave and covers a larger distance than only 13.7 billion light-years.)
How can we be so certain?
Because our measurements tell us that the laws of physics and chemistry are the same across the vastness of space. How mind-boggling is that? We can tell what a star is made of without ever needing to go there; we can tell how galaxies formed some 10 billion years ago, way before Earth even existed. As we look into space we look into the past: the farther away, the farther into the beginning. Who said there is no magic in science?
And what about “the” beginning? Well, we don’t really know. But we do know a lot of the cosmic history all the way down to one trillionth of a second after the big bang. Not too bad for a science that is only about 400 years old, right? We also know that there isn’t much sense in asking what happened before the big bang. Kind of asking who were you before you were born. Since there was no time ticking for you, there was no you. As Saint Augustine cleverly said some 16 centuries ago, space and time came into being with the cosmos. No cosmos, no space and no time.
If only it were so simple.
Some speculate that our Universe is just a chunk of a much larger (how large?) entity, a multiverse that represents all possible realizations of universes. Or almost all. In each of them, the laws of nature may be different, and most would blatantly fail to become anything interesting. As in no life.
So, give thanks to our universe, the one among the many that has the right properties to live long enough so that galaxies and stars can form, and then planets and, in some of them, life.
But wait! Don’t get carried away. Our universe couldn’t care less about life or about preserving it. Be suspicious of arguments that claim that our universe is just right for life!
Just look at our cosmic neighbors, barren worlds, desolate and fascinating. Strip away our thin atmosphere, our protective magnetic and ozone shields and Earth would turn barren too, a dead world incapable of harboring life. (Or at least complex life. Maybe simple life is resilient enough to survive in very extreme conditions.)
So, it’s not really to the universe that we should be giving thanks but to Earth itself, our amazing, life-bearing, life-preserving planet. The more we move outwards to explore other worlds, the more remarkable our own becomes. We should all, collectively as a species, be giving thanks to our world. Most of all, for its patience in taking so much abuse from us and still letting us stick around. Few mothers would be this patient.
>>>
Will humans figure out what is fueling my fast expansion?
I love the name they gave to it, “dark energy,” as quaint as their notion of time. I hope they won’t get carried away by giving it a name and attribute to it properties it doesn’t have. They did this with space and time, these two inventions to describe distance and change. They need concepts to organize their thoughts, certainly. But to make those concepts into real things can be confusing. As when they say that space is expanding or time is ticking away and take these things literally. Nah, these are just ways to organize measurements, nothing that exists on its own. But I have confidence they will see all of this in due time. When they figure out why I’m expanding fast now and what is this thing they call dark energy, some of these mysteries will be cleared up. Only, of course, to give rise to new ones. Meanwhile, I’ll keep expanding, creating and destroying worlds, to my great enjoyment and, of course, to that of humans. After all, let me be frank. Even I am an invention of their minds. We are all in this together.
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