Search for the Edge of Space - 4k

[Music] the universe [Music] has long captivated us with its immense scales of distance and time [Music] in recent times giant new telescopes have allowed us to cast our gaze into the deepest reaches of the known universe [Music] astronomers have concluded that the stars and galaxies that stretch out to the limits of our vision may represent only a small fraction of all there is they are pioneering bold new theories that describe a universe that extends far beyond the limits of our vision where does it all end where do we fit within it [Music] [Music] [Music] a remote outpost in the andes mountains here astronomers are opening a whole new window onto the universe [Music] the reuben telescope with its giant state-of-the-art mirror will send a vast stream of data to a global network of processing centers and supercomputers [Music] its target [Music] dim objects racing through our solar system [Music] stars in distant galaxies exploding [Music] or flying into violent collisions these blasts of energy from distant corners of creation are messages from a universe that is evolving in ways we can scarcely comprehend they are propelling us into a new age of advanced scientific theories about the very nature of time and space theories that challenge philosophical assumptions that have guided us since ancient times [Music] the greeks were the first to see natural events as phenomena subject to human investigation rather than the whims of the gods one philosopher and sky watcher annex agaris went so far as to say that meteors are made of materials found on earth and therefore might have actually come from the earth to observers back then the world was made of four classical elements earth [Music] water air and fire the philosopher aristotle proposed that the realm of earth is fundamentally distinct from that of the stars he argued that stars are made of a fifth element unchanging and incorruptible called quintessence or space the realm of the stars in aristotle's view was the home of deities arranged in a succession of spherical regions surrounding the earth [Music] what would happen if a warrior traveled to the outermost region and tossed a spear where would it go [Music] it would not fly off on an infinite journey aristotle said rather it would join the motion of the stars in a crystalline sphere that encircled the earth he assumed the universe with earth as its focus was limited in extent finite in size aristotle grappled with an implicit challenge to this view that would one day transform science nearly two centuries before the greek mathematician pythagoras and his followers began to see numerical relationships as the key to understanding the world around them but in their investigation of geometric shapes they discovered that some important ratios could not be expressed in simple numbers one is the circumference of a circle to its diameter called pi computer scientists recently calculated pi to 5 trillion digits confirming what the greeks learned there are no repeating patterns and no ending in sight [Music] the discovery of the so-called irrational numbers like pi was so disturbing legend has it that one member of the pythagorean cult the passes was drowned at sea for divulging their existence [Music] to aristotle the idea of infinity evoked the chaos from which the world emerged a primordial state with no natural laws or limits devoid of all form and content [Music] to preserve the idea that the universe has a form and limits aristotle crafted an historic distinction on the one hand he pointed to the irrational numbers such as pi each new calculation results in an additional digit but the final final number in the string can never be reached aristotle dismissed it as potentially infinite [Music] more important in his view was a value called the actually infinite to understand it take a ruler and try calculating the number of subdivisions within subdivisions there is a final number aristotle said though we will never identify it aristotle reserved that knowledge for the so-called prime mover the one who created the universe and operates beyond our meager capacities this idea became the basis for the cosmological or first cause argument for the existence of god another century later archimedes incorporated actual infinity into measurements of curved lines and volumes his method boiled down to a process of summation place a triangle inside a circle turn it into a square then a pentagon and so on as the number of sides increases to infinity their combined lengths equal the circumference of a circle by slicing and dicing curves into an infinite number of straight lines he was able to compare a variety of curves areas and volumes archimedes anticipated techniques developed 2 000 years later and yet his ideas on infinity did not carry forward instead it was aristotle's idea of a finite universe with earth seated firmly at the center that passed into the christian era not everyone agreed islamic hindu and even some western thinkers posed alternate views that included infinite space [Music] in european circles the idea of a limited universe came into question during the renaissance in 1543 the polish astronomer nicholas copernicus argued that earth orbits the sun not the other way around the old greek spheres began to fall by the wayside when the astronomer tycho brahe spotted a supernova in 1572 then a comet these objects seem to behave independently of the other stars still church leaders frowned on any attempt to extend the boundaries of the universe for that encroached on the unique province of god that didn't stop a monk named giordano bruno who traveled europe in the height of the inquisition proclaiming an infinite universe he was burned at the stake for this and other heresies in the year 1600 nine years later in 1609 galileo galilei used the first astronomical telescope to show that the solar system and the universe are much larger than we thought galileo was forced to recant his views [Music] still the reality of a much larger cosmos had begun to sink in john milton spoke for a generation of scientists and poets in his 17th century epic paradise lost [Music] when i behold this goodly frame this world of heaven and earth consisting and compute their magnitudes this earth a spot a grain an atom [Music] at the end of the 19th century the mathematician georg cantor sought once and for all to take metaphysics out of mathematics he became known for folding finite and infinite numbers into a unified theory of number sets considered a foundation of modern math to show how it works his defenders conjured up this grand hotel [Music] you arrive to find it's booked solid but you're in luck because here there is an infinite number of rooms the manager assigns you to room number one and directs you down the corridor then she goes to work shifting the guest in room one to room two room two to room three three to four and so on so in this hotel there's a number set that includes an infinite number of rooms then there's that same set plus your room two infinite sets yet one is a subset of the other being able to use infinite sets of different sizes allowed mathematicians to design equations describing continuous motion and change over time even as mathematicians embraced infinity scientists still had trouble squaring it with physical reality albert einstein for one believed that if the universe had no limits then the night sky would be filled with dense starlight shining from every direction weed reel from the effects of infinite gravity instead much like aristotle with his warrior einstein believed that space was by its nature curved parallel lines would always meet and beams of light inevitably returned to their source as far as astronomers could see the universe had its limits it consisted of a flat disk of stars the milky way and island universe in which the solar system resides [Music] that view crumbled in the 1920s edwin hubble and milt humison used the new 100-inch telescope on mount wilson in california to look at mysterious fuzzy patches of sky called nebulae they found that some of these patches were galaxies like the milky way and very far away what's more the farther away they are the faster they are moving away from us this fact known as hubble's law led to an inescapable conclusion that the universe began at a singular moment in time a violent primordial event called the big bang [Music] this view resting on four main pillars [Music] one that the universe is expanding in all directions if you turned the clock back you'd see that everything had a common starting point two it established a time frame for the formation of stars galaxies and the distribution of matter on large scales [Music] three it established a time frame for the chemical evolution of the universe with light elements like hydrogen dominating the early universe and heavier elements generated over time in the life and death of stars [Music] finally it described the universe in its primordial state [Music] in the wake of the big bang the universe was filled with a cloud of extremely hot gas that scattered all light as the universe cooled and the first atoms formed the cloud dissipated light was able to move freely about over time as the universe expanded the spectral signature of this light would have shifted into the microwave portion of the electromagnetic spectrum in one of the great accidental discoveries of all time a pair of physicists spotted this primordial light back in the 1960s bell labs had built a giant horn-shaped antenna as part of a long-distance radio transmission system [Music] arno penzias and robert wilson pointed this contraption into space [Music] wherever they aimed they picked up excessive microwave noise [Music] that noise part of the static on many old style televisions is the echo of the big bang decades later the hubble space telescope launched into orbit on april 24th 1990 in one of the most important scientific milestones of our time another notable launch took place five months earlier the cosmic observation background explorer kobe for short it found that the microwave background signal in space contains a subtle pattern of hot and cold spots [Music] later missions mapped an even more detailed pattern including this image from the european planck observatory if scientists can find the source of this pattern they might learn not only about how the universe began but where it's going at the european large hadron collider they are sending protons racing in opposite directions in a circular tunnel 27 kilometers long when these particles reach velocities just short of the speed of light they are sent into a violent collision a fireball erupts reaching a temperature exceeding 2 trillion degrees centigrade as far as we know the last time anything in our universe was that hot was about a millionth of a second after its birth the splatter of subatomic particles forms a super hot soup of corks and gluons the thinking is that a primordial energy field that spawned the big bang was patterned with tiny fluctuations these fluctuations generated pressure waves or ripples that passed through the ultra dense cork gluon mix as the universe expanded these ripples would have been imprinted on the distribution of matter on the largest of scales to test this idea astronomers set out to literally map the universe in three dimensions in an age of computer-controlled telescopes and automated observing astronomers targeted a large fraction of the sky the sloan digital sky survey in the mountains of new mexico set the standard for large-scale cosmic cartography a series of steel plates are drilled with holes that exactly match the locations of galaxies in the night sky after plugging fiber optic sensors into the holes the plates are loaded into the telescope it then captures the light of hundreds of galaxies per night gathering information about their brightness and distance from earth from this data astronomers are assembling a whole new cosmic atlas in three dimensions [Music] traveling out into the data we pass beyond our remote corner of the milky way we enter a collection of 20 odd galaxies known as the local group our cosmic neighborhood [Music] our path takes us some 50 million light years away to the densely packed virgo supercluster the nearest intergalactic city [Music] beyond virgo galaxies line up in walls and arcs bounded by vast empty voids the goal in ever larger survey projects is to trace the evolution of these structures all the way back to their beginnings looking north the sloan digital sky survey has mapped galaxies out to one-third the distance to our visible horizon astronomers are now leaping beyond that with projects based in the mountains of chile [Music] the dark energy survey uses one of the largest cameras in the world to divide the field of view into 62 high resolution detectors each one captures countless thousands of celestial objects extending halfway across the visible universe night after night month after month the exposures pile up across a survey area that covers a quarter of the southern sky or an eighth of the entire sky as seen from earth the reuben telescope on a nearby mountain expands that to one half the sky seen from earth how far we can see into the deep universe is determined by the speed of light how far the light of distant objects would have traveled since the big bang [Music] using hubble and other modern telescopes astronomers have placed that time at 13.7 billion years ago taking into account the expansion of space ever since the radius of the visible universe our visible horizon extends out to 46 billion light years from earth if you look in opposite directions the most distant galaxies discovered by the hubble space telescope are actually 92 billion light years from each other the horizons of those galaxies would stretch to 138 billion light years from earth where does it end [Music] in fact our 92 billion light year wide patch the visible universe may be a mere speck within the universe as a whole that's the conclusion of a dramatic new theory designed to address questions about the nature of the big bang one how did the universe get so large so quickly [Music] and two how did it get so smooth in every direction you look the density of galaxies is the same on large scales whatever process flung the universe outward must have somehow blended it in its earliest moments the new theory called inflation is based on the discovery that space is not as scientists once thought just the absence of matter [Music] it is actually seething with energy in the form of particles of opposite charge matter and antimatter [Music] back in the 1980s the physicist alan guth proposed that in primordial times an energy field embedded in the vacuum of space suddenly tipped into a higher energy state causing space and time to literally inflate and our universe to burst forth [Music] the universe went from atomic size to cosmological size within an infinitesimally short time as a result according to guth's calculation the universe as a whole would have grown to some 10 billion trillion times the size of the observable universe that's a 10 followed by 24 zeros [Music] put another way an atom is to the observable universe as the observable universe is to the whole universe [Music] [Music] the fury of cosmic inflation helps explain the immense size and smoothness of the cosmos but this basic theory still does not get us beyond the idea held by thinkers from aristotle to einstein that the universe is closed finite in size even if mind-bogglingly large recent versions of inflationary theory have begun to force concepts of infinity back into our popular cosmology [Music] astronomers have known for decades that the amount of matter observed in distant galaxies does not supply enough gravity to hold these spinning structures together there is a missing ingredient that we just do not see its identity still unknown scientists call it dark matter by adding dark matter into supercomputer simulations of cosmic evolution scientists have been able to recreate the gravitational fields needed to form the large scale structures we observe [Music] astronomers wanted to know is the gravity of dark matter enough to one day slow the cosmic expansion to a stop to answer this question they sought to refine their measurements of cosmic expansion by using a new type of distance marker called a type 1a supernova [Music] it emerges from the charred remains of a sun-like star called a white dwarf if this star takes on mass by drawing it from another star it may grow to a critical threshold and explode [Music] type 1a supernovae are thought to shine at uniform intensities throughout the universe so if astronomers measure differences in their brightness at varying distances that could indicate a change in the cosmic expansion rate over time to their surprise the data showed that the universe as a whole is not only expanding it's actually accelerating outward the culprit is thought to be energy welling up in minute quantities from the vacuum of space as the universe expands the force exerted by these particles increases over time enough to push space outward across the whole universe this so-called dark energy now amounts to an astonishing three-fourths of all the matter and energy in the universe if it's similar to what drove inflation in the early moments of the big bang then our universe may exist in a far broader cosmic context than we've imagined there is a version of inflationary theory that suggests we live in one of many universes that emerged and coexist side by side like bubbles continually rising up from an infinitely vast quantum vacuum are expanding throughout an endless ocean of space and time a related idea theorizes a cosmic landscape unfolding in vast fractal patterns from this new perspective our universe however we define it is incomprehensibly small as if that's not mind-boggling enough yet another version of inflation appends our entire conception of time and space astronomers at the rubin and other observatories will be scanning the heavens for a breed of black holes that would have been born moments after the universe burst forth some might have sown the seeds of the first galaxies growing over time to millions even billions of times the mass of the sun others far more numerous and as small as the moon were left to roam the cosmos moving silently amid the luminous dust lanes and glowing stars of galaxies like ours the idea is to scan billions of stars in the milky way and other galaxies if a black hole passes through our line of sight a star behind it will dim then brighten the discovery of these objects would lend insight into one of inflation's wilder predictions that in the ultra dense conditions of early times more than one universe would have inflated perhaps within one of those primordial black holes from our vantage point on the outside these objects would appear simply as black holes if you could go inside a baby universe would appear to be expanding outward much like our own [Music] in galileo's time most sky watchers saw the universe as an assemblage of stars that surrounded the earth in relatively close proximity he showed instead that stars are far removed from our planet imagine how galileo would have reacted to this image of earth captured in the year 1979 by the spacecraft voyager 2 as it passed by neptune [Music] since galileo's time our earth has gone from the center of all things to a pale blue dot lost in the vastness of space we now know it is set within a universe of galaxies clusters of [Music] galaxies and beyond them vast luminous walls and filaments of matter [Music] today's ideas about the size of the universe amount to a quantum leap in our sense of scale [Music] by extending these structures far far beyond our horizon perhaps touching on the infinite [Music] [Music] do our discoveries push us on this tiny out of the way planet into an ever smaller corner of creation [Music] or does our ability to comprehend and imagine the far limits of time and space somehow expand our importance in the grand scheme of things [Music] [Music] [Music] foreign [Music] you

Channel: SpaceRip

Views: 911,589

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Id: k0Wiealif5U

Length: 42min 33sec (2553 seconds)

Published: Mon Apr 25 2022