Sethians

4:53 AM | BY ZeroDivide EDIT
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The Sethians were a Gnostic sect during the Roman era. Alongside Valentinianism, Sethianism was one of the main currents of Gnosticism during the 2nd to 3rd centuries. Their thinking, though it is predominantly Judaic in foundation, is arguably strongly influenced by Platonism. Sethianism attributed its gnosis to Seth, third son of Adam and Eve and Norea, wife of Noah (who also plays a role in Mandeanism and Manicheanism).

Mentions of the Sethians[edit]

The Sethians (Latin Sethoitae) are first mentioned, alongside the Ophites, in the 2nd century, by Irenaeus and in Pseudo-Tertullian (Ch.30).[1][2]
According to Frederik Wisse (1981)[3] all subsequent accounts appear to be largely dependent on Irenaeus.[4] Hippolytus repeats information from Irenaeus. According to Epiphanius of Salamis (c.375) Sethians were in his time found only in Egypt and Palestine, although fifty years before they had been found as far away as Greater Armenia (Panarion 39.1.1 2; 40.1).[5] One of the sources of Epiphanius, the lost Syntagma of Hippolytus of Rome, was also the source for Christian heresies before Noetus in Philaster's Catalogue of heresies. Nathaniel Lardner (1838) noted that Philaster places theOphites, Cainites, and Sethians as pre-Christian Jewish sects.[6] However, since Sethians identified Seth with Christ (Second Logos of the Great Seth), Philaster's belief that the Sethians had pre-Christian origins, other than in syncreticabsorption of Jewish and Greek pre-Christian sources, has been not found acceptance in later scholarship.[7]

Sethian texts[edit]

Most surviving Sethian texts are preserved only in Coptic translation of the Greek original. Very little direct evidence of Gnostic teaching was available prior to the discovery of the Nag Hammadi library, a collection of 4th-century Coptic translations of Gnostic texts which were apparently hidden in reaction to Athanasius of Alexandria's Easter letter of 367 which banned the use of non-canonical books. Some of these texts are known to have been in existence in the 2nd century, but it is impossible to exclude the presence of later syncretic material in their 4th-century translations.

Teachings[edit]

Commonly, the Sethian cosmogonic myth describes an intended prologue to the events of Genesis and the rest of the Pentateuch, which by its emendation brings about a radical reinterpretation of the typical orthodox Jewish conception of creation, and the divine's relation to reality. This myth is typically presupposed by Sethian manuscripts, and occasionally by those of later schools. Many of their concepts derived from a fusion of Platonic or Neoplatonic concepts with the Old Testament, as was common in Hellenistic Judaism, exemplified by Philo (20 BC - 40 AD).
The Sethian cosmogony was most famously contained in the Apocryphon of John, which describes an Unknown God, the same as Paul had done in the Acts of the Apostles 17:23. While one conception defines God through a series of explicit positive statements called cataphatic theology, themselves universal but in the divine taken to their superlative degrees: as well as being explicitly male, he is omniscient and omnipotent. The Sethian conception of God is, by contrast, defined through negative theology exclusively: he is immovable, invisible, intangible, ineffable. This Apophatic Theology (Negative theology) mode of thinking about God is found throughout Gnosticism and also has precedents in some Judaic sources (for example, the theology of Maimonides[clarification needed]).

The emanation of the spiritual universe[edit]

The original "Unknown God" went through a series of emanations, during which its essence is seen as spontaneously expanding into many successive 'generations' of paired male and female beings, called 'aeons'. The first of these is Barbelo, a figure common throughout Sethianism, who is coactor in the emanations that follow. The aeons that result can be seen as representative of the various attributes of God, themselves indiscernible when not abstracted from their origin. In this sense, Barbelo and the emanations may be seen as poetic devices allowing an otherwise utterly unknowable God to be discussed in a meaningful way amongst initiates. Collectively, God and the aeons comprise the sum total of the spiritual universe, known as the Pleroma.
At this point the myth is still only dealing with a spiritual, non-material universe. In some versions of the myth, the Spiritual Aeon Sophia imitates God's actions in performing an emanation of her own, without the prior approval of the other aeons in the Pleroma. This results in a crisis within the Pleroma, leading to the appearance of the Yaldabaoth, a 'serpent with a lion's head'. This figure is commonly known as the demiurge, after the figure in Plato's Timaeus. (Gr. δημιουργός dēmiourgós, Latinized demiurgus, meaning "artisan" or "craftsman")[8] This being is at first hidden by Sophia but subsequently escapes, stealing a portion of divine power from her in the process.

The creation of matter[edit]

Using this stolen power, Yaldabaoth creates a material world in imitation of the divine Pleroma. To complete this task, he spawns a group of entities known collectively as Archons, 'petty rulers' and craftsmen of the physical world. Like him, they are commonly depicted as theriomorphic, having the heads of animals. Some texts explicitly identify the Archons with the fallen angels described in the Enoch tradition in Judaic apocrypha. At this point the events of the Sethian narrative begin to cohere with the events of Genesis, with the demiurge and his archontic cohorts fulfilling the role of the creator. As in Genesis, the demiurge declares himself to be the only god, and that none exist superior to him; however, the audience's knowledge of what has gone before casts this statement, and the nature of the creator itself, in a radically different light.
The demiurge creates Adam, during the process unwittingly transferring the portion of power stolen from Sophia into the first physical human body. He then creates Eve from Adam's rib, in an attempt to isolate and regain the power he has lost. By way of this he attempts to rape Eve who now contains Sophia's divine power; several texts depict him as failing when Sophia's spirit transplants itself into the Tree of Knowledge; thereafter, the pair are 'tempted' by the serpent, and eat of the forbidden fruit, thereby once more regaining the power that the demiurge had stolen.
As is evident, the addition of the prologue radically alters the significance of events in Eden; rather than emphasizing a fall of human weakness in breaking God's command, Sethians (and their inheritors) emphasize a crisis of the Divine Fullness as it encounters the ignorance of matter, as depicted in stories about Sophia. Adam and Eve's removal from the Archon's paradise is seen as a step towards freedom from the Archons, and the serpent in the Garden of Eden in some cases becomes a heroic, salvific figure rather than an adversary of humanity or a 'proto-Satan'. Eating the fruit of Knowledge is the first act of human salvation from cruel, oppressive powers.

Summary of the Text and its Cosmology[edit]

There are currently four surviving copies of The Secret Revelation of John. They are largely the same in their basic structure and content. One notable difference between the codices is their individual length. The Berlin Codex and Nag Hammadi Codex III are shorter than the Nag Hammadi Codices I and II. One point of departure between codices is the portrayal of the Savior/Christ figure. The Berlin Codex generally uses the term “Christ” more frequently, whereas the Nag Hammadi Codex III narrative often substitutes the term “Lord” or “Savior”. However, the Nag Hammadi Codex III closes its text with the prayer “Jesus Christ, Amen.” An additional distinction, with regards to the Christian framing of the texts, is that Nag Hammadi Codex III goes into greater detail about the descent of the Christ/Savior figure into the prison-world of Demiurge and his role in facilitating the reawakening and liberation of mankind. These distinctions may represent a certain degree of variation in the way that Gnostic cosmology was woven into a Christian context.
The below summary of the Apocryphon is derived from Wisse’s translation.
The text begins with John describing his own state of grief and bewilderment after Christ’s crucifixion. The Savior then appears, takes various forms, and after banishing John’s fears, provides the following cosmological narrative.
The highest divine principle is the Monad. The Monad is described as a “monarchy with nothing above it”. He is supreme, absolute, eternal, infinite, perfect, holy and self-sufficient. However, his transcendent ineffability is also emphasized. He is neither quantifiable nor can his qualities ever truly be described. The Monad exists in inconceivable perfection.
The Monad produces from his thought a feminine divine entity or principle named Barbelo. She is described as “the first thought”, and the “image” of the Monad. While Barbelo is always referred to as a ‘she’, she is also described as both the primordial mother and father. She is also regarded as “the first man” and described in various terms of androgyny. She is the first of a class of beings referred to as the Aeons, and an exchange between herself and the Monad brings the other Aeons into being. Additionally, the properties of Light and Mind are born from the Monad’s reflection on Barbelo. Light is synonymous with Christ, also called “Christ the Autogenes”. The Light and the Mind engage in further creative activity, aided by and glorifying the superior principles of Barbelo and the Monad. Together, they bring forth further Aeons and powers.
Eventually, one of the Aeons, Sophia “of the Epinoia”, disrupts the harmony of these processes by engaging in creative activity without the participation or consent of the Spirit of the Monad and without the aid of a male consort. The creative power of her thought produces an entity named Yaltabaoth, who is the first of a series of incomplete, demonic entities called the Archons. Yaltabaoth, whose character is malevolent and arrogant, also has a grotesque form. His head is that of a lion while he possesses a serpentine body. Recognizing the deformed, imperfect nature of her offspring, Sophia attempts to conceal it somewhere where the other Aeons will not discover it. The act of hiding Yaltabaoth also has the result that Yaltabaoth himself remains ignorant of the upper world and the other Aeons.
Despite the fact that Yaltabaoth possesses only a single parent and was created without the consent of the Spirit of the Monad, he is powerful enough to mimic the creative processes of the superior Aeons. He creates a whole host of other Archons, each of whom share his own basically deficient character, and creates a world for them to inhabit. This world is fundamentally inferior to the world above. It is fashioned out of darkness, but animated by light stolen from Sophia. The result is a world that is neither “light nor dark” but is instead “dim”. In his arrogance and ignorance, Yaltabaoth declares himself the sole and jealous God of this realm. Recognizing the imperfection of Yaltabaoth and his counterfeit world, Sophia repents. In forgiveness of her error, the Spirit of the Monad assists the other Aeons and powers in an attempt to redeem Sophia and her bastard creation. During this process Yaltabaoth and his angels hear the voice of the Monad’s Spirit. While they are terrified by the voice, its echo leaves a trace of an image of the Spirit on the “waters” that form the roof of their realm. Hoping to harness this power for themselves, they attempt to create a copy of this image. The end result of this process is the first human man, Adam. Recognizing an opportunity to retrieve the light imprisoned in the darkness of Yaltabaoth and his world, Sophia and agents of the higher order, referred to variously as the ‘plenoria’ or the ‘Epinoia’, and later as the ‘pleroma’, devise a scheme. They trick Yaltabaoth into blowing his own spiritual essence into Adam. This simultaneously animates Adam and empties Yaltabaoth of the portion of his being derived from Sophia.
Seeing the luminosity, intelligence and general superiority of the now animate Adam, Yaltabaoth and the Archons regret their creation and do their best to imprison or dispose of him. Failing to do so, they then attempt to neutralize him by placing him in the Garden of Eden. In this narrative, the Garden of Eden is a false paradise where the fruit of the trees is sin, lust, ignorance, confinement and death. While they give Adam access to the tree of Life, they conceal the Tree of Knowledge of Good and Evil. According to this narrative, the Tree actually represents the penetration of the positive forces of the higher world and the Epinoia into Yaltabaoth’s realm.
At this point in the narrative, Christ reveals to John that it was he who caused Adam to consume the fruit of the Tree of Knowledge. Additionally, it is revealed that Eve is a helper sent by agents of the higher order to help liberate the light imprisoned in Yaltabaoth’s creation and in Adam. She is created when Yaltabaoth attempts to draw the light out of Adam. This results in the creation of the female body. When Adam perceives her, he sees a reflection of his own essence and is freed from the bewitching power of Yaltabaoth.
The narrative then details Yaltabaoth’s attempts to regain control over the essence of Light. His primary scheme is to initiate the activity of human reproduction, by which he hopes to create new human bodies inhabited by a counterfeit spirit. This counterfeit spirit allows Yaltabaoth and his agents to deceive the human race, keeping them in ignorance of their true nature, and is the primary means by which Yaltabaoth keeps humanity in subjugation. It is the source of all earthly evil and confusion, and causes people to die “not having found truth and without knowing the God of truth”. Following this revelation, the narrative then takes the form of a series of questions and answers between John and the Savior. These address a number of subjects, but are largely soteriological in nature. John asks Christ whom is eligible for salvation, and Christ responds with the answer that those who come in contact with the true Spirit will receive salvation, while those who are dominated by the counterfeit spirit will receive damnation. Christ also reveals his own role as a liberating agent of the higher realm, in this context. Christ, who describes himself as the “remembrance of the Pronoia” and “the remembrance of the pleroma”, brings light into the darkness of Yaltabaoth’s prison. Here, he rouses the prisoners to wakefulness and remembrance. Those who receive and are woken by Christ’s revelation are raised up and “sealed… in the light of the water with five seals”. They are thus spared from death and damnation. This aspect of Christ’s role is elaborated on more fully by Nag Hammadi Codex III, whereas it is omitted from the Berlin Codex.
This concludes Christ’s message. Finally, the savior states that anyone who shares these revelations for personal profit will be cursed. The Nag Hammadi Codex III version of the text ends with the prayer, “Jesus Christ, Amen”.

Once upon a time, people actually got paid to lend money.

4:44 AM | BY ZeroDivide EDIT
Once upon a time, people actually got paid to lend money.
It was something that early humans called "interest." The way it worked was that I would loan you money and you—get this—would promise to pay me back more than that. Why would you do something so crazy? Because that was the only way to convince me to part with my money in the first place. Not only that, but there'd be plenty of other people who'd want me to lend to them instead, so you'd have to outbid them too.
That, at least, is how it was for the first couple millennia of financial history. In other words, up until a few years ago. But now central banks are doing what didn't seem possible before: cutting interest rates into negative territory. Switzerland has gone the furthest with a negative 0.75 percent rate; Denmark isn't far behind at negative 0.65 percent; Sweden actually just cut its rate even deeper to negative 0.5 percent; the eurozone is at negative 0.3 percent and maybe more soon; and Japan just joined the club last month with a negative 0.1 percent rate. This has not only pushed short-term borrowing costs below zero, but, in the case of Switzerland and Japan, even 10-year rates too. In all,over $7 trillion worth of debt has a negative yield now.
Up is down, black is white, and people are paying for the privilege to lend, not borrow. It's about one step away from dogs and cats living together—mass hysteria.
So why are central banks doing this now, and why would anyone ever buy a bond that pays a negative rate? Well, they're cutting rates for the same reason they always do: because growth and inflation are both too low. Negative rates should help that by not only lowering borrowing costs for households and businesses, but also by boosting exporters with a weaker currency. After all, who wants to pay a European bank to hold your money in euros when an American bank would pay you to hold it in dollars? Nobody who can help it. And selling your euros to buy dollars is just another way of saying that there's less demand for euros, so its price falls.
That brings us to the bigger question, though: why on earth would anyone pay their bank to deposit money in it? That's what was supposed to make negative interest rates inconceivable. People would just start holding their money in cash that didn't cost them anything instead of a bank account that did—right? Well, it turns out cash does not mean what you think it means. At least not for negative interest rates that are only slightly so. As Paul Krugman points out, keeping your money in cash isn't free assuming you don't just stuff it in your mattress. Safes cost money, and as long as negative interest rates cost less, people will keep their money in banks. Nobody knows where that is, but somewhere around a negative 2 percent rate seems right.
The only problem with negative interest rates is that our financial system wasn't built with them in mind as even a possibility. Banks, you see, don't like to pass the full cost of negative rates on to their depositors for fear of losing them, but do feel like they have to pass the full benefits of negative rates on to their borrowers for fear of losing them to a competitor. That means that their interest income—the difference between what they pay to borrow and charge people to borrow—is squeezed even more than it already was when rates venture into negative territory. How big a deal is that? Just take a look at the chart below: Japan's financial stocks have fallen 25 percent in just the two weeks since they introduced negative rates.
Who could have known: it's tough to make money from lending when you have to pay to lend.
Source: Bloomberg
Source: Bloomberg
If negative hurt bank earnings so much that they cut back on lending—which, to be clear, hasn't been the case so far—then it's possible that they wouldn't help the economy all that much. And that would mean we're in a lot more trouble than we thought. Think about it like this. Central banks around the world are already printing quite a bit of money, but that hasn't been enough to stop global markets from flashing a bright red recession warning. So if it turns out that negative rates don't do much to revive growth, then there's not a lot more central banks can do—or so the story goes. I don't think that's true since central banks can always print more money or promise not to raise rates for a long, long time, but markets are worried it is.
The moral of the story, then, is that you should borrow money if you think have any need for it. There's never been a better time in history.

Cosmic breakthrough: Physicists detect gravitational waves from violent black-hole merger

11:01 AM | BY ZeroDivide EDIT
Scientists announced Thursday that, after decades of effort, they have succeeded in detecting gravitational waves from the violent merging of two black holes in deep space. The detection was hailed as a triumph for a controversial, exquisitely crafted, billion-dollar physics experiment and as confirmation of a key prediction of Albert Einstein's General Theory of Relativity.
It will also inaugurate a new era of astronomy in which gravitational waves are tools for studying the most mysterious and exotic objects in the universe, scientists declared at a euphoric news briefing at the National Press Club in Washington.
[A brief history of gravity, gravitational waves and LIGO]
"Ladies and gentlemen, we have detected gravitational waves. We did it!" declared David Reitze, the executive director of the Laser Interferometer Gravitational-wave Observatory (LIGO), drawing applause from an  audience that included many of the luminaries of the physics world. The briefing was watched around the world by physicists who have long waited for such a detection.
Some of the scientists gathered for the announcement had spent decades conceiving and constructing LIGO.

From 'natural place' to gravitational waves: Gravity in 90 seconds

Play Video1:34
From Aristotle to Einstein, the world's greatest minds have long theorized about gravity. Here are the highlights, and where the study of gravity is headed next. (Gillian Brockell,Joel Achenbach/TWP)
“For me, this was really my dream. It’s the golden signal for me," said Alessandra Buonanno, who started working on theoretical models of gravitational waves in 2000 and is now a professor at Germany's Max Planck Institute for Gravitational Physics.
The observatory, described as "the most precise measuring device ever built," is actually two facilities in Livingston, La., and Hanford, Wash. They were built and operated with funding from the National Science Foundation, which has spent $1.1 billion on LIGO over the course of several decades. The project is led by scientists from the California Institute of Technology and the Massachusetts Institute of Technology, and is supported by an international consortium of scientists and institutions.
[Why this famous physicist tweeting rumors about gravitational waves]
LIGO survived years of management and funding turmoil, and then finally began operations in 2002. Throughout the first observational run, lasting until 2010, the universe declined to cooperate. LIGO detected nothing.
Then came a major upgrade of the detectors. LIGO became more sensitive. On Sept. 14, the signal arrived.
Though only a "chirp," it was a clear, compelling signal of two black holes coalescing, LIGO scientists said. It lasted less than half a second, but it captured, for the very first time, the endgame of two black holes spiraling together.

A bird's eye view of LIGO Hanford's laser and vacuum equipment area, which houses the pre-stabilized laser, beam splitter, input test masses and other equipment. (Caltech/MIT/LIGO Lab)
"This was truly a scientific moonshot," Reitze said during the announcement. "I really believe that. And we did it. We landed on the moon."
These black holes were each approximately the diameter of a major metropolis. They orbited one another at a furious pace at the very end, speeding up to about 75 orbits per second — warping the space around them like a blender cranked to infinity — until finally the two black holes became one.
[This is what it looks like when a black hole tears a star apart]
The pattern of the resulting gravitational waves contained information about the nature of the black holes. Most significantly, the signal closely matched what scientists expected based on Einstein's relativity equations. The physicists knew, from supercomputer calculations and theoretical models, what gravitational waves from merging black holes ought to look like — with a rising frequency, culminating in that chirp, followed by a "ring-down" as the waves settle.
Gabriela Gonzalez, a physics professor at Louisiana State University who is the spokesperson for LIGO, revealed images of the waves picked up by the two detectors and then played an audio version of the same signal.
"Did you hear the chirp? There's a rumbling noise, and then there's a chirp," she told the Press Club audience. "That's the chirp we've been looking for."

Power recycling optic 2. (LIGO)
This cosmic chirp was picked up by both the Louisiana and Washington state detectors. It was such a strong signal that everyone knew it was either a real detection of a black hole merger, or "somebody had injected a signal into the interferometers and not properly flagged it into the data set. It turned out that fortunately that wasn’t the case,” as Reitze put it in advance of the news conference.
He said the team, knowing the checkered history of gravitational wave detections that were later discredited, took special care to have the results verified and peer-reviewed prior to the big announcement. The scientists even looked for the possible handiwork of a computer hacker, Reitze said. All reviews held up.
[Cosmic smash-up: BICEP2’s big bang discovery getting dusted by new satellite data]
The LIGO success has been a poorly kept secret in the physics world, but the scientists kept their historic paper detailing the exact results secret until Thursday morning.
"I didn't tell my wife until a few days ago," LIGO co-founder Kip Thorne, a theoretical physicist at Caltech, said amid a scrum of reporters after the announcement. He said he'd been involved with efforts to register  gravitational waves since the 1960s. "What I feel is just profound satisfaction."
There is no obvious, immediate consequence of this physics experiment, but the scientists say this opens a new window on the universe. Until now, astronomy has been almost exclusively a visual enterprise: Scientists have relied on light, visible and otherwise, to observe the cosmos. But now gravitational waves can be used as well.
Gravitational waves are the ripples in the pond of spacetime. The gravity of large objects warps space and time, or “spacetime” as physicists call it, the way a bowling ball changes the shape of a trampoline as it rolls around on it. Smaller objects will move differently as a result — like marbles spiraling toward a bowling-ball-sized dent in a trampoline instead of sitting on a flat surface.
[Einstein's General Theory of Relativity at 100: Put that in your pipe and smoke it]
These waves will be particularly useful for studying black holes (the existence of which was first implied by Einstein's theory) and other dark objects, because they'll give scientists a bright beacon to search for even when objects don't emit actual light. Mapping the abundance of black holes and frequency of their mergers could get a lot easier.

The control room of the LIGO Hanford detector site near Hanford, Wash. (Caltech/MIT/LIGO Lab)
Since they pass through matter without interacting with it, gravitational waves would come to Earth carrying undistorted information about their origin. They could also improve methods for estimating the distances to other galaxies.
LIGO scientists said they are analyzing additional data from the observational run lasting from September to early January, and that they may find other signs of black hole mergers. One candidate for such an event, picked up in October, is still being analyzed, they said.
“The geometry of spacetime gives a burp at the end of [the merger],” said Rainer Weiss, an MIT professor of physics emeritus who has labored on LIGO since the 1970s.
[European probe launched in a search for ripples in space-time]
No one had ever seen direct evidence of “binary” black holes – two black holes paired together and then merging. The Sept. 14 signal came from about 1.3 billion light years away, though that's a very approximate estimate. That places the black hole merger in very deep space; the signal that arrived in September came from an event that happened before there were any multicellular organisms on Earth.
The reason that gravitational waves have been so difficult to detect is that their effects are tinier than tiny. In fact, the signals they produce are so small that scientists struggle to remove enough background noise to confirm them.
LIGO  detects gravitational waves by looking for tiny changes in the path of a long laser beam. In each of the lab's two facilities, a laser beam is split in two and sent down two perpendicular tubes 2.5 miles long. Each arm of the beam bounces off a mirror and heads back to the starting point. If nothing interferes, these two arms recombine at the starting point and cancel each other out.
But a photodetector is waiting in case something goes wrong. If the vibration of a gravitational wave warps the path of one of the lasers, making the two beams almost infinitesimally misaligned, the laser will hit the photodetector and alert the scientists.
To catch movement that small, scientists have to filter out ambient vibrations all the time. And sometimes even seemingly perfect results can end in disappointment: To prevent false positives, LIGO has an elaborate system in place to occasionally inject ersatz signals. Only three scientists on the team know the truth in such cases, and in at least one instance their colleagues were prepared to publish the results when they finally revealed the ruse.
This fail-safe gave pause to many scientists when rumors about the LIGO detection began to circulate in recent months. But the team confidently confirmed that its readings were not falsely injected – it really spotted a pair of black holes.
One of the two black holes had a mass about 36 times greater than our sun. The other registered at 29 solar masses. Both were rather massive as black holes go -- 10 solar masses is more typical.
“For the first time we have a signature of the heavy black hole forming. That was a surprise,” said Vicky Kalogera, a Northwestern University astrophysicist who has been with LIGO for 15 years. “It wasn’t a vanilla-type of black hole that we had expected.”
When the two black holes came together – spiraling in gradually rather than colliding suddenly in a linear crash – the resulting black hole was not the 65 solar masses you'd expect from basic arithmetic, but only 62. The rest was converted to energy that radiated across space in a grand gravitational burp.
[BICEP2's controversy highlights the challenges for modern science]
That burp first reached the LIGO facility in Louisiana, then the one in Washington state just 7 milliseconds later. The sequence is important, as it allowed physicists to chart the black-hole collision back to somewhere in the southern sky. And the incredibly brief time delay supports something that theorists have long believed about gravitational waves: They move at the speed of light.
“This is the most direct test of our concepts of black holes,” said David Spergel, an astrophysicist at Princeton who was not part of the LIGO team.
The scientists are scrutinizing their data for signs of other violent cosmic events. LIGO's sensitivity continues to improve, and meanwhile other labs will work to catch up to their findings.
“This is such a fantastic new window into the universe – all the rules are different,” said Michael Turner, a University of Chicago cosmologist who also was not involved with the new discovery. “This is the Galileo moment of gravity waves.”

A black-hole collision sounds like a dramatic event, but it’s not really the big news for the physicists. The headline is that LIGO finally worked. Success in detecting gravitational waves is a win for Big Science and for the institutions that backed the project.
“It had a very rough beginning,” Weiss said. “The [National Science Foundation] had a tough time explaining to other people why they would back such a crazy thing.”
Einstein’s theory led to the prediction of gravitational waves, but, as Weiss noted, “Even Einstein wasn’t very sure about this.”
LIGO is still only about a third as sensitive as it is designed to be, and improvements in coming months should let it pick up signals from deeper regions of space, the scientists said.
Caltech's Thorne, who has written extensively about black holes, warped space and time travel, shot down one speculative thought about the implication of LIGO.

“I don’t think its going to bring us any closer to being able to do time travel," he said.

A brief history of gravity, gravitational waves and LIGO

10:43 AM | BY ZeroDivide EDIT

A brief history of gravity, gravitational waves and LIGOThis has turned into Gravity Week here in Washington. Loads of journalists (many in town for the annual meeting of the American Association for the Advancement of Science) crammed into the National Press Club on Thursday morning for a news conference to discuss an experiment called LIGO, which stands for Laser Interferometer Gravitational-Wave Observatory.

And here's the bulletin, straight from the presser: LIGO worked. Scientists announced that they have detected a powerful gravitational wave from the violent merging of two black holes roughly a billion light-years away.
[Physicists detect gravitational waves from violent black-hole merger]
As we ponder the big news, let’s mull gravity and why it’s been such a mysterious force for so long.
Gravity is invisible, as you may have noticed, and a little bit spooky, because it seems to reach across space to cause actions at a distance without any obvious underlying mechanism. What goes up must come down, but why that is so has never been obvious.
Physicists tell us there are four fundamental forces in the universe: Gravity, electromagnetism, the strong nuclear force and the weak nuclear force. Of these, gravity is the most anemic, and yet over cosmic expanses it has shaped the universe. In our solar system, it governs the planets and moons in their orbits. On Earth, it motivates the apple to fall from the tree. You can feel it in your bones.

In this artist’s conception, a binary black hole produces gravitational waves that travel outwards and carry energy away from the system. (NASA/GSFC)
Aristotle believed that an object fell to Earth because it sought its natural place. Heavier objects, Aristotle believed, fell faster; weight was an inherent property of the object.
In the late 16th and early 17th centuries, Galileo brought scientific experiments into the conversation, and he discovered that a heavy object and a light object actually fall at the same speed. One biographer claimed that he proved this by dropping two spheres from the Leaning Tower of Pisa, but the story may be apocryphal. (In 1971, Apollo 15 moonwalker David Scott did his own version of the experiment, dropping a geologist's hammer and a feather and showing that they hit the lunar surface simultaneously.)
[Cosmic smash-up: BICEP2’s big bang discovery getting dusted by new satellite data]
Galileo also discovered that objects always fall with constant acceleration and along a parabolic curve. “Galileo’s observation that all falling objects trace a parabola is one of the most wonderful discoveries in all of science,” physicist Lee Smolin writes in his book “Time Reborn.”
Then came Isaac Newton. In the second half of the 17th century, he developed a universal law of gravity. He calculated that the attraction between two bodies was equal to the product of their masses divided by the square of the distance between them. This is true on Earth as well as in space. It explains the tides. It explains the motions of the planets around the sun. This is a basic law of nature, true anywhere in the universe.
But even Newton admitted that he didn’t understand the fundamental nature of this force. Newton could describe gravity mathematically, but he didn’t know how it achieved its effects.
In the early 20th century, Albert Einstein finally came up with an explanation, and it's rather astonishing. First he grasped that gravity and acceleration are the same thing. His General Theory of Relativity, formulated in 1915, describes gravity as a consequence of the way mass curves "spacetime," the fabric of the universe. It's all geometry. Objects in motion will move through space and time on the path of least resistance. A planet will orbit a star not because it is connected to the star by some kind of invisible tether, but because the space is warped around the star.

Albert Einstein writes out an equation on the blackboard at the Carnegie Institute, Mt. Wilson Observatory, headquarters in Pasadena, Calif., in this Jan. 14, 1931 photo. (AP)
“Gravity, according to Einstein, is the warping of space and time,” Brian Greene wrote in his book “The Elegant Universe.”
The physicist John Wheeler had a famous saying: “Mass grips space by telling it how to curve, space grips mass by telling it how to move.”
Einstein's great theory has been tested and retested and has always come out on top. Most famously, the British astronomer Arthur Eddington observed a solar eclipse in May 1919 and concluded that starlight passing close to the sun was, indeed, bent in a manner consistent with Einstein's theory. Eddington's endorsement triggered global publicity for Einstein that made him a celebrity and the personification of scientific genius.
[BICEP2's controversy highlights the challenges for modern science]
One of the predictions of Einstein’s equations (though Einstein himself wasn’t ready to buy in fully) was the existence of gravitational waves – ripples in the spacetime fabric. Scientists in subsequent decades looked for such waves to no avail. The University of Maryland physicist Joseph Weber built gravitational-wave detecting devices and claimed to have discovered such waves, but his claims were disputed and ultimately discredited. But there were physicists who were not ready to give up the quest, and they ultimately persuaded the National Science Foundation to fund the creation of LIGO, which has two facilities, one in Livingston, La., and the other in Hanford, Wash.
LIGO had its detractors from the very start because it was going to be expensive and might detect nothing at all. These waves, if they existed, would be extremely subtle. It’s not like picking up the vibration from a passing truck. The gravitational waves, in theory, should contract or expand space by an almost infinitesimal amount. A detector a couple of miles long might become longer or shorter by less than the width of a subatomic particle.
Gravitational waves pass through everything and can't be directly captured. So the two LIGO facilities use a laser beam to try to deduce the passing of a gravitational wave. The beam is split in two, with each part bouncing off mirrors perched at the end of perpendicular, airless tubes about 2.5 miles long. When those cleaved beams again converge, they should align perfectly — unless some invisible gravitational waves have come trundling through the building, stretching one tube or compressing another and thereby changing the distances traveled by the beams.
One of the controversies over LIGO was simply about the name. Was it really an “observatory”? Some astronomers weren’t ready to go there. Astronomy has always been a science built around light. When astronomers talk about observing in the optical, the infrared, or with radio waves or gamma rays or X-rays, they are talking about different wavelengths of light, each creating its own visual picture of the universe.
But gravitational waves represent a new form of cosmic information. As the scientists told us today, it's a new way of seeing the universe — or, to use a better metaphor, of hearing the universe. Physicists say this is like adding sound to what we can already see.
The movie of the universe has always been spectacular, but it will be even better with sound.

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