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Big Bang's Smoking Gun Found
astroengine writes "For the first time, scientists have found direct evidence of the expansion of the universe, a previously theoretical event that took place a fraction of a second after the Big Bang explosion nearly 14 billion years ago. The clue is encoded in the primordial cosmic microwave background radiation that continues to spread through space to this day. Scientists found and measured a key polarization, or orientation, of the microwaves caused by gravitational waves, which are miniature ripples in the fabric of space. Gravitational waves, proposed by Albert Einstein's General Theory of Relativity nearly 100 years ago but never before proven, are believed to have originated in the Big Bang explosion and then been amplified by the universe's inflation. 'Detecting this signal is one of the most important goals in cosmology today,' lead researcher John Kovac, with the Harvard-Smithsonian Center for Astrophysics, said in a statement."
Pretty damn cool.
news two years ago
My hat's off too all the hard-working, dedicated cosmetologists that made this possible.
A direct detection of a gravitational wave moving the mirrors of a large scale interferometer is up next. In the next few years, Advanced LIGO (US), Advanced Virgo (Italy) and KAGRA (Japan) will come online with the hope of directly detecting gravitational waves from sources such as supernovae and coalescing binary star systems. With this kind of network, it will then be possible to coordinate both electromagnetic and gravitational searches of our sky. This is useful for many reasons, one of which is that it lets us listen to the sound of black holes colliding where no light escapes.
Exciting times!
If they thought finding gravitational waves was hard, just wait until they try to locate a drooling autotroph.
Einstein's theories continue to astound.
"Inflation" and "expansion" are VERY different when talking about cosmology - some journalist flipped those two words. They supposedly found evidence of inflation, which is a big deal. Finding evidence of expansion is very very old news - like first half of the 20th Century old.
We already have plenty of direct evidence for the expansion of the universe. See redshifting of galaxies etc.
This announcement is about inflation - a particular period of rapid expansion immediately after the big bang.
Creationists will now say the Big Bang was part of God's plan.
Astro physics 1 Theoretical physics 0
I think we should spend more resources on astro physics.
Better ten new super space telescopes than one new super proton smasher.
Ok, fine. But is it webscale ?
There are three problems in cosmology that inflation solves: flatness: the universe is very close to its critical density, the horizon problem: the universe looks like it is in thermal equilibrium for no good reason, and absence of magnetic monopoles.
While it is unlikely that anybody will bother to attempt to replicate the discovery of these gravity waves, as nobody wants to realize it was just a unit conversion error, what people do know is that Dice has sucked the life out of Slashdot. Come join us on comp.misc, and if your ISP no longer provides Usenet look up Eternal September.
Brian Greene is going to be there defending his hare-brained "predictions" so it should be a lot of fun for everybody.
Note that this the second indirect evidence for the existence of gravitational waves, the first one was the orbital decay of a binary system that included a pulsar, discovered by Hulse and Taylor (Nobel Prize 1993). Today's result, if confirmed, seems pretty spectacular, and might be rewarded with a second Nobel Prize. For a first direct detection of gravitational waves, we have to wait for first detections by LIGO, Virgo and eLISA.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
I think we should all wave back!
Some interesting perspective from Matt Strassler, who's a particle physicist at Harvard.
He points out that this is still an *indirect* observation of gravitational waves (and not the first one) and that the results look sensibly in line with some predictions from inflation. And that while this is a tremendous experiment, it's not any kind of "smoking gun", and we really need to wait for replication to get properly excited.
All opinions expressed herein are not my own; I haven't had free will since last year when aliens ate my brain.
If gravity waves exist, wouldn't that imply that gravitrons exist as well? Otherwise it would be like having water waves without water...
Incorrect. Or, rather, been shown to be false by the evidence. And it was such a damn elegant model, too. Bravo to the team of researchers who've been working a decade on this satellite and these observations. I believe Neil and another scientist had a small bet about this, so he's also out of pocket a few dollars. Now we just have to hypothesise new ideas that will eliminate the many kludgy math bits out of Big Bang model. This news, and 120 more BlackBerry jobs lost today, means a sad day here in Waterloo (at the Perimeter Institute).
DaveyJJ
Can we use the orientation of these waves to calculate a point of origin relative to ourselves?
That would be awesome. I would like to face that direction when I pray.
Crowbar? BICEP? What's next, the theoretical physicist responsible for the discovery just happens to be named Gordon Freeman?
Man I would love to ride one of those waves... to infinity and beyond!
"I have made the earth, and created man upon it: I, even my hands, have stretched out the heavens, and all their host have I commanded" (Isaiah 45:12.) God is very far ahead of you in saying this is what happened.
its time to get rid of the silly but widespread idea of inflation coming from a singularity point source. The universe was hot, dense and still probably infinite, it just started to inflate locally. We probably will never know exactly what was before, but thinking it all came from a point source seems a little silly.
http://scienceblogs.com/starts...
This was the old news...
Basically sifting through information gathered from older CMB detectors, they discovered a statistical B-mode in the data that could have come from gravitational wave that occurred during inflation, but the data was really too noisy to be sure.
The new news is they used a new detectors which are capable of making cleaner measurements to convince themselves that the detected B-mode was unlikely to come from gravitational lensing after the big-bang. The current evidence apparently is consistent with the B-mode coming from a gravitational waves that are predicted to occur during the inflationary period of the universe.
If I understand correctly they measured the polarization of the 2.73 background radiation of the Universe. But at these temperature you only have radio waves, how do you detect their polarization? Moreover with an instrument that looks like e telescope on the picture? Can someone enlighten me?
Did you hear that? That was the sound of millions of religious zealots pressing their palms harder against their ears and screaming LA LA LA even louder.
osr chair, return
The gun is the universe. These people only found the smoke. Not the smoking gun.
Collasping universes do.
Yes, if the measurments can be confirmed for different (and hopefully bigger parts of the sky), the cyclic model of Turok and Steinhardt seems to be very unlikely now, as it has predicted a very small polarisation of the cosmic microwave background.
What puzzles me, is that neither the WMAP probe nor the Planck probe have found a polarisation and now the polarisation was found with a ground based telescope? The resolution of the WMAP probe was probably too low, but the planck probe has had a much higher resolution.
Sven
P.S.: An explanation and comparison of both, the big bang inflationary model and the cyclic model featuring Dr. Paul J. Steinhardt:
http://www.youtube.com/watch?v...
First of all, how is it that all stars moving apart from each other rapidly is not "first direct evidence" of the universe's expansion? And secondly, how could the expansion of the universe amplify gravitational waves? Space stretching would thin out the waves because they would be expressed over a wider area. Also, you don't create more gravity without adding mass or energy. Neither is occurring due to universe expansion, and of course the fact that mass and energy can't be "created" under any circumstances anyway.
The real mystery to me is why any nerd would be willing to embrace fiction built around the idea that we need the beautiful people extend their olive branch to help the poor, retarded geniuses.
Cloudiot: A person who does not see offsite storage as a way to lose control over access to his or her own data.
And the official position of the Catholic church is that the creation account in Genesis is metaphorical. The first documentation of this (that I know of) came from St Augustine a mere 100 years after the Bible was canonized.
Mainline protestants tend to consider Genesis (and the rest of the Bible, too) as being metaphorical, as well (with plenty of lively conversation about what all the metaphors mean). It is really just the fundamentalists which are stuck on literalism.
So, they have this evidence in a box or something?
Forgive me if this sounds stupid, but I was under the impression that all measurements of gravity, radiation and electromagnetism were indirect by nature.
"For the first time, scientists have found direct evidence of the expansion of the universe,"
Yes, that's exactly what happened today.
*facepalm*
Good grief. Do you mean there is no one here that can imagine a great voice saying "let there be light..." then then BANG! the birth of the universe? Must we forever live with the ridiculous science-versus-God fighting, when, as just demonstrated, they actually go together? Darwin himself was a religionist when he began his epic journey. The overwhelming evidence of evolution convinced him that species do change and mutate. Why wouldn't they? Most of the first generation of creatures could not adapt, and so died off.
Lastly, do not forget the scriptures that mention how thousands of years are like one day to God.
This should get me flamed like a pig on a spit from all sides...
Science is a process of discovery, and we need to be open to alternatives that are not disproven. The expansion of the universe is a great example of this. Everybody "knows" that the universe is expanding and that this indicates a Big Bang is the most likely origin story. But technically, all we have observed is that there is a correlation between distance and red shift, assuming that absorption spectra are constant over space/time and light doesn't chance frequency in travel. We have not actually observed that distant galaxies are actually moving away from us. We literally have no direct evidence that the universe is expanding. It's a theory. Not proven fact.
To put a more fine point on it, we know (can demonstrate experimentally) that relative motion is _a_ cause of red-shift, and we observe red-shift. We have not, in fact, observed this relative motion on scales large enough to demonstrate universal expansion. This is an indirect measurement believed to be reliable, but not proven. We can only observe relative motion on very close things via parallax, and we've found that some things are coming towards us, so relative motion locally is not dominated by expansion. We rely on the theory. It could be wrong.
A viable alternate theory is that light gives up some energy while traveling extremely long distances, which shows up as red-shift. Where does the energy go? It could be the source of energy for the CMBR. It could go somewhere else. In any case, as a theory, it explains the red-shift just as well as expansion. Another viable alternate theory is that the absorption/emission spectra of atoms differs with space/time. Perhaps atoms farther away or longer ago created and absorbed light at lower frequencies, this making older light appear red-shifted by current frequency comparisons. This theory is even harder to test, but just as good at explaining the observations.
As a scientist, remember the difference between theory and proof.
--Jaborandy
"And it was such a damn elegant model, too."
You evidently have a different definition of "elegant" to me. My definition of "elegant" does not include "theories containing hand-crafted and unjustified potentials of a strikingly bizarre form inserted purely phenomenologically into a theory that is a phenomenological attempt to see what might happen if some facets of M theory are put onto large scales". That's not to defend inflation too much but the potentials of inflatons are typically quadratic or quartic, which is a lot neater than the potential in ekpyrosis, and the setup with two infinite, flat branes is at least as contrived as the inflaton.
All of that said, let's wait until the dust settles before we rule models out based on gravitational radiation alone. Their position is certainly looking somewhat precarious, but there may be ways out yet.
ixnay on the OSTSHay! You don't want to raise him up!
There is nothing in genisis on how it was created? source please...but if the magic wave of the hand is what you need, you should reference harry potter? Please stop the hate. And be accurate, he spoke a word, that word could have been big bang theory, or super string or gravitational pulsing, remember you are looking at what was done from the viewpoint of 1500 years ago.
nice...was going to post this but I wouldn't have explained it as well...
honest quesiton: do you think what you described is commonly understood among physicists? It seems to me, and I of course could be wrong, that alot of stuff I see on /. is conflating what happens *on the event horizon* with the actual black hole itself
I even got into a discussion with the editors of the Black Hole wiki...the first sentence is the maxim "BH is a region of space from with nothing, even light, can escape"
Thank you Dave Raggett
Hey, no, that's great man. Whatever floats your boat.
You can actually say pretty much anything you want about what happened before the big bang. It could be a guy in a lab quoting a book sarcastically right before he flipped the switch and blew up the universe. It could very much be an all powerful all knowing god who set in motion all that ever happened with the expressed purpose of bringing about life on earth. We dunno.
As for everything happening after the big bang, it's cool as long as you take the whole thing as a metaphor. A story by ignorant barbarians for the purpose of filling a gap in their knowledge with a placeholder. And now we know better and we have more details of what actually happened. As long as you don't presume the story is literal and more correct then what actually happened, as long as that placeholder doesn't command you to slaughter the infidels or vote for a shmuck, then yeah, we're cool.
Lastly, do not forget the scriptures that mention how thousands of years are like one day to God.
Still kinda off by a few magnitudes. Age of the universe is ~14 billion years. Our sun formed ~4.57 billion years ago and earth formed after that.
Similes are fine too. It's "like" thousands of years. "like". If you squint hard enough the story kinda matches the observed truths.
and remarkable naive and arrogant, for a species who don't even know how her own planet came to be, or herself for that matter, to claim that she now knows how the whole universe came to be. "Because science"-rebuttals? Don't bother.
Man does belief things he doesn't understand, spout meaningless statement to show everyone how ignorant he is: news at 11.
The Kruger Dunning explains most post on
A gravity wave is a phenomenon in fluid dynamics: http://en.wikipedia.org/wiki/Gravity_wave
A gravitational wave is a disturbance in the fabric of spacetime: http://en.wikipedia.org/wiki/Gravitational_wave
Could you let me know which bits are meaningless and betray ignorance? Genuine question.
The new observations have a lot to do with testing the theory of inflation, but they are not really focused on the Big Bang. The Big Bang has the observed expansion of the universe, the age of the oldest globular clusters, the existence of the cosmic microwave background and the theory of primordial nucleosynthesis to support it. If you run the expansion backwards, you shrink to a point in finite (backwards) time. That the oldest globular clusters of stars are just a little younger than that, that the cosmic microwave background shows the universe was hot and uniform in the past, all gas and no stars, and that the ratio of primordial elements shows that it was even hotter further back in the past but that element formation was quenched by the cooling of the expansion, these things support the Big Bang theory You don't really need a smoking gun when the artillery has already laid down a barrage. These new observations take advantage of the pristine nature of the cosmic microwave background to test some ideas about what happened before the elements formed. But inflation theory is an elaboration of Big Bang theory, not really a proof.
This is the first direct evidence for gravity waves, but another very clever indirect one earned a Nobel Price in 1993.
Oh, I forgot about this crowd....instead, i am hip deep in sarcasm. oh, well.
Too bad very few can even understand what they are talking about. But dose it mention how this is helpful to know this? So this is how God made the universe, or how it simply randomly made. So what?
How do you count "days" before the Earth and the Sun are formed?
"Computer models indicate that the universe expanded by 100 trillion trillion times in .0000000000000000000000000000000001 (10 to the minus-34) seconds after the Big Bang explosion 13.8 billion years ago."
So, I assume the universe started out as a singularity (another blackhole from another universe, popping like a big pimple to create our universe?) But, really, my question is what is the measurement of a singularity? It has to be 100 trillion trillion times something. I assume that since a planck volume (V=4/3 pi planck length^3) is the smallest volume you can have, then it would be 100 trillion trillion times that?
and why does this editor strip out special characters like pi, etc?
I thought this was discovered a long time ago - the cosmic background radiation from the big bang.
Planck is due to report it's first tranche of data in August, IIRC.
Being first still matters. As the guys who got the Nobel in 1993 for showing that the loss of energy from a pair of co-orbiting neutron stars is consistent with the expected radiation of gravity waves will be fastidious about not pointing out. While wearing big cheesy grins. And gold medals.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
GR says photons lose energy going uphill.
We see red shift in all directions.
So all directions are uphill.
Uphill both ways, barefoot in the snow, coming and going to school.
Now get that neutrino detector off my lawn.
--
To wake with a start and shudder from a lecture you are delivering
Send them all off in a spaceship together with some telephone sanitizers and advertising executives.
I think this "expansion" is actually called "inflation" - the theory suggested by Alan Guth as the explanation for the overall uniformity of the Universe ?