Physicists have announced the discovery of gravitational waves, ripples in spacetime first anticipated by Albert Einstein a century ago.
“We have detected gravitational waves. We did it,” said David Reitze, executive director of the Laser Interferometer Gravitational-Wave Observatory (Ligo), at a press conference in Washington.
The announcement is the climax of a century of speculation, 50 years of trial and error, and 25 years perfecting a set of instruments so sensitive they could identify a distortion in spacetime a thousandth the diameter of one atomic nucleus across a 4km strip of laserbeam and mirror.
The phenomenon was detected by the collision of two black holes. Using the world’s most sophisticated detector, the scientists listened for 20 thousandths of a second as the two giant black holes, one 35 times the mass of the sun, the other slightly smaller, circled around each other.
Still pondering a reply, TJ?
Work kept me from noticing.
Its an odd question really though.
The known universe is all we have to work with. The "space" for the universe to expand into, and "space" as in what's in an empty box, and the "space" in spacetime, are not really the exact same thing.
Time runs into the same language limitations, leading to seeming conundrums as statements such as "If time is infinite, why is there never enough of it?", and so forth.
There is nothing in cosmology that will not allow infinite space, or, multiple big bangs going off in the far reaches of whatever is out there,
There are no indications that the known universe comprises everything...and that there is nothing outside of the known universe.
Sure, write "There be dragons" on whatever is outside the known universe if it makes you happy...but, I'll go with simply more space.
We KNOW the universe is expanding...and, it has to expand into somewhere to do so...so, logically, spacetime is expanding into the space and time that exists outside of our known universe.
If you want to call what's outside "another universe", so there are multiverses, that concept is within current cosmolgy at least.
We don't KNOW what is outside of the known universe, hence, the "known" part.
What we DO know is that space cannot have an end point, and, neither can time.
When humans talk about or understand time, it is marked by events that happen with perceivable patterns possessed of regularity. How often a planet transits its orbit, how often the planet rotates, how many times a heart beats. The quantum foam of space on the quantum level doesn't seem to qualify in that regard. Sidereal time does, but that requires actual matter. When we talk about time existing, we're talking about a universe with matter in it, and not just any sort of matter. Large-scale matter. I'm not sure in what sense "empty" (except for quantum foam) space can have time. It seems to be space minus time, time beginning when matter shows up in it.
Personally, my gut instincts (as contrasted with expertise in cosmology, etc, for example...), tell me....
Thank you, TJ, for revealing the capability of your gut instincts relative to the capability of your expertise in cosmology, etc,.... I will keep it in mind.
It was not so much about capability, as about evidence.
Much as a hypothesis can be based upon expertise and data, but the level of evidence is circumstantial and/or within certain certainty ranges...but a theory will be based upon more substantial evidence and proven predictions made by it, etc.
I try to be clear as to what I base a statement on if appropriate, so as to not confuse hypothesis with theory....so a reader is aware of which level of evidence supports a claim, etc.
Its simply being open minded...and providing some indication as to the evidential weight of a statement.
In this case....the KNOWN universe is all we have data for, and, speculation about the UNknown universe is just that....albeit, logic is a valid tool for such speculation.
there might be an infinite number of big bang events happening at the same time, given the infinite amount of space out there...
Hmm, good thought. Or maybe the so-called multiverse is just one universe, with each big bang happening when enough so-called universes collide?
Yeah, 6 in one scenario, half-dozen in the other.
Aw, the LIGO folk have done what the BICEP2 folk did: they published their finding before its confirmation by other folk who have the required hardware.
They are certainly giving their finding more than provisional acceptance.
One way of putting it is that Space is bounded but infinite.
And quite honestly you need to be infinitely intelligent to understand the subject. Which I'm not.
I'm not sure what "infinitely intelligent" would actually mean. Is intelligence referring to the possession of knowledge, or, to the ability to think?
IQ primarily measures the knowledge acquired for example.