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How We'll Someday Be Able To See Past the Cosmic Microwave Background
StartsWithABang writes: When it comes to the farthest thing we can see in the Universe, that's the Cosmic Microwave Background, or the leftover glow from the Big Bang, emitted when the Universe was a mere 380,000 years old. But what, exactly, does this mean? Does it mean that we're seeing the "edge" of the Universe? Does it mean that there's nothing to see, farther back beyond it? Does it mean that, as time goes on, we're going to be able to see farther back in time and space? The answers are no, no, and yes, respectively. If we want to see farther than ever before, we've got two options: either wait for more time to pass, or get moving and build that cosmic neutrino background detector.
As soon as somebody replaces the 17 year old microwave in the cafeteria of the observatory, since scientists can't be bothered to wait until the cycle is done.
Muslims hate us this we know
For the Qur'an tells us so
Little children all could be
Killed or raped by a muzz-zee
Your #1 source for links to medium.com
Can we lose the daily barrage of pop-sci please.
Gee... I wonder who the linked astronomy-related Slashdotted story will have been written by.
Click...
Yup. Thought so. Is there nobody else writing astronomy blogs these days? Or is Slashdot just in love with Ethan?
It's not like it's going anywhere, right guys?
Allah hates us it is true
He hates God and me and you
Nothing else is half as vile
As his "prophet" peaedophile
The neutrino is the trendy particle, now?
Bah! Wake me when the tetryon is discovered.
of turning slashdot into a walhalla for clickbait.
So how do they know that the "background" microwaves are from the edge of the universe? I thought that the primordial microwaves are scattered throughout the universe, so what we see when we look in some direction is the sum of all the background microwaves coming from that direction.
If we're actually seeing the edge, doesn't that shoot down the idea that the universe doesn't actually have an edge, and everywhere appears to be at the "center" of the universe? How was this idea disproved? I seem to have missed the discovery of an actual edge, somehow.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
>> The answers are no, no, and yes, respectively.
If I'm reading this right, you just said:
But what, exactly, does this mean? no
Does it mean that we're seeing the "edge" of the Universe? no
Does it mean that there's nothing to see, farther back beyond it? yes
Does it mean that, as time goes on, we're going to be able to see farther back in time and space? (no response)
Amongst all the /. arguments, I would like to say that that is a well written article. It gets a very complex point across in a way that is easily understood. I didn't realize previously that our view of the CMB would change over time. Makes sense, we see the CMB who's light happens to get here now.
The microwave background radiation is what remains from the red-shifting of a burst of light when electrons became bound to protons and was stretched by the subsequent expansion of space. Wasn't there an earlier burst, of gamma rays, when quarks condensed from the quark-gluon plasma to form baryons? Has that been absorbed/scattered to obscurity by interaction with matter since then? Why hasn't the microwave background has not similarly been obscured by interaction with matter (exciting rotational energy levels of molecules?)
IANAP, but from what I read in most models of inflation there should be primordial gravitational waves, which could be indirectly detected based on the polarization of the CMB (b-modes). These waves (if they exist) would go all the way back to the inflationary period itself.
The BICEP2 experiment was designed to look for these, and last year announced detecting b-modes in the CMB. Of course, as we now know thanks to Planck their discovery is probably due to dust polarization. Are there any current or planned experiments that could differentiate between dust polarization and potential gravitationally-caused polarization?
Does it mean that, as time goes on, we're going to be able to see farther back in time and space?
Obviously the answer is yes because, as time goes on, the period at which the CMB was emitted moves further into the past so obviously we are seeing "further back in time" but only at the rate of one year further per year past (on average). Since the universe is also expanding we are also looking further. This is about as insightful as pointing out that as time goes by I can remember events further back in time.
Medium.com: Because Small.com and Large.com don't exist.