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Yahoo-Answers

Page history last edited by Dalinian 9 years, 12 months ago

About – Here's a place where you can see:

• some of the content I posted to Yahoo! Answers, but which has since been deleted

• some of the answers I composed but didn't get to post (because the asker chose a 'Best Answer' too soon)

• some complex answers in their entireity

Caveat – The graphic items surrounding each answer are screen grabs, for aesthetic mimicry only, so they're not functional-by-clicking like the originals are.




Materialism changes its meaning


   
 

 

Resolved Question

 

When did the word "materialist" change its meaning to "someone who only cares for material possessions"?

 

 

  

 

 

 


 

Best Answer - Chosen by Asker

 

It’s odd that in a ‘Philosophy’ zone, nobody has addressed ‘materialism’ as a philosophical theory. Here’s a reasonable summary:

“In philosophy, the theory of MATERIALISM holds that the only thing that exists is matter; that all things are composed of material and all phenomena (including consciousness) are the result of material interactions. In other words, matter is the only substance. To many philosophers, not only is 'physicalism' synonymous with 'materialism', but they use both words to describe a position that supports ideas from physics which may not be matter in the traditional sense (like anti-matter or gravity). The philosophical alternatives to materialism are some forms of monism (besides the materialistic monism), dualism and idealism.”
~ from ‘Materialism’, Wikipedia – http://en.wikipedia.org/wiki/Materialism

In historical order, this is the primary definition of ‘materialism’, dating back to ancient Indian philosophy, where materialism developed around 600 BCE with the works of Ajita Kesakambali, Payasi, Kanada, and the proponents of the Cārvāka school of philosophy. In European history, philosophical materialism defined itself from the C17 Enlightenment onwards in contradistinction to the dualism of René Descartes, and the idealism of Georg Hegel.

But before the quoted paragraph above, we see, “Not to be confused with Materialistic”:

“MATERIALISTIC describes a person who is markedly more concerned with material things (such as money and possessions) rather than spiritual, intellectual, or cultural values. Not to be confused with materialism.”
~ from ‘Materialistic’, Wikipedia – http://en.wikipedia.org/wiki/Materialistic

So, for instance, I’d describe myself as a non-materialistic dialectical materialist, where:
• non-materialistic = markedly unconcerned with personal material things (such as money and possessions)
• dialectical materialist = philosophically inclined to Marxism and physicalism
» Dialectical materialism – http://www.marxists.org/glossary/terms/d/i.htm

It’s only with capitalism’s recurrent ‘crisis of overproduction’ problems, from the late C19 onwards, that convincing the citizenry to be materialistic consumers has become a part and parcel of ruling class ideology.
» Inevitability of crises of overproduction – http://en.wikipedia.org/wiki/Overproduction#Inevitability
» Consumerism – http://en.wikipedia.org/wiki/Consumerism

Unfortunately, the distinction between the noun ‘materialism’ (a philosophical theory) and the adjective ‘materialistic’ (over-concerned with material possessions) is lost on most people. Ever since Nathaniel Hawthorne back-defined from ‘materialistic’ to get ‘materialism’ as a noun meaning “a way of life based entirely on consumer goods” in 1851, the confusion has only grown stronger.
» ‘materialism’ etymology – http://www.etymonline.com/index.php?search=materialism&searchmode=none

Nowadays, dictionaries usually carry both definitions, often giving primacy to the consumerist definition; eg:

“materialism
noun [mass noun]
1 a tendency to consider material posfs and physical comfort as more important than spiritual values.
2 Philosophy – the theory or belief that nothing exists except matter and its movements and modifications.
— • the theory or belief that consciousness and will are wholly due to material agency. See also dialectical materialism.”
~ Oxford Dictionaries – http://oxforddictionaries.com/definition/materialism

The changing fortunes of ‘materialism’ though centuries of history are an interesting illustration of how some changes to the linguistic superstructure of society are predicated on variations in the economic base upon which it depends. If it helps any, when it’s important to distinguish these two meanings, I’d call the first either ‘vulgar materialism’ or ‘consumerist materialism’.

Share and Enjoy, Peace-&-Love, Dalinian
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A folding bike travels with you inside trains, planes, & automobiles (& on the bus,
tram, taxi, subway, ship, helicopter) ⫸ http://en.wikipedia.org/wiki/Folding_bicycle
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How can solar radiation travel through a vacuum?


  
 

 

 

 

 


 

Best Answer - Chosen by Answerer

 

Hi mny1990,

Not sure if you're ready for an adult answer, but your curiosity does you great credit, so I'm hoping you're a smart teen.

“No other molecules can travel through a vacuum, but solar radiation can.”
Two wrongs and a right: molecules CAN and do travel through a vacuum, solar radiation is NOT made up of molecules, but it CAN travel through a vacuum – and here's how.


SOLAR RADIATION TRAVELS THROUGH A VACUUM
The solar radiation with which we are most familiar is sunshine, which is, as no doubt you know, made up of light. That's because vision is our primary sense, and our eyes evolved to make best use of daylight for meeting our needs, for food, shelter, and defence against predators. However, light is but a small sliver of a much broader phenomenon – electromagnetic radiation:

• Electromagnetic spectrum – graphic with quiz
» pic+text – http://www.lbl.gov/MicroWorlds/ALSTool/EMSpec/EMSpec2.html     

So how come light can travel through the vacuum of outer space? From quantum field theory, we know that there are a number of fields that pervade the whole of our universe...

“In physics, a field is a physical quantity associated to each point of spacetime. A field may be thought of as extending throughout the whole of space. Defining the field as "numbers in space" shouldn't detract from the idea that it has physical reality. It occupies space. It contains energy. Its presence eliminates a true vacuum. The vacuum is free of matter, but not free of field. The field creates a "condition in space".”
~ from ‘Field (physics)’, at The People's Encyclopaedia
» http://en.wikipedia.org/wiki/Field_(physics)

The field responsible for solar electromagnetic radiation is called, not surprisingly, the 'electromagnetic field':

“The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. The field can be viewed as the combination of an electric field and a magnetic field. From a classical perspective, the electromagnetic field can be regarded as a smooth, continuous field, propagated in a wavelike manner; whereas from the perspective of quantum field theory, the field is seen as quantised, being composed of individual particles.”
~ from ‘Electromagnetic field’, at The People's Encyclopaedia
» http://en.wikipedia.org/wiki/Electromagnetic_field

The particles of which solar electromagnetic radiation is composed are called 'photons':

“In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force. The effects of this force are easily observable at both the microscopic and macroscopic level, because the photon has no rest mass; this allows for interactions at long distances. Like all elementary particles, photons are currently best explained by quantum mechanics and will exhibit wave–particle duality, exhibiting properties of both waves and particles.
~ from ‘Photon’, at The People's Encyclopaedia
» http://en.wikipedia.org/wiki/Photon

So you can regard each photon of solar electromagnetic radiation as a ripple in the electromagnetic field, propagating through that field as a wave, travelling at the speed of light. Since the electromagnetic field pervades the whole of our universe, it provides the means by which photons can fly from our Sun, to ourselves on Earth, through the vacuum of outer space, in around eight minutes. And a photon is a photon is a photon, so what’s good for sunshine is good for starlight, galaxy light, and the ‘cosmic microwave background radiation’ (which began its journey to us just after the Big Bang, around 13.7 billion years ago).


MOLECULES ALSO TRAVEL THROUGH A VACUUM
If you’d like to confirm that molecules can indeed also travel through the vacuum of outer space, check out the...

• Cosmic dust
» about – http://herschel.cf.ac.uk/science/infrared/dust
» pix – http://www.google.co.uk/search?q=Cosmic+dust&tbm=isch

...and the...

• Molecular clouds
» about – http://coolcosmos.ipac.caltech.edu/cosmic_classroom/cosmic_reference/molecular_clouds.html
» video, 1:35 – http://www.youtube.com/watch?v=YbdwTwB8jtc

...in the...

• Interstellar medium
» about – http://espg.sr.unh.edu/ism/what1.html
» video, 2:31 – http://www.youtube.com/watch?v=DUkBmURrZjo


Hope that’s broadened your understanding, and given you some pointers for further exploration,

Share and Enjoy, Peace-&-Love, Dalinian
——————————————————————————————————————
...__o....Cycling is the most energy efficient form of transport ever invented, easy,
._ \<,_...fast, healthy exercise, improves self-esteem, & on-going use of a bicycle has
(_)/ .(_)..virtually NO carbon footprint ⫸ http://www.ibike.org/encouragement/benefits.htm
⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶⟶
A folding bike travels with you inside trains, planes, & automobiles (& on the bus,
tram, taxi, subway, ship, helicopter) ⫸ http://en.wikipedia.org/wiki/Folding_bicycle
——————————————————————————————————————
• Web-based research enthusiast
• Cosmology connoisseur
• Physics aficionado

 

 


 

 


Is the universe infinite?


  
 

 

 

 

 


Hi Ignorant,

Questions of the extent and “edge” of our universe depend on two interconnected geometrical factors: local geometry and global topology. But before getting to those, let’s establish what the standard inflationary big bang model of cosmology (the one agreed upon by the great majority of scientists) predicts about the scale of our universe.

We’ve established that our universe is 13.72 billion years old, that it is expanding at an accelerating rate, and that such expansion has swelled out our cosmic horizon to a sphere of around 93 billion light years in diameter. Looking out through our observable universe, we see:
• the structures in our Milky Way galaxy (solar systems, star clusters, nebulae, etc), then
• galactic scale structures (galaxies and quasars, galactic clusters and superclusters), then
• right at the boundary we see cosmic microwave background radiation from the surface of last scattering all around us, emitted only c.380,000 years after the Big Bang, when our universe first became transparent to EM radiation.

Here are a couple of visualisations of our observable universe:


⫸ A. http://i22.photobucket.com/albums/b336/dalinian61/Quora/cosmic_spheres_of_time_1900x1200.jpg  

 

⫸ B. http://upload.wikimedia.org/wikipedia/commons/9/98/Observable_Universe_with_Measurements_01.png  

We believe that the very early universe experienced a very brief burst of cosmic inflation, expanding spacetime exponentially, and taking the great majority of the universe forever beyond our cosmic horizon. For instance, if the universe were to be finite in size, and its spatial extent were to be represented by a blue whale, then our observable universe (that 93-billion-LY-diameter sphere) might be represented by a pea in its stomach. And as you point out, both the whale and the pea are expanding, so even with a near-light-speed spaceship, we couldn’t reach the “edge” of the whale, because it is receding at greater than light speed. (BTW, this does not contradict the general relativity theory’s light-speed universal speed limit – that only applies to objects travelling THROUGH spacetime, such as our spaceship; the expansion of spacetime itself is NOT limited to the speed of light.)

Local Geometry
We know from general relativity that the four dimensional spacetime fabric of reality can be locally warped by the mass of matter embedded within it, which has been confirmed by astronomical observation, such as gravitational lensing. So the question of local geometry is whether the whole of spacetime has a curvature, of which there are only three possibilities: spherical (positive curvature), flat (zero curvature), or hyperbolic (negative curvature), as illustrated here as two-dimensional analogies:

 

http://upload.wikimedia.org/wikipedia/commons/9/98/End_of_universe.jpg

 

http://static.ddmcdn.com/gif/space-shape-4.jpg


This at least we can have a relatively small degree of uncertainty about: the Wilkinson Microwave Anisotropy Probe (WMAP) observations of the cosmic background radiation (CBR) have confirmed that the universe is flat (or very nearly so) with only a 0.5% margin of error.


Global Topology
This goes to the heart of the shape of the universe question and whether it has an “edge”, as it considers the entire universe, beyond that relatively small portion which we can observe locally within our cosmic horizon. Which of the three local curvature possibilities is actually the case imposes constraints on the possible global topology of the universe, and its extent: a spherical local geometry means a finite universe, while a flat or hyperbolic local geometry means an infinite universe.

The WMAP data indicate a slight possibility of positive local curvature (spherical local geometry, finite universe):
“According to the latest chart released in March [2006], the spots appear just fractionally larger than they would in flat space, implying that the universe has positive curvature like the surface of a sphere. If that's true, the ancient question would be all but answered: the universe does not stretch on forever. Instead, it curves around to form a finite universe. It would still be pretty big, of course, but limited, like the surface of the Earth; a closed but borderless cosmos.” [1]

So cosmologists are trying to analyse topologies that allow spacetime to wrap around on itself, to see if the effects they have on our CMB observations fit with the WMAP data. So far, there is no consensus on a ‘best fit’ topology, so the simple answer to the question “What is the shape of the universe?” is that we cannot be certain – yet.

Picture This – A 3-Torus
Visualising these ‘finite but unbounded’ candidates for universe topology can be very difficult, because we’ve evolved to perceive objects only in three extended and non-curving dimensions, and what we’re after here are shapes where all three dimensions curve back around on themselves. These can be described mathematically, but picturing them intuitively is very challenging to impossible.

One candidate topology, of which you may just be able to visualise a 3D map, is called the 3-torus. Let’s begin by thinking about a lower-dimensional analogy – a regular 2-torus, ie: the shape of a doughnut with a hole in the middle:

http://upload.wikimedia.org/wikipedia/commons/1/17/Torus.png

For a two-dimensional flatland being called Bob, whose whole universe was in the shape of the surface of a 2-torus, it doesn’t matter which direction or how far Bob travels, he’ll never encounter an “edge”, so his universe is finite but unbounded. Now let’s make a 1:1 scale map of Bob’s 2-torus universe, by making two incisions in an imaginary duplicate of it, and flatten it out. Incision 1 goes right around the tube of the 2-torus, so it uncurls into a cylinder, then incision 2 goes along the length of the cylinder, so it uncurls into a rectangle:

http://i22.photobucket.com/albums/b336/dalinian61/Quora/Torus-map.jpg  


Now any journey Bob takes along his non-incised 2-torus universe would be represented on our rectangular map like this:
• anytime Bob crosses the left-hand edge of the rectangle, he pops back on to the right-hand edge, and vice verse
• anytime he crosses the bottom edge of the rectangle, he pops back on to the top edge, and vice verse

But Alice is one of us – a three-dimensional being, whose whole universe is in the shape of the surface of a 3-torus (maybe). So let’s extend this map idea, by adding another dimension – morph the rectangular map into a square, extrude the square into a cube, and apply the same rule:
• anytime Alice crosses out of the front face of the cube, she pops back in by the rear face, and vice verse
• anytime she crosses out of the left face of the cube, she pops back in by the right face, and vice verse
• anytime she crosses out of the bottom face of the cube, she pops back in by the top face, and vice verse

So now we’re visualising a cubic map of Alice’s 3-torus universe, and I hope you can see that Alice’s journey experience is the same as Bob’s – it doesn’t matter which direction or how far Alice travels, she’ll never encounter an “edge”. (BTW, trying to visualise how to “curl-up” this cubic map into a 3-torus will very likely mess up your 3D-accustomed head: the front face curls around and is glued to the back face, the left face curls around and is glued to the right face, and the bottom face curls around and is glued to the top face, all in one seamless body.)

 

The Shape of Space Video
Here’s a short film from The Geometry Centre which gives an even better feel for the implications of living in a finite and unbounded 3-torus universe than the words and pictures above:



http://www.youtube.com/watch?v=Uzd484Mvm2k

So if we do indeed live in a finite universe, where local geometry exhibits slight but positive curvature, then the three extended dimensions with which we are familiar are curled up on the largest scale into a global topology which is finite and unbounded – and therefore “edgeless” – such as a 3-torus or something still more exotic.

Hope that’s broadened your understanding, and given you some pointers for further exploration,

Share and Enjoy, Peace-&-Love, Dalinian – ★ ☮ ♥ ꂨ ♻
——————————————————————————————————————
“The important thing is not to stop questioning; curiosity has its own reason for existing. One cannot help but be in awe when contemplating the mysteries of eternity, of life, of the marvellous structure of reality. It is enough if one tries merely to comprehend a little of the mystery every day.” ~ Albert Einstein, ‘LIFE’ magazine, 02 May 1955
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[1] From ‘Fold testament: what shape is the universe?’, by Stephen Battersby, in New Scientist, 07 Dec 2006
http://tribes.tribe.net/newscientist/thread/0472eab7-636a-4d1e-a721-49bbc2cf4a1f

 

 

 


 

 


What is the difference between an accretion disk and a protoplanetary disk?


   
 

 

  

 

 

 


 

Better Answer – not chosen by Asker

 

Hi Momentary997,

I thought I understood the difference, but in looking into the matter, I found I my understanding (which was the same as Loosey™’s) was wrong. And I believe I understand the source of your and Dennis’s confusion.

The trouble is that the word ‘accretion’ [1] in an astrophysical sense refers to BOTH:
A. the process by which planets form, and
B. the process by which protostars/white dwarves/neutron stars/black holes increase their mass.

In the case of stellar remnants – white dwarves, neutron stars and black holes – infalling matter forms an accretion disc [2] spiralling around the massive body, and the matter at the inner edge spirals inwards, adding mass to the stellar remnant – so only process B is present. This is also true for the supermassive black holes at the heart of quasars and other active galactic nuclei.

In the case of stellar formation, the circumstellar disk [3] surrounding the protostar [4] is undergoing BOTH process A AND process B – so matter from its inner region is spiralling inwards and adding mass to the protostar, at the same time as matter further out is accreting into planetesimals, planetoids, and planets.  So these protoplanetary disks are accretion disks in BOTH senses of the word.

That’s most likely an oversimplification, but I hope it clears up your confusion.

There’s a useful table at Scholarpedia which I think you may find illuminating:


» source – http://www.scholarpedia.org/article/Accretion_Discs   

Finally, it seems that the accretion disks that can form around neutron stars from post-supernova dusty debris can ALSO be protoplanetary disks. From observations of the magnetar 4U 0142+61 [5], we know that a post-supernova protoplanetary disk can form from a small fraction of the dusty debris left behind by the supernova. And we know from observations of pulsar PSR B1257+12 [6] that retinues of pulsar planets [7] can form from such post-supernova protoplanetary disks.


Thank you for prompting me to develop a greater understanding of accretion disks and a protoplanetary disks – I hope I’ve been able to broaden your understanding too, and given you some pointers for further exploration,

Share and Enjoy, Peace-&-Love, Dalinian – ★ ☮ ♥ ꂨ ♻
——————————————————————————————————————
“The important thing is not to stop questioning; curiosity has its own reason for existing. One cannot help but be in awe when contemplating the mysteries of eternity, of life, of the marvellous structure of reality. It is enough if one tries merely to comprehend a little of the mystery every day.” ~ Albert Einstein, ‘LIFE’ magazine, 02 May 1955
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[1] Accretion in astrophysics:
» http://en.wikipedia.org/wiki/Accretion_%28astrophysics%29

[2] Accretion disc:
» http://en.wikipedia.org/wiki/Accretion_disk
» http://www.scholarpedia.org/article/Accretion_Discs   

[3] Circumstellar disk:
» http://en.wikipedia.org/wiki/Circumstellar_disks   

[4] Protostar:
» http://en.wikipedia.org/wiki/Protostar   

[5] Magnetar 4U 0142+61:
» http://www.spitzer.caltech.edu/news/235-ssc2006-10-NASA-s-Spitzer-Finds-Hints-of-Planet-Birth-Around-Dead-Star

[6] Pulsar PSR B1257+12:
» http://en.wikipedia.org/wiki/PSR_B1257%2B12

[7] Pulsar planets:
» http://en.wikipedia.org/wiki/Pulsar_planet

 

 


 

What does Premordial polarized light discovered, mean?

 
 

 

 

A PRIMORDIAL POLARISED LIGHT DISCOVERY EXPLANATION – part 1 of 2

 

Hi Lex,

Always happy to help a curious and enquiring mind learn more about our glorious cosmos. The explanation could be kinda tricky if you’re fresh to cosmology, but I see from your Y!A history that you’re far from a fully noob enquirer, so here goes.


DOUBLE-DARK BIG BANG COSMOLOGY – OUR ‘STANDARD MODEL’
We now have a ‘Standard Model’ of Double Dark Big Bang Cosmology – and whenever physicists declare a ‘Standard Model’, it’s a sign that there’s an all but unanimous consensus among all well qualified experts in that field of science that this model has a very high concordance with reality (eg: the ‘Standard Model of Particle Physics’, at the opposite end of our universe’s distance scale). The dual ‘darks’ are the as-yet somewhat doubly mysterious dark matter (CDM – cold dark matter, holding galaxies together, et al) and dark energy (denoted by Lambda Λ – a cosmological constant, accelerating the expansion of the universe).

Formally, our model’s called the ‘Lambda-CDM Model’, and here’s a brief quote explaining why:

 

Lambda-CDM model
The ΛCDM or Lambda-CDM model is a parametrization of the Big Bang cosmological model in which the universe contains a cosmological constant, denoted by Lambda (Greek Λ), and cold dark matter (abbreviated CDM). It is frequently referred to as the standard model of Big Bang cosmology, since it is the simplest model that provides a reasonably good account of the following properties of the cosmos:

• the existence and structure of the cosmic microwave background
• the large-scale structure in the distribution of galaxies
• the abundances of hydrogen (including deuterium), helium, and lithium
• the accelerating expansion of the universe observed in the light from distant galaxies and supernovae

The model assumes that general relativity is the correct theory of gravity on cosmological scales. It emerged in the late 1990s as a concordance cosmology, after a period of time when disparate observed properties of the universe appeared mutually inconsistent, and there was no consensus on the makeup of the energy density of the universe.”
– source: Wikipedians, introducing the ‘Lambda-CDM model’ » http://en.wikipedia.org/wiki/Lambda-CDM_model



EVER BETTER EVIDENCE FOR COSMIC STRUCTURES
The reason for the strength of this consensus is that the more accurate our observations of relevant cosmological phenomena, such as the CBM (cosmic microwave background radiation » http://en.wikipedia.org/wiki/Cosmic_microwave_background ) observations by the COBE, WMAP, and Plank space observatories, the more closely they fit the predictions of the Double Dark Big Bang theory; for instance:


• ‘Big Bang data agree with the Double Dark theory’
– graphic illustration of just how well the WMAP’s 2010 data set (white error bars) fit the prediction of the Double Dark theory (blue wavy line), for the amount of structure on different angular scales in the temperature of the CMB.
– annotated illustration » http://new-universe.org/zenphoto/Chapter3/Illustrations/Abrams32.jpg.php
– reproduced as Fig 1, below

BTW, for a book-length popular science detailed introduction to the Double Dark Big Bang cosmology theory (which astrophysicist Joel Primack helped develop), I can personally recommend the book from which this illustration comes:
• ‘The New Universe and the Human Future: How a Shared Cosmology Could Transform the World’
– by wife-&-husband team Nancy Ellen Abrams and Joel R. Primack
– website » http://new-universe.org  

[cont’d in part 2, below…]

Fig 1, below: ‘Big Bang data agree with the Double Dark theory’, by Joel Primack

– source: » http://new-universe.org/zenphoto/Chapter3/Illustrations/Abrams32.jpg.php

 

 

 

A PRIMORDIAL POLARISED LIGHT DISCOVERY EXPLANATION – part 2 of 2


[…cont’d from part 1, above]


COSMOLOGICAL INFLATION
However, what occurred immediately before the universal timespan covered by our Double Dark Big Bang theory’s standard model – ie: the very first portions of the very first second of our universe’s existence – has been a matter of conjecture and hypothesis. Many astrophysicists are working on gathering evidence to confirm of falsify a hypothesis called ‘Cosmological Inflation’ – and here’s where the recent “Discovery: Gravity Waves Detected in Primordial Polarised Light”-type news article you mention comes in, as now also mentioned here:

 

Inflation (cosmology)
In physical cosmology, cosmological inflation is the expansion of space in the early universe at a rate much faster than the speed of light. The inflationary epoch lasted from 10^−36 seconds after the Big Bang to sometime between 10^−33 and 10^−32 seconds. Following the inflationary period, the universe continues to expand, but at a slower rate.

The term "inflation" is used to refer to the hypothesis that inflation occurred, to the theory of inflation, or to the inflationary epoch. The inflationary hypothesis was originally proposed in 1980 by American physicist Alan Guth, who named it "inflation". On 17 March 2014, astrophysicists of the BICEP2 collaboration announced the detection of inflationary gravitational waves in the B-mode power spectrum, apparently providing strong evidence for Guth's theory of inflation. [1][2][3][4][6]”
– source: Wikipedians, introducing ‘Inflation (cosmology)’ » http://en.wikipedia.org/wiki/Inflation_(cosmology)

 

So what’s that final sentence all about then, and what’s the big deal anyway? The theory of inflation makes predictions, one of which is that…
(A) just as Plank scale quantum fluctuations in the ‘Inflaton’ quantum field powering the inflation were expanded up to macroscopic energy density fluctuations by the inflationary process (which then went on to become density fluctuation seedings for dark matter coalescence and galaxy formation by gravitational collapse), then…
(B) so too should Plank scale quantum fluctuations in the ‘Gravitation’ quantum field give rise to ‘Gravity Waves’, which were predicted to be expanded up to macroscopic scale by the inflationary process.
– more info on ‘Gravity Waves’ » http://en.wikipedia.org/wiki/Gravitational_wave

The evidence for (A) is the minute temperature variations in the CBM, the accuracy with which they fit theoretical predictions (as noted in ‘EVER BETTER EVIDENCE FOR COSMIC STRUCTURES’, above) and their reflection in the ‘filaments, hubs, and voids’ large scale structure of our observable universe (plus what’s known as ‘E-mode polarisation’ in the CMB).

The BIG NEWS is, for the Very. First. Time. EVER! we seem to have detected evidence for (B), in what’s known as the curl patterns of ‘B-mode polarisation’ in the CMB – as the theory of inflation says we should!  In Fig 2 below, ‘BICEP2 B-mode Signal’ (from the BICEP2 astrophysicist team’s own website, called ‘BICEP2 2014 Results Release’ » http://bicepkeck.org ), it’s those red and blue swirling shading patterns that reflect the fingerprints of the gravity waves from which the B-mode polarisation curling pattens originated.


CONCLUSION
Well, that’s my best first go at an explanation. I get it (to my level-of-understanding satisfaction), but do you, I wonder Lex? If not… further online research may help – eg: check the five ‘announcement’ articles referenced in the Wikipedians’ introduction to ‘Inflation (cosmology)’  at the end of paragraph two » http://en.wikipedia.org/wiki/Inflation_(cosmology) (ie: currently [1][2][3][4][6] ).

Or maybe study jobbing astrophysicist and cosmology populariser Sean Carroll’s attempt at an explanation:
• ‘Gravitational Waves in the Cosmic Microwave Background’
– posted on March 16, 2014 by Sean Carroll
– blog post » http://www.preposterousuniverse.com/blog/about-sean/

Or maybe listen to astrophysicist and Physics Nobel Laureate Saul Perlmutter on the BICEP2 gravity waves news – recorded by an annoyingly amateurish student cameraperson (to whom, however, much gratitude is due for the access to Saul’s world class commentary) at the University of California, Berkeley, where Saul is a professor of physics:

 

• ‘Saul Perlmutter on BICEP2, Gravitational Waves, and Inflation Theory’
– lecture video, 30:51 » http://youtu.be/p3HzLYxpdCo

BTW, for me, this stuff Really Rings Bells usually jingled by appreciating modern conceptual art: an extraordinary artefact (eg: [ conceptual-artwork | Fig 2 below, ‘BICEP2 B-mode Signal’ ] ) becomes soooo much deeper, more significant, more meaningful, more beautiful, and more engaging, once I’ve grasped and internalised the originating [ artist | science-team ]’s concept that underpins the [ artwork | results-graph ]’s existence.


Fig 2, below: ‘BICEP2 B-mode Signal’
“Gravitational waves from inflation generate a faint but distinctive twisting pattern in the polarization of the CMB, known as a "curl" or B-mode pattern. For the density fluctuations that generate most of the polarization of the CMB, this part of the primordial pattern is exactly zero. Shown here is the actual B-mode pattern observed with the BICEP2 telescope, with the line segments showing the polarization from different spots on the sky. The red and blue shading shows the degree of clockwise and anti-clockwise twisting of this B-mode pattern.” – source » http://bicepkeck.org/visuals.html

 

 

 

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