The cosmic microwave background sky as seen by the Planck observatory.
Image: ESA and the Planck Collaboration
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The Planck space telescope has delivered the most detailed picture yet of the cosmic microwave background, the residual glow of the Big Bang.
Scientists unveiling the results from the €600 million European Space Agency (ESA) probe said that they shed fresh light on the first instants of our Universe’s birth. They also peg the age of the Universe at 13.81 billion years — slightly older than previously estimated.
“For cosmologists, this map is a goldmine of information,” says George Efstathiou, director of the Kavli Institute for Cosmology at the University of Cambridge, UK, one of Planck’s lead researchers.
Click here to read "Cocktail Party Physics" blogger Jennifer Ouellette's post with more background on these findings.
Planck’s results strongly support the idea that in the 10-32 seconds or so after the Big Bang, the Universe expanded at a staggering rate — a process dubbed inflation.
Inflation would explain why the Universe is so big, and why we cannot detect any curvature in the fabric of space (other than the tiny indentations caused by massive objects like black holes). The sudden ballooning of the primordial Universe also amplified quantum fluctuations into clumps of matter that later seeded the first stars, and eventually the straggly superclusters of galaxies that span hundreds of millions of light years.
The cosmic microwave background (CMB) radiation studied by Planck dates from about 380,000 years after the Big Bang, when the Universe had cooled to a few thousand degrees and neutral atoms of hydrogen and helium began to form from the seething mass of charged plasma. That allowed photons to travel unimpeded through space, in a pattern that carried the echoes of inflation. Those photons are still out there today, as a dim glow of microwaves with a temperature of just 2.7 K.
Since the CMB was first detected in 1965, the Cosmic Background Explorer (COBE) and the Wilkinson Microwave Anisotropy Probe (WMAP) have mapped the tiny temperature variations in the CMB with ever more precision. This has enabled cosmologists to work out when the Big Bang happened, estimate the amount of unseen dark matter in the cosmos, and measure the ‘dark energy’ that is accelerating the expansion of the Universe.
Planck, launched in 2009, is more than three times more sensitive than its predecessor WMAP. Its high-frequency microwave detector is cooled to just 0.1 degrees above absolute zero. That enables it to detect variations in the temperature of the CMB as small as a millionth of a degree.
These precision measurements show that the Universe is expanding slightly slower than estimated by WMAP. That rate, known as the Hubble constant, is 67.3 kilometers per second per megaparsec, which suggests that the Universe is about 80 million years older than WMAP had calculated.
It also means that dark energy makes up 68.3% of the energy density of the Universe, a slightly smaller proportion than WMAP had estimated. The contribution of dark matter swells from 22.7% to 26.8%, leaving normal matter making up less than 5%.
Planck also confirmed some oddities earlier noted by WMAP. The simplest models of inflation predict that fluctuations in the CMB should look the same all over the sky. But WMAP has found, and Planck confirmed, an asymmetry between opposite hemispheres of the sky, as well as a ‘cold spot’ that covers a large area. The asymmetry “defines a preferred direction in space, which is an extremely strange result,” says Efstathiou. This rules out some models of inflation, but does not undermine the idea itself, he adds. It does, however, raise tantalizing hints that there may yet be new physics to be discovered in Planck’s data.
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49 Comments
Add CommentI love science, and agree things seem to point to a big-bang c. 14 Byrs ago, but beyond that it seems to me like an enormous amount of speculation.
Reply | Report Abuse | Link to thisThe subtitle states:
Reply | Report Abuse | Link to this"The Planck space telescope's picture of the cosmic microwave background sheds fresh light on the first instants following the birth of the universe and suggests that it's about 80 million years older than previously thought."
The article states that the new estimate for the age of the universe is 13.81 billion years. The old esitmate was 13.772 ± 0.059 based on a published 2012 analysis of WMAP data. I don't do math, but that seems to be a difference of perhaps 40 million years, but still within the stated precision of the previous estimate. Please see
http://en.wikipedia.org/wiki/Age_of_the_universe
Both estimates are based on the standard Lambda-CDM concordance model of cosmology, which may be quite accurate but IMO is nonetheless fundamentally flawed...
One possible explanation for the newly verified dipole anisotropy in the CMB is that the structure of the cosmos has a fractal geometry and nature's hierarchy extends far beyond the observable universe.
Reply | Report Abuse | Link to thisUnlike the radical idea of a multiverse of 10^500 different universes with random properties, the discrete fractal paradigm proposes one unified physics for the entire cosmos. It is a new paradigm that is based on enlarging the symmetry properties of nature, rather than invoking ad hoc and thoroughly untestable speculations.
Robert L. Oldershaw
http://www3.amherst.edu/~rloldershaw
Discrete Scale Relativity/Fractal Cosmology
Here comes Ol' "It's Fractals All The Way Down!" Oldershaw.
Reply | Report Abuse | Link to thisThe CMB has "an asymmetry between opposite hemispheres of the sky."
Reply | Report Abuse | Link to thisSince it seems reasonable according to the Copernican principle that the observable Universe is not at the center of the entire Universe, should we expect to find symmetry in our observable Universe? Or maybe we are in an "privileged" location in the entire Universe, if we are close enough to the edge of the entire Universe as to skew the Hubble constant across our observable Universe (and therefore creating asymmetry in the CMB).
We know from special relativity that time is the fourth dimension hence the "size" of the universe is properly stated in units of space and time rather than space alone. Something that has been puzzling me is that if space is expanding then shouldn't time be expanding as well? Assume it is. Then if the universe is about 13.8 billion years in the past right now then exactly one billion years from today won't it be actually more than 14.8 billion years old because the past itself will have been receding away from us during that time? Similarly, one billion years ago the universe would have been not 12.8 years old then but something less than that. Could it even be possible that the discrepancy between current and past estimations of the age of the universe could derive in part not from measurement inaccuracy but because the age of the universe is actually changing at a different rate than what is measured by our clocks?
Reply | Report Abuse | Link to this"Inflation" seems so improbable.
Reply | Report Abuse | Link to thisCurrent theory holds that before the big bang there was no time. And then suddenly there was Time - exactly as we know and measure it today. Suppose instead that time is malleable, and that Time soon after the big bang was very different than time is today. Might that not make more sense than "inflation?" Has any work been done along these lines?
For what little it may be worth, a toy model ('A
Reply | Report Abuse | Link to thispoor thing, but mine own') involving black holes generating baby universes which I've cudgeled
for decades posits that the age of our observable universe is (in ascii symbols):
t_u ~ 2(hbar^2) / [G * Co * M_e * (M_p+e)^2] ,
where hbar is the reduced Planck constant (h/2pi);
G the Newtonian gravitational constant; Co the
speed of light in field-free space; M_e the electron mass; and M_p+e is the sum of the proton mass
and the electron mass.
Oddly enough, using the current Codata values, this
yields
4.357409…*10^17 seconds,
or
13.80779…*10^9 years.
It's obvious that if this is at least roughly true, something on the right hand side of the relation
must change over cosmic time, if the universe's
age or equivalently, its Hubble radius is to
increase over time (a reasonable assumption :-)).
An interesting conundrum.
Re: “Planck’s results strongly support the idea that in the 10^-32 seconds or so after the Big Bang, the Universe expanded at a staggering rate—a process dubbed inflation.”
Reply | Report Abuse | Link to this“I cannot deny a feeling of unreality in writing about the first three minutes as if we really know what we are talking about.”
[Prof. Steven Weinberg. 1977. The first three minutes: A modern view of the origin of the universe. Basic Books, p. 9]
Reply | Report Abuse | Link to thisWell, it may be fractals all the way down, and fractals all the way up too, with no top or bottom.
Never hurts to think anew.
Special relativity has been refuted, The CMB Radiation has
Reply | Report Abuse | Link to thisindicated that there is an aether drift in the direction LEO. Smoot called THE NEW AETHER DRIFT! Why is this factum ignored by mainstream physics.
Hartwig Thim
Imagine a “Maxwell Demon” of infinitesimal size deep in the interior of a type-II supernova event.
Reply | Report Abuse | Link to thisSurveying his observable environment of about 10^-18 cubic centimeters, he draws the following conclusions.
1. There is global expansion as he can see from the velocities of the gigantic particles.
2. Superimposed upon this global expansion are random velocities of about 700 km/sec that he calls “peculiar velocities” and indicate some unexplained very high-energy and chaotic phenomena.
3. The distribution of the gigantic particles looks very homogeneous, at least statistically speaking, but there is a small dipole anisotropy, i.e., slightly more particles and slightly higher temperatures in one direction and slightly lower values in the opposite direction.
We then move “Maxwell” by about 10^15 centimeters to a location far outside of the supernova event. With mouth and eyes wide open, he utters two 4-letter words. The first is “holy” and the second begins with “S”.
Robert L. Oldershaw
http://www3.amherst.edu/~rloldershaw
Discrete Scale Relativity/Fractal Cosmology
Is there a mathematical basis for universes with different properties? I recognize that this stuff isn’t necessarily intuitive, but it seems more reasonable that they would all work the same way.
Reply | Report Abuse | Link to thisInflation and dark matter seem to be the cosmic fudge factors which cosmologists have introduced into their big bang hypothesis to make it all hang together.
Reply | Report Abuse | Link to thisAlthough they can see cosmic background microwave radiation in most directions, except for some big holes in the sky, it seems these are used to somehow make it all seem even more plausible.
I don't really think the cosmologists know what they are talking about.
If there was any evidence of inflation beyond just trying to explain what is seen with radio telescopes (the cosmic background radiation) and deep sky observation with telescopes such as the Hubble Space Telescope, then I would be much more willing to buy it, but it seems they are just putting fudge factors (inflation, dark matter, and dark energy) into hypothetical equations which don't have any basis in observation.
Possibly there was a different substrate, what ever dark matter is, I personally think it was super-cold, sub-absolute zero medium, an aether if you will, which has different physical qualities than the know universe, perhaps made up of tachyons, or faster than light particles, with wave forms, which through interference, create waves and crests, cancellation and summation, so eventually wave form crests may exceed the containment limits of the medium, perhaps with wave particles at crests gaining enough energy to exceed the parameters of the pre-existing universe or medium, and emerging into our present universe.
The wave speed in the "dark matter" medium exceeding relativistic speed, due to being composed of tachyons, and the present universe emerging or popping out of the background medium practically simultaneously and continuing to emerge, and variation on the continuous state universe with a beginning, and possibly an end if all the dark matter eventually emerges into our present universe.
Inflation is really a problem, and unless they can explain it, I think it is just a big bang fudge factor and should not be taken any more seriously than any other hypothesis and in fact less so since relativistic physics defies it.
That is interesting. However, at very large scales, some symmetries might be still observable over large regions of the universe, while other symmetries my be observable in other regions - without violating the the general precept that our view of the universe is not in any way privileged.
Reply | Report Abuse | Link to thisMoreover, while we can't (as in the Ptolemaic system had) presume that we are in a privileged central position within the universe, I suspect that, while spacetime expands omnidirectionally around any observer, as does the spacetime in a radially expanding sphere, there still may be a special geometrically central origin of expansion (cold spot?) that might be detectable from many locations within the universe.
The Plank observational data indicates a very large scale anomalous symmetry in the distribution of ancient microwave emissions, capped by a seemingly related very large scale cold spot. Please see
http://spaceinimages.esa.int/Images/2013/03/Planck_enhanced_anomalies
The asymmetry and cold spot briefly mentioned in this news report do not seem to do justice to the report in the ESA announcement:
"One of the most surprising findings is that the fluctuations in the CMB temperatures at large angular scales do not match those predicted by the standard model – their signals are not as strong as expected from the smaller scale structure revealed by Planck.
"Another is an asymmetry in the average temperatures on opposite hemispheres of the sky. This runs counter to the prediction made by the standard model that the Universe should be broadly similar in any direction we look.
Furthermore, a cold spot extends over a patch of sky that is much larger than expected.
"The asymmetry and the cold spot had already been hinted at with Planck’s predecessor, NASA’s WMAP mission, but were largely ignored because of lingering doubts about their cosmic origin.
""The fact that Planck has made such a significant detection of these anomalies erases any doubts about their reality; it can no longer be said that they are artefacts of the measurements. They are real and we have to look for a credible explanation," says Paolo Natoli of the University of Ferrara, Italy."
Please see http://www.esa.int/Our_Activities/Space_Science/Planck/Planck_reveals_an_almost_perfect_Universe
and http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=51551
(continued)
Reply | Report Abuse | Link to thisThat the current standard Lambda-Cold Dark Matter model of cosmology produces results that can be well fit to current, exceedingly complex interpretations of observations does not preclude fundamental misconceptions - as demonstrated for more than a millennium by the Ptolemaic model of the cosmos.
http://en.wikipedia.org/wiki/Copernican_principle
"In physical cosmology, the Copernican principle, named after Nicolaus Copernicus, states that the Earth is not in a central, specially favored position. More recently, the principle has been generalized to the relativistic concept that humans are not privileged observers of the universe."
Time is the pulse of the universe.
Reply | Report Abuse | Link to thisThe pulse is the Planck constant.
The universe is being created & destroyed every Planck constant.(refer to Smolin's theory on universe evolution)
The pulse is wave / particle duality
Consciousness is part of the physical fabric of the universe.
The vacuum of space is indistinguishable from the vacuum of consciousness.
We do not live in a space : time continuum but a space : consciousness continuum.
Space is the particle function. Consciousness the wave.
Material and immaterial are human concepts. An atom of matter is 99.999999999999...% space.
Matter is energized space.
A human thought is one example of energized consciousness
Space and consciousness are two sides of the same coin.
The light of consciousness is the consciousness of light.
The consciousness of space is the space of consciousness.
The light of space is the space of light.
Photons traveling at the speed of light by defintion exist outside of time, are not in time.
Non-locality is a property of the universe
If a photon had ego consciousness, it would experience time as we do: a constant state of NOW.
Intelligent design is a PROPERTY of the universe.
The universe has memory.
There is no God.
There is no after life.
There is the Great IS, that was always before and will always be
Great comment! Thank you. Standard model and big bang are
Reply | Report Abuse | Link to thisalso nonsense including special relativity. Einstein had messed up physics for 100 years. Boscovich knew it much better, but he was ignored.
"... it seems they are just putting fudge factors (inflation, dark matter, and dark energy) into hypothetical equations which don't have any basis in observation."
Reply | Report Abuse | Link to thisIn an admittedly backhanded defense of physicists, your accusations must be modified for accuracy. More correctly, astrophysicists and cosmologists have invented fudge factors to 'magically' resolve discrepancies between observations and the predictions of theory, at least as applied. There is no physical evidence for the existence these compensatory factors except for the discrepancies between observations and applied theory.
The most straightforward example is the perceived discrepancy between observation of spiral galaxy rotational dynamics and expectations based solely on Keplerian rotation curves.
Keplerian rotation curves simply plot rotational velocity as a function of radial distance, since observations of the Solar system indicated that orbitals' velocities diminish solely as a function of their separation distance from the Sun which, most critically, contains 99.86% of total system mass.
In the specific distribution of mass and therefore related gravitational effects in the highly centralize-mass Solar system, the diminishment of gravitational effects almost entirely as a function of radial distance naturally follows the laws of inverse-squares.
However, applying this conveniently simple two-body relation to the large scale, highly distributed mass configurations of compound spiral galaxy structures produced a discrepancy, since up to hundreds of billions of discrete, relatively proximal objects of mass each gravitationally interact with one another rather than any central, dominant mass like the Solar system.
Some unseen source of galactic mass distributed at much radii larger than observed galactic objects could fit the characteristic flat rotation curve of observed self-interacting peripheral objects within the simplistic Keplerian model of rotational dynamics.
Alternatively, it was noticed that the apparent discrepancy occurred only when the established, simplistic methods of gravitational evaluation were applied to large scale (complex, compound) masses. As a result, modified theories of gravity were proposed that included scale dependent fudge factors in their equations.
(continued)
Reply | Report Abuse | Link to thisApplying Occam's razor, the simplest explanation is that when overly simplistic methods of approximating gravitational effects are applied to increasingly complex, compound masses, they introduce increasing errors in their resulting predictions of gravitational effects. It is simply the increasing error of improperly applied methods of gravitational evaluation that produce the discrepancies with observations.
Other examples of gravitational evaluations producing inferences of dark matter are likely the result of similar errors, but they are much more difficult to assess and explain.
As for dark energy, the method of evaluation producing the observational discrepancy is the estimation of distance, derived from then current standard cosmological models, based on redshift. Again, it's very difficult to identify specific errors in cosmological models, but there are certainly other potential sources of error than a temporally varying rate of expansion.
As reported in the article there are also unresolved discrepancies between CMB observations and the current Lambda-CDM standard model of cosmology. Hopefully the model will be reevaluated rather than conjuring up some new 'dark', unphysical compensatory element...
BTW, links to preprint drafts of more than 30 related papers submitted to journals for publication can be found at
Reply | Report Abuse | Link to thishttp://www.sciops.esa.int/index.php?project=PLANCK&page=Planck_Published_Papers
You state "Current theory holds that before the big bang there was no time." First time I've heard that proposed as being accepted!
Reply | Report Abuse | Link to thisOther equally plausible scenarios posit a cycling cosmos, collapsing and expanding repeatedly.
Hello Syzygy...,
Reply | Report Abuse | Link to thisMy understanding is that string theorists found that their pseudo-theory had roughly 10^500 different solutions, which is a bit of a problem given Occam's razor.
As a way to make this bizarre result more acceptable and save string theory from the trashbin of history (at least temporarily) they floated the idea that each solution represented a different "universe" in the "multiverse", each with different physics.
Such is the sorry state of theoretical physics today, when such a bizarre and empirically unmotivated just-so story can be treated as serious science.
Robert L. Oldershaw
http://www3.amherst.edu/~rloldershaw
Discrete Scale Relativity/Fractal Cosmology
jtdwyer,
Reply | Report Abuse | Link to thisAre you saying that Keplerian motion does not work for galaxies because of the highly distributed mass configurations of galaxies?
You are somewhat correct, but that idea does not refute the idea of dark matter. What you seem to be saying has been known for almost as long as it has been known that Andromeda was not part of the Milky Way (maybe longer).
Maybe I'm misunderstanding exactly what you are claiming, so I would have to see the mathematics of your theory. It sounds similar to what Jan Oort did in 1932 when determining the differential rotation of the Milky Way by observing stars near the Sun. Oort considered the angular momentum gradient and the shearing motion in the galactic disk. Oort was the first to discover the Milky Way should have more mass than the differential rotational velocities suggested.
http://en.wikipedia.org/wiki/Oort_constants
Very interesting - thanks! It seems that Oort had a good understanding of galactic dynamics. However, see
Reply | Report Abuse | Link to thishttp://en.wikipedia.org/wiki/Dark_matter#Galaxy_rotation_curves
"... In the late 1960s and early 1970s, Vera Rubin[...] worked with a new sensitive spectrograph that could measure the velocity curve of edge-on spiral galaxies to a greater degree of accuracy than had ever before been achieved. Together with fellow staff-member Kent Ford, Rubin announced at a 1975 meeting of the American Astronomical Society the discovery that most stars in spiral galaxies orbit at roughly the same speed, which implied that the mass densities of the galaxies were uniform well beyond the regions containing most of the stars (the galactic bulge), a result independently found in 1978. An influential paper presented Rubin's results in 1980. Rubin's observations and calculations showed that most galaxies must contain about six times as much "dark" mass as can be accounted for by the visible stars. Eventually other astronomers began to corroborate her work and it soon became well-established that most
galaxies were dominated by "dark matter"..."
The referenced "influential paper" by Rubin et al. in 1980 states in Section VIII on page 485, "DISCUSSION AND CONCLUSIONS":
"1. Most galaxies exhibit rising rotational velocities at the last measured velocity; only for the very largest galaxies are the rotation curves flat. Thus the smallest Sc’s (i.e., lowest luminosity) exhibit the same lack of a Keplerian velocity decrease at large R as do the high-luminosity spirals. This form for the rotation curves implies that the mass is not centrally condensed, but that significant mass is located at large R. The integral mass is increasing at least as fast as R. The mass is not converging to a limiting mass at the edge of the optical image. The conclusion is inescapable that non-luminous matter exists beyond the optical galaxy."
http://dx.doi.org/10.1086/158003
As I understand, there was never any formal analysis indicating that galactic disc objects should comply with Keplerian rotation curves, but that alone was the basis for proposing dark matter.
In a brief, informal essay I describe a number of references, including two that properly describe observed galactic rotation curves without dark matter or modified gravity - one using relativistic dynamics; one using Newtonian dynamics.
http://fqxi.org/data/essay-contest-files/Dwyer_FQXi_2012__Questionin_1.pdf
For DM halo constraints http://news.sciencemag.org/sciencenow/2013/01/has-the-milky-lost-weight.html
"Are you saying that Keplerian motion does not work for galaxies because of the highly distributed mass configurations of galaxies?"
Reply | Report Abuse | Link to thisYes - the presence of galactic dark matter is inferred by the flat rotation curves of spiral galaxies. I don't do math, but as I understand, dark matter configurations are evaluated based on their ability to fit the observed galactic rotation curves to Keplerian dynamics. If you consider Kepler's equations, I think you'll find that they only represent two-body relations...
The last reference in the preceding comment finds, based on the Keplerian compliant orbits of stellar halo stars, each in effect independently orbiting the distant MW bulge and disk - just like planets in the Solar system, that 4/5 of the MW's total mass (within 150 kpc) is actually contained within a radius of 50 kpc. This is not consistent with an enormous dark matter halo that might explain the rotation curve of MW disk objects.
Also, why would stellar halo objects comply with Keplerian dynamics while disk objects do not? IMO, it is because halo object independently orbit a central mass, while loosely bound disk objects more properly rotate (similarly to a fluid, as Oort seemed to notice). Again, see the referenced papers that model galaxy rotational dynamics without DM.
We are not in a privileged position, but not for the reason you cite. There is no center of the universe.
Reply | Report Abuse | Link to thisConsult the ubiquitous 2D representation of the 3D universe, where the observable part is the surface of an expanding sphere (balloon) and our POV is just a point on the surface. In this model, the sphere expands and the points get farther apart, but there is no center to the expansion from any POV on the 2D surface.
As I understand, in the common inflating balloon analogy our perspective may be limited to the surface of the balloon, but in fact an expanding balloon does have a discrete geometric point of origin for its global expansion.
Reply | Report Abuse | Link to thisEven within an enormous balloon, embedded objects suspended within some expanding media would all appear to be receding away from all internal observers.
However, to an imaginary external observer, the surface of the balloon could actually be seen to be radially expanding away from its geometric center-point...
jtdwyer,
Reply | Report Abuse | Link to thisYou would really have to figure out the mathematics. I believe I am following you -- I had the same thought back in the 1990s. I just believe it is so simple that it would be scandalous if true. It would be the greatest blunder in the history of science.
Here's another paper of someone that appears to be claiming the same thing:
http://arxiv.org/ftp/astro-ph/papers/0006/0006140.pdf
Here's some more early work by Subrahmanyan Chandrasekhar in 1943 that I would believe most astrophysicists would know (and it should apply to your concept):
http://en.wikipedia.org/wiki/Dynamical_friction
Here's a some simple mathematics but for a spherical galaxy or in the galactic bulge:
http://www.kcvs.ca/martin/astro/course/lectures/winter/rot1.htm
Also, could using Kepler laws just be a application of the Shell theorem:
http://en.wikipedia.org/wiki/Shell_theorem
metamorphmuses,
Reply | Report Abuse | Link to thisThanks for your reply. Sorry, my last sentence was meant to be a question.
By studying the CMB cosmologists are attempting to determine if the observable Universe is homogeneous, isotropic, and flat. Do you not think (or at least try to imagine) that the results from the Planck telescope bring some of that into question? Are you claiming that the Universe is certainly homogeneous, isotropic, flat and infinite?
In a perfectly flat universe, the universe must be infinite for there to be no center. We can not absolutely conclude that the entire Universe is much larger than the observable Universe.
I was just raising the point that if the Hubble constant is asymmetric across the observable Universe, then that might mean that the observable Universe is close to the edge of the entire Universe. Are you saying asymmetric expansion would not possibly mean that?
The GR effects of gravity/inertia on space-time, need to be explicitly considered in spatial/temporal estimates of the (asymmetric ?) configuration of the observed universe.
Reply | Report Abuse | Link to this@jtdwyer - "As I understand, in the common inflating balloon analogy our perspective may be limited to the surface of the balloon, but in fact an expanding balloon does have a discrete geometric point of origin for its global expansion."
Reply | Report Abuse | Link to thisRight, the point of origin does not lie on the surface, and yet only the surface is observable to us, being that (in this model) we're 2D beings, our observation confined to the surface.
@Cramer - "Do you not think (or at least try to imagine) that the results from the Planck telescope bring some of that into question? Are you claiming that the Universe is certainly homogeneous, isotropic, flat and infinite?"
I don't have a scientific answer to that. But I suspect any deviations from isotropy are local rather than truly cosmic, to the extent that the dimensions of spacetime we have access to do not contain a central point, relative to the expansion of the universe. I doubt that the universe is flat, it is almost certainly expanding. Based on my knowledge of astronomy from my university days, the universe's geometry is then supposed to be analogous to a saddle (hyperbolic) [http://en.wikipedia.org/wiki/Shape_of_the_universe].
"Are you saying asymmetric expansion would not possibly mean that?" Again, I am not an astronomer or cosmologist, so I cannot answer that rigorously. I have to simply point you to the textbook answer, which is roughly represented in the Wikipedia article I link to above. In a hyperbolic paraboloid model, there is still no absolute center on the surface of the projection any more than there is on the surface of a spherical projection.
Frankly, this is about the extent of my knowledge in this area. I cannot give you a serious mathematical/topological account. But I do understand that expanding any of the three topological models (spherical, flat, and hyperbolic) does not require reference to a center point on the surface of the projections.
metamorphmuses,
Reply | Report Abuse | Link to thisI am only referring to what might be possible for what's outside our observable Universe. Regarding my reference to an edge, this would only apply to some type of multiverse theory.
meta said, "I doubt that the universe is flat, it is almost certainly expanding."
I believe the two are not mutually exclusive. Any shape (spherical, hyperbolic, or flat) can expand. Did you mean an accelerating expansion? However, I do like the idea that the curvature of space has to do both with expansion and contraction (i.e. gravity) of space; but I haven't seen any reference of this idea by a cosmologist. If you know of a reference, I would appreciate seeing it.
meta said, "But I do understand that expanding any of the three topological models (spherical, flat, and hyperbolic) does not require reference to a center point on the surface of the projections."
I agree that the Universe is not expanding from a center point (I never claimed otherwise). However, that is much different than the Universe not having a center point. If a finite piece of rubber is stretched, it is expanding from all points, but the finite piece of rubber does have a center point. Therefore both flat and hyperbolic universes that are finite can have a center (multiverse possibility).
meta said, "...the universe's geometry is then supposed to be analogous to a saddle (hyperbolic)."
Both WMAP and Planck results suggest that the observable Universe is flat.
Does not the simple one cycle S curve of brightness spanning the entire sky support a theory that the big bang originated from a single primordial structure of finite dimensions? The background radiation is clearly not isotropic. If the shape of the polarization correlates with the brightness it would seem to add credence to a simple primordial structure.
Reply | Report Abuse | Link to this
Reply | Report Abuse | Link to thisFor centuries many have assumed that the observable universe (u) was essentially equivalent to the whole Universe (U).
A minority of natural philosophers, notably Spinoza and
Kant, have strenuously countered that the u = U assumption is very dubious, is empirically unmotivated, and indicates a regrettable anthropocentric bias.
They argued that if one used the observable universe as a
guide for modeling the Universe, then an infinite hierarchical model was a much more scientific assumption.
Since neither Spinoza nor Kant knew that stars were
hierarchically organized into vast "island universes" called galaxies, the discovery of galaxies in the 20th century was an impressive vindication of their hierarchical paradigm.
Why do many still assume that u = U? Well, perhaps those who do not learn the lessons of history are condemned to repeat past mistakes.
Robert L. Oldershaw
http://www3.amherst.edu/~rloldershaw
Discrete Scale Relativity/Fractal Cosmology
I am not very scientific, however, saying that the Universe is billions of years old I assume is based on how we measure time here on earth. But doesn't time stand still in space, for instance if the universe exploded "at the speed of light." Then what appears to be billions of years in how we measure time, may have been a fraction of that time in space...if "time" at all. Perhaps time did not exist under the circumstances and we experience it here on earth. What say all of you? Thanks.
Reply | Report Abuse | Link to thisAngegirl2u,
Reply | Report Abuse | Link to thisWecome to the club of non-scientists. It seems to me, cosmic expansion is a requirement for the alleged billions of years for the age of the universe (i.e., the measurement of distance in “light years”). It further seems to me, a
“big-bang” (in addition to the tweak of “inflation”) is a requirement for cosmic expansion. If my understanding is correct, there is no instance in human experience in which an explosion has generated order. Yet, we're expected to believe (for it is a faith commitment) that a gigantic explosion generated the phenomenal order observed in the cosmos. The notion leaves me perplexed.
Angegirl2u, Bill_Crofut,
Reply | Report Abuse | Link to thisThere was no explosion. Matter was and is not flying apart THROUGH space as it does when a bomb explodes. Space itself is expanding.
For time dilation to occur due to relative velocity, observers have to be in different inertial reference frames in space. Space expanding does not create another inertial system (no bomb exploding).
Bill Crofut,
There is no faith required for the expansion of space (Big Bang). I could list the evidence, such as galaxies that are further away are receding away from us at a greater speed than galaxies closer to us, etc. You need to study the evidence. You can start with "Observation Evidence" for the Big Bang:
http://en.wikipedia.org/wiki/Big_Bang#Observational_evidence
Cramer,
Reply | Report Abuse | Link to thisRe: “There was no explosion.”
“In the beginning there was an explosion. Not an explosion like those familiar on earth, starting from a definite center and spreading out to engulf more and more of the circumambient air, but an explosion which occurred simultaneously everywhere, filling all space from the beginning, with every particle of matter rushing apart from every other particle...[I]t appears that the universe is undergoing some sort of explosion in which every galaxy is rushing away from every other galaxy.”
[Prof. Steven Weinberg. 1977. The first three minutes: A modern view of the origin of the universe. Basic Books, pp. 5, 21]
Catholic apologist Arnold Lunn put the issue in perspective as well as anyone in my research experience:
“If, on the other hand, the word “universe” means, as it should, the sum total of reality, it is surely absurd to talk about space expanding.”
[1935. The Aquinate proofs. In: Science and the Supernatural. Sheed and Ward, Inc., p. 261]
Where is the sum total of reality going to "go" to expand?
It seems to me, studying the “evidence” is a bit premature.
Bill_Crofut,
Reply | Report Abuse | Link to thisThe evidence for space expanding is not premature. You seemed not to have studied the evidence. You made no refutation of the evidence I gave you:
http://en.wikipedia.org/wiki/Big_Bang#Observational_evidence
You seem to already have your answer and are attempting to look for evidence that confirms your answer (i.e. space is not expanding).
The two quotes you provided are not evidence that space is not expanding. Steven Weinberg in 1977 said nothing different from what I said. He simply used the word explosion to describe the expansion of space -- simple use of figurative language (semantics).
In 1935, there were still scientists that believed Hubble was wrong. Einstein once believed in a static universe. It was Hubble's research that caused Einstein to change his mind.
Besides Arnold Lund's quote being from 1935, his quote also pertains to semantics. He defined "universe" as the "sum total of reality." Nobody knows if the Big Bang created everything. I don't believe many scientists are claiming that to be settled science (as is the expansion of space). There are many theories.
You asked, "Where is the sum total of reality going to "go" to expand?"
Nobody knows. First, you are making the assumption of the Big Bang being the "sum total." Our "Big Bang" Universe can simply be expanding into another universe (such as in a multiverse theory). Or it could be expanding into nothing (think General Relativity). Or infinity could be expanding into greater infinity. Who knows. That's why scientists are spending significant resources studying the CMB.
If you are serious, you would go through each piece of evidence. And you need to refute each piece. For example, you would have to give an alternative explanation of why more distance galaxies are speeding away from us faster than closer galaxies (outside our cluster). Or prove the observational evidence is in error (i.e. galaxies further away are not actually speeding away faster).
Bill_Crofut,
Reply | Report Abuse | Link to thisCould you provide the entire quote by Arnold Lunn? I tried searching the internet and google books for it (I did find you using the same quote on 10/04/12 on SciAm).
Lunn writes, "If, on the other hand, the word "universe" means..." On the other hand of what?
See how that works? I like understanding the ideas of others (even if those ideas are from 1935 by a skier without much scientific expertise writing about the supernatural). You seem to close yourself off from the ideas of people (i.e. present-day scientists) who do not agree with you. At least that's what can be interpreted when you appear to ignore what everyone else says (since you never address why further away galaxies are speeding away at faster rates).
Cramer,
Reply | Report Abuse | Link to thisRe: "If you are serious, you would go through each piece of evidence. And you need to refute each piece. For example, you would have to give an alternative explanation of why more distance galaxies are speeding away from us faster than closer galaxies (outside our cluster)."
Ok, allow me to attempt a refutation of one piece of "evidence."
If my understanding is correct, the only "evidence" for galactic recession is red shift interpreted as Doppler effect; quasars are the most distant light sources in the cosmos based on red shift.
Astronomer Halton Arp has photographic evidence of high-red-shift quasars luminously linked to low-red-shift galaxies. That would certainly seem to indicate that red shift cannot be interpreted as Doppler shift, at least in some cases. Red shift, then, would seem to be inappropriately used as a universal (no pun intended) indicator of galactic recession. Since it would seem to be misapplied in some cases, would not common sense dictate questioning the assertion in other cases as well?
It seems to me the charge you leveled against me, "You seem to already have your answer and are attempting to look for evidence that confirms your answer..." is a charge that looks back, but not on my authority:
"...Hubble estimated the distance to 18 galaxies from the apparent luminosity of their brightest stars, and compared these distances with the galaxies’ respective velocities determined spectroscopically from their Doppler shifts. His conclusion was that there is a “roughly linear relation” (i.e., simple proportionality) between velocities and distances. Actually, a look at Hubble’s data leaves me perplexed how he could reach such a conclusion—galactic velocities seem almost uncorrelated with their distance, with only a mild tendency for velocity to increase with distance. In fact, we would not expect any neat relation of proportionality between velocity and distance for these 18 galaxies—they are all much too close, none being farther than the Virgo cluster. It is difficult to avoid the conclusion that, relying either on the simple arguments sketched above or the related theoretical developments to be discussed below, Hubble knew the answer he wanted to get."
[Prof. Steven Weinberg. 1977. The first three minutes: A modern view of the origin of the universe. Basic Books, pp. 25-26]
Regarding the Lunn quote, unfortunately, what’s already been quoted is all there is in my possession. However, you may have also noted, my preference for using quotes from those who disagree with me (Lunn being one of the few exceptions) as evidenced by the quote above.
Bill_Crofut,
Reply | Report Abuse | Link to thisWhy not study what has been found in the last 20 years? You are looking at what people said and did 40 years ago (Arp) to 80 years ago (Hubble). The lastest quotes you have are from Steven Weinberg in 1977. And I agree with everything Prof. Weinberg said. I am also "perplexed" of how Edwin Hubble made his conclusion and it is likely "he knew the answer he wanted to get."
Hubble only looked at galaxies less than 100 million light years in distance. We now look at galaxies billions of light years away.
Same goes with Halton Arp as with Edwin Hubble. The only difference is that with better technology and more methods we found Hubble to be correct and Arp to be wrong. The high red-shift quasars have been found to be in high red-shift galaxies. The redshift quantization hypothesis favored by Halton Arp results from phenomena that are now well understood. It does not explain cosmological redshift.
http://en.wikipedia.org/wiki/Redshift_quantization#Evaluation_and_criticism
Your "misapplied in some cases" therefore misapplied in other cases (or all cases) is the hasty generalization fallacy. But it doesn't matter anyway, because there was no "misapplication" -- Arp was wrong (no high redshift quasars linked to low redshift galaxies).
Also (FYI), the Doppler effect has little to do with evidence for galactic recession. Evidence is from cosmological redshift, not Doppler redshift.
http://en.wikipedia.org/wiki/Redshift#Expansion_of_space
I love to read the comments from the amatuer physicists and am impressed that so many sound like they really know what they are talking about. Keep it up guys, and gals. Since my age finally caught up with my I.Q. (86), I look forward to many more years of learning. Thanks.
Reply | Report Abuse | Link to thisTom
Cramer,
Reply | Report Abuse | Link to thisRe: "Why not study what has been found in the last 20 years?"
http://iopscience.iop.org/0004-637X/591/2/690/fulltext/16841.text.html
and
http://www.thunderbolts.info/tpod/2004/arch/041001quasar-galaxy.htm
Re: "...with better technology and more methods we found Hubble to be correct and Arp to be wrong."
http://www.haltonarp.com/illustrations/arphf2
http://www.haltonarp.com/illustrations/arphf6
and
http://www.haltonarp.com/illustrations/arphf8
Re: "Your "misapplied in some cases" therefore misapplied in other cases (or all cases) is the hasty generalization fallacy."
You obviously did not read my comment carefully:
Since it would seem to be misapplied in some cases, would not common sense dictate questioning the assertion in other cases as well?
It's a specific suggestion, not a hasty generalization. Is not science supposed to be about questioning?
Hi Tom,
Reply | Report Abuse | Link to thisWelcome to the club; my age finally caught up with my I.Q. as well (71). Since my lack of knowledge is manifest, it's my practice to quote those whose knowledge is accepted by the members of the science community (i.e., Prof. Steven Weinberg). It's my hope to keep learning up to the point of being laid in my casket.
Bill_Crofut,
Reply | Report Abuse | Link to thisYou are correct. I did not read your comment carefully.
You asked, "Since it would seem to be misapplied in some cases, would not common sense dictate questioning the assertion in other cases as well?"
I'll change my answer to yes. However, in this case, questioning the assertion of the other cases was already done in the 1960s and 1970s.
When Halton Arp and a few others in the fringe continue to question the assertion in the face of overwhelming evidence, that is called quackery.
We have now observed almost 50,000 quasars; and we have a small handful that appear to be ejected from low-redshift galaxies. I wish anomalies didn't occur in life; however, with time most anomalies are usually reconciled (and since I am not an astronomer, I am not even sure they are anomalies -- maybe they have all been explained).
Here's one study I found from 2005:
http://adsabs.harvard.edu/abs/2005ApJ...633...41T
Cramer,
Reply | Report Abuse | Link to thisWelcome to the club of non-astronomers.
If my understanding is correct, Arp was >>>>>RELEGATED<<<<< to the fringe because his photographic evidence contradicted the reigning paradigm. Since he refused to back down from that evidence, he has been banned from using a telescope in the U.S. by those in the hierarchy of the astronomical community who were unable to "explain away" his evidence.
Somehow, that action doesn't seem to me to constitute the scientific method.
Re: http://adsabs.harvard.edu/abs/2005ApJ...633...41T
The charts and graphs in the paper may be interesting to some, but far more interesting for me would be visual confirmation of the QSO's included in the study (such Arp has provided on his website; see url's in comment 45).
Dark energy and inflation are both very ad hoc hypotheses. Perhaps one should first best explore pre-Big Bang patterns ad the structure of space and time, as I am suggesting since 1996.
Reply | Report Abuse | Link to thisFermions (proton, neutron, electron, muon, neutrinos, quarks...) "see" a spinorial space time where a 360 degrees rotation changes the sign of the wave function. Using a spinorial space-time in Cosmology, one naturally gets a "geometric" value of the ratio between relative speeds and distances at cosmic scale, H, equal to the inverse of the age of the Universe, t. From Planck data and analyses, the value of H x t is found to be around 0.96 quite close to the "geometric" value of 1 I obtain.
Thus, my conjecture is that the product H x t tends asymptotically to 1 in our Universe as the cosmic time t goes to infinity, and that the observed cosmic acceleration is just a fluctuation due to the reaction of standard matter to the pre-existing geometric expansion of the Universe. As the matter density decreases, such a reaction gets weaker and the relation between H and t tends to the geometric law H x t = 1. This natural evolution accelerates the observed expansion.
Such a geometric expansion of the Universe may reflect a deep equilibrium between geometry and the most fundamental structure of vacuum, beyond standard quantum field theory.
See, for more details, the article "Dark matter and dark energy, or Pre-Big Bang geometry?", http://www.science20.com/relativity_and_beyond_it/blog/dark_matter_and_dark_energy_or_prebig_bang_geometry_i-109187 , in my Science 2.0 blog "Relativity and beyond it", http://www.science20.com/relativity_and_beyond_it
Best regards
Luis Gonzalez-Mestres, France