Starship Asterisk*

Why do you think that a red-shifted expanding universe and Big Bang theories are the same idea? They are different things. You could have either one without the other. They fit together into a single model, but saying you don't like one because you don't like the other is arguing from an uninformed point of view. To say simply that you don't believe in something and cast aspersions on anyone who does is not an argument at all. I have seen plenty of mud flung at the Big Bang in this forum, but I have yet to see a single logical or scientific argument presented by a mud flinger. Usually they just fling mud at logic and science (as practiced by the establishment, blah, blah, blah - get a life) as well.

Casus, I think it's interesting that you think that scientists or even us non-scientists "believe" in the Big Bang Theory. It's not about belief or faith. It's just a logical explanation for things based on observations, not myth or made up things. So, throw out the word "believe". They operate on what they know and do not know, not what they believe. Perhaps you yourself operate on faith and therefore you have concluded that other people must also operate on faith. I do not know.

Summary of alternative redshift theories
This is a selection of redshift theories that have been published over the years, that claim a cause that is not due to either Cosmological redshift (Friedmann), Doppler redshift, nor Gravitational redshift (Schwarzschild).

1909 John Evershed's "Evershed Effect"[7] in the penumbra of sunspots [8] [9].
1923 Compton scattering is Arthur Compton's Nobel Prize-winning theory which causes spectral shifts. However, critics note that it also causes blurring which is not seen in the redshifts of distant objects. [10] [11] [12] [13].
1929 Tired light is Fritz Zwicky's theory that as photons move through space, they lose energy [14]. Critics note several problems with tired light models in explaining the Hubble Law. It is not accepted by mainstream cosmologists as a mechanism. [15]
1955 M. A. Melvin's photon radiation density and path length [16]
1972 Dror Sadeh et al, "Effect of Mass on Frequency" [17]
1972 Daniel M. Greenberger's theory of "variable mass particles" which proposes a "decay redshift" [18]
1972 D.K. Ross's "New Red-Shift Mechanism for Quasars" using the variation of particle rest mass [19]
1972 J.C. Pecker, et al photon-photon interaction (in Pecker, J. C., Roberts, A. P., and Vigier, J. P., 1972, Non-velocity redshifts and photon-photon interactions: Nature, v. 237, p. 227-229). But see also [20]
1972 S. Urbanovich's "external influences" [21]
1974 Halton Arp suggests that the redshift of some quasars and galaxies may be non-velocity [22], and non-cosmological [23] (see also 1997 below).
1974 P. Merat et al, "Interaction between incident transverse photons and light neutral bosons" [24]
1976 Z. Maric et al, Photon-boson scattering [25]
1976 X.-Q. Li's photon motion in the discrete space-time under the photon's own force field [26]
1977 J. V. Narlikar's variable mass version of general relativity [27] [28]
1977 Susan M. Simkin's "Simkin effect" [29] [30] which is a description of one of the effects of light pollution.
1979 E. Schatzman's "Ageing of photons by collisions with a hypothetical particle" [31]
1979 E. R. Harrison and T. W. Noonan's "Interpretation of extragalactic redshifts" as ""Corrected" redshifts" [32]
1984 William G Tifft et al, "Global redshift quantization" [33] [34] [35]
1987 Emil Wolf's "Wolf effect" [36] , confirmed in the laboratory by Dean Faklis and George Morris in 1988 [37]. The frequency shift is generally not disortion free. However, in 1996, Wolf and Daniel F. V James reported that "under certain circumstances the changes in the spectrum of light scattered on random media may imitate the Doppler effect" [38] [39]
1990 Paul Marmet's inelastic transmission of photons in gases [40]
1997 Halton Arp suggests that redshift is a measure of age, rather than distance [41], based on Narlikar's variable mass version of general relativity [42] (resulting in Arp's book, Seeing Red).
2000 Ari Brynjolfsson's "Plasma redshift", that the interaction of photons with hot sparse electron plasma may produce a redshift [43] [44] [45]
2003 CREIL (Coherent Raman Effect on Incoherent Light) has been proposed by Jacques Moret-Bailly [46] [47]
2004 Charles Gallo's "Neutrino redshifts" [48] (not a new theory, but a proposal to look for redshifts in neutrino spectra)
To this list may be added several theories based on scattering processes, such as Brillouin scattering, Compton scattering, Raman scattering and Rayleigh scattering.

http://www.flickr.com/photos/jacobvorpahl/3049067456/ BB

If an explanation better than the BB is discovered then it will prove out. Right now the BB is the best explanation.!

Orin

Misconceptions about the Big Bang, Scientific American, March 2005
The Angry Astronomer: The Big Bang: Common Misconceptions
Common Joe: Three Most Common Misconceptions About the Big Bang

casusbelli wrote:BigBangers reluctantly keep making the universe older and older

apodman wrote:Not true.

Better knowledge, observations and tools cause to us constantly revise our estimate of the theoretical age of the universe. This is only to be expected.

casusbelli wrote:what explosion have you EVER seen that gets faster? NONE.

apodman wrote:The big bang was not an explosion.

casusbelli wrote:Sorry for the semantic surrender. Got any better terminology?

A common misconception. Fred Hoyle, a steady state proponent, is credited with coining the phrase Big Bang. Big Bang Theory makes no explanation about how the universe began, rather it tries to explain what came since.

All about Science: Big Bang Theory wrote: There are many misconceptions surrounding the Big Bang theory. For example, we tend to imagine a giant explosion. Experts however say that there was no explosion; there was (and continues to be) an expansion. Rather than imagining a balloon popping and releasing its contents, imagine a balloon expanding: an infinitesimally small balloon expanding to the size of our current universe.

Another misconception is that we tend to image the singularity as a little fireball appearing somewhere in space. According to the many experts however, space (and time) didn't exist prior to the Big Bang.

casusbelli wrote:Also, this "speeding up" of the expansion ... So, invent dark energy, dark matter

apodman wrote:The concepts of dark matter and dark energy were indeed invented to explain the way things are observed to work (which includes speeding up). Got any better ideas?

casusbelli wrote:Yes- seek another explanation for a redshift other than expansion (esp. accelerating expansion!)

casusbelli wrote:Give me proof of any dark matter - substantive proof.

apodman wrote:The mantra of those who don't understand the first thing about science or scientific method.

casusbelli wrote:Sorry for asking for proof. What do you need? FAITH???

Actually, as part of the most widely accepted cosmological model, the concordance model of big bang cosmology (aka ΛCDM), the burden of proof is on you if you don't agree. Dark Matter, Dark Energy? You can call them anything you want to, but you still have to account for their influence on the visible universe. Like it or not, the Lambda-Cold Dark Matter Model of Big Bang Cosmology remains as the best model to explain what we currently know about the universe. The model might be further revised as new evidence and theories (Hořava Gravity) accrue, but I don't see anything replacing it within my lifetime.

Observations of the cohesiveness and rotational velocity of galaxies couldn't be explained by the mass of the visible material. Furthermore, the orbital motions of galaxies in clusters, and the gravitational lensing of galaxy clusters (predicted by general relativity) couldn't be explained by the visible mass contained in those clusters. Something must be causing this, since we can't see it, let's call it dark matter.

Similarly, observations of type Ia supernovae indicated the universe was expanding (and at an increasing rate). Something must be causing this expansion. Meanwhile, observations of the cosmic microwave background radiation indicated the universe was flat. In order for this to be true, the universe must have a certain critical mass/energy density, but the amount of dark matter and ordinary matter could only account for about 26% of that density, something else made up the rest. Again we can't see this stuff that permeates all of space, so in keeping with dark matter, let's call it dark energy.

casusbelli wrote:Einstein didn't believe in the BB.

This isn't exactly true.

Wikipedia: Cosmological Constant wrote: Einstein included the cosmological constant as a term in his field equations for general relativity because he was dissatisfied that otherwise his equations did not allow, apparently, for a static universe: gravity would cause a universe which was initially at dynamic equilibrium to contract. To counteract this possibility, Einstein added the cosmological constant. However, soon after Einstein developed his static theory, observations by Edwin Hubble indicated that the universe appears to be expanding; this was consistent with a cosmological solution to the original general-relativity equations that had been found by the mathematician Friedman.

It is now thought that adding the cosmological constant to Einstein's equations does not lead to a static universe at equilibrium because the equilibrium is unstable: if the universe expands slightly, then the expansion releases vacuum energy, which causes yet more expansion. Likewise, a universe which contracts slightly will continue contracting.

Since it no longer seemed to be needed, Einstein called it the '"biggest blunder" of his life, and abandoned the cosmological constant. However, the cosmological constant remained a subject of theoretical and empirical interest. Empirically, the onslaught of cosmological data in the past decades strongly suggests that our universe has a positive cosmological constant. The explanation of this small but positive value is an outstanding theoretical challenge (see the section below).

Finally, it should be noted that some early generalizations of Einstein's gravitational theory, known as classical unified field theories, either introduced a cosmological constant on theoretical grounds or found that it arose naturally from the mathematics.

casusbelli wrote:what explosion have you EVER seen that gets faster? NONE. So, invent dark energy

that's why they call it dark, isn't it? because you cant EVER see it

bystander wrote:Dark Matter, Dark Energy? You can call them anything you want to, but you still have to account for their influence on the visible universe. Like it or not, the Lambda-Cold Dark Matter Model of Big Bang Cosmology remains as the best model to explain what we currently know about the universe.

i completely agree with the position taken by "bystander" or "apodman" on the superiority of "standard" cosmology to any other explanation available. after some early confusion about the geometry of the universe, and that small patch where the earth was estimated to be older than the universe, things do cohere to form a plausible narrative to connect the facts.

even so, it's right, in my view, to point out that dark matter, inflation, and even the singularity itself, so far as i know, have no physical explanation. there's no particle associated with dark matter, and no experimental way to look for it. inflation amounts to curve fitting, back to a singularity that occurs much too late to explain the size of universe we see. the singularity itself -- what the hell was that?

the difficulty is that these three phenomena (and the cosmological constant) are dynamic variables inferred to the explain what is essentially a static and structural view of the universe. novae, double stars, near star proper motions or parallaxes and deep space variable stars, quasars or black holes aside, we do not really see much change in the sky. and this leads to a fundamental quandry. red shift is attributed to doppler shift because that is the most parsimonious explanation -- the light behaves "as if" it were doppler shifted -- and because the doppler shift is an effect we already know. but dark matter is simply an "as if" explanation: it's not an effect seen elsewhere, but an effect that uniquely occurs only to explain structural data in a dynamic way. saying "you still have to explain their effect" begs the question of whether they exist -- whether, for example, the effect attributed to dark matter is not some property of space/time that is not readily visible in any other way but does not originate in "matter" per se. "dark matter" may just be a latter day ether, a substance created to explain a problem that doesn't exist.

larry krauss highlighted this problem late in a talk he gave to the AAI 2009, where he pointed out that, according to our current understanding, we just happen to live at that specific point in the history of the universe where we can see that our specific point in the history of the universe is remarkable, because only at this point would we clearly see how the universe actually originated and is evolving. that kind of thing makes me wary.

http://www.youtube.com/watch?v=7ImvlS8PLIo

sorry for the ramble but i feel this is an important issue for scientists to get clear on. on the one hand, science is under attack from the science illiterate and religiously motivated part of the population, and it has to been staunchly defended against those pressures. on the other hand, scientists should be more candid about the different levels of "proof" supporting different aspects of the scientific narrative, to defang the false accusation of faith. what we know, and know very firmly, is far too beautiful and precious to be held hostage to the speculative frontiers of science. those frontiers are necessary if knowledge is to advance. they are not necessary to communicate the importance of science to the larger culture.

drollere wrote:

larry krauss wrote:we just happen to live at that specific point in the history of the universe where we can see that our specific point in the history of the universe is remarkable, because only at this point would we clearly see how the universe actually originated and is evolving.

I thought the universe ceased to be opaque a few hundred thousand years after it began. So as I see it our remarkable point in history (though we've only occupied it recently) has lasted 13.3 billion years so far. Or does this lofty inspirational statement have a meaning I'm missing?

drollere wrote:i completely agree with the position taken by "bystander" or "apodman" on the superiority of "standard" cosmology to any other explanation available. after some early confusion about the geometry of the universe, and that small patch where the earth was estimated to be older than the universe, things do cohere to form a plausible narrative to connect the facts.

even so, it's right, in my view, to point out that dark matter, inflation, and even the singularity itself, so far as i know, have no physical explanation. there's no particle associated with dark matter, and no experimental way to look for it. inflation amounts to curve fitting, back to a singularity that occurs much too late to explain the size of universe we see. the singularity itself -- what the hell was that?

the difficulty is that these three phenomena (and the cosmological constant) are dynamic variables inferred to the explain what is essentially a static and structural view of the universe. novae, double stars, near star proper motions or parallaxes and deep space variable stars, quasars or black holes aside, we do not really see much change in the sky. and this leads to a fundamental quandry. red shift is attributed to doppler shift because that is the most parsimonious explanation -- the light behaves "as if" it were doppler shifted -- and because the doppler shift is an effect we already know. but dark matter is simply an "as if" explanation: it's not an effect seen elsewhere, but an effect that uniquely occurs only to explain structural data in a dynamic way. saying "you still have to explain their effect" begs the question of whether they exist -- whether, for example, the effect attributed to dark matter is not some property of space/time that is not readily visible in any other way but does not originate in "matter" per se. "dark matter" may just be a latter day ether, a substance created to explain a problem that doesn't exist.

First of all let me say that as far as I know, nothing in the standard model requires a singularity. In fact, the model breaks down under those conditions. That is part of the problem they have in trying to unite quantum physics with general relativity.

Redshift is real and it can be measured using standard candles. The most plausible explanation is that distant objects are all moving away from us, and the farther away they are, the faster they are moving. This is known as expansion. What causes it? We don't know. We can't see it or directly observe it, but we can observe it's effects. Call it negative pressure, vacuum energy, quintessence, cosmological constant, or dark energy. We can calculate how much there needs to be to explain what we do observe.

Dark matter? There is something that behaves like mass that holds galaxies and galaxy clusters together and causes light to appear to bend in what we call gravitational lensing. Again, we can not directly observe it and, therefore, do not know what it is, but we can observe its effects, and from those observations we can calculate how much of there needs to be. Call it whatever you want to, but you still have to explain its effects.

apodman wrote:I thought the universe ceased to be opaque a few hundred thousand years after it began. So as I see it our remarkable point in history (though we've only occupied it recently) has lasted 13.3 billion years so far. Or does this lofty inspirational statement have a meaning I'm missing?

save the sarcasm for a viewing of krauss's presentation. his point is made at around 0:40 or later in the 1 hour video linked above, which i decline to download and scan for you because i am on a bandwidth quota via satellite modem.

if i recall, his argument was that it takes a few rounds of stellar birth to produce metal rich stars that make complex life possible, so there are no observers in the early billions of years; and that at a late stage in cosmic history, all galaxies, even local ones, will have red shifted to frequencies so low that they would not be optically visible, and every galaxy would appear to its inhabitants to be the sole occupant of the universe. if you want details, please recur to krauss.

drollere wrote:

apodman wrote:I thought the universe ceased to be opaque a few hundred thousand years after it began. So as I see it our remarkable point in history (though we've only occupied it recently) has lasted 13.3 billion years so far. Or does this lofty inspirational statement have a meaning I'm missing?

save the sarcasm for a viewing of krauss's presentation. his point is made at around 0:40 or later in the 1 hour video linked above, which i decline to download and scan for you because i am on a bandwidth quota via satellite modem.

if i recall, his argument was that it takes a few rounds of stellar birth to produce metal rich stars that make complex life possible, so there are no observers in the early billions of years; and that at a late stage in cosmic history, all galaxies, even local ones, will have red shifted to frequencies so low that they would not be optically visible, and every galaxy would appear to its inhabitants to be the sole occupant of the universe. if you want details, please recur to krauss.

So you say krauss agrees with me that our remarkable point in history is an interval of at least several billion years. You have a funny way of expressing agreement. If he had another point beyond than that on which we agree, I wanted to know about it and I asked - no sarcasm intended.

bystander wrote:as far as I know, nothing in the standard model requires a singularity. Expansion ... what causes it? We don't know. ... Dark matter? ... We can not directly observe it and, therefore, do not know what it is, but ... we can calculate how much of there needs to be. Call it whatever you want to, but you still have to explain its effects.

of course, the structural features you call effects exist. they are well documented.

my point was that, for example, if you assume that dark matter has mass like *ordinary matter*, then you can compute how much ordinary matter would be necessary to produce the metric accelerating or galaxy shaping or light lensing effects actually observed and attributed to -- matter that you cannot see.

but you have assumed that the cause here is an entirely new and mysterious kind of matter, rather than an entirely new and mysterious kind of ... something else. for example, an enhanced curvature of space time produced by angular momentum in galaxy sized masses. such a thing is not predicted in standard physics, but neither is dark matter.

my theme isn't competing hypotheses, but the presentation of certitude. science has far too much to be certain about to extend the privilege to string theory, quantum bubbles, dark matter and inflation.

and this is a divert anyway ... i had two technical questions about deep field images. looking forward to answers.

The trouble with dark matter (or with its theoretical substitute by any other name) is that it walks like a duck but does not quack like a duck. You are half in trouble whatever you call it, but three syllables is a good limit for a term. That's why I'm 33% less excited about what we are calling dark energy.

drollere wrote:but you have assumed that the cause here is an entirely new and mysterious kind of matter, rather than an entirely new and mysterious kind of ... something else. for example, an enhanced curvature of space time produced by angular momentum in galaxy sized masses. such a thing is not predicted in standard physics, but neither is dark matter.

No, I have assumed there are phenomena which can be observed and must be explained in whichever model you use. Call them Bob, Carol, Ted and Alice. I don't care what you call them, or how you explain them, but they must be accounted for in any model that is proposed. In ΛCDM, the current generally accepted model, the mechanisms are called dark matter and dark energy, and they satisfy the model. Maybe at some point in the future, ΛCDM may be replaced (or modified), but until then, ...

Bystander-
I'm so new here that I can't reply to your PM. Thanks for it; I'll respond here.
You are totally correct. And as the interlooper here, I have no right to attack mainstream scientific thought (even if it is suspect). It's the iconoclast in me. Your comments were constructive.
-snip - laundry removed
You all can say what you like, but it remains my opinion that dark energy and dark matter theories are just inventions to make the data jive with the expansion of the universe (and an accelerating one at that), and therefore it is fair to compare them with the old planetary epicycles. [Until there is confirmatory proofs (plural) of these dark entities (like there were for the speed of light), then it would behoove everyone to treat dissenting opinion with at least a rudimentary politeness. Otherwise you just prove the censorship against non-BB inquiry as alleged by Prof. Arp.] EVERYTHING in distant measurements - distance, absolute magnitude, mass, age, etc, is based on the redshift of the thing measured. Too many eggs in one basket. IM(newly)HO.

casusbelli wrote:I'm so new here that I can't reply to your PM.

When reading one sent to you, just click SendReply. Do not air your dirty laundry in this forum.

casusbelli wrote:You all can say what you like, but it remains my opinion that dark energy and dark matter theories are just inventions to make the data jive with the expansion of the universe

No one claims to know what they are (except maybe detractors), they are just names of mechanisms used to explain observed phenomena in the current best fit model. It's just observations, physics, and mathematics. No magic here.

casusbelli wrote:censorship against non-BB inquiry as alleged by Prof. Arp.

Halton Arp is a well respected astronomer, but his theories in cosmology (tired light, et al) are not well received and are not substantiated by observations (emissions spectra). It's not censorship, it's just a matter of which model better explains the observations and can make testable predictions.

casusbelli wrote:EVERYTHING in distant measurements - distance, absolute magnitude, mass, age, etc, is based on the redshift of the thing measured.

Of course they are, they are all interrelated. Just look at the formula.

What could stop expansion? Or slow it down? Or speed it up?

Where is the new space time coming from?

If 13.7 billion years ago all space time was at one point, why, that what makes up space time, does not act like other matter?

could a sub-atomic pin point in space time be dissolved and emerges due to a seemingly unrelated reason?

What happens to a photon when there is no place to go? The End, The Edge of our universe.

Is matter radiating more than light? etc etc.

Is there a comparison to the expansion of the universe, and the expansion of the milky way, and are the other local galaxies uniform?

G'day casusbelli

I think you are on track. Keep questioning and if you can back it with science all the better. That is what science is about.

The BB theory is a theory that states the expansion of space/time not the actual metric distances. This is why when we observe images we do not see the expansion but the clustering affect due to gravity.

Shakespeare wrote:Once more unto the breach

• Henry V, Act III

Why do you keep asking these same questions, or ones so similar it makes no difference. Do you not like the answers?
I hope you are not acting as a proxy for sputnick. He used to do the same thing. One more time, here's my version.

mark swain wrote:What could stop expansion? Or slow it down? Or speed it up?

What do you think causes expansion? Whatever, less of it would slow it down. Even less would stop it. More would speed it up. I'm not sure it really matters. It's not something that we have any control over, nor is it something that's likely to change on its own.

Where is the new space time coming from?

What new space-time? There is no new space-time, there is just space-time. Space-time came into existance at the same time as the universe. No more is being created, it's just being stretched.

If 13.7 billion years ago all space time was at one point, why, that what makes up space time, does not act like other matter?

Why do you keep insisting that it all had to be one point (singularity)? There is nothing in the standard model that requires a singularity. In fact, the model becomes undefined if you try to make any of the four dimensions of space-time zero. What makes up space-time? Space and time, it has absolutely nothing to do with matter and energy. Think of space and time as the four dimensions used to locate any point in our (4d) universe. Matter and energy compose the objects that occupy our universe.

could a sub-atomic pin point in space time be dissolved and emerges due to a seemingly unrelated reason?

Who knows. Singularities have not been (can not be?) effectively modeled. What happens in a singularity remains undefined.

What happens to a photon when there is no place to go? The End, The Edge of our universe.

Unless you are talking about Milliways, there is no edge or end to our universe. It is continuous (which is not the same as infinite and eternal, though it may be either or both of those, too). And light does not get tired.

Is matter radiating more than light? etc etc.

I'm not sure what you are asking. If you mean light as in electro magnetic radiation (energy), then no. If you mean light as in that very narrow band of emr that we humans call visible light, then yes, it radiates across the entire emr spectrum. If you are comparing matter to light, then you are comparing apples to oranges and the question is meaningless.

Is there a comparison to the expansion of the universe, and the expansion of the milky way, and are the other local galaxies uniform?

No, there is no comparison. The universe is expanding, not galaxies (except by absorbing companion galaxies). Galaxy clusters, galaxies, stellar (solar) systems, stars and planets are all held together by gravity. At larger scales, expansion takes over.

bystander wrote:Why do you keep asking these same questions, or ones so similar it makes no difference. Do you not like the answers? I hope you are not acting as a proxy for sputnick. He used to do the same thing. One more time, here's my version.

bystander, i don't envy you your task, but i want to make a general observation about the underlying problem here. it's basically of the form:

1. REAL EFFECT --> 2. [UNKNOWN] CAUSE --> 3. METAPHORICAL CAUSE --> 4. LITERAL INTERPRETATION

a lot of the questions you are batting around come up because the person makes the step from 3 to 4, for example:

1. red shift
2. cosmological expansion
3. originating "big bang"
4. "have you ever seen an explosion slow down?", "where did all the new space come from?", etc.

i am not sure how to address this kind of science illiteracy. for example, cosmological geometry and the curvature of space seems to be a problem for your poster.

the illiteracy seems to be enflamed by the step from 2 to 3, where (for example), gravitational lensing or galaxy rotation suggest a gravitational effect that cannot be attributed to visible matter, and is described as a "dark" kind of matter instead. as you pointed out, that is basically a placeholder for an unsolved problem (the "dark matter" particle is unidentified), but the metaphor is also appropriated for interpretations that go beyond the point of the metaphor and can even make the metaphor look like a ridiculous claim.

the step from 1 to 2 is an inference, and a fairly strong one. the step from 3 to 4 is a misunderstanding, and a fairly common one. so i infer that 2 to 3 is the place to focus in order to address the misunderstanding at 4.

as i said in a previous post, cosmologists should reserve certitude, or talk that sounds like it, for 1 and usually 2, and something more tentative for 3. i know that astronomers do not choose their metaphors with an eye to public misinterpretation, but it looks like the responsibility of dealing with 4 is one of the outcomes.

mark swain wrote:What could stop expansion? Or slow it down? Or speed it up?

the underlying cause of the expansion is unknown, so anything that might affect it cannot be talked about.

mark swain wrote:Where is the new space time coming from?

you seem to imagine space as a quantity, such as a quantity of matter, so that to increase space more of it must be added, like pouring sand into an hourglass. space is just getting larger, in the same way an image gets larger if you project it onto a farther screen.

because the speed of light (and not time) is a universal constant, it serves as the ultimate arbiter of distance and time. the "space time" distance that light can cover in a fixed time stays the same; but because space is apparently expanding, the actual time it takes the light to cross a given distance takes longer. this produces the doppler red shift in the light.

mark swain wrote:If 13.7 billion years ago all space time was at one point, why, that what makes up space time, does not act like other matter?

matter is matter and space time is space time. they are completely different things.

mark swain wrote:could a sub-atomic pin point in space time be dissolved and emerges due to a seemingly unrelated reason?

i have no idea what you are asking here, but there is only conjecture about the cause of a singularity that could originate all energy and space time simultaneously. matter eventually condensed out of the original radiation as it cooled, much as rain condenses out of a cloud.

mark swain wrote:What happens to a photon when there is no place to go? The End, The Edge of our universe.

the universe is curved in three dimensions in the same way that the surface of the earth is curved in two dimensions. that is, although we normally (walking, driving) think of the earth as having two dimensions, like a map, there is no edge to the surface of the earth, because it is actually a sphere. if you traveled on the surface of the earth in a straight line in any direction, you would eventually return to your starting point. in the same way, although we normally (walking, driving, flying, orbiting) think of space as three dimensional in a straight line, the universe is actually curved in a way that three dimensional travel in a straight line would (after a *very* long time) return to the starting point.

mark swain wrote:Is matter radiating more than light? etc etc.

yes. light is just the electromagnetic radiation that produces a response in our eyes. heat, microwaves, etc. are also "light" or electromagnetic radiation, but at a frequency (energy) that is too low for our eyes to see; ultraviolet and x rays are also "light" or electromagnetic radiation but at a frequency (energy) that is too high for our eyes to perceive (and can damage them).

mark swain wrote:Is there a comparison to the expansion of the universe, and the expansion of the milky way, and are the other local galaxies uniform?

don't know what you mean by "uniform". the current understanding is that the cosmological expansion does not affect the dimensions of matter bound by gravity. space is expanding, and carrying galaxies farther apart, but the "light speed" dimensions of the galaxies themselves remain unchanged. (galaxies can also fly away from each other at a speed greater than the speed of light if the separation is caused by cosmological expansion, but not if the separation is caused by physical momentum.) why that happens is not known.

drollere wrote:the underlying cause of the expansion is unknown, so anything that might affect it cannot be talked about.

Unless

drollere wrote:don't know what you mean by "uniform". the current understanding is that the cosmological expansion does not affect the dimensions of matter bound by gravity.

So Gravity would stop expansion. So what do scientists mean when they state, space time is falling into a black hole like a water fall? Is space time infernally stretchy?

drollere wrote:you seem to imagine space as a quantity, such as a quantity of matter, so that to increase space more of it must be added, like pouring sand into an hourglass. space is just getting larger, in the same way an image gets larger if you project it onto a farther screen.

Who said space and time were an item? http://www.scientificamerican.com/artic ... from-space

drollere wrote:matter is matter and space time is space time. they are completely different things.

Quantum fluctuations. http://www.newscientist.com/article/dn1 ... tions.html


Thank you for your time drollere.

mark swain wrote:So Gravity would stop expansion.

No, gravity is too weak of a force at the scales where expansion takes over.

So what do scientists mean when they state, space time is falling into a black hole like a water fall? Is space time infernally stretchy?

Having been around when you introduced this, I know where this is coming from, although I can't find it. Again, the waterfall was an analogy used to try to explain how black holes warp space-time so much, light can not escape. Space-time is not disappearing any more than new space-time is being created.

Who said space and time were an item?

Actually, Einstein did. That's kind of what GR is all about.

http://www.scientificamerican.com/artic ... from-space

Interesting article. It may cause a major rethinking of GR and the standard model.
http://asterisk.apod.com/vie ... =8&t=17702

Quantum fluctuations. http://www.newscientist.com/article/dn1 ... tions.html

Quantum fluctuations do not in any way equate space-time to energy or matter.

bystander wrote: mark swain wrote:So Gravity would stop expansion.


No, gravity is too weak of a force at the scales where expansion takes over.

So why do galaxies cling together in a string, and the voids get bigger and bigger?

bystander wrote:the waterfall was an analogy used to try to explain how black holes warp space-time so much, light can not escape. Space-time is not disappearing any more than new space-time is being created.

Why would space and time not be effected by huge gravity forces when expansion is stretching it to breaking point?

bystander wrote: Who said space and time were an item?


Actually, Einstein did. That's kind of what GR is all about.

http://www.scientificamerican.com/artic ... from-space


Interesting article. It may cause a major rethinking of GR and the standard model.
viewtopic.php?f=8&t=17702

Excellent.

bystander wrote:Quantum fluctuations do not in any way equate space-time to energy or matter.

http://www.aip.org/pt/nov99/wilczek.html

mark swain wrote:So why do galaxies cling together in a string, and the voids get bigger and bigger?

There is enough mass within the galaxy clusters for gravity to hold them together and perhaps form some cohesiveness between them (filaments). But there are isolated galaxies and galaxy clusters within those voids that will never be a part of those filaments. Think of a large bowl of soap bubbles. The filaments are the surfaces of the bubbles and the voids are their interiors. There are plenty of simulations that predict this is exactly the large scale structure we should expect given the standard model and those early quantum fluctuations.

Why would space and time not be effected by huge gravity forces when expansion is stretching it to breaking point?

Gravity decreases with the square of distance. So, at the large scale distances that expansion holds sway, gravity has very little effect. Expansion cannot cause huge gravity forces.

What is the breaking point of space-time? Does it even have one? There have been some hypotheses proposed that sugggest this is so, but I don't give them much credance.

No "Big Rip" in our Future: Chandra Provides Insights Into Dark Energy
Dark Energy Found Stifling Growth in Universe

Who said space and time were an item?

Actually, Einstein did. That's kind of what GR is all about.

http://www.scientificamerican.com/artic ... from-space

Interesting article. It may cause a major rethinking of GR and the standard model.
http://asterisk.apod.com/vie ... =8&t=17702

This new theory has yet to prove out and has already undergone some major revisions of its own. But still interesting, we'll just have to wait and see what develops. This may even be that breakthrough we need to finally unite quantum theory with GR.

Quantum fluctuations. http://www.newscientist.com/article/dn1 ... tions.html

Quantum fluctuations do not in any way equate space-time to energy or matter.

http://www.aip.org/pt/nov99/wilczek.html

I see no reason to revise my earlier statement.