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#11
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It seems that as Dark Energy increases, Dark Matter decreasesastime goes on
Dear Yousuf Kahn:
On Friday, November 16, 2012 4:48:16 PM UTC-7, Yousuf Khan wrote: On 14/11/2012 10:50 PM, dlzc wrote: On Wednesday, November 14, 2012 7:21:26 PM UTC-7, Yousuf Khan wrote: .... We have no idea whether Dark Matter is WIMPs, and since we've never seen WIMPs, then chances are likely that they aren't. Not having seen WIMPs, we have no idea if they interact and annihilate each other. I don't expect there are either, but they would agree with this observation. Except we should be seeing a lot of gamma rays from Dark Matter annihilation events in the distant universe. The Gamma ray events are so far all just normal supernovas, quasars, etc. I can't see highly ionized normal matter being enough to explain Dark Matter either. There simply can't be enough to make up the shortfall, There was, even before we saw all the ionized gas between stars and between galaxies, and the fields of individual stars in intergalactic space... not allocated to galaxies. This does stagnate the mass in planet-mass-and-larger black holes, however, as they would tend to increase Dark Matter in forward time... I don't get what you're saying here. Are you saying that there are planet-mass blackholes in intergalactic space making up the Dark Matter? *If* they existed, they would comply with the requirements of Dark Matter. If they existed they would have to be net not growing, to comply with this observation. That would mean the MACHO model of Dark Matter. Each observation applies to all possible (relevant) theories. although it might be able to make up some small percentage of it. I understand you are not convinced. So if DM is not either of these things, Just because you are not convinced, does not mean you can throw them out. I don't believe we'll find any one thing likely to be called Dark Matter (whether it be WIMPs, MACHOs, or just missing baryonic matter), nor will any combination of them be enough to account for all of the effect. But normal matter *alone* could describe spiral galaxy curves and microlensing, even before the discoveries I mention above. "Something special" was required in the dusty outer rim, and so... My feeling is that the majority of the effect is just a reshaping of the gravitational force effects. OK, but this is not required, is not detectable in the laboratory, and violates the laws of physics not changing over time. then it's got to be an effect of vacuum energy, just like DE is supposed to be. That tool is blunted, as previously discussed. The "energy", and the nature of that "energy" was unchanged. No, Dark Energy and Dark Matter might be just an exchange of negative energy (gravitational pull) for positive energy (accelerated expansion), and vice-versa. All of the matter in the universe is made of positive energy, while all of its gravitational pull is made of negative energy. Sorry, this is just so much wind here. In the Inflationary period, a large amount of positive push energy pushed the universe out very quickly, and then that positive energy got converted into matter If it was not already matter, no push was required. which reduced the positive energy's runaway pushing by locking it up. That then gave the negative gravitational energy, which is normally very randomized and spread out, enough breathing space to take hold of the universe and begin slowing it down again. It didn't slow down, it just didn't expand very fast. Then virtual particles (which are also matter and anti-matter, thus made of positive energy) No, they are not. They are massless. would start releasing positive energy into intergalactic voids to begin another, albeit smaller, pushing effort again. This is just going downhill, Yousuf. Inflation occurred before matter appeared, Based on??? thus the entire positive energy reserve was used to push the universe out. When matter appeared, the universe's pushing era ended, because it got locked up into matter/antimatter. Now in the present stated of the universe, some of that matter/antimatter creates a mini re-emergence of positive push era again: not as large or as spectacular as the Inflationary era, but still a sort of push era. None of which Science can support, since you alter physics to do it. .... Dark Matter shouldn't go up and down in magnitude, Sure can, as discussed above. WIMPs interact to become normal, and ionized (therefore dark) becomes less so. If WIMPs interact with each other and annihilate, then they won't become normal baryonic matter, they will become gamma ray photons, thus not stable matter. That is not correct. Massive normal matter is supposed to result, with less total energy carried off by the photons. And electrons entering orbitals convert more ionized matter (dark matter) to less ionized matter. only forms of energy can do that by transforming between one type and another. Doesn't matter what type, both are attractive in GR, as both must act like mass "in the large". Not if the types of energy are negative energy vs. positive. Energy is one "term" in GR. It is attractive. Negative energy is just what we normally call gravitation, thus its opposite form of energy is positive energy which is a push-type energy. Sorry, no. .... Matter is mostly stuck in its own form most of the time. Nope. Interacting, forming stars and planets, reaching ground state, heck even micro black holes evaporating... plenty easy to become less Dark. I meant matter is stuck being baryons most of the time. I don't mean whether they become stars or planets or stuff like that. They stay pretty stably in the form of baryons. But ionized matter is essentially dark. So it can go from being dark, to being non-dark simply by cooling... by being in a cooler Universe. .... Well, we're not talking about Big Bang conditions, at that time, it's likely the energy at that time was all converted to a push-type energy before settling down to become pull-type again. I am unconvinced. I see no mechanism. Dark Energy and Dark Matter are tied down at the time of CMBR emissions, really not much wiggle room. As stated above, the Inflationary epoch was when Dark Energy managed to runaway unhindered since matter hadn't formed yet to lock it down into a self-contained crystallized form. The red shift of CMBR radiation is 1000 or so. The CMBR was light emitted from normal matter, self-pumped hydrogen ions. Only 300,000 years later, the red shift was 6 or 7. So the CMBR was normal matter, that existed during the inflationary period. I have no idea where your cosmology is coming from. David A. Smith |
#12
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It seems that as Dark Energy increases, Dark Matter decreases as time goes on
In article ,
dlzc writes: Having Dark Energy as "stuff" (as opposed to the cosmological constant) allows for it to be non-uniformly distributed in space and time, subject to observational support of course. Sorry to be slow getting back to this. Dark matter is just matter. Its exact nature is unknown except that most of it is non-baryonic. (There's also baryonic dark matter, but all the baryons dark and otherwise make up only 4% of the Universe in today's standard cosmology.) In particular, the density of dark matter varies in space and time, and the statistics of its distribution can be calculated under any assumptions one likes. (Typically these are that the non-baryonic dark matter interacts only by gravitation and that its total amount is fixed, but other assumptions could be put into the models. The calculations are not perfect by any means, but they are probably OK for non-baryonic matter at scales of whole galaxies and larger. Calculating what the baryons do is extremely complicated because they interact non- linearly to make stars, planets, and protoplasm among other things.) Dark energy is conceived to be a property of space, independent of the matter in it. A cosmological constant is one example. By definition, the classical cosmological constant does not vary with time, but it's easy to imagine "something like a cosmological constant but potentially varying with time." That's what "dark energy" means. It's perhaps not ideal terminology, but something was needed to distinguish a parameter with potential time variation from one without (cosmological constant). I think "time-variable cosmological constant" would have been worse? (What is a variable constant?!) There is much more at http://www.astro.ucla.edu/~wright/cosmo_constant.html Measuring the time variation of dark energy is really hard. For now, possible variation is usually represented as just a single parameter, and all observations (so far as I know) are consistent with no time variation, i.e., that dark energy is a cosmological constant. (This is expressed as "w = -1;" see the link above.) Better supernova measurements and baryon acoustic oscillations should pin this down better in the next several years. It could turn out that a yet more complex model with dark energy varying in space is required to fit the data, but we are very far from needing that right now. -- Help keep our newsgroup healthy; please don't feed the trolls. Steve Willner Phone 617-495-7123 Cambridge, MA 02138 USA |
#13
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It seems that as Dark Energy increases, Dark Matter decreases astime goes on
Dear Steve Willner:
On Monday, December 17, 2012 3:27:20 PM UTC-7, Steve Willner wrote: In article , dlzc writes: Having Dark Energy as "stuff" (as opposed to the cosmological constant) allows for it to be non-uniformly distributed in space and time, subject to observational support of course. Sorry to be slow getting back to this. Dark matter is just matter. Its exact nature is unknown except that most of it is non-baryonic. Based on what is this conclusion reached? (There's also baryonic dark matter, but all the baryons dark and otherwise make up only 4% of the Universe in today's standard cosmology.) "Standard" was defined based on (now) significant errors in calibrating to a spiral galaxy. The center is swept clear. Intensity is a function temperature, the center is hot, and the disk is not. Vast pools of ionized normal matter, and even individual stars we find outside our disk. In particular, the density of dark matter varies in space and time, and the statistics of its distribution can be calculated under any assumptions one likes. (Typically these are that the non-baryonic dark matter interacts only by gravitation and that its total amount is fixed, but other assumptions could be put into the models. The calculations are not perfect by any means, but they are probably OK for non-baryonic matter at scales of whole galaxies and larger. Calculating what the baryons do is extremely complicated because they interact non-linearly to make stars, planets, and protoplasm among other things.) There lay the glory in which we are immersed. Dark energy is conceived to be a property of space, independent of the matter in it. A cosmological constant is one example. By definition, the classical cosmological constant does not vary with time, but it's easy to imagine "something like a cosmological constant but potentially varying with time." That's what "dark energy" means. It's perhaps not ideal terminology, but something was needed to distinguish a parameter with potential time variation from one without (cosmological constant). I think "time-variable cosmological constant" would have been worse? (What is a variable constant?!) Let's see: - Hubble constant - VSL comsologies .... it is a choice of word, with foundations in history. Should not be considered to be a pronouncement. Measuring the time variation of dark energy is really hard. For now, possible variation is usually represented as just a single parameter, and all observations (so far as I know) are consistent with no time variation, i.e., that dark energy is a cosmological constant. (This is expressed as "w = -1;" see the link above.) Better supernova measurements and baryon acoustic oscillations should pin this down better in the next several years. It could turn out that a yet more complex model with dark energy varying in space is required to fit the data, but we are very far from needing that right now. Or even seeing it. Thank you. David A. Smith |
#14
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It seems that as Dark Energy increases, Dark Matter decreases as time goes on
"Steve Willner" wrote in message ...
In article , dlzc writes: Having Dark Energy as "stuff" (as opposed to the cosmological constant) allows for it to be non-uniformly distributed in space and time, subject to observational support of course. Sorry to be slow getting back to this. Dark matter is just matter. Its exact nature is unknown except that most of it is non-baryonic. ================================================== Help keep our newsgroup healthy; please don't feed the baryonic trolls like Willner. |
#15
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It seems that as Dark Energy increases, Dark Matter decreasesastime goes on
Hmm, these replies just recently appeared on my news server, even though
they were posted a month ago. On 19/11/2012 3:09 PM, dlzc wrote: Dear Yousuf Kahn: On Friday, November 16, 2012 4:48:16 PM UTC-7, Yousuf Khan wrote: My feeling is that the majority of the effect is just a reshaping of the gravitational force effects. OK, but this is not required, is not detectable in the laboratory, and violates the laws of physics not changing over time. I doubt that this law has been absolutely proven. It may hold true within our current era, but that's just a localized phenomenon. then it's got to be an effect of vacuum energy, just like DE is supposed to be. That tool is blunted, as previously discussed. The "energy", and the nature of that "energy" was unchanged. No, Dark Energy and Dark Matter might be just an exchange of negative energy (gravitational pull) for positive energy (accelerated expansion), and vice-versa. All of the matter in the universe is made of positive energy, while all of its gravitational pull is made of negative energy. Sorry, this is just so much wind here. Gravity is often thought of as negative energy. So that leaves everything else as being made of positive energy. Zero-energy universe - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Zero-energy_universe In the Inflationary period, a large amount of positive push energy pushed the universe out very quickly, and then that positive energy got converted into matter If it was not already matter, no push was required. The matter would've had to come later, after Inflation ended. That which is being "pushed", is space itself. which reduced the positive energy's runaway pushing by locking it up. That then gave the negative gravitational energy, which is normally very randomized and spread out, enough breathing space to take hold of the universe and begin slowing it down again. It didn't slow down, it just didn't expand very fast. Whatever you say. Then virtual particles (which are also matter and anti-matter, thus made of positive energy) No, they are not. They are massless. They are virtually massless. They end up cancelling each other's mass, of course. But I never said anything about having mass, it's not even relevant, what's relevant is their energy they release. would start releasing positive energy into intergalactic voids to begin another, albeit smaller, pushing effort again. This is just going downhill, Yousuf. Inflation occurred before matter appeared, Based on??? Chronology of the universe - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Chronol...ationary_epoch Inflationary Big Bang would require that the baryons and leptons only appear after Inflation ended. Yousuf Khan |
#16
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It seems that as Dark Energy increases, Dark Matter decreasesastime goes on
Dear Yousuf Khan:
On Monday, December 17, 2012 6:07:45 PM UTC-7, Yousuf Khan wrote: .... Hmm, these replies just recently appeared on my news server, even though they were posted a month ago. On 19/11/2012 3:09 PM, dlzc wrote: Dear Yousuf Kahn: On Friday, November 16, 2012 4:48:16 PM UTC-7, Yousuf Khan wrote: My feeling is that the majority of the effect is just a reshaping of the gravitational force effects. OK, but this is not required, is not detectable in the laboratory, and violates the laws of physics not changing over time. I doubt that this law has been absolutely proven. Nothing is Science can be. It may hold true within our current era, but that's just a localized phenomenon. Fine structure constant does not change as much as 1 part in 10^8 over the displayed history of the Universe, and the observations you have drawn your conclusions on *assume* no change in physics over that time. then it's got to be an effect of vacuum energy, just like DE is supposed to be. That tool is blunted, as previously discussed. The "energy", and the nature of that "energy" was unchanged. No, Dark Energy and Dark Matter might be just an exchange of negative energy (gravitational pull) for positive energy (accelerated expansion), and vice-versa. All of the matter in the universe is made of positive energy, while all of its gravitational pull is made of negative energy. Sorry, this is just so much wind here. Gravity is often thought of as negative energy. Incorrectly so, since it is energy-neutral. So that leaves everything else as being made of positive energy. Zero-energy universe - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Zero-energy_universe Still just wind. In the Inflationary period, a large amount of positive push energy pushed the universe out very quickly, and then that positive energy got converted into matter If it was not already matter, no push was required. The matter would've had to come later, after Inflation ended. That which is being "pushed", is space itself. Which arises from matter / energy, and cannot exist without it. Which is why it plays such a strong role in the curvature of spacetime. .... Then virtual particles (which are also matter and anti-matter, thus made of positive energy) No, they are not. They are massless. They are virtually massless. They are *exactly* massless, since the quantum realm does not touch mass until it maps back into the classical realm. They end up cancelling each other's mass, of course. But I never said anything about having mass, it's not even relevant, what's relevant is their energy they release. It is not relevant, because gravitation is not a force, and expansion, even acceleration of expansion, does not require energy, even if matter is involved. You either throw out the baby and bathwater that provided you the observations you are playing in mudpies with, or you accept the assumptions that provided you those observations. .... Inflation occurred before matter appeared, Based on??? Chronology of the universe - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Chronol...ationary_epoch Inflationary Big Bang would require that the baryons and leptons only appear after Inflation ended. David A. Smith |
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It seems that as Dark Energy increases, Dark Matter decreases as time goes on
SW Dark matter is just matter. Its exact nature is
SW unknown except that most of it is non-baryonic. In article , dlzc writes: Based on what is this conclusion reached? Originally on abundances of light nuclides: http://astro.berkeley.edu/~mwhite/darkmatter/bbn.html Nowadays I think CMB fluctuations provide tighter constraints: http://map.gsfc.nasa.gov/resources/camb_tool/index.html I don't understand the rest of the post. -- Help keep our newsgroup healthy; please don't feed the trolls. Steve Willner Phone 617-495-7123 Cambridge, MA 02138 USA |
#18
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It seems that as Dark Energy increases, Dark Matter decreasesastime goes on
On 18/12/2012 11:21 AM, dlzc wrote:
Dear Yousuf Khan: On Monday, December 17, 2012 6:07:45 PM UTC-7, Yousuf Khan wrote: ... Hmm, these replies just recently appeared on my news server, even though they were posted a month ago. On 19/11/2012 3:09 PM, dlzc wrote: OK, but this is not required, is not detectable in the laboratory, and violates the laws of physics not changing over time. I doubt that this law has been absolutely proven. Nothing is Science can be. It may hold true within our current era, but that's just a localized phenomenon. Fine structure constant does not change as much as 1 part in 10^8 over the displayed history of the Universe, and the observations you have drawn your conclusions on *assume* no change in physics over that time. It's hard to tell what the laws of physics were like during the Inflationary Big Bang period. We can only see as far back as the CMBR, i.e. 300k years after the BB, which would already be too late after the Inflationary period. By the time of the CMBR, the Universe had already settled into its current stable state. The Fine Structure Constant was pretty much already at the current level, give or take a few parts per whatever. However, during Inflation that FSC might have been quite wildly different. Gravity is often thought of as negative energy. Incorrectly so, since it is energy-neutral. No idea where you get that. In the Inflationary period, a large amount of positive push energy pushed the universe out very quickly, and then that positive energy got converted into matter If it was not already matter, no push was required. The matter would've had to come later, after Inflation ended. That which is being "pushed", is space itself. Which arises from matter / energy, and cannot exist without it. Which is why it plays such a strong role in the curvature of spacetime. Or more likely matter-energy requires space-time, and cannot exist without it. I don't even think this is just another classic chicken/egg problem, I think it's quite plainly obvious that energy condenses out of spacetime, and that matter condenses out of energy. I think spacetime is the basic building block, and energy and then matter come out of that. Yousuf Khan |
#19
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It seems that as Dark Energy increases, Dark Matter decreasesas time goes on
On 21/12/2012 6:03 PM, Steve Willner wrote:
SW Dark matter is just matter. Its exact nature is SW unknown except that most of it is non-baryonic. In , writes: Based on what is this conclusion reached? Originally on abundances of light nuclides: http://astro.berkeley.edu/~mwhite/darkmatter/bbn.html Nowadays I think CMB fluctuations provide tighter constraints: http://map.gsfc.nasa.gov/resources/camb_tool/index.html Isn't it true that the reasons for the CMB spectrum are complete guesswork? Originally before the discovery of Dark Energy, it was thought that the spectrum was as a result of neutrinos? The previous best model for CMB was known as "Mixed Dark Matter", which consisted of 80% CDM & 20% neutrinos. The Mixed Dark Matter model fit the CMB just as well as Lambda-CDM did, and it still does, except that Dark Energy is now the curve-fit-du-jour. Mixed dark matter - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Mixed_dark_matter Yousuf Khan |
#20
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It seems that as Dark Energy increases, Dark Matter decreasesastime goes on
Dear Yousuf Khan:
On Monday, December 24, 2012 1:24:25 AM UTC-7, Yousuf Khan wrote: On 18/12/2012 11:21 AM, dlzc wrote: On Monday, December 17, 2012 6:07:45 PM UTC-7, Yousuf Khan wrote: On 19/11/2012 3:09 PM, dlzc wrote: OK, but this is not required, is not detectable in the laboratory, and violates the laws of physics not changing over time. I doubt that this law has been absolutely proven. Nothing is Science can be. It may hold true within our current era, but that's just a localized phenomenon. Fine structure constant does not change as much as 1 part in 10^8 over the displayed history of the Universe, and the observations you have drawn your conclusions on *assume* no change in physics over that time. It's hard to tell what the laws of physics were like during the Inflationary Big Bang period. We can only see as far back as the CMBR, The observation that started this post was clearly this side of the CMBR. And the observation *assumed* the laws of physics did not change over that time, to reach their conclusions. i.e. 300k years after the BB, which would already be too late after the Inflationary period. By the time of the CMBR, the Universe had already settled into its current stable state. The Fine Structure Constant was pretty much already at the current level, give or take a few parts per whatever. However, during Inflation that FSC might have been quite wildly different. Sure. And the CMBR might be what our container Universe looks like, and there was no Big Bang. Gravity is often thought of as negative energy. Incorrectly so, since it is energy-neutral. No idea where you get that. Gravity just changes "energy of position" to "energy of motion", net energy does not change, until friction kicks in. In the Inflationary period, a large amount of positive push energy pushed the universe out very quickly, and then that positive energy got converted into matter If it was not already matter, no push was required. The matter would've had to come later, after Inflation ended. That which is being "pushed", is space itself. Which arises from matter / energy, and cannot exist without it. Which is why it plays such a strong role in the curvature of spacetime. Or more likely matter-energy requires space-time, and cannot exist without it. I don't even think this is just another classic chicken/egg problem, I agree here, however... I think it's quite plainly obvious that energy condenses out of spacetime, and that matter condenses out of energy. I think spacetime is the basic building block, and energy and then matter come out of that. Time evolves from the 2nd law of thermodynamics, and space evolves from conservation of momentum and multiple bodies. So to me it is most likely that they all cooked out *precisely* together. David A. Smith |
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