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It seems that as Dark Energy increases, Dark Matter decreases astime goes on



 
 
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  #11  
Old November 19th 12, 09:09 PM posted to sci.astro
dlzc
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Posts: 1,426
Default 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
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  #12  
Old December 17th 12, 11:27 PM posted to sci.astro
Steve Willner
external usenet poster
 
Posts: 1,169
Default 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  
Old December 18th 12, 12:36 AM posted to sci.astro
dlzc
external usenet poster
 
Posts: 1,426
Default 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  
Old December 18th 12, 01:24 AM posted to sci.astro
Lord Androcles, Zeroth Earl of Medway[_5_]
external usenet poster
 
Posts: 74
Default 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  
Old December 18th 12, 02:07 AM posted to sci.astro
Yousuf Khan[_2_]
external usenet poster
 
Posts: 1,686
Default 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  
Old December 18th 12, 05:21 PM posted to sci.astro
dlzc
external usenet poster
 
Posts: 1,426
Default 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
  #17  
Old December 22nd 12, 12:03 AM posted to sci.astro
Steve Willner
external usenet poster
 
Posts: 1,169
Default 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  
Old December 24th 12, 09:24 AM posted to sci.astro
Yousuf Khan[_2_]
external usenet poster
 
Posts: 1,686
Default 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  
Old December 24th 12, 09:35 AM posted to sci.astro
Yousuf Khan[_2_]
external usenet poster
 
Posts: 1,686
Default 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  
Old December 24th 12, 04:07 PM posted to sci.astro
dlzc
external usenet poster
 
Posts: 1,426
Default 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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