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north
2006-Aug-14, 11:49 PM
I've come to the conclusion that Einstein was right that A should = 0( A=O) the only reason that he changed his mind when his theory suggested or implied that the Universe was not static if the Universe is spatially homogeneous.( but is it?).

and further Hubble apparently found that the Universe is nonstatic.

however and this caught my interest, and I quote;

"cosmological constant

A constant( usually denoted A) that measures the curvature of an empty space devoid of gravitational fields.

In the real Universe, where gravitational fields exist throughout the whole space, this curvature would provide a tiny background(approx. 10-50 cm-2) to the total curvature, but its effects on the evolution of the Universe could be profound.( it goes on about Friedmann-Lemaitre model)".

it does not explain the NATURE of space.( properties of)

therefore the "cosmological constant" is based on an undefined QUALITY.

trinitree88
2006-Aug-15, 12:19 AM
I've come to the conclusion that Einstein was right that A should = 0( A=O) the only reason that he changed his mind when his theory suggested or implied that the Universe was not static if the Universe is spatially homogeneous.( but is it?).

and further Hubble apparently found that the Universe is nonstatic.

however and this caught my interest, and I quote;

"cosmological constant

A constant( usually denoted A) that measures the curvature of an empty space devoid of gravitational fields.

In the real Universe, where gravitational fields exist throughout the whole space, this curvature would provide a tiny background(approx. 10-50 cm-2) to the total curvature, but its effects on the evolution of the Universe could be profound.( it goes on about Friedmann-Lemaitre model)".

it does not explain the NATURE of space.( properties of)

therefore the "cosmological constant" is based on an undefined QUALITY.


NORTH. Many years ago...circa 1988, possibly spring 1987...I attended a lecture by Lawrence Abbott, then a professor of physics, or mathematics, at Brandeis University, Waltham, MA...."The Cosmological Constant"...at MIT's Physics Colloquiem, Thurs. Bldg. 10- rm.250 4:15. In it he defined a "missing" piece of gravitational theory using a combination of physics constants arranged in a configuration I had never seen.....being a lazy slug... I figured I'd photocopy his paper he mentioned...but never found it. It's in some conference proceedings published in Singapore (this sounds like a sci-fi movie). He mentioned an energy level of ~ 0.003 ev. I posted once on this I think to Peteshimmon. Check. I'm running out of time, and money. Good luck. Pete.

north
2006-Aug-15, 12:34 AM
Originally Posted by north
I've come to the conclusion that Einstein was right that A should = 0( A=O) the only reason that he changed his mind when his theory suggested or implied that the Universe was not static if the Universe is spatially homogeneous.( but is it?).

and further Hubble apparently found that the Universe is nonstatic.

however and this caught my interest, and I quote;

"cosmological constant

A constant( usually denoted A) that measures the curvature of an empty space devoid of gravitational fields.

In the real Universe, where gravitational fields exist throughout the whole space, this curvature would provide a tiny background(approx. 10-50 cm-2) to the total curvature, but its effects on the evolution of the Universe could be profound.( it goes on about Friedmann-Lemaitre model)".

it does not explain the NATURE of space.( properties of)

therefore the "cosmological constant" is based on an undefined QUALITY.


NORTH. Many years ago...circa 1988, possibly spring 1987...I attended a lecture by Lawrence Abbott, then a professor of physics, or mathematics, at Brandeis University, Waltham, MA...."The Cosmological Constant"...at MIT's Physics Colloquiem, Thurs. Bldg. 10- rm.250 4:15. In it he defined a "missing" piece of gravitational theory using a combination of physics constants arranged in a configuration I had never seen.....being a lazy slug... I figured I'd photocopy his paper he mentioned...but never found it. It's in some conference proceedings published in Singapore (this sounds like a sci-fi movie). He mentioned an energy level of ~ 0.003 ev. I posted once on this I think to Peteshimmon. Check. I'm running out of time, and money. Good luck. Pete.


I wish you could have just posted it here, at least the link!

as a result ~0.003 ev doesn't mean much yet.

but thanks anyway.

so are you/Lawrence suggesting that space is a form of energy? interesting.

turbo-1
2006-Aug-15, 01:12 AM
so are you/Lawrence suggesting that space is a form of energy? interesting.Space/vacuum is energy. Vacuum cannot be devoid of energy in our universe.

north
2006-Aug-15, 01:30 AM
Originally Posted by north
so are you/Lawrence suggesting that space is a form of energy? interesting.


Space/vacuum is energy.

how so? prove it.


Vacuum cannot be devoid of energy in our universe.

therefore there is no such thing as a pure/ absolute vacuum.

and therefore there is no such thing as a vacuum.

Cougar
2006-Aug-15, 01:48 AM
cosmological constant, is it true?
The concept of truth is encountered in mathematical logic, not so much in science doing its best to describe the nature we can observe.


I've come to the conclusion that Einstein was right that A should = 0( A=O) the only reason that he changed his mind when his theory suggested or implied that the Universe was not static if the Universe is spatially homogeneous.( but is it?).
This is a very poor "sentence." You must use periods when you start a new sentence. Your history is confused, so I have doubts about the underpinnings of your conclusion that lambda=0. Show that I'm wrong.


it does not explain the NATURE of space... therefore the "cosmological constant" [cc] is based on an undefined QUALITY.

Well, the "quality" of the cc is its effect of expanding space faster than one would expect if the expansion was just "coasting." Of course, there is certainly no consensus in the scientific community as to how space can do that. In addition, the cc is only one possible explanation for the observations, which are not yet precise enough to rule out a number of possibilities.

Nereid
2006-Aug-15, 02:12 AM
how so? prove it.



therefore there is no such thing as a pure/ absolute vacuum.

and therefore there is no such thing as a vacuum.What term do you use for what's in a particle accelerator, or the LIGO beam tubes (http://www.johnstonsarchive.net/relativity/ligoinfo.html), when the air is pumped out?

turbo-1
2006-Aug-15, 05:41 PM
north, I have tried to post an answer twice now, and I just can't seem to get it to "take". Fingers crossed for this one:

The vacuum contains the bulk of the mass-energy of the universe in the form of virtual particles, arising and annihilating in accordance with the Heisenberg uncertainty principle. In fact, if we do not assume an ultraviolet cutoff, the vacuum energy runs to infinity. While we can produce very hard vacuums, with very low concentrations of real particles, we cannot produce a vacuum devoid of virtual particles. What the particle physicist calls a vacuum is a bounded area containing very few real particles, but teeming with virtual ones.

north
2006-Aug-19, 02:00 AM
north, I have tried to post an answer twice now, and I just can't seem to get it to "take". Fingers crossed for this one:

The vacuum contains the bulk of the mass-energy of the universe in the form of virtual particles, arising and annihilating in accordance with the Heisenberg uncertainty principle.

what do mean by the above statement? don't mean to difficult just asking.



In fact, if we do not assume an ultraviolet cutoff, the vacuum energy runs to infinity.

this I do not understand. clearify please.


While we can produce very hard vacuums, with very low concentrations of real particles, we cannot produce a vacuum devoid of virtual particles.

as far as virtual particles are concerned are they real or assumed? because of the conservation of energy principle.

north
2006-Aug-19, 02:15 AM
What term do you use for what's in a particle accelerator, or the LIGO beam tubes (http://www.johnstonsarchive.net/relativity/ligoinfo.html), when the air is pumped out?

what I mean by vacuum, is a space completely devoid of any energy/matter and any form thereof, absolutely.

north
2006-Aug-19, 02:26 AM
Originally Posted by north
I've come to the conclusion that Einstein was right that A should = 0( A=O) the only reason that he changed his mind is when his theory suggested or implied that the Universe was not static if the Universe is spatially homogeneous.( but is it?).


This is a very poor "sentence." You must use periods when you start a new sentence. Your history is confused, so I have doubts about the underpinnings of your conclusion that lambda=0. Show that I'm wrong.

I got this info from my "Dictionary of Geophysics, Astrophysics and Astronomy"( Matzner, CRC press,ISBN # 0-8493-2891-8)


Well, the "quality" of the cc is its effect of expanding space faster than one would expect if the expansion was just "coasting." Of course, there is certainly no consensus in the scientific community as to how space can do that. In addition, the cc is only one possible explanation for the observations, which are not yet precise enough to rule out a number of possibilities.

hmmmm....

Nereid
2006-Aug-19, 02:33 AM
What term do you use for what's in a particle accelerator, or the LIGO beam tubes, when the air is pumped out?what I mean by vacuum, is a space completely devoid of any energy/matter and any form thereof, absolutely.So, what term do you use for what's in a particle accelerator, or the LIGO beam tubes, when the air is pumped out?

north
2006-Aug-19, 02:47 AM
Originally Posted by north
Quote:
Originally Posted by Nereid
What term do you use for what's in a particle accelerator, or the LIGO beam tubes, when the air is pumped out?

what I mean by vacuum, is a space completely devoid of any energy/matter and any form thereof, absolutely.


So, what term do you use for what's in a particle accelerator, or the LIGO beam tubes, when the air is pumped out?

I don't know. is there NO trace of energy/matter in these tubes? in any form?

Nereid
2006-Aug-19, 02:54 AM
I don't know.
[snip]So to what extent does your concept of 'vacuum' align with turbo-1's?

Unless and until there is a common basis for discussing something, at least with respect to the key terms used in that discussion, wouldn't the most accurate description of what's taking place be "talking past each other"?

north
2006-Aug-19, 03:19 AM
So to what extent does your concept of 'vacuum' align with turbo-1's?

Unless and until there is a common basis for discussing something, at least with respect to the key terms used in that discussion, wouldn't the most accurate description of what's taking place be "talking past each other"?

not really. turbo-1 explains that really in essence no such thing as "true vacuum". okay( chiral condensate, plasmas). no problem

but the problem of space being some sort of energy is yet to be addressed.

to equate the two, space/vacuum, as having an energy is erroneous.

again, as turbo-1 poined out a vacuum does have energy/matter within it but what does this have to do with space in and of its self having a energy/matter substance ?

Thanatos
2006-Aug-19, 10:11 AM
Vacuum fluctuations are a given in quantum theory. Do they have meaningful interactions with matter or energy in the observable universe? I think not. Photons and gravitons appear to be oblivious to any such effects [aside from GR fine tuning].

Bogie
2006-Aug-23, 12:52 PM
not really. turbo-1 explains that really in essence no such thing as "true vacuum". okay( chiral condensate, plasmas). no problem

but the problem of space being some sort of energy is yet to be addressed.

to equate the two, space/vacuum, as having an energy is erroneous.

again, as turbo-1 poined out a vacuum does have energy/matter within it but what does this have to do with space in and of its self having a energy/matter substance ?North, there is a concept of a vacuum; simply empty space. It is not a reality.

In reality, no vacuum complies with the concept. Near vacuums contain some particles. You might think that at some infinitesimal level, maybe between the “particles” that screw up the vacuum, that there really is some “empty” space, but there is no such place.

In theory, you say that there must be empty space between two lone particles in an otherwise perfect vacuum. Sorry, just the presence of one particle in an otherwise pure vacuum fills the entire vacuum, leaving no empty space.

It is hard to believe, but it is an efficient explanation of observed circumstances.

Virtual particles supposedly come into and out of existence everywhere, all the time, so if virtual particles really occur, they will appear and disappear even within a near vacuum, indicating that any space is composed of the energy to enable virtual particles.

Virtual particles are theoretical but the theory helps explain how actions at a distance, like gravity and magnetism, take place. Theoretically the virtual particles spew out from objects and interact with the spewed virtual particles from other objects.

Theory says that the spewed virtual particles don’t just knock objects around, but can attract objects to each other as well. You can get into some deep theory on this subject but 99% of us will either not understand it, or will be skeptical. I think the theory of virtual particles will eventually lead to a more detailed explanation of the spewing and the nature of the spewed particle in real English that will describe what is going on in terms that everyone will understand. Until then lets just let the geeks struggle with it. Maybe the spewed virtual particle isn’t coming into and out of existence at the instant of spewing; maybe the “virtual particles” already exist.

If the virtual particles actually are stable particles that exist in their own right, instead of coming into and out of existence, then space would be permeated with them, they would be infinitesimal, and their natural interactions with each other would form the structure of all “particles” that compose matter. Time will tell.