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“Hehe, sarge, time delays in posting stuff. Asynchronous discussions. Not very effective, but no worries. I’ll back up a bit and re-read. Enjoy your workout.”
“Ewker - walking and driving. I walk to the gym (in my house) to lift weights, then I ride to the gym to do aerobics. I take the long way.
The universe IS defined by what we observe.
When you're talking about "the observable universe", yes, of course. But for your argument to hold up you have to define the universe as such. We are talking about origins here. The universe will work under your "laws" if, and only if, you are allowed to define the universe as such. That is very convenient, but it also allows the loop hole of not having to explain anything beyond that. That is all relevant though because in order for your zero energy theory to hold, the universe must have come from "another" universe (observable, but not by us). We are talking about origins and therefore I will not afford you that luxury. You can only prove mathematically your point IF you allow the constraint to be that we go back as far back in time as you want, to a time which would not prove origins because of your zero energy loophole. You actually set yourself up for a catch-22.
The strong anthropic principle states that we see the universe the way it is because we exist. The universe could not unfold any other way than it has because we are here to observe it. "Why is the universe the way we see it?" The answer is that if it had been different, we would not be here!
You are combining two different definitions of the universe into one to make your point. On one hand, you are saying that the universe is only what we see, on the other, you are saying that the entire universe, including it's origins, are what we observe, even if those origins are outside the observable universe as your previous definition of a zero energy universe would require.
I think you are looking for what existed before time existed, assuming you accept that time has a beginning. With space and time inextricably linked it makes no sense to ask this question.
Time as we know it, yes. But then again, you have ignored the fact that we are talking about "origins". If we only define the universe as what is observable then you are going to have to go back and drop your zero energy theory. I'll leave that decision to you.
Scientists will admit ANYTHING is possible; hence the positivist model upon which modern science is built. It's not a matter of admitting anything. It's a matter of what predictions the model makes that can be measured and how useful the theory is at explaining things. Science is in a constant state of change because of it's very nature and it's willingness to adapt and be modified.
It's that very nature and willingness to do that has kept ID theory out of schools. /sarcasm font/ Would you also take black dwarf theory out of astro-physics classes?
PS - I'm off to the "other" gym now to do aerobics. I'm not sure if that's possible because the gym I'm in is observable, but the other gym is not from my vantage point.
last edited: 8/15/05 6:06:34 PM”
WARNING: LONG POST
“I am not saying the universe is only what we see. I am saying that the universe has certain properties because if it did not we would not exist. The fact that the universe unfolded as it did says something about it’s nature.
So, for example, we observe that spacetime is fairly flat. Hence we can rule out variations of Einstein's equations that lead to highly curved dimensions. Another example is that we observe 4 dimensions to spacetime, so we can rule out solutions to Einstein's equations that would yield more than 4 dimensions or at least solutions that would yield more than 4 that are not small and tightly curled upon themselves at a quantum level.
It’s not MY theory, it’s called the strong anthropic principle and it’s been around for a pretty long time. Read about it: http://en.wikipedia.org/wiki/Anthropic_principle
I didn’t know (as Wikipedia shows) that there are three versions of the theory. I only knew of the weak and the strong versions. I wasn’t aware of the “final anthropic principle”, which is very interesting and I have to think about for a few weeks. Learn something new every day!
Whichever you accept, however, it is undeniable that such a principle must be accepted as a truism since it can never be proven by it’s very nature … an “Antimony of Pure Reason” ala Kant. [Philosophy majors, that’s your queue to speak up!]
I brought this up because, as the Wikipedia article correctly states, proponents of the anthropic principal fall into the same camp as I think the intelligent design folks would. The proponents of the anthropic principle would claim that the universe has been “tweaked” in such a way that intelligent life could form and exist. So it sort of opens up another angle on this intelligent design topic that has been discussed (if you can call it discussion) in this thread.
I think (and I admit I an walking on very thin ice here) that intelligent design advocates would accept a version of the anthropic principal that says the universe is the way it is because the universe was optimized for it to be that way and that this optimization was done such that intelligent life could exist.
In contrast, the strong anthropic principal would say that this “optimization” is simply the laws of thermodynamics. The universe expresses a natural preference toward the most economical form of energy dissipation. The 2nd law of thermodynamics tells us that the entropy of our expanding universe increases with every action. The anthropic principal tells us that this preference will occur in such a way that the universe we exist in will be the result because if it worked out any other way we would not exist. So the laws of thermodynamics (which you claim conflict the cosmological model of the Big Bang) are in fact tightly wound into the theory and hence in total agreement with the theory by it's nature. They are it’s very underpinnings.
I’ll talk about the topic of zero energy in a future post, but Google “Vacuum energy” or read Wikipedia: http://en.wikipedia.org/wiki/Vacuum_energy and then we can talk about that. Sorry if you know this already. It would not be my intent to sound insulting.”
GOOD NEWS: RELATIVELY SHORT POST
“Get it? "Relatively" ...
Anyways ... by paragraph:
1) Of course, we agree that the universe has certain properties.
2) Wow, I'm not sure you can rule out Einstein's equations just because you can only observe 4 dimension, but ok, I'll bite.
4) Great! Congratulations!
5) Ok. Continue. (although I don't think the "reason" it's a truism is because it cannot be proven by it's nature, but please continue...
6) Agreed, except I don't think it's a "new" angle. It's the basic angle I've taken all along.
8) Well, yes, if you skip the "origins" part of our discussion and skip right to the nature part of the universe, but can we get back on topic please?
9) I am familiar with it, and am surprised you have ignored my points about it several times up to this point. I don't think I could have made those points without knowing what it is. I'll be waiting for your reply.
pitts - I don't think we got anywhere there except you defined a couple of things which I'm not sure needed to be defined. I hope we don't get off track here from the discussion. I'll wait for you other post (if you didn't post it while I was writing this). Thanks.”
“Gotta help me find the right post. I can't find the one you wanted me to respond to. Sorry. Give me a sentance from it or two.”
“A follow up post by me begins "When you're talking about "the observable universe", yes, of course."”
“Tilt thinks he was designed by a dummy.”
LONGER POST THAN THE LAST ONE
“Zero-energy universe as best I can ...
Think of a rock held above the earth. The rock has zero energy (it is at rest). As the rock falls it accelerates gaining positive kinetic energy as it falls. The energy the rock gains as it falls is balanced by the increasing negative gravitational energy as the rock approaches the Earth’s center. The total energy of the system is zero …that is the positive kinetic energy of the ball plus the negative energy of gravity equals zero which is the same as what the ball had when it started (at rest). This is very basic physics.
The universe works the same way. At the beginning of time (which is all the “big bang” is) vacuum energy created particle pairs whose positive energy exactly balanced out the negative gravitational energy they exerted on each other. So the total energy of the universe was zero and so it remains today.
What produced the vacuum energy before the expansion of the universe/beginning of time? Indeed it is quite possible for the energy to come from nothing (and this is NOT a violation of the 1st law of thermodynamics as I will explain) so long as the net energy is zero. Quantum theory and specifically the Heisenberg uncertainty principal provides a mechanism for the birth and death of virtual particle pairs that don’t violate the 1st law of thermodynamics. These are called “quantum fluctuations” and they have been observed in experiments. These quantum fluctuations occur all the time. Electrons and positrons, for example, are continuously and spontaneously being created and then annihilate each other everywhere all of the time. That’s why I attached the link on vacuum energy in my last post.
Of course you have to accept that time had a beginning which it clearly must. There must have been a point at which it is meaningless to ask, "What happened before this moment?" I don't think this is a point you would dispute.
The typical reason why evolution is bashed by critics based on thermodynamics is on the 2nd law. Honestly I was waiting to see if you went down this road, and who knows... perhaps you will. That said, the argument is that the 2nd law says that entropy (disorder) in a closed system must always increase. Evolution describes a process through which a system (like the Earth) actually becomes more ordered over time and not less ordered. Hence it appears to violate the 2nd law of thermodynamics. The problem here is that the 2nd law applies to a closed system which the Earth is not. The Earth has the sun as a source of energy. Hence energy is pumped into the Earth and energy can be used to make systems more ordered over time. So evolution doesn’t violate the 2nd law of thermodynamics.
You do this when you make ice cubes in your freezer. You pump energy into a compressor to remove heat energy (entropy) from the water to permit it to form ordered crystals (ice). The heat you remove goes into the air which increases the entropy of the air itself. So while you decrease the entropy of the water to make ice you increase the entropy of the air by making it warm. Water on it's own won't freeze from the tap. You have to apply energy to the system to make it happen.
I recognize you were talking about the 1st law as it relates to the beginning of time. I just wanted to point this out.
That said, what I was trying to point out in my last post was that all of this (intelligent design, evolution, cosmology, and thermodynamics) all tie back into the anthropic principal. So I was trying to tie this cosmology discussion to the original thread of intelligent design. It’s directly related through the anthropic principal because it relates to whether or not the universe is the way it is because it was “tuned” or if that “tuning” is just the laws of thermodynamics and nothing else is needed.
I tend to accept that the universe has certain properties defined by the laws of thermodynamics that define how it prefers to use energy that have produced a universe where intelligent life can exist. Hence the anthropic principal allows me to select a subset of solutions to Einstein’s Equations (not throw out the equations themselves!) that resemble the universe in which I could exist to ask questions about its nature and to toss out the ones that don’t match observations. It’s a weeding out process since many of the solutions to the Einstein Equations are very complex, have many dimensions, or are very highly curved … which don’t match observations.
Sorry for the long posts. This is a favorite topic of mine. I have a friend that I talk about this stuff with. I didn’t think he was interested and one day I joked about the Heisenberg Uncertainty Principal (a geek joke from college I should not have told since 99.9% of the people I know wouldn’t get it). I had to explain myself and little did I know that I created a monster. He started reading and one day came back with lots of questions about superstring theory. Go figure! It’s nice to have someone to chat with about deep topics like this.”
no more cosmology for tonight
“we should save this discussion for a campfire and a bottle of jack daniels.
i am going to get my guitar, play some Neil Young, and get piss drunk ... report to work with a hangover tomorrow.
“pitts - Can I just preface by saying I appreciate the definitions, but they're not necessary unless you have a personal spin on the definition of them that I wouldn't be aware of. I guess in a way you do, because with your zero energy definition as it relates to the Heisenberg principle, you seem to think matter is literally created. The problem with that slant is that (1) matter in a science experiment that is "created" could easily have come from another part of the existing universe, and (2) pre BigBang, something would have had to had existed in order for a particle (which in and of itself had to exist in order to fluctuate) to have "jumped" into "nothing", there had to be time and matter already in place, otherwise you ARE violating laws 1 and 2.
I realize how the 2nd law is typically used to refute evolution, but I am reserving that for another discussion. It applies to this discussion if you are willing to concede that your mathematics only work if you are allowed to ignore physical laws that have been documented by science.
May I suggest that you don't confuse the definition of "zero energy" of an existing universe (ours) with a non-existing universe about to be "created". The definition ONLY applies if you already have matter and time established, which you didn't at our "origin". I think you're saying, if I understand you correctly, that you're claiming that due to the uncertainty principle that matter is in fact created from nowhere to nowhere, but if you would look at what the uncertainty priniciple involves you would see that it does not necessarily allow that. It's like your sun example when talking about a "closed" vs. "open" system. The sun is the source of matter and energy for the earth, just like particles observed during the Heisenberg experiments have a source.”
“Interesting discourse, Pitts. It's good to have at least one person around who actually has a little knowledge about all this.”
“How would you know if it's interesting if you know nothing about it Mutt, which is obvious. Could be just a bunch of crap for all you know. Maybe crap is interesting to you.”
“I like you Sarge. You're a real pistol! Your skill in aggressing is to be admired. I'd say you have me beat in that respect, hands down.”
“This issue's really not my bag but I found this book for like $10 so I bought it. I hope to read it with a balanced and open mind.
“(1) matter in a science experiment that is "created" could easily have come from another part of the existing universe, and
In classical physics “nothing” is a featureless piece of space. That is to say it has no properties and specifically it has minimal energy. This state of minimal energy is called a “ground state” in Quantum Mechanics.
The Heisenberg Principle says that we can’t precisely know what the ground state actually is. Hence it gives rise to quantum fluctuations in the ground state (the probability that the ground state will have a certain value). The ramification of this is that “nothing” is in fact not featureless as classical physics would suggest. In fact it is the quantum mechanical state in which no field quanta are excited, that is, no particles are present. In such a quantum field particle pairs (electrons and positrons, for example) spontaneously are created and subsequently annihilate in accordance with the Heisenberg Principle as applied to the ground state energy. The Heisenberg Principle, in essence, provides a timeline within which you can’t tell if the laws of thermodynamics have been broken or not because of uncertainty in the ground state. The timeframe for this activity is called the Planck Time and is related to the speed of light and Planck’s Constant. The creation/annihilation gives rise to a small (counterintuitive) negative energy density which exactly balances the total energy of the system.
I am not making this up and it’s not a definition. Ground state fluctuations and negative energy densities are an observed and measured phenomena that are predicted by quantum mechanics. What may appear as a definition to you is actually the result of a lot of math that makes predictions that have been labeled. The math can’t possible be conveyed in this forum as I know you are aware and I think stated earlier.
(2) pre BigBang, something would have had to had existed in order for a particle (which in and of itself had to exist in order to fluctuate) to have "jumped" into "nothing", there had to be time and matter already in place, otherwise you ARE violating laws 1 and 2.
In terms of this second point, I thought that you accepted that time had a beginning. The classical view is that time represents a constant that stretches on into infinity into the past and future independent of space. We know now that this is not possible and that there was a moment where it made no sense to ask, “What occurred before now?” In your statement you claimed “there had to be time and matter already in place” which is a contradiction to the known reality that time had a beginning. In fact time did not exist prior to the Big Bang and hence it is meaningless to ask what existed before this moment because there was no “before this moment”. I think your argument is circular reasoning, assuming you accept that time had a beginning.
last edited: 8/16/05 12:07:43 PM”
“(1) I am not making this up and it’s not a definition. Ground state fluctuations and negative energy densities are an observed and measured phenomena that are predicted by quantum mechanics.
But only in an existing universe.
You are ignoring, and have been ignoring, that this phenomena has not been measured, nor predicted, in a non-existent universe. I understand what your theory is, but your theory is an unscientific one, and NOBODY has shown otherwise. There is NO EVIDENCE, mathematical or otherwise, that quantum fluctuations can take place inside of a non-existent system.
(Regarding definitions - I was referring to your defintion of zero-energy universe.)
(2) I think if you read my response (1) above and then reread my pre BigBang dialog that you will see that there is no circular reasoning. You made some incorrect presumptions in your reply which are evident in my reply to (1). To further clarify, time did have a beginning, it was the creation of the universe. You seem to be assuming that I am accepting your premise that the universe (entire, not observable) is a zero-energy system. I am not accepting that for the reasons above.”
“But only in an existing universe
Incorrect. The concept of ground state fluctuation is not tied to the universe. It’s an amazing implication about the nature of “nothing” that is derived from the Heisenberg Uncertainty Principal.
Furthermore, ground state fluctuations are a phenomena, not a theory. Quantum Theory predicts ground state fluctuations, virtual particle pair creation/annihilation and the existence of negative energy densities. These have all been observed and agree with theory. It’s a substantial validation of Quantum Theory and is well documented.
The theory says what it says about ground state energies. It then makes predictions about what we should see in our universe. So while it’s true that our observations and measurements take place in this universe, these observations and measurements are only a point of validation for Quantum Theory and are not a requirement of the theory itself.
time did have a beginning, it was the creation of the universe
... and this event is called the Big Bang. The Big Bang is the beginning of time and space otherwise known as the creation of the universe. So we both agree that this event took place. I may call it the Big Bang and you may call it “the creation of the universe”. It’s the same thing. It’s the first point in time at which there is no past.
Hence it makes no sense for you to ask " what happened before creation" since time "before creation" does not exist. Your talk of "pre BigBang" is meaningless because there is no time that is "pre BigBang". The Big Bang is when time was created in a fashion inextricably liked to space. As I said earlier, it’s the first point in time at which there is no past.
I see the major difference between our positions as our interpretation of the anthropic principal. So I think it’s you that are actually ignoring what I am saying. As I said earlier, you can reach your view of the creation event by stating an anthropic principal that says that the universe we live in is the way it is because it was tuned to support the formation of intelligent life. My version says that the universe is the way it is because the universe has certain properties that lend itself to the creation of intelligent life and that these properties are governed by the universes tendency to use energy in the most efficient manner possible (the 1st and 2nd law of thermodynamics).
Which one is right and which is wrong? A positivist (as I am) does not ask this question. I do know that the theory I currently use in my understanding of the universe is very useful since it makes all sorts of predictions that we can look for or have already seen. Also, it doesn’t require some magic process or “fudge factor” such as Einstein’s Cosmological Constant or the concept of “tuning” in Intelligent Design.”
You claim that quantum fluctuation is not tied to existing matter.
I believe you are wrong. Please show me an experiment where it shows otherwise.
And I am not ignoring what you are saying. To the contrary, I read your post as you are ignoring what I am saying. The difference is that you believe that a zero-energy universe can be created without a pre-existing universe and I don't.
Again, show me.”
“The theory that predicts quantum fluctuations, Quantum Theory and specifically the Heisenberg Uncertainty Principal, is not tied to existing matter. I am not sure what you are asking me to show you.
A validation that ground state fluctuations exist is the Casimir effect: http://en.wikipedia.org/wiki/Casimir_effect
Taken from Wikipedia above:
The Casimir effect is caused by the fact that space is filled with vacuum fluctuations, virtual particle-antiparticle pairs that continually form out of nothing and then vanish back into nothing an instant later.
Physical Review Online describes the experiment in detail: http://prola.aps.org/abstract/PRL/v78/i1/p5_1
Quantum fluctuations are a prediction that is made by the Heisenberg Uncertainty Principal which is part of Quantum Theory. Quantum Theory defines “nothing” as a ground state. A ground state is the state for which there is no matter. The Heisenberg Uncertainty Principal says that you can’t actually know for sure the exact value of the ground state. Hence there exists a quantum field within which particle/antiparticle pairs are spontaneously created and annihilate each other on a time scale less than the Planck Time. This process creates a slight negative energy density which is measured in the Casimir effect. It’s validation that Quantum Theory’s prediction about the nature of “nothing” is correct.
Show me something that says otherwise.”
“The Casimir effect is caused by the fact that space is filled with vacuum fluctuations, virtual particle-antiparticle pairs that continually form out of nothing and then vanish back into nothing an instant later.
Let me say this again slowly ...
The - Casimir - effect - is - caused - by - the - fact - that - space - is - filled - with - vacuum - fluctuations, ...
Did you catch it that time?
I want to (again) point out 2 things.
1) There is NO evidence, including from your previous post, that you can have quantum fluctuations created out of nothingness. There is no math to support this. We have matter/time all around us, where these experiments are taking place.
2) These experiments REQUIRE space to exist in the first place, that is, time/matter, in order to carry out the experiment.
Please show me any mathematical proof/evidence/conjecture that you can have quantum fluctuations without universal preexisting "foam".
last edited: 8/16/05 2:18:26 PM”
“I'll have to post more this evening, but for now I'll say that the term "preexisting" is confusing and I don't even know what "foam" is in this context. If you accept that time has a beginning then saying something (anything) preexisted is a contradiction.
So I can’t prove to you that quantum fluctuations occurred prior to the Big Bang any more than you can claim that “preexisting foam” existed. I will say that if you believe that time had a beginning then it’s meaningless to refer to something as “preexisting” since time did not exist prior to the Big Bang. At the beginning of time there was no “pre” to “preexisting”. That’s what is meant by “beginning”. With time and space interwoven it doesn’t make sense to talk about matter existing prior to time.
This doesn’t mean that quantum fluctuations could not have started the sequence. Quantum Fluctuations are predicted by the Heisenberg Uncertainty Principal which states that there is an uncertainty relationship between non-commuting operators. It isn’t tied to the nature of space and time. So while your theory of preexisting foam contradicts the fact that time had a beginning, my theory does not. That is, your theory needs to be modified while so far you have said nothing to convince me that mine does.
I say “my theory” but all this isn’t mine. It’s all basic physics that was put down before I was born with the exception of some of the cosmology stuff Stephen Hawking did (most notably the application of the anthropic principal to the Einstein Equations).”
“Quantum fluctuations are alive and well in my bowels. Don't make me prove it.
And for being a reknowned cosmetologist, Stephen Hawking has really bad hair.”
“pitts - There is something very fundamental that you aren't grasping here, and I will attempt in this post to correct that.
First, since you questioned "preexisting foam", I'll start with that. I understand you come from a physics only background and haven't studied much of cosmology, so here you're going to have to merge the two sciences in order to understand this concept.
Let's start with "foam". By "foam", I'm talking about the vacuum/space that a particle "fluctuates" into. That is, if you study quantum fluctuation you'll see that the particles you mentioned appear "somewhere". That "somewhere" is termed "foam". Like all of this, it's theoretical, regardless of the amount mathematics supporting it. Suffice it to say it's a basic physical part of the principle you have been repeating. In a nutshell, we're talking about the "observable universe". To bring it all together: Quantum fluctuations have been observed when unforseen matter/anti-matter "appears" in the observable universe, and then disappears. The basic theory you're talking about presupposes that the matter decides to stay around for awhile unlike it's brothers and sisters.
Now let's talk about "preexisting foam". When I mentioned "preexisting foam", I was referring to the known observable universe. Therefore, that pretty much erases about 50% of your above post due to a correction on your premise. A preexisting "target" (including time/matter) has to be there for quantum fluctuation to take place. Also, a preexisting "source" (including time/matter) has to be there for quantum fluctuation to take place. Even if you disagree with the "target" requirement (because you believe space/time is created via the fluctutation), you still must have the "source" requirement.
Regarding "preexisting" as a contradiction: Setting aside the "preexisting foam" talk for a moment ... You cannot have a quantum fluctuation without preexisting matter - somewhere. I believe this is where we disagree, correct me if I'm wrong. If you do believe that you can have quantum fluctuation without preexisting matter anywhere within "range" of the target universe, I'm requesting a study that proves that. (this is no different than my previous request) I believe this is CRUCIAL to your argument, yet I have not seen anything to support your claim.
If you need further clarification, please ask. Your presumptions have been somewhat off, so please don't assume anything, just ask for clarification. Thanks.
last edited: 8/16/05 5:00:44 PM”
“I sure hope there won't be a test on all this afterwards. If there is then please let it be true/false or multiple choice.”
“what the heck? - I had to sit down after reading this stuff - made my head hurt...
and made me even happier that I send the kidlets to private school...”
“I'll take preexisting foam for $100, Alex.”
“Anyone else craving crackers and a big bowl of primordial soup? You gotta eat it quick because those little fishes keep trying to crawl out onto your plate. *BAM!* there goes another.”
“He's on a roll folks! Even an outside force can't stop him now!”
I gotta do house stuff so I'll play later.”
“I just got this last comment:
“He's on a roll folks! Even an outside force can't stop him now!”
If that last comment was directed at me I can't say I feel like I deserved it. I have been respectful and engaged in what I thought was an entertaining dialogue. If the objective of this isn't the dialog but humiliation than I definitly don't want to play. I don't need to put down other people to feel good about myself and I certainly don't need to hang out with others that do.”
i do. unfortuneately, many do not. many christians believe the world was literally created in 6 days. not metaphorically, not s-rges pet peeve sense, but literally.”
“If your definition of "all-powerful" is something greater than that, you have very high expectations
i dont necessarily believe anything or anyone is all-powerful”
“i dont necessarily believe anything or anyone is all-powerful
Whether God exists or not (or is all powerful or not) is certainly not dependent upon our belief one way or the other. Likewise if I do not believe in gravity, it doesn't matter either way, gravity will still be gravity regardless of how I personally feel about it.
Beliefs are funny things. Not ha ha! funny, but just funny. If there's one thing I wouldn't want to be absolute "sure" of in this life, that would be thoughts about God and why our lives exist in the first place.”
“Whether God exists or not (or is all powerful or not) is certainly not dependent upon our belief one way or the other.
im not suggesting gods existence is dependent upon my belief”
“Um Pitts. I was talking about Buck, who was cracking jokes.”
“If you'd lighten up Pitts, you wouldn't fly off the handle as much when someone pushes you.
(It's Newton's 2nd Law of Motion, the Buck comment was his 1st Law of Motion. Ha Ha. Man, the more we talk serious about this stuff, the more it makes me crack stupid jokes. ... Get it? (Think Newton again.))
last edited: 8/16/05 8:00:27 PM”
“I want one of these....
“I just got back from my weekly meeting with the Boy Scouts. I need a shot of cosmic foam ... on the rocks.
Lighten up! I have a pretty thick skin. I am just tired like a lot of guys with a job, kids, and too much responsibility. I need to get out and go hiking. I do welcome the discussion. I abandoned astrophysics almost a decade ago for reasons that I'll only talk about over a beer. It was a great career move, but one can't ever get away from the material. It's too much fun.
I am intrigued that you would bring foam into this discussion. I have honestly not spent a lot of time on this topic because I haven't really studied quantum gravity in any great detail.
Quantum Foam is an approach I have never been convinced of. I have always felt that applying quantum fluctuations to spacetime and gravity is guesswork at best. I would feel more comfortable with the concept if the implication of foam (that gravity is a quantum field) could be measured. The size of the Planck Length implies to me that the likelihood of this happening is pretty slim in my lifetime. These are very minute effects and they are based on a structure for spacetime that is highly speculative.
That said, I know I read somewhere there were experiments to look for the structure in spacetime that foam predicts should exist. I still consider it a theory that has yet to prove itself. Actually, I am really interested in this now and if you know of anything good I can read on the topic I would sincerely appreciate the reference ... specifically on proposed experiments to probe for quantum foam structure.
I still don’t get the “preexisting” part of your foam discussion but I’ll set it aside.
Regarding "preexisting" as a contradiction: Setting aside the "preexisting foam" talk for a moment ... You cannot have a quantum fluctuation without preexisting matter - somewhere. I believe this is where we disagree, correct me if I'm wrong.
Yes, I think we disagree on this point. Quantum fluctuations are based on the uncertainty principle applied to the ground state which is the lowest state of energy where there is no matter or energy. So the existence of quantum fluctuations is basically established in theory in the ground state where there is no matter. We have already established that the effects of quantum fluctuations (negative energy densities) can be measured in the lab. We aren’t arguing that quantum fluctuations exist in ground state energies, just the conditions under which they exist.
At least I think that is what we are tossing back and forth now. I lost track.
I am going to go play the guitar and put down a few cold ones. G'nte dude.”
“Forgive me pitts but I just don't see how we can go any further until we get over this one point.
I honestly am running out of ways to say this. Forgive me if I repeat myself, but I'm not certain you're really trying to answer this question. I know I'm probably not explaining it the best, but it's not that hard to understand I feel, so I don't know why this isn't being addressed.
In order for a particle to succumb to quantum fluctuation, it must first exist. You seem to believe that it does not.
My understanding is that the reason you think it does not have to previously exist is because you think that we have been able to demonstrate quantum fluctuation, in a zero energy environment where a particle is created out of nowhere. Is this correct?
The problem is that hasn't happened. First of all, we have not simulated, even mathematically, an environment where a particle appeared into, what was a second ago, absolutely nothing. Secondly, in the lab, we cannot do this logistically anyways. It almost sounds to me that you are allowing the pre-existence of matter in order to generate (create) the very first "piece" of our universe. That, by definition, would not be the "origin" of the universe. You would have to go back further, to the very first created particle, in order to do that.
When I've said something similar to this before you brought up that "time" was not in existence before the Big Bang. Ok, let's say that's true, (even though I don't think it is if you follow your logic), but even if it were true then you would need to explain how you can have matter without time, because you still have to explain that very "first" particle which was used to "seed" our universe. I can barely write this though because of course there would have had to of been "time" for that to have happened.
I'm sorry pitts, but I don't know how else to say this. I think you're making my question harder than it is. It's a request for you to explain the foundation of your belief that our universe was born out of absolutely, postively, nothing at all.”
“I guess we are agreeing that we disagree. At least that's something.
The statement that the universe has zero total energy is just General Relativities way of saying the universe is stable. And since the total energy must be a constant (the 1st law of thermodynamics) then if it is zero now it was zero at the beginning of time.
Look, there is a reason the Big Bang Theory is called a theory. It's a way to model the creation of the universe. In a zero energy model the positive energies of mass offset the negative potential energy of gravity to yield a zero total energy and you get a universe that can spontaneously be created from “nothing”. That’s not just an ordinary “nothing”. This “nothing” would be the quantum vacuum upon which spacetime is imprinted (not contained within) and where a sea of virtual particle pairs pop in and out of existence “stealing” energy for less than a Planck Time and then returning it.
Is it "proven"? No, of course not. It is a theory that explains certain things we can see and also fits to our understanding of the laws of the physical universe. So to date it is a good model that has proven itself useful. To date I have not seen one better, but I admit that's not saying much.
... and it doesn't violate the laws of thermodynamics. In fact it intentionally preserves them. That was the start of this discussion.
last edited: 8/17/05 12:25:23 AM”
“pitts - I think we're getting somewhere. I will answer this tonight sometime. I don't want to answer hastily and risk perpetuating the round and round we are doing on this key aspect. Thanks!”
“its a crash! bang! big bang thang!”
“pitts - Give me a rain check? I'm going to bed early tonight. Time is relative anyways. I'll respond yesterday.”
“I'll be out this weekend so if you post a follow-up in the dialogue I won't be able to reply until Monday.”
“Evangelical Scientists Refute Gravity With New ‘Intelligent Falling’ Theory
KANSAS CITY, KS—As the debate over the teaching of evolution in public schools continues, a new controversy over the science curriculum arose Monday in this embattled Midwestern state. Scientists from the Evangelical Center For Faith-Based Reasoning are now asserting that the long-held "theory of gravity" is flawed, and they have responded to it with a new theory of Intelligent Falling.
"Things fall not because they are acted upon by some gravitational force, but because a higher intelligence, 'God' if you will, is pushing them down," said Gabriel Burdett, who holds degrees in education, applied Scripture, and physics from Oral Roberts University.
Evangelical Scientists Refute Gravity With New ‘Intelligent Falling’ Theory”
“The Onion is one of the best deals on the web! That is the funniest thing I have read this week, which is actually a pretty sad statement.”
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