Lambda-CDM theory - Woo or not?

temporalillusion · Feb 28, 2009

What do you mean I have zero dollars?? Look at all this money in my bank account!

(Hides credit cards)

Michael Mozina · Feb 28, 2009

Perpetual Student said:
I am not familiar enough with the physics involved to comment on the concept of negative energy from the perspective of cosmology. However, in general, the concept of any quantity in nature being negative is one of convention from the perspective of the mathematics used. It all depends on where one puts zero. Negative points on the real line are just as valid as positive points. Similarly, any quantity that can be increased or decreased can have a negative value at some point, which will depend on where one assigns zero. It's that simple.
I can place an object on a table and decide to assign its gravitational potential energy at zero. If I raise it a few feet I can now decide it has a positive energy . If I lower it under the table it will now have a negative energy (in my coordinate system). I have no doubt that valid results can be obtained in doing physics using this convention. The fact that the energy is negative under the table has no mystical meaning; it's merely a way of doing the math.

Even if one arbitrarily sets things to zero, an accelerating physical universe full of mass and energy cannot have zero energy.

Michael Mozina · Feb 28, 2009

DeiRenDopa said:
IOW, there is an additional MM criterion for judging whether something (in cosmology) is scientific woo or not, namely, some (implied) character flaw of Guth (and any others who had a hand in developing the concept of inflation).

This seems to be the only meaningful part of your post worth responding to.

As I have *repeatedly* explained to you now, Guth did what everyone does. He came up with an idea. I don't blame him for being "creative". He didn't even turn his own theory into the dogma it has now become. There is no point in blaming one man for the sins of an entire industry. I simply noted where the idea came from, I didn't condemn Guth personally or professionally.

What I condemn is the fact your turned his postdicted formula into a dogma that now excludes other theories of cosmology that are not "postdicted" from exactly the same "interpretation" of redshift data. I condemn the fact you can't demonstrate that inflation and DE exist in nature or have any affect on nature. Guth didn't stick a gun to anyone's head and make them accept his theories. The mainstream did that themselves.

DeiRenDopa · Feb 28, 2009

Michael Mozina said:
This seems to be the only meaningful part of your post worth responding to.

As I have *repeatedly* explained to you now, Guth did what everyone does. He came up with an idea. I don't blame him for being "creative". He didn't even turn his own theory into the dogma it has now become. There is no point in blaming one man for the sins of an entire industry. I simply noted where the idea came from, I didn't condemn Guth personally or professionally.

That's good to know; thanks for the clarification.

What I condemn is the fact your turned his postdicted formula into a dogma that now excludes other theories of cosmology that are not "postdicted" from exactly the same "interpretation" of redshift data. I condemn the fact you can't demonstrate that inflation and DE exist in nature or have any affect on nature. Guth didn't stick a gun to anyone's head and make them accept his theories. The mainstream did that themselves.

(bold added)

I think this is another Lather, Wash, Rinse, Repeat cycle ...

The demonstrations were made in page 1 of this thread, and in the WMAP team paper I cited (among other places).

Of course, if one applies the MM criterion for acceptability, then it would seem that such "demonstrations" have not, in fact, been made ... at least for inflation (for DE it depends on what you mean; in at least two meanings, they have).

In my next post, I'll bump a recent post of mine addressed to you that has not been answered yet; your answer may go some way to clarifying the extent to which your criteria are empirical, consistent, and useful.

DeiRenDopa · Feb 28, 2009

DeiRenDopa said:
Michael Mozina said:

[...]

Well, lets see what they have planned:

A. Prospective Additional Probes of Dark Energy

1. Galaxy Clusters (Number Density, Clustering and Their Evolution) The abundance and clustering of galaxy clusters is another promising technique, and has previously been considered by the DETF [12]. There are many means of identifying and measuring galaxy clusters; the main source of uncertainty in future applications of this method will be in determining the relation of the selection function and observables to the underlying mass of the clusters.

Click to expand...

Nope. It sounds like another "point at the sky and add math" exercises and it sounds pretty darn wasteful IMO. Nobody can empirically verify any of the presumed properties of "dark energy" by looking at the sky anymore than this can be done with "inflation". You're just fudging the numbers of mythical entities to fit observation and not you'd like to waste my tax payer money on *another* point at the sky routine with *zip* in the way of a real *control mechanism*.

Click to expand...

Just so that I don't misunderstand ...

You seem to be saying that it is impossible, under any circumstances whatsoever, for something to be discovered 'in nature' from astronomical observations which later - maybe even decades or centuries later - becomes testable/verifiable/whatever in labs in controlled experiments; are you? And irrespective of whether a direct line from the astronomical observations to the controlled experiments can be established or not?

To make this concrete: at least one element (helium) was first discovered in the spectrum of the Sun; later - ~a quarter of a century later - it was found in rocks here on Earth. By your criteria for assessing (astrophysics, in this case) scientific woo, helium did not exist until 1895, and all scientific work - by astronomers, chemists, geologists, etc - until then, on helium, should have received no MM-approved funding, as it would have been a clear-cut case of woo.

Did I get it right?

If you and a team had this much money at your disposal, how would you suggest it be spent, MM? Non-negotiable requirement: the money must be spent on research into "Dark Energy".

Click to expand...

I'd invest my money in PC/EU theory research and help you explain solar wind acceleration and coronal loops and stuff that has an affect on us here on Earth. Once you finally "get it" that EM fields exist in space, it probably wouldn't be much of a leap of faith to assume that any "acceleration" of a mostly plasma universe would be due to EM fields rather than some mythical fudge factor you stuffed into inflation theory to keep it alive.

Honestly, that has to be the most pointless waste of money I can think of, and in this economy it irks me that you would *waste* my tax money like that and try to pass it off as an "experiment". There are no control mechanisms. How about doing something *USEFUL* with my money like explaining solar wind acceleration? Birkeland could set you straight of course, but then *you* would have to do some reading.

Click to expand...

Okey, dokey, ...

Follow-on question then: do I understand that you are completely and totally convinced that the only possible explanation/accounting of the various "DE" observations is "EM fields" or "electricity" or "electrical discharges" (or some such thing)? That it is utterly impossible for the "DE" observations to turn out to be some subtle combination of selection effects, stellar evolution, misapplication of GR, and downright bad luck (to make up one example)?

Further, that, in the unlikely event that a full appreciation of the nature of DE, obtained by research such as that described in the paper, leads - directly or indirectly - to something really, really, really useful (a way to greatly improve the efficiency of fusion reactors perhaps), you will still declare the research to have been "the most pointless waste of money I can think of"?

Bump ... as promised.

Dancing David · Feb 28, 2009

Michael Mozina said:
It really has nothing to do with "PC stuff" per se. Your theory should stand on it's own merits regardless of the validity of any other theory.

Considering that you cherry pick evidence it is ahrd to talk to you. When you want to stop playing semantic, it would be easier.

It is you that have no empirical data to demonstrate that inflation or DE have any effect on anything in nature.

You have yet to demonstrate a theory that explains the 'cosmological' redshift is something else. Until you do so, there is the redshift, there is the apparent acceleartion in the redshift. One theory is that dark energy drives teh acceleartion.

It is all about explaining data, all theories are just abstractions.

Again, it is irrelevant what I might personally prefer in terms of cosmology theories, it is you that must demonstrate your case via empirical physics.

You ar ethe only one who says observation of objects at a distance is not empirical.

It's not my fault you chose to put your faith in a dead deity that has no effect on nature today. It was your choice to accept that weird idea, not mine.

I don't care, it is a theory that potentialy explains the data, whena better theory comes along then that theory will prevail.

You are the one with the hang up.

Actually, it's you that are left with only philosophy in the final analysis, because there is no empirical justification for you faith.

yet you accept the existance of electrons and neutron, neither of which can be observed any more directly than the CMB or redshift.

You have a double standard. Your objection to the BBe is philosophical.

It's all an arbitrary curve fitting exercise with math and somehow you think the universe has zero energy!

I don't understand GR enough to derive the equations. But it does make sense.
If objects are drawn together by an arbitrary force, then that is some form of energy.

I sort of understand why they call it negative.

You are hung up on words that is for sure.

If they called it potrezbie energy, it would not change the concept.

So the contracting energy of gravity might balance other forms of energy.

So what?

It is just a thoery.

I mean this is indeed only a philosophical argument in the end, because you don't have a physical leg to stand on in the realm of empirical physics where energy surrounds you and blows right through you.

Sure, whatever, you get all bent out of shape over words, this is another one.

So the potrezebie energy of gravity might balance the positive enrgy in the universe, so what?

If you folks were creationists, you would be a trifecta alright. According to your theory.,

1) There is no energy in the universe

You so funny. That is not what i or anyone said, the statement was that the potrezebie energy of gravity might negate the others.

2) Inflation and dark evil energies abound

Inflation is a possibility, you have some hang up with it. So? When another theory counters the same data, it will prevail.
dark energy the same, words are words.

Whoopie!

3) The inflation deity created the superluminal heavens and the earth and then rested.

You want to say that, fine. Whatever.

The mechanisms cannot 'contradict themselves', they work in a lab.

Okay I can't wait.

Negative electrons move from the negative sun to the positive heliosphere.
They drag along the positive ions but aren't the PI repeled by the positive heliosphere.
Should be fun to learn about.

I'll go back to that discussion when I'm done with this one, but my time is not unlimited and I'm still catching up on reading materials from Tim and from DRD. I've learned it's necessary at times to pick my battles and this seems to be the first necessary topic of conversation. I can't even really get into the "physics" until you folks start to accept that we live inside a *positive energy environment".

I can't wait to see how the positive ions have enough momentum to overcome the same force that draws the electrons towards the heliosphere.

I await learning.

However i expect to to be smart enough to know you contradicted yourself and so you will never respond.

Tim Thompson · Feb 28, 2009

Not to Worry

Skwinty said:
Why do arXiv approve papers like this for publication if they are so erroneous.

arXiv, until a couple of years ago, did not approve papers at all. Anybody could upload anything, and that is still pretty close to the way they operate. It is not a peer reviewed archive. But eventually they did pull a paper off the server, written by creationist "cosmologist" Robert Gentry, who claims a highly non-standard interpretation of cosmological redshift. Evidently it was so bad that not even arXiv, which is run by the Cornell University Library, could stand it. So Gentry sued Cornell. I don't know what the eventual settlement was, but now any paper on the server has to be submitted by, or sponsored by, an author approved by the arXiv management, but that list of sponsoring authors probably includes just about everybody except Gentry. So it is still very liberal, and as a rule content is not considered at all except that it should be at least relevant to the topic. You could probably get a paper on arXiv if you really wanted to.

Skwinty said:
http://arxiv.org/ftp/physics/papers/0511/0511178.pdf
ABSTRACT:
Although the Universe is far from understood, we are fairly confident about some key features: Special Relativity (SR) describes the kinematics of inertial frames; General Relativity (GR) explains gravitation; the Universe had a beginning in time and has been expanding since. Nevertheless it is quite difficult to see the ‘big picture’, although the idea of applying GR to the entire Universe has been very successful with a model emerging that is consistent with observation. One unpleasant feature of the model is that cosmological photons appear not to conserve energy, and the only explanation forthcoming is the claim that GR is exempt from the principle of energy conservation. It is demonstrated here that cosmological observations may legitimately be projected onto flat spacetime and can then be treated Special Relativistically, whereupon energy conservation is restored. This is not to say that the concordance General Relativistic cosmological model is incorrect, just that in observational terms there is no energy conservation anomaly.

This looks correct to me, with the caveat that general relativity is rather far removed from my own areas of expertise. The problem is that general relativity conserves energy for all isolated or local systems, but does not conserve energy globally. Here is how Edward Harrison says it:

"The conservation-of-energy principle serves us well in all sciences except cosmology. In bound regions that do not expand with the universe (because they are dense compared with the average density of the universe), we can trace the cascade and interplay of energy in its multitudinous forms and claim that it is conserved. But in the universe as a whole it is not conserved. The total energy decreases in an expanding universe and increases in a contracting universe. Where does energy go in an expanding universe? And where does it come from in a contracting universe? The answer is nowhere, because in the cosmos, energy is not conserved."
Cosmology: The Science of the Universe; Edward Harrison, Cambridge University Press 2000, 2nd edition; page 349.

Harrison's interpretation appears to be the standard, with which the general relativity texts I have seen commonly agree on. The technical details are perhaps best revealed in the book Spacetime and Geometry: An Introduction to General Relativity by Sean M. Carroll (the book is an expanded version of his Lecture Notes on General Relativity which are downloadable as PostScript or PDF). He points out that the integral of the energy density of the universe is not conserved ("Clearly, in an expanding universe, the energy-momentum tensor is defined on a background that changes with time; therefore, there is no reason to believe that the energy should be conserved" - Sean Carroll). See the discussion in Carroll's book around page 120.

However, it makes more sense to me not to assert that the energy is not conserved, but rather to assert that it is undefined. We simply cannot construct an integrated "energy" for the entire universe as a whole. For this, see the discussion in Robert M. Wald's book General Relativity, section 11.2 ("Energy") As Wald says, on page 286: "However, as already mentioned in chapter 4, there is no known meaningful notion of the energy density of the gravitational field in general relativity" The problem comes from an inability to separate the "dynamic" part of the field from its "background" part, where the energy would be associated with the dynamic part of the field.

But Sean Carroll tells us not to worry: "In the end, you should come to accept that there is a profound difference between flat and curved spacetimes, and some of our favorite notions from flat spacetime physics will be seriously modified in this more general context. This is not a sign of a flaw in general relativity, but a natural consequence of discarding the rigid spacetime geometry we learn to take for granted" (Sean Carroll, page 120).

It needs to be emphasized that, as Harrison implies, no "local" experiment is expected to violate conservation of energy, and this is in fact formally proven in general relativity. We are here talking only about the "energy" of the entire universe, defined as the integral of the energy density over all space.

Michael Mozina · Feb 28, 2009

DeiRenDopa said:
I think this is another Lather, Wash, Rinse, Repeat cycle ...

It wouldn't be like that if you could empirically demonstrate your claim in a real experiment with real control mechanisms. If you could demonstrate the existence of inflation and it's affect on nature we would not be in this position. Since I'm simply required to have "faith' in something that presumably does not exist anymore, and I don't happen to have faith in the idea, where exactly does that leave us?

The demonstrations were made in page 1 of this thread, and in the WMAP team paper I cited (among other places).

None of these uncontrolled observations were any sort of "demonstration" of concept. Let's look at a real "demonstration". Birkeland believed that electrical currents caused aurora. He didn't just write about the connection and work on paper, he *experimented with them in a lab*. In an empirical way, he demonstrated his idea with real spheres in a real plasma vacuum.

Compare and contrast that now with Guth. He started from a premise and postdicted a math fit and never once lifted a finger to physically demonstrate anything. You did not and could never provide an actual 'demonstration" of the effect on inflation on anything. You simply *asserted* it's temporary influence on the universe somewhere in the distant and murky past, and then postdicted a math fit to make it work. Noting was "demonstrated" empirically.

Of course, if one applies the MM criterion for acceptability, then it would seem that such "demonstrations" have not, in fact, been made ... at least for inflation (for DE it depends on what you mean; in at least two meanings, they have).

Inflation is the biggest leap of faith because evidently there is no hope of ever demonstrating it exists in nature because it does not exist in nature. The term DE seems to have a variety of meanings depending on whom you ask and how they personally view the idea.

In my next post, I'll bump a recent post of mine addressed to you that has not been answered yet; your answer may go some way to clarifying the extent to which your criteria are empirical, consistent, and useful.

I don't really get the impression you're actually looking for answers here. You only seem interested in finding some perceived inconsistency on my part instead of simply demonstrating that Lambda-CMD theory isn't "woo". It is certainly useless "woo". Inflation doesn't exist. It was a creative *imaginary* thing, but it isn't 'physically real', not today, and not ever. Nothing useful in a controlled experiment can be *predicted* based upon inflation, and it has plenty of know "anomalies" even in the only cosmology theory that actually needs or requires it. It's pure woo because it's a mathematical mythos like numerology, and like numerology it has zero predictive value in any controlled experiment.

PC/EU theory may in fact be "wrong', but it can't be "woo", because EM fields and gravity exist in nature and can be "demonstrated" to exists in nature. Inflation and DE are simply fudge factors for human ignorance and Lambda theory is 96% "hypothetical entity" and only 4% actual physics.

Michael Mozina · Feb 28, 2009

Tim Thompson said:
"The conservation-of-energy principle serves us well in all sciences except cosmology.

*Which* theory of cosmology?

In bound regions that do not expand with the universe (because they are dense compared with the average density of the universe), we can trace the cascade and interplay of energy in its multitudinous forms and claim that it is conserved.

Translation: These conservation processes work everywhere we can try it out. It's therefore a *law* of physics.

But in the universe as a whole it is not conserved.

That was a pure ad hoc assertion.

The total energy decreases in an expanding universe and increases in a contracting universe.

It requires *extra* energy to make it expand and especially to make it "accelerate". The total energy is the sum total of all energies at work. It can't be zero, especially in an acceleration scenario.

Where does energy go in an expanding universe?

The real question is "where did that extra energy to expand the universe come from"? What causes the expansion? Where did the energy of our physical universe come from?

And where does it come from in a contracting universe?

That would be gravitational potential energy that is converted into kinetic energy. There would necessarily need to be energy in the system before it even started to contract. The potential energy of the mass objects is simply there and it's not "going" anywhere except into kinetic energy as it contracts. There is no mystery here, but one must accept that the energy state is something greater than zero and it always has been greater than zero or we would simply not be here. The laws apply to all transactions in a positive energy universe.

The answer is nowhere, because in the cosmos, energy is not conserved."

Absolutely false. An ordinary pendulum can dispel this myth. In the "contraction" process all that happens is positive potential energy is converted into kinetic energy. As the kinetic energy reaches maximum, it is again turned back into potential energy. No energy is "lost". Likewise at the base of a stationary pendulum's cycle, it takes *external energy* to get the pendulum moving. Additional energy is necessary to explain expansion. This whole argument is bogus and easily debunked. All energy is conserved. In the contraction example we have positive potential energy converted to kinetic energy. In the expansion scenario we have positive kinetic energy being converted into potential energy. No energy conservations laws are being violated in any way.

This sounds exactly like an argument of the gaps. We know that the conservations laws apply *everywhere* except for *one cosmology theory*. I have no reason to believe these laws were *ever* violated under any condition. Do you have any evidence to the contrary from *controlled experimentation*?

This argument has absolutely zero credibility.

sol invictus · Feb 28, 2009

Tim Thompson said:
This looks correct to me, with the caveat that general relativity is rather far removed from my own areas of expertise. The problem is that general relativity conserves energy for all isolated or local systems, but does not conserve energy globally.

That's true only if you exclude the gravitational term from the energy. All those quotes you gave refer to the stress-energy tensor for matter, and exclude the energy-momentum pseudo-tensor piece (which is the GR analog of gravitational potential energy). There's a reason they do that - the gravitational term is a pseudo-tensor, not a real tensor, and does not really correspond to a local energy density except in the weak field limit - but nevertheless if you keep it, the energy in any closed region is strictly conserved (and zero).

IF you take a bounded region, the total of the bulk term plus the boundary term is always zero (but both can change as energy flows in and out). As I said earlier, that's a consequence of time reparametrization invariance. Many authors screwed up the boundary term, but its form is actually unique if you're careful enough. There's a lot of confusion over this issue (including in textbooks), but I can point you to some papers that do it right if you're interested.

The simplest case is a closed FRW universe (or any other solution that's spatially finite and without boundary). Then it's easy to show that the total energy is just 0 (and the physics of why is very clear - see below). In an infinite universe the integral over the whole volume isn't well defined, so one should pick a bounded region - and then energy can flow in and out. But it's still the case that the boundary term plus the bulk term is zero.

The whole thing is closely analogous to conservation of charge in EM. If you integrate the charge density over a volume - which is analogous to integrating the matter stress-energy - you get precisely minus a boundary term from the flux piercing the boundary (that's Gauss' law), which can also be expressed as an integral over the volume (using Stokes' theorem). And in a closed manifold, the total charge must be zero - because there is no boundary (the flux has nowhere to "go").

Michael Mozina · Feb 28, 2009

DeiRenDopa said:
Just so that I don't misunderstand ...

You seem to be saying that it is impossible, under any circumstances whatsoever, for something to be discovered 'in nature' from astronomical observations which later - maybe even decades or centuries later - becomes testable/verifiable/whatever in labs in controlled experiments; are you?

No.

To make this concrete: at least one element (helium) was first discovered in the spectrum of the Sun; later - ~a quarter of a century later - it was found in rocks here on Earth. By your criteria for assessing (astrophysics, in this case) scientific woo, helium did not exist until 1895, and all scientific work - by astronomers, chemists, geologists, etc - until then, on helium, should have received no MM-approved funding, as it would have been a clear-cut case of woo.

Did I get it right?

Not even close and that is a *terrible* example that only hurts your case. Whereas the wavelengths of various photons can be empirically traced to specific elements in controlled experimentation, inflation has no affect on anything. Inflation has no affect today, tomorrow or a million years from now so unlike the photon example you cited, no controlled experiment could even hope to identify the source of inflation. This only hurts your case, it certainly doesn't help it.

Michael Mozina · Feb 28, 2009

DeiRenDopa said:
Okey, dokey, ...

Follow-on question then: do I understand that you are completely and totally convinced that the only possible explanation/accounting of the various "DE" observations is "EM fields" or "electricity" or "electrical discharges" (or some such thing)? That it is utterly impossible for the "DE" observations to turn out to be some subtle combination of selection effects, stellar evolution, misapplication of GR, and downright bad luck (to make up one example)?

It could turn out to be *anything* that actually exists in nature. It can't be "dark energy' however because that does not exist in nature. If you're convinced however that there is an acceleration process in play in a mostly plasma universe, the obvious "likely candidate" would be an EM field. I don't really care what you stuff into a GR formula as long as you can demonstrate that what you stuff in there has real affect on real things.

Further, that, in the unlikely event that a full appreciation of the nature of DE, obtained by research such as that described in the paper, leads - directly or indirectly - to something really, really, really useful (a way to greatly improve the efficiency of fusion reactors perhaps), you will still declare the research to have been "the most pointless waste of money I can think of"?

In the "unlikely event" that you or anyone else ever actually "predicts" anything useful in a "controlled experiment" based on their faith in DE theory I'll happily recant my statement. Until then it looks and smells just like the same postdiction process that brought us nonexistent and utterly useless inflation.

Tim Thompson · Feb 28, 2009

Energy Redux

Tim Thompson said:
This looks correct to me, with the caveat that general relativity is rather far removed from my own areas of expertise. The problem is that general relativity conserves energy for all isolated or local systems, but does not conserve energy globally.

sol invictus said:
That's true only if you exclude the gravitational term from the energy. All those quotes you gave refer to the stress-energy tensor for matter, and exclude the energy-momentum pseudo-tensor piece (which is the GR analog of gravitational potential energy).

I have to say this looks wrong to me. For one thing, Wald is quite explicit, as is Carroll, that including gravity guarantees that the total energy of the universe will not be conserved, which is exactly the opposite of what you said. Indeed, quoting myself again ...

Tim Thompson said:
As Wald says, on page 286: "However, as already mentioned in chapter 4, there is no known meaningful notion of the energy density of the gravitational field in general relativity" The problem comes from an inability to separate the "dynamic" part of the field from its "background" part, where the energy would be associated with the dynamic part of the field.

This certainly looks like it includes gravity to me, and Wald explains exactly why.

sol invictus said:
There's a lot of confusion over this issue (including in textbooks), but I can point you to some papers that do it right if you're interested.

Count me in the interested group.

Tim Thompson said:
The answer is nowhere, because in the cosmos, energy is not conserved." Cosmology: The Science of the Universe; Edward Harrison, Cambridge University Press 2000, 2nd edition; page 349.

Michael Mozina said:
Absolutely false. An ordinary pendulum can dispel this myth.

You should try reading the posts that you respond to before you respond to them. That way you can look a bit more intelligent than you do at the moment ...

Tim Thompson said:
It needs to be emphasized that, as Harrison implies, no "local" experiment is expected to violate conservation of energy, and this is in fact formally proven in general relativity. We are here talking only about the "energy" of the entire universe, defined as the integral of the energy density over all space.

The pendulum is a "local" experiment and is therefore explicitly excluded from a discussion that refers only the the globally integrated energy of the entire universe.

The Man · Feb 28, 2009

Michael Mozina said:
*Which* theory of cosmology?

Translation: These conservation processes work everywhere we can try it out. It's therefore a *law* of physics.

That was a pure ad hoc assertion.

It requires *extra* energy to make it expand and especially to make it "accelerate". The total energy is the sum total of all energies at work. It can't be zero, especially in an acceleration scenario.

Well just what do you think conservation of energy means then? If the total energy of a closed system is conserved that means that the system as a whole does not gain or lose energy, so if some part of the system increases in energy (positive energy) then some other part must decrease in energy (negative energy). When you add up those changes + and – the total energy change of the system is zero.

Michael Mozina said:
The real question is "where did that extra energy to expand the universe come from"? What causes the expansion? Where did the energy of our physical universe come from?

That would be gravitational potential energy that is converted into kinetic energy. There would necessarily need to be energy in the system before it even started to contract. The potential energy of the mass objects is simply there and it's not "going" anywhere except into kinetic energy as it contracts. There is no mystery here, but one must accept that the energy state is something greater than zero and it always has been greater than zero or we would simply not be here. The laws apply to all transactions in a positive energy universe.

If the total energy of the universe is zero then there is no “extra” energy to ask about. However since you claim “The laws apply to all transactions in a positive energy universe” you’re going to have to ask yourself ‘Where did the energy of your positive energy universe come from?’.

Michael Mozina said:
Absolutely false. An ordinary pendulum can dispel this myth. In the "contraction" process all that happens is positive potential energy is converted into kinetic energy. As the kinetic energy reaches maximum, it is again turned back into potential energy. No energy is "lost". Likewise at the base of a stationary pendulum's cycle, it takes *external energy* to get the pendulum moving. Additional energy is necessary to explain expansion. This whole argument is bogus and easily debunked. All energy is conserved. In the contraction example we have positive potential energy converted to kinetic energy. In the expansion scenario we have positive kinetic energy being converted into potential energy. No energy conservations laws are being violated in any way.

This sounds exactly like an argument of the gaps. We know that the conservations laws apply *everywhere* except for *one cosmology theory*. I have no reason to believe these laws were *ever* violated under any condition. Do you have any evidence to the contrary from *controlled experimentation*?

This argument has absolutely zero credibility.

Actually you give it credibility as you note that one must add energy to separate gradationally attracting bodies thus two bodies closer together are in a lower energy state then when they are further apart. As a Bound State the interactive energy of gravity is negative thus requiring energy to separate the bodies.

Michael Mozina · Mar 1, 2009

The Man said:
Well just what do you think conservation of energy means then?

It means whatever energy exists in nature today has always existed. It may have changed 'forms', but energy cannot be created or destroyed. There has never been even a "zero" energy density in this universe, or prior to this universe.

If the total energy of a closed system is conserved

True.

that means that the system as a whole does not gain or lose energy,

True. Energy just changes form.

so if some part of the system increases in energy (positive energy)

Ok.

then some other part must decrease in energy (negative energy).

Woah. The first part is true, the "negative" statement is false. The energy state of something with a positive energy state can decrease alright, but it can only ever hope to reach a "zero" energy state. Even "empty space" (devoid of atoms and electrons) is still full of neutrinos and light and all sorts of energy. We cannot ever even reach a zero energy state, let alone a "negative" one. We can "decrease" the energy state, but never does it become "negative".

When you add up those changes + and – the total energy change of the system is zero.

No, it is just balanced at a positive energy state. In other words if the total energy state of the universe is nearly infinite today, it has always been so. The energy may have changed forms, but it has always existed. It cannot ever become a zero energy state because it has always been a positive energy state and energy is conserved.

If the total energy of the universe is zero then there is no “extra” energy to ask about.

If it was zero, the sun wouldn't shine, no mass or energy would exist today, and the sun would not warm my face in the morning.

However since you claim “The laws apply to all transactions in a positive energy universe” you’re going to have to ask yourself ‘Where did the energy of your positive energy universe come from?’.

Presumably that singularity thingy you have going at T=.000000000000000001 seconds. Alfven's model was more of a matter/antimatter universe that simply expanded and contracted by the way and no singularity was necessary or required. A positive energy state however is absolutely necessary and required.

Actually you give it credibility as you note that one must add energy to separate gradationally attracting bodies thus two bodies closer together are in a lower energy state then when they are further apart. As a Bound State the interactive energy of gravity is negative thus requiring energy to separate the bodies.

The only reason there is a gravitational attraction to begin with is because there is mass and energy in the system from the start. Imagine two hydrogen bombs sitting in space, sitting side by side, touching each other. Yes, it will take energy to move one away from the other. No, it is not true they have a zero energy state as we can demonstrate by blowing them up at the same time. Their internal positive energy will be transferred to photons, protons, electrons, neutrons, etc. There is no zero energy state. Matter is simply energy in a form that is "stable". It can be released into a different form of energy.

The bottom line here is that there was no "free lunch". Whatever energy makes up our current universe has always existed. It may have had an entirely different form (say a matter and antimatter "black hole"), but no energy was created or destroyed in the event we call the "bang", assuming it ever occurred. It would simply have been a transfer of energy from one form (whatever predated our universe) to another form (our universe). There has always been a positive energy state, and there has never been a negative energy state. That is what the conservation of energy laws insist.

Michael Mozina · Mar 1, 2009

Dancing David said:
Considering that you cherry pick evidence it is ahrd to talk to you. When you want to stop playing semantic, it would be easier.

I'm not "cherry picking" anything, and I'm not playing with semantics. I'm interested in empirical physics and it would be easier if you would too. The subjective "cherry picking" seems to be related to "interpretation" of "uncontrolled observations", which is the whole point and value in "empirical experimentation". No subjective leaps of faith are required in empirical physics.

You have yet to demonstrate a theory that explains the 'cosmological' redshift is something else.

Actually, I did.
http://arxiv.org/abs/astro-ph/0601171
Evidently "ordinary" expansion of objects would be fine. I don't know what the "cause" might have been, but the Klein-Alfven model was certainly "simpler" than your "explanation".

Until you do so, there is the redshift, there is the apparent acceleartion in the redshift. One theory is that dark energy drives teh acceleartion.

Even if that is all true, inflation and DE had nothing to do with it because they do not and never have existed in nature.

It is all about explaining data, all theories are just abstractions.

Some seem to be more "abstract" than others. Alfven's "bang" wasn't nearly as dependent on "fudge factors" to explain expansion.

I don't care, it is a theory that potentialy explains the data, whena better theory comes along then that theory will prevail.

Who subjectively decides what is a "better" theory, and how long might I have to wait around for it to eventually "prevail"? Birkeland died before any of his ideas were recognized as being true, and it could be another 60 years before they realize his explanation of solar wind was correct.

You are the one with the hang up.

Not me. I'm willing to explore lots of *empirical* ideas, whereas you seem to be fixated on one possible theory among an almost infinite number of possibilities to the exclusion of other options. You're "rating" them in ways that defy empirical or logical meaning.

yet you accept the existance of electrons and neutron, neither of which can be observed any more directly than the CMB or redshift.

I've already posted a link to an image of an electron reflecting laser light in a controlled experiment. Neutrons show up in a controlled experiment. Only inflation is shy around a lab.

You have a double standard. Your objection to the BBe is philosophical.

No, it's an "empirical" objection. Your argument itself is necessarily a philosophical argument because you lack empirical support for your idea. If that were not the case because you claimed "EM fields did it" for instance, this debate would be over instantly. It's only because you can't demonstrate inflation in an empirical way that this whole belief system boils down to an act of faith on the part of the "believer". Those of us that "lack belief" in inflation are forever deprived of any possibility of empirically demonstrating your claim, and therefore it is completely unattractive. It's also completely useless as well as it relates to anything currently happening in nature and therefore it is of no interest to someone like me for instance who is interested in solar activity.

I don't understand GR enough to derive the equations. But it does make sense.

Oddly enough I agree. Gr makes sense when it isn't being stuffed with non existent stuff. It's equations however can and have been abused from time to time.

If objects are drawn together by an arbitrary force, then that is some form of energy.

Sure. It's potential energy that can be converted to kinetic energy.

I sort of understand why they call it negative.

There is no such thing as "negative energy" however. Even antimatter is not negative energy because we can mix it with matter and release energy. The rest of your post seems to be a rehash, so I'll just stop here.

I can't wait to see how the positive ions have enough momentum to overcome the same force that draws the electrons towards the heliosphere.

You really should read Birkeland's work with spheres in a vacuum. He explains how material and oils from the sphere gets torn from the sphere and deposited onto the chamber walls. The electrons carry along positively charged ions in their wake.

Ziggurat · Mar 1, 2009

Michael Mozina said:
It means whatever energy exists in nature today has always existed. It may have changed 'forms', but energy cannot be created or destroyed.

OK. That's pretty much a standard physics statement.

There has never been even a "zero" energy density in this universe, or prior to this universe.

This is unsupported. In fact, in Newtonian physics, it's not even possible to define total energy in an absolute manner, because the definition of zero energy for potentials are always arbitrary. So the total energy of the universe can't even be defined in an absolute sense, all you can ever do is define changes in that total energy.

Woah. The first part is true, the "negative" statement is false. The energy state of something with a positive energy state can decrease alright, but it can only ever hope to reach a "zero" energy state.

Clue for the clueless: there are plenty of physical systems with no lower limit to the potential energy. In fact, anything with an attractive 1/r² force will produce a U = -1/r potential. You can try to make that potential positive by adding some constant (ie, U = C - 1/r), but since there's no lower limit to -1/r, the potential can always go negative no matter how big a constant you try to add. So you're completely wrong, and the proof was trivial.

We cannot ever even reach a zero energy state, let alone a "negative" one.

What's wrong with a negative energy state? In Newtonian physics, the only energies that ever even matter are local energy changes, which will be the same regardless of what the total global energy is, so why is it at all objectionable to have total energy equal to zero? It isn't.

If it was zero, the sun wouldn't shine, no mass or energy would exist today, and the sun would not warm my face in the morning.

This claim has no support. And it's simply wrong. The sun needs energy to shine, but it's irrelevant to that process whether or not that energy is balanced anywhere else by a negative potential energy. That balancing negative potential won't stop the sun from shining in any way, shape, or form.

sol invictus · Mar 1, 2009

Tim Thompson said:
I have to say this looks wrong to me. For one thing, Wald is quite explicit, as is Carroll, that including gravity guarantees that the total energy of the universe will not be conserved, which is exactly the opposite of what you said.

That's not at all what he's saying. He said "However, as already mentioned in chapter 4, there is no known meaningful notion of the energy density of the gravitational field in general relativity." What that means is that there is no local energy density. It does not mean there is no total energy.

Again, the problem arises because the would-be energy density for gravity is not a tensor - it doesn't transform homogeneously under coordinate transformations. However its integral - which can be expressed as a boundary term - is fine. When you integrate over a finite region which isn't the whole manifold, that energy isn't necessarily conserved simply because energy can flow in and out. But neither would electric charge be in such a region. Infinite expanding universes do pose a problem, because the integrals don't always converge when you take the region to be very large. But again, it's not much different than charge, and local conservation still works fine.

This certainly looks like it includes gravity to me, and Wald explains exactly why.

You've misunderstood him. The problem is with the existence of a local density, not a total.

Count me in the interested group.

Here's the original reference on this, but IIRC they restrict to asymptotically flat spaces.

R. Arnowitt, S. Deser, C. Misner: Coordinate Invariance and Energy Expressions in General Relativity, Phys. Rev. 122 (1961) 997–1006.

This one is more general:

S. W. Hawking, Gary T. Horowitz, The Gravitational Hamiltonian, Action, Entropy and Surface Terms

http://en.scientificcommons.org/95394

The technique in this second paper works fine for FRW cosmology (at least it does for de Sitter; I haven't investigated it in detail for others). It's really not complicated: you start with Einstein-Hilbert coupled to matter. That action has some terms with two derivatives of the metric. So you integrate it by parts to make it look more canonical, and then after you define the Hamiltonian in the usual way. But that integration by parts gives you some boundary terms, and the Hamiltonian constraint guarantees that the total (bulk plus boundary) is zero. So you take the boundary terms and call them the energy.

It's very much like Gauss' law, as I mentioned before.

Michael Mozina · Mar 1, 2009

Ziggurat said:
This is unsupported.

I beg to differ. It is supported by a "law" of physics. Energy cannot be created or destroyed and this universe contains lots of energy.

In fact, in Newtonian physics, it's not even possible to define total energy in an absolute manner, because the definition of zero energy for potentials are always arbitrary. So the total energy of the universe can't even be defined in an absolute sense, all you can ever do is define changes in that total energy.

Actually all we can do is define changes in the *layout* of energy over time. The total amount of energy has never changed. I may not be able to measure it all at the moment, but I know from laws of physics that the total energy has not changed one iota.

Clue for the clueless: there are plenty of physical systems with no lower limit to the potential energy. In fact, anything with an attractive 1/r² force will produce a U = -1/r potential. You can try to make that potential positive by adding some constant (ie, U = C - 1/r), but since there's no lower limit to -1/r, the potential can always go negative no matter how big a constant you try to add. So you're completely wrong, and the proof was trivial.

The negative sign you put in that formula is purely arbitrary and depends on the observer.

What's wrong with a negative energy state?

There isn't any such thing as "negative energy" in nature. Nature is full of energy and never even quite reaches a "zero" energy state. Even antimatter is not 'negative energy'. It's simply energy in a stable form that can be released from that form by mixing it with matter. There is no such thing as even a zero energy state in nature. Even a pure vacuum is going to be traversed by photons and neutrinos, so there can never be a "zero" energy state anywhere in this universe.

This claim has no support.

My warm face says otherwise.

And it's simply wrong. The sun needs energy to shine, but it's irrelevant to that process whether or not that energy is balanced anywhere else by a negative potential energy.

We already went through that "potential" energy thing with the pendulum. There is positive potential energy that is converted to *positive* kinetic energy and back again. That is all that happens. The pendulum doesn't hit a zero potential energy and then go negative by flying up and off planet Earth! Once it reaches zero, that's it. No negative energy is involved.

That balancing negative potential won't stop the sun from shining in any way, shape, or form.

Click to expand...

The fact you want to attempt to "balance" potential or kinetic energy against something else is purely arbitrary from the start. There simply is potential and/or kinetic energy in the system. None of it is "negative energy", all of it is "positive" energy in one form or another. The energy can and does change forms as in the pendulum example, but the movement of the pendulum (and the universe) demonstrates that there is energy in the system. There is no "balance" or even a change in the total energy (assuming a frictionless bearing) in the pendulum at any point in the process. It's simply positive energy going from one form of energy to another.

The initial energy state can be almost if not infinite, and the only thing that actually 'balances" are the actual energy exchanges. The total energy can be anything, all the matters is that total energy is preserved.

Click to expand...

Perpetual Student · Mar 1, 2009

Originally Posted by Perpetual Student
I am not familiar enough with the physics involved to comment on the concept of negative energy from the perspective of cosmology. However, in general, the concept of any quantity in nature being negative is one of convention from the perspective of the mathematics used. It all depends on where one puts zero. Negative points on the real line are just as valid as positive points. Similarly, any quantity that can be increased or decreased can have a negative value at some point, which will depend on where one assigns zero. It's that simple.
I can place an object on a table and decide to assign its gravitational potential energy at zero. If I raise it a few feet I can now decide it has a positive energy . If I lower it under the table it will now have a negative energy (in my coordinate system). I have no doubt that valid results can be obtained in doing physics using this convention. The fact that the energy is negative under the table has no mystical meaning; it's merely a way of doing the math.

MM response: Even if one arbitrarily sets things to zero, an accelerating physical universe full of mass and energy cannot have zero energy.

You have a fundamental problem! You make no attempt to learn from or even pay attention to any comments made here. Simply put, you are in combat and don't really make an effort to learn from or understand someone else's remarks. Your response above is nothing more than a quick knee jerk answer with no thought.
That's not science; it's dogma! You are not engaging in a scientific discussion; you are spouting blind MM dogma.
If you were to make any attempt to understand my comment above, you would realize that any system can be described as having zero energy. Then as the system evolves (in isolation) various aspects or parts of the system can have positive, zero or negative energy with the total system energy remaining at zero, which would be consistent with the conservation of energy law you know so well. That is true of the whole universe, which is a system (a big one).

Regarding cosmological questions about energy and the big bang, here is a view to consider: http://www.astrosociety.org/pubs/mercury/31_02/nothing.html
It may make you happier to call the total energy of the universe something like 10²⁷⁷ joules, but it would accomplish nothing. It would be a number that could not change, just like zero.

Michael Mozina · Mar 1, 2009

Perpetual Student said:
You have a fundamental problem! You make no attempt to learn from or even pay attention to any comments made here.

With all due respect PS, I have tried very hard to understand their position. I just don't happen to agree with it.

Simply put, you are in combat and don't really make an effort to learn from or understand someone else's remarks.

I'm sure it seems that way, but I am trying to understand their position and I've made an effort to pick on specific ideas and explain why they are not true.

Your response above is nothing more than a quick knee jerk answer with no thought.
That's not science; it's dogma! You are not engaging in a scientific discussion; you are spouting blind MM dogma.
If you were to make any attempt to understand my comment above, you would realize that any system can be described as having zero energy. Then as the system evolves (in isolation) various aspects or parts of the system can have positive, zero or negative energy with the total system energy remaining at zero, which would be consistent with the conservation of energy law you know so well. That is true of the whole universe, which is a system (a big one).

Regarding cosmological questions about energy and the big bang, here is a view to consider: http://www.astrosociety.org/pubs/mercury/31_02/nothing.html
It may make you happier to call the total energy of the universe something like 10²⁷⁷ joules, but it would accomplish nothing. It would be a number that could not change, just like zero.

Actually PS, I realize exactly what you meant, and I actually agree with you that we can *arbitrarily* pick an energy state as a zero state for purposes of experimentation.

The problem with their belief however is fundamentally a problem with the laws of nature. The energy state of this universe is not zero. The sun shining on Earth demonstrates this claim. The total energy state of this whole physical universe is not changing, but it cannot be zero. In fact the observation of acceleration makes it *impossible* for it to be zero.

I hope you spend as much time trying to understand my position as you would have me put into understanding your position on this issue. I think you will find that I am trying to be fair and reasonable, but the notion that the universe has no energy is obviously wrong. I can't ignore the fact that the sun shines and the world turns. There is energy in the universe now. It could not ever have been zero unless the laws of conservation of energy are not laws of physics.

Even the most remote reaches of space do not have even a "zero" energy state. While it can be handy in a math equations to think in terms of negative energy, in the realm of physics, that isn't what is going on. At the particle physical level (like neutrinos) the particles are moving and they convey positive kinetic energy into experiments here on Earth. We simply do not live in a "zero energy" universe. This one is full of energy.

Ziggurat · Mar 1, 2009

Michael Mozina said:
Energy cannot be created or destroyed

That formulation implies that it's a thing. But it is not. It's a property of things, which we can quantify. That quantity happens to be conserved, but that statement says nothing about its distribution or its total. Momentum is also conserved. The universe is full of momentum. And yet, the total momentum, as far as we can tell, is zero.

The total amount of energy has never changed. I may not be able to measure it all at the moment, but I know from laws of physics that the total energy has not changed one iota.

Nothing I said implies otherwise.

The negative sign you put in that formula is purely arbitrary and depends on the observer.

No, it is NOT arbitrary. It is necessary. Without that minus sign, energy would NOT be conserved. The constant C is arbitrary, but that minus sign is an absolute requirement. Again, you reveal yourself to be ignorant of freshman physics.

There isn't any such thing as "negative energy" in nature.

Except I already demonstrated that there must be for potential energies, or else you have potentials which are always infinite.

Even antimatter is not 'negative energy'.

Well, duh. Of course antimatter isn't negative energy. Nothing I said implies otherwise.

We already went through that "potential" energy thing with the pendulum.

You arbitrarily defined the potential energy as being positive. There was no requirement that it be positive. Everything works out the same if you define the top of the swing as zero, and the bottom as negative. You still get a loss of potential energy and an increase in kinetic energy. NOTHING about your scenario requires that we define the potential as positive anywhere. In fact, the only potentials which you have to define as positive are repulsive ones, for the same reason that attractive potentials can always go negative: repulsive potentials can be unbounded in the positive direction, while attractive potentials can be unbounded in the negative direction.

The pendulum doesn't hit a zero potential energy and then go negative by flying up and off planet Earth!

If its potential goes from positive to negative, that means it's getting closer to earth, not flying into space. Epic fail.

There simply is potential and/or kinetic energy in the system. None of it is "negative energy", all of it is "positive" energy in one form or another.

This is simply false. Whether or not potential energy is negative depends entirely upon where your zero reference is, which in Newtonian physics is arbitrary. But if the potential is unbounded at the lower end (which is the case for gravity), then you cannot define a zero such that it cannot go negative. But since you can't do math, and don't know why there's a negative sign in that potential, I guess it's not surprising that you don't understand why.

The total energy can be anything, all the matters is that total energy is preserved.

Bwahahahahaha! If the total energy can be anything, then it can be negative. Congratulations, you've just contradicted yourself.

DeiRenDopa · Mar 1, 2009

Ziggurat said:
[...]

Bwahahahahaha! If the total energy can be anything, then it can be negative. Congratulations, you've just contradicted yourself.

(bold added)

It seems that has happened rather a lot, in this and at least two other threads, that MM contradicts himself ...

It can happen to anyone, of course, but it would seem that it's a rather frequent event, for MM and his posts here.

It seems that sometimes MM tries to clarify the contradiction (or perhaps one should say 'apparent contradiction'), but IIRC it's very unusual for such attempts to actually resolve the apparent contradiction; rather, they make it worse, or more stark, or are in essence incoherent ("illucid", perhaps).

Does any reader, other than MM (presumably), feel this is an inaccurate summary, in any significant way?

temporalillusion · Mar 1, 2009

Michael Mozina said:
With all due respect PS, I have tried very hard to understand their position. I just don't happen to agree with it.

I don't think this is true. You've demonstrated almost no understanding of what they are trying to say. If you understood what they were saying then you wouldn't be making mistakes in rephrasing and interpreting what they are saying.

It's possible to understand someone else's position and disagree with it completely. You don't seem to understand the position being given here though.

You can tell this by the very common phrases "That's not what GR says" or "That's not what <insert whatever> says" being used.

Perpetual Student · Mar 1, 2009

Michael Mozina said:
The problem with their belief however is fundamentally a problem with the laws of nature. The energy state of this universe is not zero. The sun shining on Earth demonstrates this claim.

OK, stay with me on this one. The sun formed through the action of gravity on a cloud of dust and gas. Gravitational forces then facilitate nuclear reactions, which then release energy. But you know that the energy is being released by the sun -- not created. It is already there in the binding energy of the atoms involved in fusion. That energy and those atoms got there when those atoms were formed from the "positive" energy of the early universe. That "positive" energy used to create those atoms and binding energy were balanced by the "negative" gravitational energy caused by the expanding universe as stuff spread apart. That's not hard to understand, regardless of whether the total energy of the universe is some positive number of joules or zero. However, let the physicists here clean up my act on this one, if my explanation is lacking or flawed.

Michael Mozina · Mar 1, 2009

Perpetual Student said:
OK, stay with me on this one. The sun formed through the action of gravity on a cloud of dust and gas. Gravitational forces then facilitate nuclear reactions, which then release energy. But you know that the energy is being released by the sun -- not created. It is already there in the binding energy of the atoms involved in fusion. That energy and those atoms got there when those atoms were formed from the "positive" energy of the early universe.

So in this example gravity seems to facilitate the release of stored preexisting energy in atoms.

That "positive" energy used to create those atoms and binding energy were balanced by the "negative" gravitational energy caused by the expanding universe as stuff spread apart.

You've lost me here somehow. The gravitation energy in your example is actually helping to release energy that has been stored in atoms. It's more or less *adding* energy to the system to help facilitate fusion. As this release of energy occurs, the sun even loses a little "gravity" as protons and electrons accelerate toward the heliosphere. There is an "additive" property to gravity that is helping to create positive pressure, and to help heat the plasma to a temp that initiates fusion reactions.

I'm unclear hot gravity is being considered "negative' in this example.

I fully agree with your earlier statement that we can pick an arbitrary point to be a "zero" when experimenting with things like gravity, etc. There may be instances in such a math formula where such an equation can become negative in certain scenarios as well, as in your example. In this instance however we are interested in the total energy of the universe and there are physical processes for us to consider. Every moving object contains positive amounts of kinetic energy. Objects separated by distances have "positive potential energy" that can convert into positive kinetic energy. Particles that traverse space also have kinetic energy. The whole universe is essentially kinetic energy in motion. Even at the level of the atom, the electrons are not stationary and there is kinetic movement and kinetic energy and energy in general that can be released by fusion for instance in your example. There is an abundance of stored energy in this system, both in terms of kinetic energy of massive objects, and small objects, but also in terms of potential fusion and fission reactions that "release mass and gravity".

Essentially the energy state of the universe can be any *non negative* number, but it cannot be zero, nor can it be negative. Even antimatter is not "negative energy", it's essentially kinetic energy in another form that can be released from that form by the introduction of matter. Both types of matter contain energy that can be released in annihilation. No type of matter is a zero or negative kinetic energy state. All forms of matter have momentum and kinetic energy.

Michael Mozina · Mar 1, 2009

Ziggurat said:
That formulation implies that it's a thing. But it is not. It's a property of things, which we can quantify. That quantity happens to be conserved, but that statement says nothing about its distribution or its total. Momentum is also conserved. The universe is full of momentum. And yet, the total momentum, as far as we can tell, is zero.

This statement doesn't make sense to me. Why wouldn't the Earth then just fall into the sun?

No, it is NOT arbitrary. It is necessary. Without that minus sign, energy would NOT be conserved.

But the initial energy state is all that needs to be conserved. It can be any *positive* number.

The constant C is arbitrary, but that minus sign is an absolute requirement. Again, you reveal yourself to be ignorant of freshman physics.

I think it's outrageous to look at any of this in terms of "freshman physics" and then turn right around and claim there no energy in the universe. Come on. The posturing here is pointless.

Except I already demonstrated that there must be for potential energies, or else you have potentials which are always infinite.

The universe potentially contains an infinite (or nearly so) amount of energy for all I know. I can only see a small sliver of it, and that part has *lots* of energy that I experience with my eyes, my ears, etc.

Well, duh. Of course antimatter isn't negative energy. Nothing I said implies otherwise.

There is no form of energy that is "negative". The energy is kinetic in nature and movement oriented. You can take all movement out of the system and all energy out of the system and achieve a zero state, but in no way can you achieve a "negative energy" state. You might reach zero at best case.

You arbitrarily defined the potential energy as being positive.

No, I did not. It is "positive" kinetic energy that I can feel on my skin in the morning when I feel the sun hit my face. There is heat coming from the sun that is energy in motion.

There was no requirement that it be positive.

In physical motion scenarios, the energy is kinetic and it is positive.

Everything works out the same if you define the top of the swing as zero, and the bottom as negative. You still get a loss of potential energy and an increase in kinetic energy. NOTHING about your scenario requires that we define the potential as positive anywhere.

You're simply playing with an arbitrary starting point. It doesn't change the nature of the kinetic energy and the bottom of the swing. It will still have a "positive" affect on anything it might hit at that point in the swing. The energy is kinetic in nature, and there's always kinetic energy in the system. We're repeating now, so I'll skip a bit.

Bwahahahahaha! If the total energy can be anything, then it can be negative. Congratulations, you've just contradicted yourself.

And to think I'm being accused of not trying to understand your points and being combative. This is like lawyers looking for any slip of the tongue, not a person interested in understanding my point.

This universe is *filled* with kinetic energy in motion. You can't take it out of the system if you wanted to, and if you did you would only reach a state of zero kinetic energy. Since that cannot ever be achieved, we will forever be living in universe with a non zero amount of kinetic energy in motion and potential energy between objects. It is all "positive energy" because it is all kinetic in nature.

Michael Mozina · Mar 1, 2009

DeiRenDopa said:
(bold added)

It seems that has happened rather a lot, in this and at least two other threads, that MM contradicts himself ...

I'm sure if you want to twist my words you can, but if you want to understand the nature of kinetic energy it's easy to do. The energy state of the physical universe is not zero. The sunshine is proof of this statement. Gravity helped release the potential energy of atoms, it didn't cancel out that kinetic energy, it released that stored energy from the atom.

Michael Mozina · Mar 1, 2009

Ziggurat said:
This is simply false. Whether or not potential energy is negative depends entirely upon where your zero reference is, which in Newtonian physics is arbitrary. But if the potential is unbounded at the lower end (which is the case for gravity), then you cannot define a zero such that it cannot go negative. But since you can't do math, and don't know why there's a negative sign in that potential, I guess it's not surprising that you don't understand why.

You know, it's these statements that really tick me off. I understand the math just fine which I why I know your statements are false. It is you that do not seem to have a grasp of the actual physical processes that your mathematical equations relate to. You guys are *so* fixated *only* on the math side, that you utterly ignore the physics part entirely. The energy is *kinetic*. It can't be "negative' because all mass exists or it doesn't and it's moving (or not) and conveying positive kinetic energy (or not). It cannot be "negative" because it's simple kinetic energy. Even at the level of particle physics, neutrinos and photons convey kinetic energy. There is a positive amount of kinetic energy in the system that relates to the particles in motion that distribute this energy. There is no way the universe can have zero energy or we could not even have this conversation. You're lost in the math, and oblivious to the physics.

Michael Mozina · Mar 1, 2009

Perpetual Student said:
OK, stay with me on this one. The sun formed through the action of gravity on a cloud of dust and gas. Gravitational forces then facilitate nuclear reactions, which then release energy. But you know that the energy is being released by the sun -- not created. It is already there in the binding energy of the atoms involved in fusion. That energy and those atoms got there when those atoms were formed from the "positive" energy of the early universe. That "positive" energy used to create those atoms and binding energy were balanced by the "negative" gravitational energy caused by the expanding universe as stuff spread apart. That's not hard to understand, regardless of whether the total energy of the universe is some positive number of joules or zero. However, let the physicists here clean up my act on this one, if my explanation is lacking or flawed.

Let me try that two bomb analogy one more time. We could put them together and *call* it a "zero" energy state. We can add energy and move them apart a distance and add energy to the system. If we let them go, the potential energy is converted into kinetic energy. There is however energy inside the mass of the objects themselves that we can release at any time. That too is a form of 'energy' it is necessarily non negative, and non zero. We can then set them off and release that "stored energy" to verify that there was never really 'zero' energy in our system, we just chose that "zero" as a handy reference point. In reality however, even the mass has energy, and it is a "form of" energy that can be converted back into other forms of energy. Even though we can pick a zero arbitrarily, there are other physical factors at play and physical energy in matter itself.

The easiest and best way I can think to explain this is in terms of kinetic energy. Our universe is filled with kinetic energy which keeps the Earth from falling into the sun, and the sun from falling into the core of the galaxy. Even light and neutrinos all convey positive kinetic energy to other objects. The only thing that the conservations laws actually tell us is that whatever amount of total energy exists in the universe today it is not zero and it cannot be negative. It is simply kinetic energy and there is plenty of it in our universe.

temporalillusion · Mar 1, 2009

Michael Mozina said:
This statement doesn't make sense to me. Why wouldn't the Earth then just fall into the sun?

But that's exactly what it is doing. An orbit is falling is it not? Just falling around, not directly into. There's no energy constantly being expended to hold the earth up.

You say that you can see and feel energy so the energy of the universe can't be zero, you understand that they're saying the net energy is zero right?

Take entropy as an analogy.. entropy always increases, but it is allowed to decrease locally as long as it increases elsewhere right?

Same kind of thing, energy can be positive in some places, as long as its offset by negative energy elsewhere, so the sum total of all the energy in the observable universe is zero.

Michael Mozina · Mar 1, 2009

temporalillusion said:
But that's exactly what it is doing. An orbit is falling is it not? Just falling around, not directly into. There's no energy constantly being expended to hold the earth up.

There was kinetic energy put into the Earth to get it into this position to begin with. It has all the momentum it needs, but that momentum is *kinetic energy*.

You say that you can see and feel energy so the energy of the universe can't be zero, you understand that they're saying the net energy is zero right?

In this case it doesn't matter if you're talking net or gross energy. There is a net surplus of kinetic energy in this universe.

Same kind of thing, energy can be positive in some places, as long as its offset by negative energy elsewhere, so the sum total of all the energy in the observable universe is zero.

The energy in the universe is kinetic in nature. What is "negative energy"? Don't say "gravity" because gravity is not "negative energy". You can have *potential energy* thanks to gravity and distance, but that is simply another form of energy that can easily be converted back into kinetic energy.

That bomb analogy is the best example I can think of to demonstrate that a mass object does not have "zero" energy, even if it wasn't moving in relationship to anything else. The atoms in the device have energy and they can release that energy at at time. It is not that we have "zero" energy even with no kinetic energy due to movement of mass objects. Even the mass is itself composed *of energy*.

temporalillusion · Mar 1, 2009

Michael Mozina said:
There was kinetic energy put into the Earth to get it into this position to begin with. It has all the momentum it needs, but that momentum is *kinetic energy*.

Sure but the kinetic energy isn't what is holding it up there, it's falling. If it wasn't moving it would fall in without any help. It takes "negative energy" to bring the earth and the sun together (as opposed to positive energy to bring two like charges together).

Michael Mozina said:
In this case it doesn't matter if you're talking net or gross energy. There is a net surplus of kinetic energy in this universe.

Based on what? Where did the energy come from? They've supported the net zero energy with GR, you'll have to support surplus kinetic energy with something as comprehensive and well supported.

Michael Mozina said:
The energy in the universe is kinetic in nature. What is "negative energy"? Don't say "gravity" because gravity is not "negative energy". You can have *potential energy* thanks to gravity and distance, but that is simply another form of energy that can easily be converted back into kinetic energy.

Semantics? Does it matter if you call it potential energy or call flat space zero and a gravity well negative energy? The result is the same, if you want to pull something out of a well you have to give it positive energy.

Michael Mozina said:
That bomb analogy is the best example I can think of to demonstrate that a mass object does not have "zero" energy, even if it wasn't moving in relationship to anything else.

Who claimed that a mass object has zero energy? No one.

Skwinty · Mar 1, 2009

Zero Energy Universe

Sorry to drag up "Null Physics", but wasn't one of the tenets of null physics the fact that the universe sums to zero.

derekmcd · Mar 1, 2009

Hi again Michael,

Not sure if you challenged me on Ari B's paper. Honestly, I don't wish to dig through this thread to find it.

I would like to present you with a simple, laboratory experiment that describes negative energy.

Let's use a rubberband. Place this rubberband between your two fingers and stretch it. How much you stretch it is irrelevant. The work you applied to stretching this rubberband is kinetic energy. Now, when you are holding this rubberband, it also has potential energy. The potential energy is the stored energy that wants to snap the rubberband back to its original shape.

I believe we all agree that the kinetic energy applied to the rubberband to make it stretch can be considered 'positive' energy. We applied a force to the rubberband. We have added energy to a closed system.

It would seem that your conundrum is defining the potential energy. I think it is simple, basic physics. Let go of the rubberband and let it return to its natural shape. Should we also consider that a positive energy? I think not. If both the kinetic energy and potential energy are positive, then we have some serious issues. We are creating free, unlimited energy. If I stretch and release my rubberband, I am creating energy for free.

The laws of conservation demand that one of the two energy sources be considered negative. If you can explain it a different way, I'd love to hear it.

Skwinty · Mar 1, 2009

Violation of Conservation of Energy in an expanding space

Baryshev in "Expanding Space: The root of conceptual problems of the cosmological Physics" link posted earlier.

"The problem of the absence of a true EMT for gravity field in cosmology appears as the violation of energy conservation"

Ziggurat · Mar 1, 2009

Michael Mozina said:
This statement doesn't make sense to me. Why wouldn't the Earth then just fall into the sun?

Dear oh dear. You don't know? Well, first, angular momentum and linear momentum aren't the same thing (you can have one be zero while the other is not), and second, globally vanishing momentum doesn't mean locally vanishing momentum, of either kind.

But the initial energy state is all that needs to be conserved. It can be any *positive* number.

Your insistence that it must be positive is without any basis. There is nothing wrong with negative potential energies.

I think it's outrageous to look at any of this in terms of "freshman physics"

When you master freshman physics, we can move on to more advanced topics. But right now, that's the level at which your comprehension is failing. Potential energies can be negative. This is indeed a point which gets drilled into freshmen.

You can take all movement out of the system and all energy out of the system and achieve a zero state, but in no way can you achieve a "negative energy" state. You might reach zero at best case.

The gravitational potential energy of two point masses interacting with each other is lowest when their separation is zero. Now, if we assign that as our zero potential energy state, what's the potential energy for any nonzero separation? Why, it's infinite, for ALL nonzero r. Do the path integral if you don't believe me. The ONLY way around that is to assign some nonzero r as our zero potential. In which case, there will always be r's where the potential is negative.

No, I did not. It is "positive" kinetic energy that I can feel on my skin in the morning when I feel the sun hit my face. There is heat coming from the sun that is energy in motion.

All that tells you is about the sign of the change in energy. It tells you nothing about its absolute value. How could it? In Newtonian physics, its absolute value has no meaning.

In physical motion scenarios, the energy is kinetic and it is positive.

Potential energy is not kinetic energy. You had problems comprehending this with magnetic fields too, even though in that case the potential energy was positive.

You're simply playing with an arbitrary starting point.

No ****, Sherlock. That's rather the whole point: where you set your zero in Newtonian physics is completely arbitrary.

It doesn't change the nature of the kinetic energy and the bottom of the swing.

I never said it did.

It will still have a "positive" affect on anything it might hit at that point in the swing.

If I go from U=5 J and KE=0 to U=3 J and KE=2 J, you're OK. But for some reason, you can't wrap your head around the idea of going from U=0 and K=0 to U=-2 J and KE=2 J. Still gots me some positive kinetic energy there.

The energy is kinetic in nature, and there's always kinetic energy in the system.

No. At the top of the swing, there is no kinetic energy. Kinetic energy and potential energy are not the same thing. Are you really that confused about physics that you can't recognize the difference?

Michael Mozina said:
You know, it's these statements that really tick me off. I understand the math just fine

Then prove it. F=-dU/dt. If F=-1/r² (an attractive potential), what is U?

The energy is *kinetic*.

We've been through this before. You are wrong. I've even given you examples of cases with magnetic fields where I gave you reasons (physical reasons) why the energy cannot be kinetic.

Dancing David · Mar 1, 2009

Michael Mozina said:
This statement doesn't make sense to me. Why wouldn't the Earth then just fall into the sun?

.

But we can't have evolved from monkeys, there are still monkeys!

Dancing David · Mar 1, 2009

Michael Mozina said:
In this case it doesn't matter if you're talking net or gross energy. There is a net surplus of kinetic energy in this universe.

Uh, sure , this contradicts something, what is it that you have been talking about, what was it, ... it will come to me in a moment...

conservation of something?

Oh I know, consistency of application!

Wear your belt in the cherry picker, you might fall out.

sol invictus · Mar 1, 2009

Michael Mozina said:
I think it's outrageous to look at any of this in terms of "freshman physics"

You're absolutely right, and Zig was wrong. This isn't freshman physics..... it's primary school physics. And you fail utterly.

Aren't you ashamed? You've got a website devoted to the sun. You even have papers about it (published, even - I shudder for the peer review system). And yet you don't know that gravitational potential energy is negative.

30 seconds of googling results in this,, this, and this.

Obvious common sense and basic physics - just let two objects fall towards ech other - indicates the same, and has been explained to you over and over.

High school calculus - integrate gravitational force over a distance, or find the potential whose gradient is the field - gives the same.

Not to understand this basic fact, with your background.... I honestly don't know how to interpret that, other than as a sign of plain old stupidity. But I have faith in people, generally - try to actually think about this, and maybe you'll be able to learn something.

Lambda-CDM theory - Woo or not?

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