Unraveling the Mystery of Total Energy in the Universe

[Curious6]

Is it really zero, as suggested by some scientists, or it is slightly more or less? Any papers published on this topic?

 

[Nenad]

the third law of Thermodynamics says that the total energy of the universe is constant, and no, it is not 0. If it was 0, you wouldent be alive today, matter would not exist.

 

[Chronos]

It depends on how you define energy. A number of theorists, Hawking among them, have suggested the 'zero energy' concept. It is attractive because it avoids the problem of a universe that sprang from nothing to something. The universe consists of positive energy (matter) and negative energy (gravity) whose total is exactly zero! This is a valid mathematical solution for the Hamiltonian density of the universe in GR. The issue is, however, complex and different answers are possible depending on the geometry of space time.

for a brief discussion: http://www.astrosociety.org/pubs/mercury/31_02/nothing.html

It is, however, easier to forget about positive and negative energy and fall back on thermodynamics saying, as Nenad did, that the total energy of the universe is constant and unchanging [although it could still be zero].

 

[Yogesh Dayal]

A zero point energy is exactly at a center point between two extremities of the infinity i.e. -∞ to +∞ and both these extremeties of the universe are always present.
Breaking the zero equally or symmetrically on to both sides, consumes energy that you may call energy taken by the system, where as collapsing these both symmetrical sides back to zero will return the energy back. Now in one case it is positive energy while in another case it will be negative. Think yourself as to which will be positive and which one negatuve ??

 

[Yogesh Dayal]

I mean it to be negative ...

 

[Blueplanetbob]

Simply put then, doesn't it just mean that that all the changing energies in the universe are in balance, giving a stable universe?

 

[Chronos]

Simply put then, doesn't it just mean that that all the changing energies in the universe are in balance, giving a stable universe?

Correct, Bob. That conclusion is consistent with GR predictions.

 

[marcus]

.

for a brief discussion: http://www.astrosociety.org/pubs/mercury/31_02/nothing.html

.

Chronos this is a very good link. If you did not put it on the A&C Sticky thread (for handy references) already then I will

I have heard Alex Filippenko lecture---he is outstanding, with good slides clear explanations humor and verve----the co-author Jay Pasachoff is
a very successful textbook writer in general astro, with many books.

I was worried that we didnt seem to come to grips with this zero energy puzzle in Curious other thread (Closed Flat or Open?) where Curious asked it as a follow up question.

but now the question has been addressed.

BTW it is still not completely clear to me how the U does this. but it is gradually getting more clear

(I remember hearing Alex say this free lunch thing around 1990-1992
but still have difficulty picturing it)

 

[nenorse]

I'm not a scientist - but this subject interests me. It seems to me that if the universe is infinite, then the total energy must be zero as

e=mc²

thererfore to work out the energy we can say

mc²
____________ = 0
infinity

As anything over infinity tends to 0 - what's my flaw here?

 

[joemo13]

I'm not a scientist - but this subject interests me. It seems to me that if the universe is infinite, then the total energy must be zero as

e=mc²

thererfore to work out the energy we can say

mc²
____________ = 0
infinity

As anything over infinity tends to 0 - what's my flaw here?

This only gives you the average distribution of the energy over the volume of the Universe, but not the total energy in the Universe, as mc[SUP2[/SUP] is equal to e, so therefore you have calculated the total energy divided by the "infinite" volume of the Universe, not the total energy itself

 

[TalonD]

Chronos this is a very good link. If you did not put it on the A&C Sticky thread (for handy references) already then I will

I have heard Alex Filippenko lecture---he is outstanding, with good slides clear explanations humor and verve----the co-author Jay Pasachoff is
a very successful textbook writer in general astro, with many books.

I was worried that we didnt seem to come to grips with this zero energy puzzle in Curious other thread (Closed Flat or Open?) where Curious asked it as a follow up question.

but now the question has been addressed.

BTW it is still not completely clear to me how the U does this. but it is gradually getting more clear

(I remember hearing Alex say this free lunch thing around 1990-1992
but still have difficulty picturing it)

here is a quote from the link above:

Perhaps many quantum fluctuations occurred before the birth of our universe. Most of them quickly disappeared. But one lived sufficiently long and had the right conditions for inflation to have been initiated. Thereafter, the original tiny volume inflated by an enormous factor, and our macroscopic universe was born. The original particle-antiparticle pair (or pairs) may have subsequently annihilated each other – but even if they didn’t, the violation of energy conservation would be minuscule, not large enough to be measurable.

I think there is a problem with this idea. If there were quantum fluctuations before the birth of our universe then in what spacetime did they occur? In order for one or many quantum fluctuations as the article suggests, to occur, doesn't there have to be a pre-existing spacetime volume in which it occurs? This seems to imply that a single qf in a preexisting spacetime was a center point from which our universe expanded but I think we all agree that our universe doesn't have a center. This is confusing. It seems to be some kind of circular argument, like which came first the chicken or the egg.

Marcus, your'e smart enough.. set me strait on this.

boy, I just realized how old this thread is... :P

 

[pixel01]

Is it really zero, as suggested by some scientists, or it is slightly more or less? Any papers published on this topic?

If we accept the equation E = mc^2 then E is not zero.

 

[James S Saint]

I can't believe you guys are seriously arguing about this stuff. The very definition of "energy" voids the possibility of "zero energy" (Hawkings is a media clown). In fact, you can't even have negative energy. What would negative energy be? - "The ability to undo work?" Which would BE work, of course.

http://metapointperspective.blogspot.com/2010/05/how-god-creates.html" - don't worry about the use of the word "God". It gets explained in the post.

 

[nicksauce]

he very definition of "energy" voids the possibility of "zero energy" (Hawkings is a media clown). In fact, you can't even have negative energy.

http://hyperphysics.phy-astr.gsu.edu/hbase/gpot.html#ui

Notice the negative sign for gravitational potential energy...

 

[James S Saint]

http://hyperphysics.phy-astr.gsu.edu/hbase/gpot.html#ui

Notice the negative sign for gravitational potential energy...

Haha.. surely, you aren't serious?

He is talking about the reduction of energy after coming closer to the planet from outer space. The available energy within a system can be reduced. That yields equations with negative signs because they represent a reduction from a prior state of the system. It doesn't mean the existence of negative energy.

The concept of negative energy is like the concept of a negative circle or negative light. You can have negative directions and sizes, but not negative existences.

 

[Nabeshin]

Casamir effect?

 

[James S Saint]

Casamir effect?

Was that rhetorical?

 

[WhoWee]

I can't believe you guys are seriously arguing about this stuff. The very definition of "energy" voids the possibility of "zero energy" (Hawkings is a media clown). In fact, you can't even have negative energy. What would negative energy be? - "The ability to undo work?" Which would BE work, of course.

What is your credibility to make such a statement?

 

[James S Saint]

What is your credibility to make such a statement?

Credibility is subjective to you. Logic is the issue. Negative energy, required to obtain a "zero energy", is the same concept as "negative existence". Something either exists or it doesn't. There is no "negative" to existence other than an existence having reverse properties nominally declared "negative". But the reverse properties of energy, the ability to do work or make change, would not be merely the inability to do work or make change, but the ability to un-work and un-change. But un-working is working and un-changing is change, merely in a different direction at best and thus it is the same abstract concept. There is no "un-working" concept. You either cause change or you do not. There is no negative concept to change.

 

[Antiphon]

Jimmy, you would love physics if you got to know it a bit better.

Negative energy particles are falling into black holes by the trillions that's the only way to pull mass out of them. And yes it uncauses the original matter to unexist an undo itself. Even a "clown" who hold's Newton's chair knows that.

 

[James S Saint]

Jimmy, you would love physics if you got to know it a bit better.

Negative energy particles are falling into black holes by the trillions that's the only way to pull mass out of them. And yes it uncauses the original matter to unexist an undo itself. Even a "clown" who hold's Newton's chair knows that.

And Phony, you would probably love logic if you got to know it a bit better.

If reputation could undo logic, the Pope would be the Father of Science too, undoing all of that effort to use reason to discover truth. Negative energy only falls into the hole in your ability to reason.

 

[danyalson]

I'm kinda new to this but I attempted to calculate the total positive energy in the universe based on approximations of the total mass in the universe. Because the best approximations of total universal mass vary, the total I calculated is a range based on several approximations. I do not yet fully understand zero-sum, however I will take the day to try to understand it better. BUT, here is what I have calculated to be the total positive energy in the universe. Please feel free to correct anything I have said or any calculations I have produced.
Based on the approximations that the total mass of the Universe is between 10⁵³ and 10⁶⁰ I have calculated the total energy to be:

E=8.9875517873681764x10¹³⁵(10^±7)

 

[Brown Arrow]

umm first off energy in the universe is finite as in there is a number to it, second the energy is not zero, if zero universe would not exist!

 

[travwg33]

If you have an hour watch this. Lawrence Krauss, a theoretical physicist, describes how there TE = 0

 

[Chronos]

The net energy of the universe can be zero, without requiring a zero energy universe at all scales. That is like the homegenous universe. It can be homogenous on large scales, but, decidedy inhomogenous locally - like the solar system.

 

[Brett13]

So I am only in high school and all of you are a lot smarter then I, But when we do total energy changes in chemistry..we sometimes end up with a negative energy value... maybe its a different type deal, but the law of conservation of energy states that energy is neither created nor destroyed, so how could there be "negative" energy. Maybe I shouldn't even be replying to this thread...haha... . ..

 

[magellanic3]

So I am only in high school and all of you are a lot smarter then I, But when we do total energy changes in chemistry..we sometimes end up with a negative energy value... maybe its a different type deal, but the law of conservation of energy states that energy is neither created nor destroyed, so how could there be "negative" energy. Maybe I shouldn't even be replying to this thread...haha... . ..

I think u are talking about exothermic and endothermic reaction.guess only.

 

[Chronos]

Er, show me the math. You missed the point. Imaginary charges are routinely considered in electronic circuits.

 

[dejesusluisx]

How can gravity have a negative energy value, when gravity still hasn't been defined? The last time I checked there was one side supporting general relativity claim that gravity was a bend in space time and another side supporting it was a particle called gravitons.

Can someone clarify this? I'm not a physicist I'm a biologist, but I love the subject.

Thanks