Sunday, March 25, 2007

T Minus 3 Days - Conference Opening

No promises, but I will attempt to blog about every day of Outstanding Questions for the Standard Cosmological Model, to describe some of the other speakers.

Monday morning has been scheduled with safe stuff. Roger Blandford will talk about "Origins and Tests of the Standard Model." In his position, he is often forced to repeat the party line. Gary Hinshaw will talk about WMAP results. Ofer Lahav, Lloyd Knox and Bob Nichol will mostly talk about "dark energy."

Subir Sarkar's talk at 12:15 should be interesting. This Oxford physicist is one of the few brave enough to question the existence of DE. His talk will ask "Does WMAP require dark energy?" Roger Penrose of Oxford has implied that WMAP results were analysed fro the perspective of a currently fashinable model.

After lunch Tom Shanks of Durham University will speak on "Problems with the Current Cosmological Paradigm." That is a lot to pack into a 30-minute talk. The hypothesised amount of "dark energy" is extremely close to the amount of other stuff. Quantum field theory says that if DE exists it should be 10^120 times bigger.

The Concorde cosmology puts us in the middle of hypothetical forces--a repulsive "inflaton" causing initial expansion, another repulsive energy causing current acceleration, and our Ptolemaic world in the middle. Cosmologists call this the Nancy Kerrigan problem: Why me? Why now? Given the unwanted attention last week, I can identify with Nancy.

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5 Comments:

Anonymous a quantum diaries survivor said...

Hi Louise,

in my blog some discussion of the Riofrio affair has been going on in the comments section of a post (off to London). I just wanted to let you know, since you might want to answer some of the comments there.

Cheers,
T.

6:55 AM  
Blogger nige said...

I just looked up the blog post mentioned in the previous comment and the comments are shut down, preventing any response.

Tony Smith kindly quoted a little bit I wrote saying something like "the total gravitational potential energy of the universe is on the order E = MMG/R = MMG/(ct), which when equated to E=Mc^2 gives Louise's equation"

However, this was then dismissed by another comment from somebody else, who did not go back and check my comment on the other blog. The point is, I also have a lot more justification, such as the reason why you need to equate the gravitational energy with the rest mass energy.

Consider a star. If you had a star of uniform density and radius R, and it collapsed, the energy release from gravitational potential energy being turned into explosive (kinetic and radiation) energy is E = (3/5)(M^2)G/R. The 3/5 factor from the integration which produces this result is not applicable to the universe where the density rises with apparent distance because of spacetime (you are looking to earlier, more compressed and dense, epochs of the big bang when you look to larger distances). It's more sensible to just remember that the gravitational potential energy of mass m located at distance R from mass M is simply E = mMG/R so for gravitational potential energy of the universe is similar, if R is defined as the effective distance the majority of the mass would be moving if the universe collapsed.

This idea of gravitational potential energy shouldn't bee controversial: in supernovae explosions much energy comes from such an implosion, which turns gravitational potential energy into explosive energy!

Generally, to overcome gravitational collapse, you need to have an explosive outward force.

The universe was only able to expand in the first place because the explosive outward force, provided by kinetic and radiation energy, which counteracted the gravitational force.

Initially, the entire energy of the radiation was present as various forms of radiation. Hence, to prevent the early universe from being contracted into a singularity by gravity, we have the condition that E = Mc^2 = (M^2)G/R = (M^2)G/(ct) which gives GM = tc^3.

****************

My earlier comment:

Two ways to get GM = tc^3:

(1)

Consider why the big bang was able to happen, instead of the mass being locked by gravity into a black hole singularity and unable to expand!

This question is traditionally answered (Prof. Susskind used this in an interview about his book) by the fact the universe simply had enough outward explosive or expansive force to counter the gravitational pull which would otherwise produce a black hole.

In order to make this explanation work, the outward acting explosive energy of the big bang, E = Mc^2, had to either be equal to, or exceed, the energy of the inward acting gravitational force which was resisting expansion.

This energy is the gravitational potential energy E = MMG/R = (M^2)G/(ct).

Hence the explosive energy of the big bang's nuclear reactions, fusion, etc., E = Mc^2 had to be equal or greater than E = (M^2)G/(ct):

Mc^2 ~ (M^2)G/(ct)

Hence

MG ~ tc^3.

That's the first way, and perhaps the easiest to understand.


(2)

Simply equate the rest mass energy of m with its gravitational potential energy mMG/R with respect to large mass of universe M located at an average distance of R = ct from m.

Hence E = mc^2 = mMG/(ct)

Cancelling and collecting terms,

GM = tc^3

So Louise’s formula is derivable.

The rationale for equating rest mass energy to gravitational potential energy in the derivation is Einstein's principle of equivalence between inertial and gravitational mass in general relativity (GR), when combined with special relativity (SR)equivalence of mass and energy!

(1) GR equivalence principle: inertial mass = gravitational mass.

(2) SR equivalence principle: mass has an energy equivalent.

(3) Combining (1) and (2):

inertial mass-energy = gravitational mass-energy

(4) The inertial mass-energy is E=mc^2 which is the energy you get from complete annihilation of matter into energy.

The gravitational mass-energy is is gravitational potential energy a body has within the universe. Hence the gravitational mass-energy is the gravitational potential energy which would be released if the universe were to collapse. This is E = mMG/R with respect to large mass of universe M located at an average distance of R = ct from m.

****************

What's interesting is that the mainstream doesn't want to discuss science when it comes to alternatives, as Tony Smith makes clear in his discussion of censorship.

They use ad hominem attacks, which is a lazy approach whereby no careful science or disciplined checks are involved. The mainstream however objects if ad hominem attacks are used against it's leaders. For example, Dr Ed Witten - M-theory creator - was misleading when he claimed:

‘String theory has the remarkable property of predicting gravity.’ - Dr Edward Witten, M-theory originator, Physics Today, April 1996.

Dr Peter Woit remarks that the prediction is just a prediction of an unobservable spin-2 graviton and not a prediction of anything to do with gravity that is either already experimentally verified or checkable in the future:

‘There is not even a serious proposal for what the dynamics of the fundamental ‘M-theory’ is supposed to be or any reason at all to believe that its dynamics would produce a vacuum state with the desired properties. The sole argument generally given to justify this picture of the world is that perturbative string theories have a massless spin two mode and thus could provide an explanation of gravity, if one ever managed to find an underlying theory for which perturbative string theory is the perturbative expansion.’ – Quantum Field Theory and Representation Theory: A Sketch (2002), http://arxiv.org/abs/hep-th/0206135

If you call mainstream M-theory hypers ‘liars’, ‘charlatans’, ‘crackpots’, etc., you find that you are then accused of being a ‘science hater’. So they don't like criticism.

To give credit where due, Dr Ed Witten published a letter in Nature, Nature, Vol 444, 16 November 2006, stating:

‘The critics feel passionately that they are right, and that their viewpoints have been unfairly neglected by the establishment. ... They bring into the public arena technical claims that few can properly evaluate. ... Responding to this kind of criticism can be very difficult. It is hard to answer unfair charges of élitism without sounding élitist to non-experts. A direct response may just add fuel to controversies.’

So Dr Ed Witten at least doesn't encourage attacks on critics, he just prefers to ignore them. Maybe this is worse for critics with alternative ideas, however, where the choice is controversy or being ignored altogether.

But the mainstream as a whole does go far out of its way to use ad hominem attacks on alternatives, hence Lubos Motl's attacks, and many others.

1:53 PM  
Blogger nige said...

One new idea which occurs to me: the two types of derivation in the above comment could be combined to prove one or the other. If you can take the first type of derivation as experimentally sound, for example, then that would allow you to theoretically derive Einstein's equivalence principle between inertial and gravitational mass.

2:04 PM  
Blogger Kea said...

Yes, Nigel. In fact CarlB has made good progress on this derivation for the SM particle case. Higher order structures require the operad tower of quantisations.

2:48 PM  
Blogger QUASAR9 said...

lol Louise,
You are not getting paranoid are you. You should have just said you are a 'model' coming to a fashion shoot in London, they would have waved you thru. What passport are you travelling on.

Anyway I've phoned up Gatwick immigration and told them you are the famous Riofrio and that I'll vouch for you. LIC is only a couple of hours away by train, so you should arrive in time.
Have a nice day!

(hugs) - Q

PS I've got to attend a meeting today, but I'm sure our paths will cross soon

9:04 PM  

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