[pluto]

G’day from the land of ozzzzz

Its a nice day in Sydney, clear sky and cool nice temp.

I read this paper sometime ago, very interesting, just sharing the reading.

Simulations of Ultrarelativistic Magnetodynamic Jets from Gamma-ray Burst Engines
http://aps.arxiv.org/abs/0803.3807

Authors: Alexander Tchekhovskoy (1), Jonathan C. McKinney (2), Ramesh Narayan (1) ((1) Harvard CfA/ITC, (2) Stanford University/KIPAC)
(Submitted on 27 Mar 2008 (v1), last revised 8 May 2008 (this version, v2))

Abstract: Long-duration gamma-ray bursts (GRBs) require an engine capable of driving a jet of plasma to ultrarelativistic bulk Lorentz factors of up to several hundred and into narrow opening angles of a few degrees. We use global axisymmetric stationary solutions of magnetically-dominated (force-free) ultrarelativistic jets to test whether the popular magnetic-driving paradigm can generate the required Lorentz factors and opening angles. Our global solutions are obtained via time-dependent relativistic ideal magnetodynamical numerical simulations which follow the jet from the central engine to beyond six orders of magnitude in radius. Our model is primarily motivated by the collapsar model, in which a jet is produced by a spinning black hole or neutron star and then propagates through a massive stellar envelope. We find that the size of the presupernova progenitor star and the radial profile of pressure inside the star determine the terminal Lorentz factor and opening angle of the jet. At the radius where the jet breaks out of the star, our well-motivated fiducial model generates a Lorentz factor $gammasim 400$ and a half-opening angle $theta_jsim 2^circ$, consistent with observations of many long-duration GRBs. Other models with slightly different parameters give $gamma$ in the range 100 to 5000 and $theta_j$ from $0.1^circ$ to $10^circ$, thus reproducing the range of properties inferred for GRB jets. A potentially observable feature of some of our solutions is that the maximum Poynting flux in the jet is found at $theta sim theta_j$ with the jet power concentrated in a hollow cone, while the maximum in the Lorentz factor occurs at an angle $theta$ substantially smaller than $theta_j$ also in a hollow cone. [abridged]

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G’day

What do you mean by making light?

[pluto]

G’day from the land of ozzzzzzzz

I remember in 1965 discussing the same topic on solar sails.

Its funny how this topic has not blown away.

[pluto]

G’day from the land of ozzzzzzzzz

In recent years the research of jet formation and it properties has greatly improved.

One opinion and not the only.
Dark matter located in the core and dark energy in the jet stream.

At the end of the day its all about matter and its phases.

So it does MATTER what we say.

[pluto]

G’day from the land of ozzzz

I read out of darkness.

So far he talks around the topic.

I’m interested to read if he has anything to say.

[pluto]

G’day from the land of ozzzzzzz

Sail is the slow way to china.

Magnetic reconnection and the strorage of an ultra dense plasma matter in a magnetic confinement would be the ultimate power to go where no man has gone before, deep space far far away.

[pluto]

G’day from the land of ozzzz

Magnetic reconnection

Magnetic Reconnection 2009
http://arxiv.org/find/all/1/all:+AND+2009+AND+Magnetic+reconnection/0/1/0/all/0/1

The topic becomes more interesting the more you read.

That link show 2009

Alter the year and it will give you that year.

[pluto]

G’day from the land of ozzzzzzzz

Magnetic reconnection in plasma jets get close to the speed of light.

Could this be so for space ships?

[pluto]

G’day from the land of ozzzzzzzz

This is an interesting link

Plasma Astrophysics Problems in Star and Planet Formation
Feb-09

http://adsabs.harvard.edu/abs/2009arXiv0902.3617Z
http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009arXiv0902.3617Z&link_type=PREPRINT&db_key=PRE

The major questions relevant to star and planet formation are: What controls the rate, efficiency, spatial clustering, multiplicity, and initial mass function of star formation, now and in the past? What are the major feedback mechanisms through which star formation affects its environment? What controls the formation and orbital parameters of planets, especially terrestrial planets? These questions cannot be fully addressed without understanding key magnetohydrodynamics (MHD) and plasma physics processes. Although some of these basic problems have long been considered intractable, attacking them through a combination of laboratory experiment, theory, and numerical simulation is now feasible, and would be fruitful. Achieving a better understanding of these processes is critical to interpreting observations, and will form an important component of astrophysical models. These models in turn will serve as inputs to other areas of astrophysics, e.g. cosmology and galaxy formation.

[pluto]

G’day Zeus

Main stream or alternative cosmology should not have an influence over science evidence.

Magnetic reconnection is probably the key to triggering the formation of the jets.

http://arxiv.org/abs/0903.3968
Reconnection Electric Field and Hardness of X-Ray Emission of Solar Flares

Authors: Chang Liu, Haimin Wang
(Submitted on 23 Mar 2009)

Abstract: Magnetic reconnection is believed to be the prime mechanism to trigger solar flares and accelerate electrons up to energies of MeV. In the classical two-dimensional reconnection model, the separation motion of chromospheric ribbons manifests the successive reconnection that takes place higher up in the corona. Meanwhile, downward traveling energetic electrons bombard the dense chromosphere and create hard X-ray (HXR) emissions, which provide a valuable diagnostic of electron acceleration. Analyses of ribbon dynamics and HXR spectrum have been carried out separately. In this Letter, we report a study of the comparison of reconnection electric field measured from ribbon motion and hardness (spectral index) of X-ray emission derived from X-ray spectrum. Our survey of the maximum average reconnection electric field and the minimum overall spectral index for 13 two-ribbon flares show that they are strongly anti-correlated. The former is also strongly correlated with flare magnitude measured using the peak flux of soft X-ray emissions. These provide strong support for electron acceleration models based on the electric field generated at reconnecting current sheet during flares.

[pluto]

G’day from the land of ozzzzzzzz

This link may help you a bit.

Alternative Cosmology Group Newsletter – 2007 Year End Review
http://www.cosmology.info/newsletter/2007_year_end.htm

E Lerner hit the nail on the head.

The BBT reminds me of the “King does not wear invisible robes“.

[pluto]

G’day from the land of ozzz

Hello Zeuz

The BBT is a mistake by scientists affter cash flow for projects. No BB project no money.

In the last 10 years there has been a flow of information and hundreds of scientists who have not accepted the BBT.

Its dead in the water.

Regardless, one needs to look at the science evidence and not ad hoc ideas when making up models.

and above all to understand that the king does not wear invisible robes.

[pluto]

G’day from the land of ozzzzzzzz

Hello newbie

What part do you want to discuss?

[pluto]

G’day from the land of ozzzzzzz

Some issues can be explained via particle theory others by wave theory.

It does no matter which theory is applied at the end of the day MATTER chooses its form.

[pluto]

G’day

The axis of evil
http://lanl.arxiv.org/abs/astro-ph/0502237

Local Pancake Defeats Axis of Evil
http://lanl.arxiv.org/abs/astro-ph/0509039

Is Cosmic Parity Violation Responsible for the Anomalies in the WMAP Data?
http://lanl.arxiv.org/abs/hep-th/0601034

CMB multipole measurements in the presence of foregrounds
http://lanl.arxiv.org/abs/astro-ph/0603369

http://lanl.arxiv.org/abs/astro-ph/0604410
Occam’s razor meets WMAP
Authors: Joao Magueijo, Rafael D. Sorkin
(Submitted on 19 Apr 2006)

Abstract: Using a variety of quantitative implementations of Occam’s razor we examine the low quadrupole, the “axis of evil” effect and other detections recently made appealing to the excellent WMAP data. We find that some razors {it fully} demolish the much lauded claims for departures from scale-invariance. They all reduce to pathetic levels the evidence for a low quadrupole (or any other low $ell$ cut-off), both in the first and third year WMAP releases. The “axis of evil” effect is the only anomaly examined here that survives the humiliations of Occam’s razor, and even then in the category of “strong” rather than “decisive” evidence. Statistical considerations aside, differences between the various renditions of the datasets remain worrying.

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Recycling Universe

These links that I’m reading through, does not mean that I agree with. At this moment in time, not many people know what is going on out there. There are varies theories, with some people very emotional over their theory. If you wish to read up on these types of links just let me know.

[0806.1245] Ekpyrotic and Cyclic Cosmology
Ekpyrotic and Cyclic Cosmology

[0806.1080] Phantom Energy Accretion onto Black Holes in Cyclic Universe
Phantom Energy Accretion onto Black Holes in Cyclic Universe

[0806.1065] B2FH, the Cosmic Microwave Background and Cosmoloy
B2FH, the Cosmic Microwave Background and Cosmoloy

[0806.0746] The model of dynamo with small number of modes and magnetic activity of T Tauri stars
The model of dynamo with small number of modes and magnetic activity of T Tauri stars

[0805.0413] Oscillating universe with quintom matter
Oscillating universe with quintom matter

[0803.4484] Recollapsing quantum cosmologies and the question of entropy
Recollapsing quantum cosmologies and the question of entropy

[0803.4446] Anti-deSitter universe dynamics in LQC
Anti-deSitter universe dynamics in LQC

[0802.1875] Cyclic Magnetic Universe
Cyclic Magnetic Universe

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