New visualization techniques yield star formation insights
December 31, 2008
This image shows a very long-exposure view of a 1-degree- square area within the Perseus star-forming region. The colors correspond approximately to "true" color, and the regions which appear very dark show the obscuration caused by concentrations of interstellar dust associated with the star-forming cores discussed in the Letter in Nature. The image gives an impression of the generally "turbulent" (swirling) nature of interstellar material in star-forming regions. This is a "flat" image of the sky, in that it does not contain any information about depth. The "3D" images published in Nature show views of this region taken with radiotelescopes where the line-of-sight velocity of gas is used to separate regions at different distances, which appear super-imposed on each other in this more traditional flat optical image. Image courtesy Jaime Pineda & Jonathan Foster
New computer visualization technology developed by the Harvard Initiative in Innovative Computing has helped astrophysicists understand that gravity plays a larger role than previously thought in deep space's vast, star-forming molecular clouds.
The insight, to be reported in the Jan. 1 issue of the journal Nature, is being illustrated in the journal's online version through new three-dimensional Portable Document Format (PDF) technology that will allow readers to view the article's key graphics using free PDF software already commonly found on computers.
The work was led by Astronomy Professor Alyssa Goodman of Harvard's Faculty of Arts and Sciences, the Harvard-Smithsonian Center for Astrophysics, and the Initiative in Innovative Computing (IIC), of which she was the founding director. Goodman and colleagues used the IIC technology to examine reams of astronomical data collected on a structure known as a giant molecular cloud.
Previous technology, Goodman said, doesn't allow for careful consideration of what she described as "hierarchical" structure — essentially regions within regions — and would have obscured specific details in the molecular cloud, such as nested areas of varying density and a physical break from one area to another.
"There's no way of noticing this without being able to see this in 3-D," Goodman said.
Michael Halle, senior scientist at the IIC and instructor in radiology at Harvard Medical School and Brigham and Women's Hospital, said this research shows that visualization technology is a critical part of the analysis and discovery process and not just a way to display data once it has been gathered, analyzed, and understood.
"You're learning about your data through visualization and interaction," said Halle. "You can take all the data, selectively filter it, and look at it in a different way."
Halle praised the IIC as an important forum within which researchers with different fields of expertise can work together.
"Without the IIC's collaborative infrastructure, multidisciplinary resources, and other support, this research would not have happened," Halle said.
The research team also included Erik Rosolowsky of the University of British Columbia, Michelle Borkin of the IIC and Harvard's School of Engineering and Applied Sciences, Jonathan Foster and Jaime Pineda from the Harvard-Smithsonian Center for Astrophysics, and Jens Kauffmann of the IIC and the Harvard-Smithsonian Center for Astrophysics.
The team took advantage of tools developed by the IIC's ongoing Astronomical Medicine (A-M) project, managed by Halle, which uses technology devised for medical imaging on astronomical research. To visualize the molecular cloud in three dimensions, it used Astronomical Medicine's 3-D Slicer program, originally devised to analyze medical images.
The key advance, however, is a new computer algorithm — a set of instructions on how to handle data similar to a computer program or model. The algorithm, developed by Rosolowsky, outputs results in a "dendrogram," which is a treelike representation of data. From the dendrogram, researchers were able to create 3-D displays of the data that they could then rotate and examine from many different directions.
The data, which are part of the ongoing COMPLETE (COordinated Molecular Probe Line Extinction Thermal Emission) Survey of Star Forming Regions, measure emission from a type of carbon monoxide molecule in the cloud. The carbon monoxide serves as a proxy for the vast amounts of hydrogen that make up most of the cloud and from which stars form. In deep space's bitter cold, hydrogen gives off very little emission so a proxy such as carbon monoxide is needed.
Computer simulations are critical tools in understanding the behavior of these clouds and of star formation, Goodman said. The simulations are the only way that astronomers can watch what happens over the millions of years it takes to form a star. Past models of star formation in these clouds assumed that since gravity is a weak force over large distances, its effects are negligible in these clouds until the hydrogen atoms are very close together. These popular models, Kauffmann said, assume that most of the changes in the clouds come from turbulence and that it is only after turbulence pushes molecules close enough that gravity comes into play.
Once denser groupings of molecules are formed and gravity becomes a factor, they attract more and more particles until either something disrupts them or they have enough mass to collapse and form a star.
But it is the process up to the point where the dense groupings form that Goodman and colleagues examined. Their analysis shows that, rather than turbulence being the only significant force pushing these gas molecules around, their gravitational influence on each other is also significant. That finding means that existing models, which leave gravity out until very dense clumps have formed, would over-predict the rate of star formation in these clouds.
The research will be presented in a novel way for Nature, Goodman said. It will be the first time a major scientific journal has used a 3-D PDF of graphics in an article. The 3-D PDF format has been used before, primarily in manufacturing and advertising. The Adobe Acrobat PDF software, including the free Adobe Reader, is common on many computers.
The conversion of the 3-D images into PDF format from the more technical 3-D Slicer software used by the IIC was done using software produced by a New Zealand company, Right Hemisphere, which has been working to make 3-D publishing a mainstream technology and a way to communicate complex data, according to founder Mark Thomas.
"We see the use of 3-D in publishing by Harvard and Nature magazine to be a significant milestone in publishing history and are very proud to have been able to assist and guide the process," Thomas said.
Source: Harvard-Smithsonian Center for Astrophysics
Jan 05, 2009 |
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http://iic.harvar...tive.pdf
Happy new year to everyone!
============.
Now it is considered, that Cold model of the Universe
certainly does not correspond to a reality.
I have another point of view.
========..
We supposed that graviton particles:
a)
Theoretically predicted but never observed ( a hypothetical
particle ) with no electric charge and no mass is supposed
to be responsible for the gravitational interaction between
matter and energy.
b)
A hypothetical elementary particle is responsible
for the effects of gravity (the quantum of gravitation ).
It means, that the initial gravitational mass of stars
and planets is created from gravitation particles .
Nobody knows :
%u201CWhat geometrical and physical parameters
can gravitation particle have ?%u201D
The Einstein%u2019s GRT doesn%u2019t explain
which particles create a gravitation field.
I will try to explain it.
======.
1.
Where has the first material gravitation particle appeared from ?
Now it is considered, that reference frame which
is connected with relict isotropic radiation
T = 2,7K is absolute.
But T = 2,7K is not a constant factor.
This relict isotropic radiation continues to increase and
its temperature will decrease.
And, hence, approximately over a period of
20 billions years it will reach T=0K.
Therefore the gravitation particle can appears from
Nothing, from Vacuum, from Absolute Zero: T=0K.
1.
Let us take some area of Vacuum (T=0K)
and mark it with letter R.
The number of particles in this area of Vacuum
we will mark with letter N.
Then every particle of this area has
gravity/ mass of rest: R/N= k.
2.
Can they have volume?"
No.
Because according to J. Charles law ( 1787),
when the temperature falls down on 1 degree
the volume decreases on 1/273. And when the
temperature reaches -273 degree the volume
disappears. The physicists say, if the particle
has completely lost its volume
the physical parameters of particles become infinite.
But such statement contradicts the
"Law of conservation and transformation energy".
And then we must understand that the sense of the
"Law of conservation and transformation energy" is.
We should understand and accept that
when volume of the particles disappears
they become "indefinitely flat figures ".
What do "indefinitely flat figures " mean?
They mean, that we cannot reach Absolute Vacuum T=0K
and we also cannot reach density of the particle in the T=0K.
The %u201C Charles law%u201D was confirmed by other physicists:
Gay-Lussac ( 1802), W. Nernst ( 1910), A. Einstein ( 1925) .
These " flat figures " have the geometrical form
of a circle, as from all flat figures the circle has the most
optimal form: C/D= pi = 3,14.
These R/N= k particles are initial gravitational particles.
============.
Which is common condition of gravitation?
Let us suppose that in some local sphere of Vacuum
the quantity of the passive particles ( k) that is equal to
the number Avogadro N was found.
Then according to the principle of Boltzmann,
the gathering of the particles in some local sphere of Vacuum
has a probable basis: S= klnW.
It is common condition of gravitation.
================.
How did from these gravitation particles (k )
the first material particles appear ?
1.
The first material particles was called %u201Chelium%u201D, because
helium exist very %u2013 very near absolute zero: T=0K.
Nobody knows what helium is.( !)
Why?
Because the behavior of helium is absolutely different
from all another elements of Nature. ( !)
!!!!
I will try to explain, how the helium
was created from R/N=k.
2.
The helium exists very near absolute zero: T=0K.
Therefore we must take in attention the processes
of superfluids and superconductors , which require extremely
low temperatures , approximately 0K.
3.
Then , the first particles which were created
from R/N =k could be helium II ( He II ),
which created temperature 2,7K.
4.
Then , the second particles which were created
from helium II ( He II ), could be helium I ( He I ),
which created temperature 4,2K.
/ Kapitza / Landau theory./
5.
And then all the system comes to rotary movement.
But helium rotates differently from all other liquids.
If one rotates helium very strongly, it starts to behave not as liquid
but as elastic body (experience of E.L. Andronikashvili. /Georgia./ ).
Separate layers of helium become elastic ropes that change
the picture of quiet uniform rotation completely.
In such rotation sharp friction between different
layers of the liquid originates. From rotary elastic ropes
the slices of substance of various size come off.
Further they break to particles that received
the names of Helium-three 3He and Helium-four 4He.
The common thermal temperature in liquid increases .
#
Rotation and collision of the particles 3He and 4He at some
stage leads to their further crush to small particles, that received
the name of the nucleus of hydrogen atom- proton (p).
Protons are initial, the smallest, material particles.
#
The most widespread elements in stars are helium and hydrogen.
Our Sun consists of helium to 30% and of hydrogen to 69%.
Ii was found that in external layers of our Sun on 1kg of hydrogen
it was necessary 270g of helium. In deeper layers on 1kg of hydrogen
it is necessary 590g of helium.
Thus it is deeper into Sun it is more helium.
And in the central area of Sun helium-II, helium-I are found.
The reaction between (k ) , helium and
hydrogen go basically on the Sun.
All the elements of the material substance
are created from the initial particles (k) and helium.
==============. . .
How does all the system come to rotary movement ?
1.
If gravitation-particles fly to different sides,
they can not create the initial gravitational mass of planets, stars.
It means, that any unknown power collects the gravitation
particles together and gives to them the movement in one direction.
As a result of this common movement of all gravitation
particles (k ) in one direction the initial gravitational mass
of planets and stars is created.
What power can gather all particles together?
2.
Classic physics asserts, that in a Vacuum T=0K the motion
of particles stops, and the energy of Vacuum is equal to zero.
The quantum physics asserts, that in a Vacuum T=0K there is
motion of particles, and the energy of Vacuum is not zero.
Therefore, let us take some energy area of Vacuum and
mark it with letter E.
The mass of this energy area of Vacuum we will
mark with letter M.
Then every particle of this area has energy/mass of rest:
E/M= c^2, ( E=Mc^2, M=Ec^2.)
3.
As this particle is in the state of rest condition
it impulse is equal to zero ( h=0).
4.
But this particle can change its state of rest condition.
If the particle has impulse of Goudsmit -Uhlenbeck h= h/2pi,
its energy will be: E=hw
The thermal balance of Vacuum will be disturbed.
The actively rotating particle with energy E=hw gibes the
movement of surrounding passive particles R/N=k and
a gravitational field begins to create.
And the source of a gravitational field is an active Electron E=hw.
The remaining particles R/N=k are passive participants
(victims) of the creating gravitation field.
============. . .
Once again.
The stars are formed by the scheme:
e- -->k --He II-- He I --rotating He--thermonuclear reaction %u2013 %u0440%u2026
1.
hv = kT logW.
hv > kT logW.
hv < kT logW.
2.
hv --> He II --> He I -->
( P. Kapitza , L. Landau , E.L. Andronikashvili theories).
(Superconductivity, superfluidity theories.)
3.
Plasma reaction... --> Thermonuclear reactions ...-->.......
4.
Proton.
#
The Second law of thermodynamics doesn%u2019t forbid this process.
======================.
Best wishes.
Israel Sadovnik. / Socratus.
http://www.socratus.com
http://www.wbabin.net
http://www.wbabin.net/comments/sadovnik.htm
=======...
1.
Henry Poincare named the conception of "entropy "
as a " surprising abstract ".
2.
Lev Landau (Dau) wrote:
" A question about the physical basis of the
entropy monotonous increasing law remains open ".
3.
The mathematician John von Neumann said to
"the father of information theory" Claude Shannon:
" Name it "entropy" then in discussions
you will receive solid advantage, because
nobody knows, what "entropy" basically is ".
=============..
1.
Between 1850 - 1865 Rudolf Clausius published a paper
in which he called " The energy conservation law" as
" The first law of thermodynamics". But in our nature the
heat always flows from the higher temperature to the
lower one and never back. In our everyday life we don't see
the heat itself rises from cold to hot. So, it seemed that
in thermodynamics " The energy conservation law"
wasn%u2019t kept, this law was broken. But Clausius had another
opinion. He thought: I know people believe that this process is
irreversible, but I am sure that " The energy conservation law"
is universal law and it must be correct also for thermodynamic
process. So, how can I save this law ?
Probably, in the thermodynamic process there is something
that we don't know. Maybe, there is some degradation
of the total energy in the system which never disappears .
Perhaps, there is some non-useful heat, some unseen process ,
some unknown dark energy , some another form of potential
energy/heat itself which can transform heat from the cold
body to the warm one. I will call this conception as " entropy"
and it will mean that changes of entropy (dS) can be calculated
for reversible process and may be defined as the ratio of the
quantity of energy taken up (dQ) to the thermodynamic
temperature (T), i.e. dS= dQ /T.
And because I don't know how this process goes I won't call
it as a law but as " The second principle of thermodynamics "
which says that " the entropy of an isolated system always
increases ". Another version: " No process is possible
in which the only result is the transfer of heat from a hotter
to a colder body. It is possible some reversible process which
is unknown now ."
2.
Between 1870 - 1880 Ludwig Boltzmann said:
" Clausius is right. But I can add more to his entropy conception.
First.
According to Classic physics when an isolated thermodynamic
system comes to a thermal equilibrium all particles stop their
moving. From one hand it is correct. But the system cannot be
at thermal equilibrium (in the state of thermo death) all the time.
The situation in the system must change.
Therefore I say that at the thermal equilibrium the entropy
(some unknown dark/potential energy ) of the system will
reach maximum and as a result , the thermal equilibrium
of the system will change.
Second.
I don't know how exactly the thermal equilibrium of the system
changes. But I can give probabilistic / statistical interpretation
of this changing process. I can write " The second principle of
thermodynamics" by a formula: S= k log W and this formula
says:" the entropy ( heat) of the system is the collective result of
mechanical motion and friction of all the particles (k)."
I will call it as " The second law of Thermodynamics."
3
In 1900 Max Planck said:
Clausius and Boltzmann are both right.
But all my life I worked almost exclusively on problems
related to thermodynamics. And I am sure that the " The second
law of Thermodynamics" , concerning entropy, is deeper and it
says more than is generally accepted. I am sure the Boltzmann's
probabilistic /statistical version of "The second law of
Thermodynamics " is not completed, is not final.
Please, look at the graph of the radiation curves of the " black body".
They are very similar to those curves which are calculated
by Maxwell for the velocity (i.e. energy) distribution of gas
molecules in a closed container. Could this black body radiation
problem be studied in the same way as Maxwell's ideal gas....
...electromagnetic waves ? This problem of connection between
radiation of black body and Maxwell's Electrodynamics theory
doesn't give me peace. Maxwell's theory can tell everything
about the emission, absorption and propagation of the radiation,
but nothing about the energy distribution at thermal
equilibrium. What to do? How to be ?
After trying every possible approach using traditional
classical applications of the laws of thermodynamics
I was desperated. And I was forced to consider that the
relation between entropy, Boltzmann's probability version
and Maxwell's theory is possible to solve by suggestion ,
that energy is radiated and absorbed with discrete
individual quanta particle (E= hv). So, now I must write
" The second law of Thermodynamics " by formula:
hv = k log W.
But if I look to the Clausius inequality I see that entropy
is energy divided per temperature.
So the formula hv = klogW is hv = kT logW I think.
I was so surprised and sceptical of such interpretation the
entropy that I spent years trying to explain this result
in another , less revolutionary way. It was difficult for me
to accept this formula and to understand it essence .
It was hard for me to believe in my own discovery.
==================..
My conclusion.
How to understand this formula?
Which process does formula (hv = kT logW ) describe ?
1.
In 1877 Boltzmann suggested that the energy/mass state
of a physical system (of ideal gas ) could be discreted.
This idea was written with formula: R/N=k. It means:
there are particles with energy/mass state (k) in physical
system of ideal gas . They dont move, they are in the
state of rest.
2.
In 1900 Planck followed Boltzmann's method of dividing.
Planck suggested that energy was radiated and absorbed
with discrete "energy elements" - " quantum of energy"-
- " Planck's action constant"- (h) . This fact means:
electron produces heat, setting in mechanical motion and
friction all particles. This fact is described with Planck's
formula: hv = kTlogW.
3.
In which reference frame does this process take place?
In thermodynamical reference frame of ideal gas and
black body (M. Laue called this model as Kirchhoff,s vacuum).
Now it is considered that these models are abstract ones which
do not exist in nature. On my opinion these models explain
the situation in the real Vacuum (T=0K) very well.
4.
For my opinion the formula (hv = kT logW ) says:
a)
The reason of " entropy" , the source of thermal equilibrium's
fluctuation , the source of Vacuum fluctuation is an action of
the particle /electron, which has energy: E = hv (hf).
b)
The process of Vacuum fluctuation depends on collective
motions of all particles (k) and will be successful if enough
statistical quantity of Boltzmann's particles ( kT logW)
surround the electron.
c)
Which process does the formula (hv = kT logW ) say about ?
This formula describes the possibility of realization of
macro state from micro state. This formula explains
the beginning conditions of gravitation,
the beginning conditions of star formation.
1.
hv = kT logW.
hv > kT logW.
hv < kT.
2.
hv --> He II --> He I -->
( P. Kapitza , L. Landau , E.L. Andronikashvili theories).
(Superconductivity, superfluidity.)
3.
Plasma reaction... -->
4.
Thermonuclear reactions ...-->......etc.
d)
Thanks to Entropy the homogeneous Vacuum is broken.
Thanks to Entropy the micro process changes into
macro process.
Thanks to Entropy the stars formation takes place.
Thanks to Entropy " the ultraviolet catastrophe" is absent.
Thanks to Entropy our Milky Way doesn't change into radiation.
Thanks to Entropy the process of creating elements takes place.
Thanks to Entropy the process of evolution is going.
e)
One physicist said :" The entropy is only a shadow of energy%u201C.
Maybe now somebody can understand why entropy is a shadow.
And maybe now somebody will understand why
" The Law of conservation and transformation of energy"
is also correct for thermodynamic system.
f)
Why is " The second law of Thermodynamics"
so universal? Because it is based on
" The Law of conservation and transformation of energy"
And this law is not the simple accounting solution of debit and credit.
The sense of this law is dipper and it says more than is usually accepted.
===========..
#
The law that entropy always increases -- the second law of
thermodynamics -- holds I think, the supreme position among the laws
of Nature. If someone points out to you that your pet theory of the
universe is in disagreement with Maxwell's equations - then so much
worse for Maxwell equations. If it is found to be contradicted by
observation - well these experimentalists do bungle things sometimes.
But if your theory is found to be against the second law of
Thermodynamics, I can give you no hope; there is nothing for it but to
collapse in deepest humiliation.
/ Sir Arthur Stanley Eddington /
#
Dark energy may be vacuum
http://www.eureka...1607.php
#
Sakharov's induced gravity: a modern perspective
Authors: Matt Visser (Washington University in Saint Louis)
(Submitted on 19 Apr 2002)
Abstract: Sakharov's 1967 notion of ``induced gravity'' is currently
enjoying a significant resurgence. The basic idea, originally presented
in a very brief 3-page paper with a total of 4 formulas, is that gravit
is not ``fundamental'' in the sense of particle physics. Instead it was
argued that gravity (general relativity) emerges from quantum field
theory in roughly the same sense that hydrodynamics or continuum
elasticity theory emerges from molecular physics. In this article I will
translate the key ideas into modern language, and explain the various
versions of Sakharov's idea currently on the market.
http://arxiv.org/.../0204062
#
When the next revolution rocks physics,
chances are it will be about nothing%u2014the vacuum, that endless
infinite void.
http://discoverma...erything
http://discoverma...cs/space
#
==============..
Best wishes.
Israel Sadovnik. / Socratus.