Archive for the ‘Astrophysics’ Category

Will Starburst Galaxies Explode the Big Bang?

June 11, 2018

There are MUCH MORE GIANT STARS THAN EXPECTED IN THE UNIVERSE (Factor of ten?)

I have proposed that the Big Bang Model is wrong, and that the universe could be much older, of the order of 100 billion years old, not 13.8 billion years; my iconoclastic and inconsiderate reasoning was philosophical: we have one expansion mechanism, DARK ENERGY. That expansion, Dark Energy, was directly observed, it exists, it’s not a figment of imagination. Many a physicist made a sour face, as Dark Energy was not expected at all: hundreds of arrogant  claims to explain the whole universe, talk to the media and the gullible as if one were god, and then, next thing one knows, one’s theories don’t explain 95% of the universe…

So an insolent philosophy asked: ‘Why would we need another cosmic expansion mechanism?’ Especially one expansion mechanism NOT directly observed, a figment of the imagination, the so-called Inflaton Field, necessary to make the Big Bang theory work (because of arcane complications: basically the universe as observed is around 100 billion light years across, and can have got that big only if it expanded at 10^10 times the speed of light, or something like this… Confusing enough? I have explained what is going on here and there, such as the locality of the speed of light, and the embedding theorem of Lorentzian manifolds. Stay tuned…)

A (Non Spectacular) Starburst galaxy, the Cigar, 12 million light year away. Full starburst galaxies are very blue, from the giant extremely hot (thus blue) stars in their midst. How much do we know about Helium formation in such super giant stars? Philosophers want to know!

So why is the Big Bang necessary? Besides making some people more puffed up than god itself?

Inspired by the H bombs they were thoroughly familiar with, Gamow, Alpher and Herman proposed the hot Big Bang as a means to produce all of the elements: extreme heat caused collisions and the nuclei fused (from the “STRONG FORCE”).

The lightest elements (hydrogen, helium, deuterium, lithium) were produced in the Big Bang nucleosynthesis

Ms. Burbidge, Mr. Burbidge, Fowler and Hoyle worked out the nucleosynthesis processes that go on in stars, where the much greater density and longer time scales allow the triple-alpha process (He+He+He –>> C) to proceed and make the elements heavier than helium.

But BBFH could not produce enough helium. The solution, which Hoyle didn’t like at all, was to make the Helium in the Big Bang. Now we think we know that both processes occur: most helium is produced in the Big Bang but carbon and everything heavier is produced in stars. Most lithium and beryllium is produced by cosmic ray collisions breaking up some of the carbon produced in stars.

In a pirouette, Helium abundance is now viewed the observation which makes the Big Bang necessary… Yet, all this rests on an ironclad understanding of stellar physics… which we assume we have, although we don’t.

Astronomers at the gigantic, high altitude Atacama Large Millimeter/submillimeter Array (ALMA) in Chile investigated intense bouts of star formation in four distant, gas-rich starburst galaxies, where new stars are formed 100 or more times faster than they are in the Milky Way.

By looking at isotopes ratio in Inter Stellar Medium (ISM) Carbon Monoxide CO, one can see if it has been generated in light, or heavy stars. To quote from the original article in Nature: “

Oxygen, carbon and their stable isotopes are produced solely by nucleosynthesis in stars. The minor isotopes, 13C and 18O, are released mainly by low- and intermediate-mass stars (those with stellar mass less than eight solar masses, M* < 8M⊙) and massive stars (M* > 8M⊙), respectively, owing to their differing energy barriers in nuclear  reactions and evolution of stars. These isotopes then mix with the interstellar medium (ISM) such that the 13C/18O abundance ratio measured in the ISM becomes a ‘fossil’, imprinted by evolutionary history and the stellar initial mass function (IMF). The abundances of the 13CO and C18O isotopologues in the molecular ISM, whose measurements are immune to the pernicious effects of dust, are therefore a very sensitive index of the IMF in galaxies.

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Conclusion of the Nature article:

Classical ideas about the evolutionary tracks of galaxies and our understanding of cosmic star-formation history are challenged. Fundamental parameters governing galaxy formation and evolution—star-formation rates, stellar masses, gas-depletion and dust-formation timescales, dust extinction laws, and more—must be re-addressed, exploiting recent advances in stellar physics.

This doesn’t prove my ideas about the universe are right. Yet the article mention star formation rates have to be lowered by a factor of… seven. (I will resist multiplying 13.8 billions by 7, which is… not making this up, very close to 98 billions…)

This doesn’t prove my ideas about the universe are right… But it goes my way… Ok, let a professional concludes:

Our findings lead us to question our understanding of cosmic history,” Rob Ivison, co-author of the study and director for science at European Southern Observatory, said in the statement. “Astronomers building models of the universe must now go back to the drawing board, with yet more sophistication required.

Moods, in science cannot change until evidence contrary to the old visions one had of things, accumulate. Before that, a change of paradigm can’t be hoped for. Long ago, when I used to be all too human, I communicated with a director at ESO. Delighted by the change of tone, not to say mood… (Another guy I knew was so arrogant that he posited one was not really a scientist until one was the director of a lab, which he happened to be… in astrophysics, the field at hand, where it turns out the big picture was missed…)

But, ladies and gentlemen, remember this: wisdom, even scientific wisdom, doesn’t always triumph in a timely manner. We have examples in science, and mathematics, where wisdom was delayed and defeated for 24 centuries… by the greatest stupidity

Patrice Ayme

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Examples of delayed wisdom: a) The Atomic Theory, of course, complete with eternal motion in the small (which the Greeks had observed and is strikingly described by Lucretius). The theory was then forgotten until the 19C.

b) The Archimedean Axiom in arithmetic/theory of infinity, undetected until 1950, when the US logician/mathematician Robinson detected it.

c) Non-Euclidean geometry found 24 centuries ago, and then lost until 1830 CE…

d) Biological evolution theory, lost between Anaximander and Lamarck… Although practiced by all serious breeders (especially Greek).

e) Computers, lost for 17 centuries… we have one proof the Antikyra mechanism (and various written description) until Blaise Pascal… Hence the computer language “Pascal”

f) Heliocentric theory of Aristarchus of Samos lost between Archimedes and Buridan (and buried again by Catholicism) Heliocentrism was of course obvious, except if one is a caveman, and not to observant…

g) And of course that Earth was round and how big, established and measured first by the great scientist and explorer Pytheas of Massalia (Pytheas de Marseilles), circa 320 BCE. Pytheas even related the tides to the Moon, and got the explanation roughly right (whereas Galileo Galilei, 19 centuries later, got the explanation of the tides completely wrong, and not just that but got a near lethal fight with his friend the Pope, who he brushed off as an ignorant… when the Pope was actually less wrong than Galileo…)

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Ever Darker Universe Expanding Ever Faster?

June 3, 2016

The most important discoveries in physics of the last 50 years are Dark Matter, and so-called Dark Energy.

The two most precise methods to evaluate the accelerated expansion of the Universe disagree by 9%. This surfaces from a recent 2016 paper. I am astounded by the fact that different methods agree so much.

A paper detailing the discrepancy, reported on the pre-print server Arxiv in April by Adam Riess of the Space Telescope Science Institute in Baltimore, Maryland, and colleagues, accepted by The Astrophysical Journal, reveals the slight discrepancy between the methods we have of measuring the expansion of the universe.

Not auspicious for life: Cepheids Stars Enable To Compute Distance. RS Puppis Shown Here, Varies By A Factor of 5 Every 40 Days.

Not auspicious for life: Cepheids Stars Enable To Compute Distance. RS Puppis Shown Here, Varies By A Factor of 5 Every 40 Days.

One method looks at dimples in the cosmic microwave background (CMB), a glow supposedly left behind by the hot, early universe just a few hundred thousand years after the alleged Big Bang. Space-based observatories like NASA’s WMAP and ESA’s Planck have measured small fluctuations in temperature in the CMB. Assuming we understand the physics in extreme detail, the size of these fluctuations let physicists calculate how fast the universe was expanding when the universe began, some 13.7 billion years ago.

The other method measures how distant galaxies appear to recede from us as the universe expands, using stars and supernovae of type Ia, which have a known brightness to estimate the distance to those galaxies. These Type Ia supernovae measurements led to the discovery of dark energy, and earned Riess and other physicists in Berkeley and Australia a Nobel prize in 2011.

The discovery of Dark Energy was astounding (although rumors existed since the 1970s). The physics established in the early Twentieth Century did not predict Dark Energy anymore than Dark Matter (Dark Matter was indirectly observed around 1934, but mainstream physics obstinately refused to pay attention for many decades… And still does not, on the theoretical side).

In the case of Dark Matter, it is hoped by the Standard Persons of the Standard Model, that a mundane, anticipated explanation will surface, such as SuperSymmetry (“SUSY”). SUSY would provide for plenty of mass, because it adds plenty of particles (one for each existing particle). SUSY assumes a perfect symmetry between bosons and fermions.

But I don’t believe very much that SUSY, even if it existed, would explain Dark Matter, for a number of reasons. Somehow the mass of the Super Partners would have to add up to ten times the mass of everyday matter. That’s weird (to me). Even worse, SUSY does not explain why Super Partners would get spatially segregated, as Dark Matter is (as far as I know, only my own theory explains this readily).

Instead I believe an obvious logical loophole in Quantum Physics will provide (plenty of) Dark Matter. And it makes the observed spatial segregation between Dark Matter and normal matter, obvious. One could call that little pet of mine, the Quantum Leak Theory (QLT).

I do not see a natural explanation for Dark Energy. Nor do any of the established theories. Actually, Dark Energy is not described well enough to even know what is really going on (different scenarios are known as “Einstein Cosmological Constant”, or “Quintessence”, etc.).

Yet, it is imaginable, at least in my own theory of Dark Matter, that the mechanism creating Dark Matter itself could also produce Dark Energy. Indeed the QLT implies that long-range forces such as gravity change over cosmological distances (a bit like MOdified Newtonian Dynamics, MOND).

To come back down at the most prosaic level: supernovae distance measurements depend on knowing the distance to nearby pulsing stars very precisely (such as the Cepheid RS Puppis depicted above). The European Space Agency’s Gaia mission, an observatory launched last year, which is measuring the distance to 1 billion Milky Way stars, should help.

Many other telescopes will soon come on-line. Astronomy leads physics, just as it did, 25 centuries ago. Nothing beats looking out of the box, and peering in the dark universe.

Patrice Ayme’

Astronomy Domine

April 6, 2016

Astronomy domine is a song much played in philosophy, not just by Pink Floyd, ever since there are men, and they observe. (Homo Erectus probably observed the last fabulous Galactic Core Eruption, two million years ago.)

Before feeding the pocketbooks of the greedy, science feeds the imagination of poets.

Astronomy has been at the forefront of physics, at least since Buridan (14th Century). Buridan applied his notion of impetus to explain that planets went around in circles from what we now call inertia. In Greek Antiquity, a large, wagon sized meteorite landed in Northern Greece, and was visited for centuries (it may have been a piece of Halley’s comet, which whizzed by spectacularly close in 466 BCE).

A Place Of Great Eruptions, Past & Future. Eta Carinae Nebula, At Least A Couple of Giant Stars, The Lightest One At Least 30 Sun Masses, the Largest Maybe As Much As 220 Solar Masses, 7,500 Light Years Away. Five Million Times The Luminosity Of the Sun. Stellar Natures & Explosions Are Far From Fully Understood!

A Place Of Great Eruptions, Past & Future. Eta Carinae Nebula, At Least A Couple of Giant Stars, The Lightest One At Least 30 Sun Masses, the Largest Maybe As Much As 220 Solar Masses, 7,500 Light Years Away. Five Million Times The Luminosity Of the Sun. Stellar Natures & Explosions Are Far From Fully Understood!

Supernova explosions are awesome: the most luminous one ever detected had a peak luminosity 570 BILLION times the luminosity of the Sun (yes, (570) 10^9 Suns; that was seen in 2015).

Supernovae are us. Supernovae create most of chemistry: the extremely high temperatures of their explosions enable light nuclei to smash into each other, and fuse, making most elements of the periodic table.

There are two main types of stars which explode as supernovae: white dwarfs and massive giant stars. In the so-called Type Ia supernovae, gases falling onto a white dwarf raise its mass until it nears a critical level, the Chandrasekhar limit, resulting in an explosion when the mass approaches exactly 1.44 Solar Mass. In Type Ib/c and Type II supernovae, the progenitor star is a massive star which runs out of fuel to power its nuclear fusion reactions and collapses in on itself, reaching astounding temperatures as it implodes, and then explodes.

Supernova science is very far from finished knowledge. Even the nature of the Crab Nebula supernova, which was seen to explode in 1054 CE, is not clear (it is known it was a big star, more than 8 Solar Masses; it left a pulsar).

Even the Crab was philosophically interesting in devious ways: the explosion was duly recorded by Europeans and Chinese. However the Muslims tried very hard not to see it (a mention was recently found). Indeed, the heavens, for desert savages, are supposed to be messages from God, and God playing games with stars was apparently not kosher…

Type Ia supernovae have completely changed our idea of the universe in the last two decades. (According to your modest servant, other types of supernovae may change our view of the universe even more dramatically. See the conclusion!)

Eta Carinae is the only star known to produce ultraviolet laser emission!

There is some philosophy to be extracted from Eta Carinae: if a star, or a system of gravitationally bound stars, can be that exotic, how sure are we from the astrophysics we think we know?

I am not the only one who thought of this. The teams who determined the accelerating acceleration of the universe (“Dark Energy”), had to exclude weird, sort-of Type Ia Supernovae… from their statistics (pre-selecting the population of explosions they would apply statistics on…). There are now other ways to detect Dark Energy (and they give the same results as the pre-selected Type Ia supernovae studies). So the results have been confirmed.

However my position is more subtle, and general. How sure are we of the astrophysics we have, to the point that we can claim that stars are unable to create all the known elements? In the proportion observed?

I am no specialist of astrophysics. But, as a philosopher, I have seen the science evolve considerably, so I think we cannot be sure that we absolutely need the hellish temperatures of the Big Bang to generate all observed elements.

Very large stars (600 Solar masses) have now been observed. They don’t live very long. I don’t see why stars thousands of Solar Masses, living only for a few hundred years, before exploding, are not possible. During these so-far-unconceived apocalypses, nucleogenesis could well follow unexpected ways.

And that could well remove one of the main arguments for the Big Bang.

Patrice Ayme’