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An infinite and timeless universe measured with an accuracy of 1%!

January 10, 2014

A new paper has been capturing some headlines. It is all completely beyond me and while the Abstract – written presumably in English – may be perfectly intelligible for an astronomer or a physicist, it is totally incomprehensible for me. But some of the quotations in the accompanying press release – which were picked up and reported widely in the mainstream media (here and here for example) – sounded strangely illogical.

from the Press Release

  • Today the Baryon Oscillation Spectroscopic Survey (BOSS) Collaboration announced that BOSS has measured the scale of the universe to an accuracy of one percent.
  • “One-percent accuracy in the scale of the universe is the most precise such measurement ever made,” says BOSS’s principal investigator, David Schlegel, a member of the Physics Division of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). 
  • … the BOSS results suggest that dark energy is a cosmological constant whose strength does not vary in space or time. 
  • …. the BOSS analysis “also provides one of the best-ever determinations of the curvature of space. The answer is, it’s not curved much.”
  • “One of the reasons we care is that a flat universe has implications for whether the universe is infinite,” says Schlegel.
  • … “That means – while we can’t say with certainty that it will never come to an end – it’s likely the universe extends forever in space and will go on forever in time. Our results are consistent with an infinite universe.”
  • … By 380,000 years after the big bang, however, the temperature of the expanding mixture had cooled enough for light to escape, suffusing the newly transparent universe with intense radiation, which in the 13.4 billion years since has continued to cool to today’s faint but pervasive cosmic microwave background.
  • … BOSS collaborator Beth Reid of Berkeley Lab translates the two-dimensional sky coordinates of galaxies, plus their redshifts, into 3-D maps of the density of galaxies in space. “It’s from fluctuations in the density of galaxies in the volume we’re looking at that we extract the BAO standard ruler,” she says.
  • …. The universe’s expansion history has been measured with unprecedented accuracy during the very stretch of ancient time, over six billion years in the past, when expansion had stopped slowing and acceleration began. …

At this point I gave up.

My knowledge of physics and astronomy is sadly lacking and I cannot be reconciled to a universe which is

  • an expanding universe, where
  • the expansion is accelerating, and where
  • the university is infinite, and
  • timeless, and 
  • has been “measured” to an accuracy of 1%

1% of an infinite universe ought to be infinity in my boggled mind!  Is the “ruler” expanding as well? And did time exist before the Big Bang? And if the universe is “timeless”, is time just an artificial construct? And can infinity expand without having a larger infinity?

Oh well! I’m afraid I cannot picture this universe – but I am only an engineer.

Lauren Anderson et al, The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in the Data Release 10 and 11 galaxy samples, Monthly Notices of the Royal Astronomical Society, 2014.

Abstract: We present a one per cent measurement of the cosmic distance scale from the detections of the baryon acoustic oscillations in the clustering of galaxies from the Baryon Oscillation Spectroscopic Survey (BOSS), which is part of the Sloan Digital Sky Survey III (SDSS-III). Our results come from the Data Release 11 (DR11) sample, containing nearly one million galaxies and covering approximately 8500 square degrees and the redshift range 0.2the baryon acoustic oscillation (BAO) feature. The acoustic features are detected at a significance of over 7σ in both the correlation function and power spectrum. Fitting for the position of the acoustic features measures the distance relative to the sound horizon at the drag epoch, rd, which has a value of rd,fid=149.28Mpc in our fiducial cosmology. We find DV=(1264±25Mpc)(rd/rd,fid) at z=0.32 and DV=(2056±20Mpc)(rd/rd,fid) at z=0.57. At 1.0 per cent, this latter measure is the most precise distance constraint ever obtained from a galaxy survey. Separating the clustering along and transverse to the line-of-sight yields measurements at z=0.57 of DA=(1421±20Mpc)(rd/rd,fid) and H=(96.8±3.4km/s/Mpc)(rd,fid/rd). Our measurements of the distance scale are in good agreement with previous BAO measurements and with the predictions from cosmic microwave background data for a spatially flat cold dark matter model with a cosmological constant.

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Cats and physics

January 1, 2014

It’s pretty obvious which kitten is going to grow up to be a physicist.

 

It’s only a matter of time and evolution.

From Luboš Motl’s The Reference Frame

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The end of the Universe is nigh and getting closer

December 16, 2013

This is beyond Rapture.

Not just the end of our world, but the end of the entire Universe.

It could happen tomorrow or many billion years later. It may not be the classic Big Crunch which will negate the Big Bang but it could be a phase transition which will cause the entire Universe and all its galaxies and all their suns and all their planets to collapse in on themselves.

Collapse of the universe is closer than ever before

Collapse of the universe is closer than ever before

Journal of High Energy Physics: Standard Model Vacuum Stability and Weyl Consistency Conditions, Authors: Oleg Antipin, Marc Gillioz, Jens Grund, Esben Mølgaard, Francesco Sannino (CP3 – Origins and DIAS). arXiv:1306.3234 arxiv.org/abs/1306.3234

PhysOrg: Physicists have long predicted that the universe may one day collapse, and that everything in it will be compressed to a small hard ball. New calculations from physicists at the University of Southern Denmark now confirm this prediction – and they also conclude that the risk of a collapse is even greater than previously thought.

Sooner or later a radical shift in the forces of the universe will cause every little particle in it to become extremely heavy. Everything – every grain of sand on Earth, every planet in the solar system and every galaxy – will become millions of billions times heavier than it is now, and this will have disastrous consequences: The new weight will squeeze all material into a small, super hot and super heavy ball, and the universe as we know it will cease to exist.

This violent process is called a phase transition and is very similar to what happens when, for example water turns to steam or a magnet heats up and loses its magnetization. The phase transition in the universe will happen if a bubble is created where the Higgs-field associated with the Higgs-particle reaches a different value than the rest of the universe. If this new value results in lower energy and if the bubble is large enough, the bubble will expand at the speed of light in all directions. All elementary particles inside the bubble will reach a mass, that is much heavier than if they were outside the bubble, and thus they will be pulled together and form supermassive centers.

“Many theories and calculations predict such a phase transition– but there have been some uncertainties in the previous calculations. Now we have performed more precise calculations, and we see two things: Yes, the universe will probably collapse, and: A collapse is even more likely than the old calculations predicted”, says Jens Frederik Colding Krog ……. 

The theory of phase transition is not the only theory predicting a collapse of the universe. Also the so-called Big Crunch theory is in play. This theory is based on the Big Bang; the formation of the universe. After the Big Bang all material was ejected into the universe from one small area, and this expansion is still happening. At some point, however, the expansion will stop and all the material will again begin to attract each other and eventually merge into a small area again. This is called the Big Crunch.

“The latest research shows that the universe’s expansion is accelerating, so there is no reason to expect a collapse from cosmological observations. Thus it will probably not be Big Crunch that causes the universe to collapse”, says Jens Frederik Colding Krog.

Although the new calculations predict that a collapse is now more likely than ever before, it is actually also possible, that it will not happen at all ….

Oh Well! No need to stock up anything just yet. No real possibility of some Universal-Engineering to put off the evil day.

I’ll just get more warm clothes for the global cooling that is happening!!

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Levitating drops in an ultrasonic field

October 20, 2013

Watch this through!

Absolutely mesmerizing. From the paper “Shape oscillation of a levitated drop in an acoustic field” (arXiv.org, PDF)

via Science is Beauty

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Swedish Academician rebuked for talking too much

October 10, 2013

The fuss around the Nobel Prize in Physics  is taking its toll.

Svenska Dagbladet (free translation):

Anders Bárány, Member of the Royal Swedish Academy of Sciences, has been reprimanded for revealing why the announcement of the Physics Prize was an hour late. But Staffan Normark, Permanent Secretary of the Royal Swedish Academy of Sciences Presidium, would not comment. The delay on Tuesday of the announcement of the Nobel Prize in Physics by one hour was unprecedented and quite unique. 

 Mr Anders Bárány had revealed that the delay was caused by heated discussions within the Royal Academy of Sciences (KVA) whether the nuclear research organization CERN would share the prize,His statement had an impact already on Wednesday.

“I was called up to the Academy’s Presidium and given a real scolding” said Anders Bárány.

And I blame the CERN publicity machine for their hype and their blatant lobbying and for causing the controversy in the first place. But Anders Bárány has to take his share of the blame for falling for the publicity machine. He deserved his telling off – not so much for talking to the press after the event but for his support of CERN sharing the award!

What was he thinking?

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No end to new materials with super-strength

October 10, 2013

From the days of the alchemists and then the metallurgists who mixed different materials – often in the molten state – and then to the chemists we have now moved into the age when materials are designed in the lab to have desired properties. The challenge then is to synthesise the desired composition with the atomic structure required and then to devise manufacturing processes for the materials.

“A material called carbyne could be stronger even than graphene or diamond, according to researchers who have calculated its properties”, reports the BBC.

Carbyne is a chain of carbon atoms held together by double or alternating single and triple chemical bonds.

In their paper, Boris Yakobson and colleagues from Rice University in Houston show that carbyne’s tensile strength – the ability to withstand stretching – surpasses that of “any other known material” and is double that of graphene, the flat sheet of carbon atoms that is often held up as a “supermaterial”.

They also calculated that carbyne has twice the tensile stiffness of graphene and carbon nanotubes and nearly three times that of diamond.

It should display a number of other useful properties say the researchers. For example, it could be turned into a magnetic semiconductor (these are materials with electrical conductivity between that of a metal and an insulator like glass) and could be used as a sensor to detect twisting.

Some scientists have reported synthesising small amounts of carbyne in the lab, but it was thought to be extremely unstable. And some chemists have suggested that two strands coming into contact could react explosively.

“Our intention was to put it all together, to construct a complete mechanical picture of carbyne as a material,” said Vasilii Artyukhov, also from Rice University.

“The fact that it has been observed tells us it’s stable under tension, at least, because otherwise it would just fall apart.”

Mingjie Liu , Vasilii I. Artyukhov , Hoonkyung Lee ,Fangbo Xu , and Boris I. Yakobson, Carbyne From First Principles: Chain of C atoms, a Nanorod or a Nanorope,

ACS Nano,  DOI: 10.1021/nn404177r, October 5, 2013

Abstract: We report an extensive study of the properties of carbyne using first-principles calculations. We investigate carbyne’s mechanical response to tension, bending, and torsion deformations. Under tension, carbyne is about twice as stiff as the stiffest known materials and has an unrivaled specific strength of up to 7.5×10^7 N∙m/kg, requiring a force of ~10 nN to break a single atomic chain. Carbyne has a fairly large room-temperature persistence length of about 14 nm. Surprisingly, the torsional stiffness of carbyne can be zero but can be ‘switched on’ by appropriate functional groups at the ends. Further, under appropriate termination, carbyne can be switched into a magnetic-semiconductor state by mechanical twisting. We reconstruct the equivalent continuum-elasticity representation, providing the full set of elastic moduli for carbyne, showing its extreme mechanical performance (e.g. a nominal Young’s modulus of 32.7 TPa with an effective mechanical thickness of 0.772 Å). We also find an interesting coupling between strain and band gap of carbyne, which is strongly increased under tension, from 3.2 to 4.4 eV under a 10% strain. Finally, we study the performance of carbyne as a nanoscale electrical cable, and estimate its chemical stability against self-aggregation, finding an activation barrier of 0.6 eV for the carbyne–carbyne cross-linking reaction and an equilibrium cross-link density for two parallel carbyne chains of 1 cross-link per 17 C atoms (2.2 nm).

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Heated dispute within Nobel Committee delayed the Physics prize

October 9, 2013

I observed yesterday that the delay in awarding the Nobel prize in Physics could have been due to some committee members wanting to award the prize also to CERN. That supposition seems to have been correct. The PR apparatus of the ATLAS and CMS experiments at CERN is responsible for a lot of hype based on a somewhat inflated opinion of the organisation. They have been lobbying hard for over a year for the Physics Nobel. The PR and lobbying by CERN had clearly got to at least one member of the award committee (Anders Bárány). His view was rejected and he is now complaining that the award was “unfair”

And despite all the PR spin and all the hype they have not yet found the Higgs particle. And there are more questions left to be answered than ever before.

Big Science hype to keep Big Science funding going arouses my suspicions. For an organisation like ATLAS or CMS or CERN to have been named would have been a travesty. Almost at the level of naming the EU or the IPCC for a Peace Prize.

Fortunately good sense prevailed and the Physics prize still maintains some brand value – which the Peace Prize has lost.

Svenska Dagbladet reports (my free translation):

There was a major altercation between the members that postponed yesterday’s announcement of the Nobel Prize in Physics was postponed by over an hour according to Vetenskapsradion . Before the vote, several members questioned why no part of the award was for the two laboratories which had detected the Higgs particle.

One of those objecting was Mr Anders Bárány who wanted more than just theorists  Peter Higgs and Francois Englert to be rewarded  rather than the two research teams , ATLAS and CMS being merely mentioned in the Academy of Sciences press release.

“I think it is extremely unfair. It is the first time that the explanatory text has made such a mention. I do not think they should be happy with it “, he said to Vetenskapsradion.

Peter Higgs and Francois Englert  were praised for their discoveries about the Higgs particle – but other heavyweight Higgs scientists, Carl Hagen, Gerald Guralnik and Tom Kibble were excluded. Their names had been mentioned in preliminary discussions on the physics prize, because they are considered to have made ​​significant finds around the particle around the same time as Higgs and Englert.

Carl Hagen, admitted yesterday that he was disappointed at the Academy’s decision. “The wind went out of me, of course, a little bit because the Swedish Academy of Sciences decided to stick with their old rule of three winners. It is not a true picture of how things are , but I congratulate Higgs and Englert , they must be very pleased”, Hagen said to TT.

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Physics Nobel today – Higgs? but (hopefully) not CERN! Update – awarded to François Englert and Peter W. Higgs

October 8, 2013

UPDATE 2!

There is more speculation doing the rounds as to why the awards were delayed by one hour.

There are some suggestions that this time was used to kill the ridiculous notion of having CERN – the organisation – as the third award winner! If that was the reason then it was time well spent!

The deliberations of the awards committee will not be released for 50 years.

=============================================

UPDATE!

The Physics Nobel award has been awarded to François Englert and Peter W. Higgs

NO CERN thankfully.

=============================================

  • 106 Nobel Prizes in Physics have been awarded between 1901-2012.
  • 47 Physics Prizes have been given to one Laureate only.
  • 2 women have been awarded the Physics Prize so far.
  • 1 person, John Bardeen, has been awarded the Physics Prize twice.
  • 25 years was the age of the youngest Physics Laureate ever, Lawrence Bragg, when he was awarded the 1915 Physics Prize together with his father.
  • 55 is the average age of the Physics Laureates the year they were awarded the prize.

==============================================

The speculation this morning on Swedish Radio is that the Higgs Boson will be recognised. There was some speculation that Higgs himself could lose out but that CERN – as an organisation – could be a winner. I hope not. The Radio commentators all seem to have the impression that the Higgs particle was discovered by CERN last year. But my understanding is that nothing was actually found. Something – not inconsistent with a Higgs particle – was indicated and the Higgs particle was “tentatively confirmed to exist on 14 March 2013” (though “tentative” and “confirmation” is a contradiction in terms).

In any event, I think the Nobel should stick to individuals and not go the way of the discredited Peace Prize and name an organisation like CERN. Professor Higgs would be acceptable even though it would be preferable to wait – but not CERN.

We shall see. (The announcement is due in about 3 hours).

Thomson Reuters predictions:

PHYSICS

François Englert and Peter W. Higgs
For their prediction of the Brout-Englert-Higgs boson

Hideo Hosono
For his discovery of iron-based superconductors

Geoffrey W. Marcy and Michel Mayor and Didier Queloz
For their discoveries of extrasolar planets

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Commemorating the escape from Nazi-occupied Denmark to Sweden 70 years ago

September 30, 2013

image Pierre Mens

The Öresund Bridge connecting Copenhagen with Malmö will be lit up on Tuesday night to commemorate the escape of 7,800 Jews from occupied Denmark to Sweden. They were evacuated by an armada of Swedish and Danish fishing boats with the help of the Danish resistance. The Nazi’s had planned to have a Great Arrest on the night of the Jewish New Year on 1st October, 1943 and transfer the Danish Jews to concentration camps. But their targets largely disappeared. The Gestapo succeeded only in arresting some 450 people.

Wikipedia: Only around 450 Danish Jews were captured by the Germans, and most of these were sent to the Theresienstadt concentration camp in German occupied Czechoslovakia. After these Jews’ deportation, leading Danish civil servants persuaded the Germans to accept packages of food and medicine for the prisoners; furthermore, Denmark persuaded the Germans not to deport the Danish Jews to extermination camps.

The Local:The light manifestation will be focused on the man-made island Peberholm in the middle of the Öresund straight and along the bridge itself.

“Öresund was the route to safety in October 1943. It is a beautiful idea, to use the foundation of the fixed link over the Öresund, which rests on Peberholm, as a platform for all the lanterns we want to light in the October darkness,” said Ingeborg Philipsen at the Museum Amager in Denmark.

Some 700 lanterns will be lit on Peberholm to symbolize that “October 1943 was a light in the darkness”.

One of those who escaped was Nils Bohr and Lubos Motzl describes his story which I reblog here. His reference to 60,000 Danes who escaped to Sweden must include all Danes during the II World War and not just the Jews. I am also not sure if his reference to the help provided by the Swedish aristocracy is entirely accurate. The Swedish King, Gustav V was an alleged Nazi sympathiser – even if not a fanatic. He is “credited” with blackmailing the Swedish Government into permitting the transit of German troops through Sweden by threatening abdication. He certainly had great admiration for Hitler’s actions against Russia and even sent a congratulatory letter to Hitler – privately – against the wishes of his government:

Bohr’s dramatic escape: 70 years ago

Exactly 70 years ago, on September 29th, 1943, the Danish underground movement received the message. Brothers Niels and Harald Bohr – who had a Jewish mother but that wasn’t the only sin – would have to be arrested and transferred to Germany.

So far, Bohr would be often invited to emigrate but he would be refusing it with words resembling Zeman’s “Why should I leave? They should leave!”

But the new situation was way too serious so both brothers and all of their offspring and families had to escape Denmark. So Bohr and his wife Margareta are suddenly walking on a Copenhagen street and meet a biochemistry professor they know. He is a part of the resistance movement and gives them a secret sign, everything is fine.

They go to a Copenhagen dwellers’ popular recreational beach with fancy buildings outside of the capital. Harald, his wife, and children are there in a moment, too. The boat needs two hours. The fishermen, also belonging to the underground, know the schedule of German patrols so they may optimize the trajectory. On Thursday, September 30th, they finally reached a Swedish village.

Margareta stays in the village. Niels Bohr has some extra work to do. He takes an express train to Stockholm. There he meets with the secretary of state and other officials. Ultimately, he has a meeting with the king, too. Bohr has almost certainly contributed to the official October 1943 publicly declared decision of Sweden to accept all refugees. Thanks to the friendly and courageous Swedish aristocratic reaction, about 60,000 Danes escape a German prison during October 1943.

Sweden is not quite safe for Bohr, either. Germany could send secret agents or soldiers to silence him. Britain and America are safer; they seem like a more practical place for Bohr to help the Allies to kick the German bastards into their socialist balls (or, in the leader’s case, ball).

Bohr agrees with the British proposal. His condition is that his son Aage, a physics student, must accompany him. Now, the main technical task is to transfer Bohr from Sweden to Britain. In between these two countries, you find Norway which is occupied just like Denmark.

The solution is a British combat aircraft, a bomber called Mosquito. The model is fast and can reach great heights – and escape from most German aircraft into the clouds. At some points, it’s actually crucial for the height to be above 10 kilometers to be mostly safe; this also requires the British pilots to teach Bohr to use the oxygen mask. Where would Bohr sit? Well, in the bomb bay! Aage would fly in another aircraft.

A small technical glitch forces Niels Bohr’s aircraft to return. He wants to take the first yellow cab. The Swedish agents are pulling their guns. But OK, they force him to sleep at this airport and nervously await the invasion of some Germans who could just find out where Bohr is and make a “friendly visit” at every moment.

Mosquito’s average speed is about 600 km/h which means that 1,200 km to Britain is a 2-hour trip. Things went fine and the Mosquito landed in Northern Scotland. The pilots immediately go to see Bohr in the bomb bay. A sleeping and tired man didn’t hear any instructions because the helmet wasn’t large enough for his quantum skull. Also, he failed to use the oxygen mask so he fainted somewhere in the clouds but survived. “Next time, it will be better,” he promised.

A more luxurious commercial aircraft took the co-father of quantum mechanics to London. He met some similarly active British physicists like Chadwick. Niels Bohr was impressed by the progress made by British on their tube alloys project (British nuclear bomb). In December 1943, he would fly to the U.S. As guests of the Manhattan Project, Niels and Aage would be renamed as Nicholas Baker and James Baker, respectively, for security reasons. I doubt that this secret name enabled Aage Bohr to become Reagan’s Secretary of State.

Bohrs would only spend some time in Los Alamos. Oppenheimer credited Bohr for contributing to modulated neutron initiators and for his being an inspiring role model for younger physicists like Feynman – although Feynman himself wasn’t exactly obsessed about authorities of any kind.

Incidentally, Enrico Fermi started the nuclear age 10 months before Bohr fled Denmark. It just happens that Fermi would celebrate his 112th birthday today. Enrico Fermi was born on September 29th, 1901.

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Feynman lectures now on-line

September 22, 2013

File:The Feynman Lectures on Physics.jpgRichard Feynman is one of my heroes.

The Feynman Lectures on Physics

Caltech and The Feynman Lectures Website are pleased to present this online edition of The Feynman Lectures on Physics. Now, anyone with internet access and a web browser can enjoy reading a high-quality up-to-date copy of Feynman’s legendary lectures. This edition has been designed for ease of reading on devices of any size or shape; text, figures and equations can all be zoomed without degradation.

(This is a work in progress. Initially we are publishing Volume I; We hope to eventually publish Volumes II and III, and lectures will be posted as time and funds permit.)

Some Feynman quotes: (Especially for Global Warmists)

  • The first principle is that you must not fool yourself and you are the easiest person to fool.
  • It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong  
  • There is a computer disease that anybody who works with computers knows about. It’s a very serious disease and it interferes completely with the work. The trouble with computers is that you ‘play’ with them!
  • If you thought that science was certain – well, that is just an error on your part.
  • Science is the belief in the ignorance of experts.
  • No government has the right to decide on the truth of scientific principles, nor to prescribe in any way the character of the questions investigated. 
  • An ordinary fool isn’t a faker; an honest fool is alright. But a dishonest fool is terrible.

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