Big Bangless and Endless Universe
Posted on July 29, 2010 1 Comment
A new the theory does away with the big bang and dark energy by having space, time and energy and no beginning and no ending.
Shu’s idea is that time and space are not independent entities but can be converted back and forth between each other. In his formulation of the geometry of spacetime, the speed of light is simply the conversion factor between the two. Similarly, mass and length are interchangeable in a relationship in which the conversion factor depends on both the gravitational constant G and the speed of light, neither of which need be constant.
So as the Universe expands, mass and time are converted to length and space and vice versa as it contracts. This universe has no beginning or end, just alternating periods of expansion and contraction. In fact, Shu shows that singularities cannot exist in this cosmos.
It’s easy to dismiss this idea as just another amusing and unrealistic model dreamed up by those whacky comsologists.
That is until you look at the predictions it makes. During a period of expansion, an observer in this universe would see an odd kind of change in the red-shift of bright objects such as Type-I supernovas, as they accelerate away. It turns out, says Shu, that his data exactly matches the observations that astronomers have made on Earth.
That’s not to say Shu’s theory is perfect. Far from it. One of the biggest problems he faces is explaining the existence and structure of the cosmic microwave background, something that many astrophysicists believe to be the the strongest evidence that the Big Bang really did happen. The CMB, they say, is the echo of the Big bang.
How it might arise in Shu’s cosmology isn’t yet clear but I imagine he’s working on it.
Science is useful in letting us understand the world better. But it also is an evolving understanding as we learn more and search for answers to more questions. Many attempts to put forth new ideas and have them gain acceptance are made. Most fail to gain traction. But even many of the ideas that are not accepted are interesting.
Read Cosmological Models with No Big Bang by Wun-Yi Shu (on the wonderful open access arXiv).
Poor Results on Evolution and Big Bang Questions Omitted From NSF Report
Posted on April 10, 2010 5 Comments
Evolution, Big Bang Polls Omitted From NSF Report by Yudhijit Bhattacharjee
The USA continues to lag far behind the rest of the world in this basic science understanding. Similar to how we lag in other science and mathematical education. Nearly Half of Adults in the USA Don’t Know How Long it Takes the Earth to Circle the Sun.
I completely agree. People have the right to their opinions. But those opinions which are related to scientific knowledge (whether it is about evolution, the origin of the universe, cancer, the speed of light, polio vaccinations, multi-factorial designed experiments, magnetic fields, chemical catalysts, the effectiveness of antibiotics against viral infections, electricity, optics, bioaccumulation, etc.) are part of their scientific literacy. You can certainly believe antibiotics are affective against viral infections but that is an indication you are scientifically illiterate on that topic.
Before the Big Bang
Posted on December 16, 2008 1 Comment
LQC is in fact the first tangible application of another theory called loop quantum gravity, which cunningly combines Einstein’s theory of gravity with quantum mechanics. We need theories like this to work out what happens when microscopic volumes experience an extreme gravitational force, as happened near the big bang, for example.
If LQC turns out to be right, our universe emerged from a pre-existing universe that had been expanding before contracting due to gravity. As all the matter squeezed into a microscopic volume, this universe approached the so-called Planck density, 5.1 × 1096 kilograms per cubic metre. At this stage, it stopped contracting and rebounded, giving us our universe.
In classical cosmology, a phenomenon called inflation caused the universe to expand at incredible speed in the first fractions of a second after the big bang. This inflationary phase is needed to explain why the temperature of faraway regions of the universe is almost identical, even though heat should not have had time to spread that far – the so-called horizon problem. It also explains why the universe is so finely balanced between expanding forever and contracting eventually under gravity – the flatness problem. Cosmologists invoke a particle called the inflaton to make inflation happen, but precious little is known about it.
Pew Science and Technology Knowledge Quiz
Posted on April 25, 2013 2 Comments
The Pew Science and Technology Knowledge Quiz is a simple 13 question quiz to get a very simple look at scientific understanding in society. Obviously these types of quizes are just extremely simple views, still it is interesting to see how you can do and what questions people struggle with.
I am surprised the fewer than 50% of the people got 2 true or false questions correct, including “Electrons are smaller than atoms. Is this statement…” Looking back at my previous post, I guess I shouldn’t be surprised, in the 2009 Pew Science Knowledge Quiz it is also the case that under 50% got the are electrons smaller than atoms question right.
They also provided a breakdown by demographic factors. Men had better percentages of correct answers, for the 2 true or false questions men were correct 55% of the time while women got 40% correct. The two other true of false questions had much higher correct answer rates 77% (83% for men 72% for women) and 66% (70 for men, 63 for women).
There was also a substantial tendency for the youngest ages to do better and the performance to decline for each age group. I am not surprised by the question answered incorrectly most often (only 20% got it right), see if you can guess which it is.
Scientific Inquiry Process Finds More Evidence Supporting Einstein’s Theory
Posted on May 29, 2012 No Comments
As scientists have been able to see farther and deeper into the universe, the laws that govern its expansion have been revealed to be under the influence of an unexplained force.
In a paper on the arXiv, Astrophysical Tests of Modified Gravity: Constraints from Distance Indicators in the Nearby Universe, are a vindication of Einstein’s theory of gravity. Having survived several decades of tests in the solar system, it has passed this new test in galaxies beyond our own as well.
In 1998, astrophysicists made an observation that turned gravity on its ear: the universe’s rate of expansion is speeding up. If gravity acts the same everywhere, stars and galaxies propelled outward by the Big Bang should continuously slow down, like objects thrown from an explosion do here on Earth.
This observation used distant supernovae to show that the expansion of the universe was speeding up rather than slowing down. This indicated that something was missing from physicists’ understanding of how the universe responds to gravity, which is described by Einstein’s theory of general relativity. Two branches of theories have sprung up, each trying to fill its gaps in a different way.
One branch — dark energy — suggests that the vacuum of space has an energy associated with it and that energy causes the observed acceleration. The other falls under the umbrella of “scalar-tensor” gravity theories, which effectively posits a fifth force (beyond gravity, electromagnetism and the strong and weak nuclear forces) that alters gravity on cosmologically large scales.
“These two possibilities are both radical in their own way,” University of Pennsylvania astrophysicist Bhuvnesh Jain said. “One is saying that general relativity is correct, but we have this strange new form of energy. The other is saying we don’t have a new form of energy, but gravity is not described by general relativity everywhere.”
Jain’s research is focused on the latter possibility; he is attempting to characterize the properties of this fifth force that disrupts the predictions general relativity makes outside our own galaxy, on cosmic length scales. Jain’s recent breakthrough came about when he and his colleagues realized they could use the troves of data on a special property of a common type of star as an exquisite test of gravity.
2011 Nobel Prize in Physics
Posted on October 4, 2011 4 Comments
The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2011 with one half to
The Supernova Cosmology Project, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, USA
and the other half jointly to
Brian P. Schmidt
The High-z Supernova Search Team, Australian National University, Weston Creek, Australia
Adam G. Riess
The High-z Supernova Search Team, Johns Hopkins University and Space Telescope Science Institute, Baltimore, MD, USA
“for the discovery of the accelerating expansion of the Universe through observations of distant supernovae”
Once again the USA dominates the physics category, Brian Schmidt is a USA and Australian citizen. It will be interesting to see if this starts to change in the next decade. I believe it will at some point fairly soon, the question is at what point.
“Some say the world will end in fire, some say in ice…” Robert Frost, Fire and Ice, 1920
What will be the final destiny of the Universe? Probably it will end in ice, if we are to believe this year’s Nobel Laureates in Physics. They have studied several dozen exploding stars, called supernovae, and discovered that the Universe is expanding at an ever-accelerating rate. The discovery came as a complete surprise even to the Laureates themselves.
In 1998, cosmology was shaken at its foundations as two research teams presented their findings. Headed by Saul Perlmutter, one of the teams had set to work in 1988. Brian Schmidt headed another team, launched at the end of 1994, where Adam Riess was to play a crucial role.
The research teams raced to map the Universe by locating the most distant supernovae. More sophisticated telescopes on the ground and in space, as well as more powerful computers and new digital imaging sensors (CCD, Nobel Prize in Physics in 2009), opened the possibility in the 1990s to add more pieces to the cosmological puzzle.
The teams used a particular kind of supernova, called type Ia supernova. It is an explosion of an old compact star that is as heavy as the Sun but as small as the Earth. A single such supernova can emit as much light as a whole galaxy. All in all, the two research teams found over 50 distant supernovae whose light was weaker than expected – this was a sign that the expansion of the Universe was accelerating. The potential pitfalls had been numerous, and the scientists found reassurance in the fact that both groups had reached the same astonishing conclusion.
For almost a century, the Universe has been known to be expanding as a consequence of the Big Bang about 14 billion years ago. However, the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up the Universe will end in ice.
The acceleration is thought to be driven by dark energy, but what that dark energy is remains an enigma – perhaps the greatest in physics today. What is known is that dark energy constitutes about three quarters of the Universe. Therefore the findings of the 2011 Nobel Laureates in Physics have helped to unveil a Universe that to a large extent is unknown to science. And everything is possible again.
As usually the Nobel committee does a great job of providing the public open scientific information. Others that claim to promote science can learn from them. They do a great job of making the science understandable to a lay person.
The growing rate of the expansion implies that the Universe is being pushed apart by an unknown form of energy embedded in the fabric of space. This dark energy makes up a large part of the Universe, more than 70 %, and it is an enigma, perhaps the greatest in physics today. No wonder, then, that cosmology was shaken at its foundations when two different research groups presented similar results in 1998.
Related: The Nobel Prize in Physics 2009 – 2006 Nobel Prize in Physics – 2011 Nobel Prize in Physiology or Medicine – Is Dark Matter an Illusion? – 5% of the Universe is Normal Matter, What About the Other 95%?
Science is at its best when curious people are just trying to find things out
Posted on August 5, 2011 6 Comments
Brian Cox has a new television show, Wonders Of The Universe (a co-production of the BBC, the Discovery Channel, and the Science Channel), that looks like it will be wonderful. I would love more great shows on science. BBC has done some great stuff, so has PBS and the Discovery channel. I’ll be exploring what kind of access those channels have provided over the internet in the next year. I hope it is good. I was going to link to the web site for the show but the first 2 videos I tried to click on to view they wouldn’t show, so I don’t see the point in linking – hopefully eventually people that care about promoting science will make decisions to use the internet sensibly).
There’s a very famous quote from [Alexander] Fleming, when he discovered penicillin, he said something like, “On September something 1928, I didn’t expect to wake up and revolutionize medicine.” He woke up playing around with little bits of mold in his kitchen, basically. He was just interested in moldy things. [Laughs.] And he revolutionized everybody’s life. Everybody. Virtually everybody who is over the age of about 40 or 50 is alive today because of antibiotics. Virtually everybody would have died if it hadn’t been for that. And it wasn’t someone trying to discover antibiotics that did it. It was someone exploring nature. So, the argument, “Couldn’t we just spend our money making everybody’s lives better?” We are doing that. That’s what exploration actually does.
Related: Why Do People Invest Large Amounts of Time and Money? (Neil deGrasse Tyson) – Brian Cox Particle Physics Webcast – Science and Engineering Webcasts – Scientifically Literate See a Different World – Science and the Excitement, the Mystery and the Awe of a Flower
Ten Things Everyone Should Know About Science
Posted on March 20, 2011 3 Comments
As the writer of this blog (which is located at engineering.curiouscatblog.net) I am a strong believer in the importance of scientific literacy. Neil Degrasse Tyson stated the importance very well, as I mentioned in a previous post, the scientifically literate see a different world
The Financial Times has complied a list of the 10 things everyone should know about science
- Evolution – previous posts: Evolution is Fundamental to Science – posts tagged: evolution
- Genes and DNA – tags: genes – genetics – DNA – RNA
- Big bang – tags: physics, posts mentioning big bang
- Relativity – General Relativity Einstein/Essen Anniversary Test – posts mentioning relativity
- Quantum mechanics – Quantum Mechanics Made Relatively Simple Podcasts, Quantum mechanics
- Atoms and nuclear reactions
- Molecules and chemical reactions – posts on chemistry
- Digital data – I must admit, even reading their comments, I don’t understand what they are thinking here. There certainly is a great deal of digital data and the future certainly going to involve a great deal more, but this just doesn’t fit, in my opinion.
- Statistical significance – Seeing Patterns Where None Exists, Statistics Insights for Scientists and Engineers, Correlation is Not Causation post on statistics – experimentation
It is a challenge to create such a list. I agree with most of what they have. I would like to look at changing the last 2 and radiation, though. I would probably include something about the scientific method rather than statistical significance. Another area I would consider is something about bacteria and/or viruses. You can maybe include them under genes, but viruses and bacteria are amazing in the very strange things they do with genes and I think that is worthy of its own item. Another possibility is thinking of separating out a second spot for things related to the scientific method – causation, randomized testing, multivariate experiments… I would also consider one, or more of the following or something related to them biology – chlorophyll, the the life of bacteria in our bodies, something related to human health (how drugs work, medical studies…), etc..
An important feature of Darwinian evolution is that it operates at the level of the individual. There is no mechanism for natural selection to change the species as a whole, other than through the accumulation of changes that lead to the survival of the fittest individuals.
The rate of evolution varies enormously between different types of organism and different environmental circumstances. It can proceed very quickly when the pressure is great, as, for example, with bacteria exposed to antibiotics, when drug-resistant mutations may arise and spread through the bacterial population within months.
Why does it matter? Evolution is coming under renewed assault, particularly in the US, from fundamentalist Christians who want creationism to be taught in schools. Although evolution has had virtually unanimous support from professional scientists for at least a century, polls show that American public opinion still favours creationism.
Why do we Need Dark Energy to Explain the Observable Universe?
Posted on September 27, 2009 2 Comments
An accelerating wave of expansion following the Big Bang could push what later became matter out across the universe, spreading galaxies farther apart the more distant they got from the wave’s center. If this did happen, it would account for the fact that supernovae were dim- they were in fact shoved far away at the very beginning of the universe. But this would’ve been an isolated event, not a constant accelerating force. Their explanation of the 1998 observations does away with the need for dark energy.
And Smoller and Temple say that once they have worked out a further version of their solutions, they should have a testable prediction that they can use to see if the theory fits observations.
Another interesting example of the scientific inquiry process at work in cosmology.
Shouldn’t the National Academy of Science (NAS), a congressionally chartered institution, promote open science instead of erecting pay walls to block papers from open access? The paper (by 2 public school professors) is not freely available online. It seems like it will be available 6 months after publication (which is good) but shouldn’t the NAS do better? Delayed open access, for organizations with a focus other than promoting science (journal companies etc.), is acceptable at the current time, but the NAS should do better to promote science, I think.
Physics from Universe to Multiverse
Posted on August 25, 2009 1 Comment
2005 video of Dr. Michio Kaku speaking on BBC on physics from Universe to Multiverse.
Unfortunately BBC leaders decided to hide this from the world and removed the video. Maybe scientists should stop talking to organizations won’t share the output with the world.
Posted on November 7, 2008 1 Comment
The theory could rewrite the laws of physics. Current models say the known, or visible, universe – which extends as far as light could have traveled since the big bang – is essentially the same as the rest of space-time (the three dimensions of space plus time).
Not everyone is ready to rewrite physics just yet. Astrophysicist Hume Feldman of the University of Kansas has detected a similar, but weaker, flow. He said the Kashlinsky team’s study is “very interesting, very intriguing, [but] a lot more work needs to be done.
“It’s suggestive that something’s going on, but what exactly is going on? It basically tells us to investigate,” he said. David Spergel, an astrophysicist at Princeton University, echoed the sentiment. “Until these results are reanalyzed by another group, I have strong doubts about the validity of the conclusions of this paper,” he wrote in an email.
Very interesting stuff and another example of the scientific process of discovery.