Categories
astronomy Cosmology Physics

You’re not lost in a directionless universe

A news article in appeared in Science titled “It’s official: You’re lost in a directionless universe”1 where the author Adrian Cho reported on the results of a research paper published in Physical Review Letters in September 2016. That paper is available online as a preprint.In the online Science article the conclusion of the research is stated that

“For the first time, we really exclude anisotropy,” [the lead author] Saadeh says. “Before, it was only that it hadn’t been probed.”

universe_cmb
Top image: CMB temperature anisotropies map from Planck satellite. Bottom image: Simulated image from one of the models used where a preferred axis was introduced. Credits: (Top to bottom) ESA and the Planck Collaboration; D. Saadeh et. al., zenodo

The research involved simulations on a supercomputer where various forms of anisotropic structure and expansion of the universe were introduced in modelled universes. The authors looked for how those would affect any putative patterns that might be observed in the cosmic microwave background (CMB) radiation. The design was to see what would produce anisotropy in the CMB temperature data. See illustration to the right.

They found that none of the patterns they produced are observed in the CMB data from the Planck satellite. Ok, so that solves it! The Universe is isotropic and therefore the fundamental assumption for the big bang model—that is, matter is distributed uniformly throughout the Universe, on the largest scales–is correct and hence it validates the choice of the standard ΛCDM big bang model to describe the Universe. Well, no, not actually.

Firstly, for that to be true it would have to be assumed that the authors modelled all possible sources of anisotropy in the Universe. It would also have to be assumed that the patterns they generated in their modelled CMB temperature anisotropies were, in fact, indicative of large scale structure in the real Universe. There is no independent way to test that. All that researchers have available to them is supercomputer modelling. So how can you know what the Universe should look like with different types of anisotropic distributions of matter? There are no other universes available except this one, therefore we are always limited by this fundamental uncertainty.

Categories
Age of the Earth Belief in God Creation/evolution History Physics Roman Catholic church Science

Development of an “old” universe in science

Notes of a lecture on the historical philosophical development of the notion that the universe is very old. The lecture was given August 1st 2015. See Age and Reason Seminar Adelaide for details.


Bishop James Ussher was the Irish Archbishop of Armagh and primate of all Ireland. He excelled in education, was fluent in Arabic and Hebrew. In 1654, after an exhaustive investigation, he published his date for the Creation of the Universe – 4004 B.C..When Ussher published this Creation date it was believed. There was nothing remarkable about that. If you add up the genealogies in the Bible, and with a bit of historical knowledge, you can easily get a time since the beginning of the world of around 6000 years. It was believed that God created the world as He said in Scripture about 4000 years before Christ. For roughly 18 centuries of the Christian era such a time period was widely believed.

In the 17th century Sir Francis Bacon developed the ideas of the modern scientific method – scientific empiricism—where one developed a thesis and did experiments to test it. Bacon has been called the ‘father of the scientific method.’

Middle ages onAnd it was from the Middle Ages science was nurtured in the Christian universities of Europe and flourished after that, from the Reformation on, underpinned by the rich Christian worldview that held that the Universe was created by a rational trustworthy God, and the unchanging laws of nature are His creation.

Categories
astronomy Cosmology Creation/evolution Physics Science

An update: Correspondence on cosmology

This is my reply to a friend from the same university that I left two years ago to give him an update to my cosmology related research.


I hope you don’t mind but I thought I would take this opportunity to answer your questions but also post this on my blog so that others who might have similar questions can get answers. I have coloured your text in green with my responses inter-dispersed in black.

I’ve recently watched the “Evolution’s Achilles Heels” documentary and was impressed by some of the points that were raised.img2038

I am glad you enjoyed it and it raised questions in your mind. Then it achieved its purpose.

This has led me to your YouTube channel where I have watched your videos “Cosmic Mythology: Dismantling the Big Bang Theory” and “Starlight, Time and the New Physics”, which I really enjoyed as I’ve got a background in astronomy (I majored in Physics, Applied Maths and Astrophysics at UWA, similar to you I guess.)

I have added hyperlinks to the two videos I believe you must mean.

Categories
Cosmology Physics

Does the claimed ‘find’ of dark matter end the ‘big bang’ crisis?

This is my response after reading an online article about the purported discovery of dark matter:

S-N-S junctionA theorist has an idea about the mixing (coupling) of dark matter axions with normal matter through an S/N/S junction. Firstly, the axion is a theorized particle in the WIMP (Weakly Interacting Massive Particle) category but this expected particle with a mass of 1 μeV is in the WISP (Weakly Interacting Slim Particle) category. The latter is what I have been searching for in a lab experiment—a 53 μeV mass paraphoton—for four years.1  In all these type of experimental searches, these types of putative particles cannot be directly observed but only by their expected effects on normal matter and radiation sectors. So a theorist calculates the magnitude of the mixing parameter (nowadays < 10-8, or much lower) and they run experiments to put an upper limit on it. So if you get a signal­—instead of just noise—the signal is from real normal type radiation, thus you have to exclude all possible spurious signals, and usually the detection expected is extremely small so it becomes extremely problematic to definitively say—even if you had an unknown signal—that you have made a detection.