This is a summary of a talk Artificial Intelligence and its implications on ethics today. The talk was given by Tom Daly to Reasonable Faith Adelaide on the 12th of April 2018.
Archive for the ‘Science’ Category
Starlight, Time and the New Physics
by John Hartnett
Christians are divided on the issue of evolution and the age of the earth. During the first half of 2014 we have had a number of meetings that cover aspects of this issue and various speakers have been given the opportunity to present their views. Reasonable Faith Adelaide does not currently endorse any particular view. However, we acknowledge that this is an enormous issue that thinking Christians should not ignore.
On the 20th of February, Dr John Hartnett presented a critique of Big Bang Cosmology. That presentation pointed out various problems with the Big Bang Theory. However, John did not provide and alternate view on that night.
On Thursday the 12th of June Dr John Hartnett spoke on “Starlight, Time and the New Physics” in which he described his cosmological model that he claims is consistent with the observed evidence and a Young Earth Creationist view. Although John is an eminent physicist, his talk is understandable by the general public. The talk was very interesting regardless of whether you agree with a Young Earth view. John is a very competent scientist and a good public speaker. There were plenty of beautiful slides of stars and galaxies. He was also very open about assumptions and limitations of his model. The You Tube recording is at https://www.youtube.com/watch?v=KW8VJOBF3o0. This is well worth watching. For reference, see Starlight, Time and the New Physics – Power Point Slides.
Associate Professor John Hartnett is one of the world’s leading advocates for Young Earth Creationism in the area of physics and cosmology and also lives in little old Adelaide. John received both his B.Sc. (hons) and PhD with distinction from the School of Physics at the University of Western Australia. He is currently employed as an ARC Discovery Outstanding Researcher Award (DORA) Fellow at the University of Adelaide, in the Institute of Photonics and Advanced Sensing (IPAS) and the School of Chemistry and Physics. His research interests include ultra-high stability cryogenic microwave oscillators based on pure sapphire resonators, ultra-stable cryogenic optical cavities and tests of fundamental theories of physics and their cosmological implications. He has an interest in the large scale structure of the universe that shows periodic structure1 and in alternate cosmologies that do require dark matter and dark energy.2 He holds to a biblical creationist worldview and has developed and continues to develop cosmogonies that are faithful to biblical text. He authored “Starlight, Time and the New Physics” and “Dismantling the Big Bang: God’s Universe Rediscovered” (co-authored with Alex Williams). He is the 2010 recipient of the IEEE UFFC Society W.G. Cady award. He has published more than 100 papers in scientific journals and book chapters.
1J.G. Hartnett, K. Hirano, “Galaxy redshift abundance periodicity from Fourier analysis of number counts N(z) using SDSS and 2dF GRS galaxy surveys,” Astrophysics and Space Science, 318, 1 & 2, 13-24, 2008.
2J.G. Hartnett, A valid finite bounded expanding Carmelian universe without dark matter, Int. J. Theoretical Physics, 52 (12): 4360-4366,2013.
Radioactive Dating Methods
This is a brief summary of the presentation given to Reasonable Faith Adelaide on Thursday 15th of May by Dr Justin Payne. See our You Tube recording for the complete talk and discussion. See also his Geochronology Power Point Slides.
Justin was a lecturer and researcher within the School of Earth and Environmental Sciences at the University of Adelaide, but is now working for the University of South Australia. His presentation was part of our series on Old earth versus Young Earth Creationism (YEC). Justin presented the conventional scientific view on dating methods, which supports an old earth.
Geochronology is the science of determining the age of rocks, fossils, and sediments, within a degree of uncertainty inherent to the method used. Geochronology is a generic term for dating methods. However, in practice it is closely associated with radioactive dating methods. Justin’s talk concentrated specifically on Uranium/Lead dating using Zircon crystals.
Basics of Radioactive Decay
The nucleus of each atom contains protons and neutrons. Both protons and neutrons are called hadrons. Protons are positively charged and neutrons do not have any charge. An atom contains an outer shell of electrons. If an atom is neutrally charged then the number of electrons equals the number of protons. It is the number of electrons that determines the chemical behaviour of each element. An image of a Helium atom is shown below.
The nucleus of a Helium atom contains 2 protons (red) and 2 neutrons (blue). The nucleus is surrounded by 2 electrons. The atomic number of an element is the number of protons in the nucleus and the atomic weight is the number of hadrons (protons plus neutrons). Thus for a Helium atom the atomic number is 2 and the atomic weight is 4.
Each Uranium atom has 92 protons and so its atomic number is 92. Uranium has several isotopes. The common isotopes are 235U and 238U, where U is the symbol for Uranium and the superscripts indicate the number of hadrons (atomic weight). Uranium isotopes are unstable and undergo radioactive decay. When the elements decay they emit particles or rays and form different elements. When a nucleus decays it emits an:
- An Alpha particle,
- Beta particle, and/or
- Gamma ray.
An alpha particle is a Helium nucleus. Thus when a nucleus emits an alpha particle the nucleus loses 2 protons and 2 neutrons. This means that the atomic number is reduced by 2 and the atomic weight is reduced by 4. A Beta particle is simply a negatively charged electron. When a nucleus emits a beta particle, this means that a neutron is changed into a proton. So the atomic number is increased by 1 and the atomic weight remains the same. A gamma ray is a high energy electromagnetic wave (photon) and does not change the atomic weight or atomic number.
Justin focussed on Uranium/Lead decay within Zircon crystals.
Zircon crystals are small crystals that form within rocks, such as granite. In its molten state, Zircon rejects lead. Thus, when Zircon crystals are formed, they will not contain any lead. Thus the age of a Zircon crystal can be dated from the Uranium/Lead ratio.
Uranium exists in 2 isotopes and these have different half lives. 238U decays into 206Pb with a half life of 4.47 billion years and 235U decays into 207Pb with a half life of 0.704 billion years. The age of a Zircon crystal can be calculated from the Lead/Uranium ratio for both isotopes. Both of these calculations are independent and should yield the same answer. This is expressed by the Concordia diagram as shown below.
If all is well then the Lead/Uranium ratios should match each other on the red line. If they do not, then an “event” has occurred in the past, such as loss or gain of either Lead or Uranium. Methods exist for determining how long ago this event occurred.
The age of the crystal can also be estimated from the ratio of the Lead isotopes. If there is a Lead loss then this will apply equally to both Lead isotopes. Thus age estimates from the Lead isotope ratios are unaffected by Lead loss.
Some Zircon crystals have defects that yield false results. However, these defects are detectable and so scientists have a reasonable idea for knowing when to reject test samples.
Justin has been dating Zircon crystals for a considerable time in diverse areas in Western Australia and South Australia. He also does the analysis of the zircon samples in laboratory facilities at the University of Adelaide. Over time the results yielded are generally consistent and affirm confidence in the technique. The claimed accuracy of the technique is better than 1%.
Young Earth Creationists claim that radioactive dating makes the following assumptions:
- The decay rate has been constant throughout time.
- The isotope abundances in the specimen have not been altered during its history by the addition or removal of either parent or daughter elements.
- When the rock was formed it contained a known amount of the daughter material.
The first item is indeed an assumption. However, there is no evidence to the contrary and the decay rates conform with atomic theory.
The second item is not an assumption. Methods do exist for detecting loss or removal of the parent or daughter elements and also for estimating when these events occurred.
The third item is also not an assumption. For Uranium/lead dating, molten Zircon rejects Lead. This can be tested in the laboratory in the here and now. Hence, the initial composition of the Zircon crystal is known.
Justin claims that Young Earth Creationists (YECs) highlight the minor instance where dating methods do not work and do not properly acknowledge the majority of cases where they do. Geochronologists are aware of the assumptions in the method and of possible causes of erroneous readings.
This is a very simplified summary of Justin’s presentation. I suggest that you watch the You Tube recording of his presentation and the subsequent discussion.
Krauss Versus Craig
Why is there something rather than nothing?
On Thursday 26th of September, Reasonable Faith Adelaide reviewed the “dialogue” between William Lane Craig and Lawrence Krauss on the topic “Why is there something rather than nothing?” This dialogue was held on the 13th of August in Sydney.
William Lane Craig is the director of Reasonable Faith in the US and is a leading apologetics debater. He spoke at two functions in Adelaide via the City Bible Forum and many of us had the opportunity to hear him and meet him personally. However, his main activity in Australia was the series of “dialogues” with Lawrence Krauss.
Lawrence Krauss is a high profile New Atheist. He has spent a significant time in Australia and has appeared on Q&A on two occasions.
There were 3 dialogues held in Brisbane, Sydney and Melbourne. Krauss chose a dialogue format rather than a debate. This enabled a highly interactive discussion that was quite volatile. For instance, in Brisbane Krauss launched a personal attack on William Lane Craig. He accused him of being a dishonest charlatan. He later softened his line a little and admitted that Craig was a gentleman who sincerely believed in his cause but still accused him of presenting deliberate distortions to bolster his arguments.
I highly recommend that you watch each dialogue and judge for yourself who the honest man really is. They are all now available from the City Bible Forum site at:
The topic “Why is there something rather than nothing?” is closely related to Krauss’ most recent book “A Universe from Nothing”, which was reviewed by Mark Worthing on the 15th of August.
The dialogue format consisted of a 15 minute talk by each speaker followed by a discussion, moderated by Rachael Kohns, the presenter of “The Spirit of Things”, which is an ABC radio show.
Krauss spoke first and his main points were:
- Craig presents deliberate distortions
- We are not the centre of the universe. There is no special place.
- We live in flat universe, which has a total energy of zero. This suggests that the universe could come into existence from nothing without any “divine shenanigans”.
- The Bible claimed that the universe had a beginning before science did. However, so did many other creation myths, so what is unique about the Bible? It is often claimed that the Bible is not a scientific book so why suddenly make a switch and claim that Genesis 1:1 is a scientific statement?
- The fine tuning of the laws of physics is a source of fascination. However, a multiverse may explain the fine tuning and the fine tuning could be better. So the fine tuning is not evidence of divine design.
One of Craig’s commonly used arguments is the Kalam Cosmological Argument. He uses this argument to show that the cosmos had a beginning, which requires a transcendent cause by a necessarily existent being. One of the evidences to support a physical beginning is the Borde, Guth and Vlenkin (BGV) Theorem. In response, Krauss’s displayed the following personal email from Vilenkin:
Any theorem is only as good as its assumptions. The BGV theorem says that if the universe is on average expanding along a given worldline, this worldline cannot be infinite to the past. A possible loophole is that there might be an epoch of contraction prior to the expansion. Models of this sort have been discussed by Aguirre & Gratton and by Carroll & Chen…Jaume Garriga and I are now exploring a picture of the multiverse where the BGV theorem may not apply. In bubbles of negative vacuum energy, expansion is followed by contraction… However, it is conceivable (and many people think likely) that singularities will be resolved in the theory of quantum gravity, so the internal collapse of the bubbles will be followed by an expansion. In this scenario,… it is not at all clear that the BGV assumption (expansion on average) will be satisfied… Of course there is no such thing as absolute certainty in science, especially in matters like the creation of the universe. Note for example that the BGV theorem uses a classical picture of spacetime. In the regime where gravity becomes essentially quantum, we may not even know the right questions to ask.
Krauss used this email to argue that the BGV theorem did not necessarily indicate a beginning. Krauss reused this email during the Melbourne dialogue. In Melbourne Craig questioned Krauss on the missing bits indicated by the ellipsis markers. Krauss claimed that these were “technical bits”.
Subsequent to the dialogues, Craig wrote to Vilenkin, who supplied the full text of the email, as given below. The sections in bold are the “technical bits” that Krauss omitted.
Any theorem is only as good as its assumptions. The BGV theorem says that if the universe is on average expanding along a given worldline, this worldline cannot be infinite to the past.
A possible loophole is that there might be an epoch of contraction prior to the expansion. Models of this sort have been discussed by Aguirre & Gratton and by Carroll & Chen. They had to assume though that the minimum of entropy was reached at the bounce and offered no mechanism to enforce this condition. It seems to me that it is essentially equivalent to a beginning.
On the other hand, Jaume Garriga and I are now exploring a picture of the multiverse where the BGV theorem may not apply. In bubbles of negative vacuum energy, expansion is followed by contraction, and it is usually assumed that this ends in a big crunch singularity. However, it is conceivable (and many people think likely) that singularities will be resolved in the theory of quantum gravity, so the internal collapse of the bubbles will be followed by an expansion. In this scenario, a typical worldline will go through a succession of expanding and contracting regions, and it is not at all clear that the BGV assumption (expansion on average) will be satisfied.
I suspect that the theorem can be extended to this case, maybe with some additional assumptions. But of course there is no such thing as absolute certainty in science, especially in matters like the creation of the universe. Note for example that the BGV theorem uses a classical picture of spacetime. In the regime where gravity becomes essentially quantum, we may not even know the right questions to ask.
The missing bits don’t seem all that technical to me and they do throw a different light on Vilenkin’s views. A more extended record of the discourse between Craig and Vilenkin can be obtained from http://www.reasonablefaith.org/honesty-transparency-full-disclosure-and-bgv-theorem.
If you have been reading this summary carefully, you may have noticed that Krauss’s arguments are not particularly relevant to the topic. However, he did show a short video clip that explained how nothing is more complicated than previously thought. Craig subsequently provided a summary of Krauss’ claims about nothing, which I have listed below.
In 1922, William Hughes Mearns published the following poem.
The other day upon the stair
I met a man who wasn’t there
He wasn’t there again today
Oh, how I wish he’d go away
Mearns is guilty of calling nothing something. However, Krauss seems to be guilty of the opposite sin. He calls something nothing; and this was the main thrust of Craig’s argument.
“Nothing” is not a different type of something. It is “not anything”. However, Krauss defines something to be nothing. Here are some quotations from Krauss:
- There are a variety of forms of nothing, they all have physical definitions
- The laws of quantum mechanics tell us that nothing is unstable
- 70% of the dominant stuff of the universe is nothing
- There is nothing there, but it has energy
- Nothing weighs something
- Nothing is almost everything
The above quotations were almost identical with Krauss’s video clip. They all illustrate that Krauss is being misleading in his use of the word “nothing”. In all instance his use of nothing is really something, whether it be a quantum vacuum or quantum mechanical systems.
Craig further supported Krauss’s misrepresentation of nothing with a quote from “On the origin of everything” by David Albert, a philosopher of science.
Vacuum states are particular arrangements of elementary physical stuff…the fact that some arrangements of fields happen to correspond to the existence of particles and some don’t is not a whit more mysterious than the fact that some of the possible arrangements of my fingers happen to correspond to the existence of a fist and some don’t. And the fact that particles can pop in and out of existence, over time, as those fields rearrange themselves, is not a whit more mysterious than the fact that fists can pop in and out of existence, over time, as my fingers rearrange themselves. And none of these poppings…amount to anything even remotely in the neighbourhood of a creation from nothing. Krauss is dead wrong and his religious and philosophical critics are absolutely right.
Craig then presented Gottfried Leibniz’ argument for the existence of God based on the Principle of Sufficient Reason:
- Every existing thing has an explanation of its existence (either in the necessity of its own nature or in an external cause).
- If the universe has an explanation of its existence, that explanation is God.
- The universe exists.
- Therefore, the universe has an explanation of its existence (from 1 and 3).
- Therefore, the explanation of the universe’s existence is God (from 2 and 4).
I suggest you watch the video to see how Craig supported this argument.
The interesting part of the discussion was on Leibniz’s Cosmological Argument. The central point of discussion was premise 2, “If the universe has an explanation of its existence, that explanation is God.” During Craig’s talk, he had presented arguments to support premise 2. Krauss’s question was, “If there is an explanation, why does it have to be God?” More importantly, what type of explanation are we talking about? Is it a causal explanation or is it about purpose? This is extremely important to the argument and Craig was about to explain. However, at this stage, Rachael (the moderator) was obviously out of her depth and so interrupted the argument with a silly question about aliens. So, all was lost and now we will never know. Thank you Rachael.
Some of the discussion was confusing and difficult to follow. In all 3 dialogues the discussion was hindered by Krauss’s frequent interruptions and shouting over the top of Craig to prevent him from completing his explanations. However, in my opinion one observation was clear from the Sydney dialogue. Krauss is equivocating in his use of nothing. He is confusing something with nothing to argue how the universe could arise from nothing, when it is really something. He has conceded that it is likely that the physical cosmos has a beginning, but has not in reality provided any explanation for its origin or the reason why it exists. Science attempts to explain how the physical world can be transformed from one physical state into another. However, it always presupposes a prior physical state. To explain how the physical world can arise from absolutely nothing is inherently beyond the scope of physics. That is what “meta-physics” is all about.