Tag Archives: light travel time problem

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January 29, 2019

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Age of the Earth, astronomy, Creation/evolution, Physics

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How does a biblical creationist explain the fact that we see the sun?

Figure 1: The sun is 150 million km from Earth.

Genesis chapter 1 tells us that God created the sun on the 4th Day of Creation week and the chronology of the Bible puts that about 6 thousand years ago.

The sun is at a distance of about 150 million km and that means light travelling at about 300,000 km/s would take about 8.3 minutes to travel from the surface–the photosphere–to Earth.

But doesn’t the very existence of the sun present a problem for biblical creation? The idea is that the sun is no more than 6 thousand years old. Then how does light reach Earth in that short period of time?

No problem you say! It only takes 8.3 minutes to get to Earth so it easily fits into the 24-hour period of the Creation Day 4. And certainly into the 6 thousand years that have passed since Creation. You say there is no problem there.

In relation to the stars and galaxies, millions and billions of light-years distant, it is admitted by biblical creationists that there is a problem–a starlight travel-time problem–which some have suggested potential solutions for.

My current view is that the ASC model is by far the simplest solution to that problem (see list below). Continue reading →

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September 16, 2018

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Cosmology, Physics

Update on the ASC model and the one-way speed of light

In 2001 Jason Lisle (under the pen name Robert Newton) introduced the idea of Anisotropic Synchrony Convention (ASC) into the discussion amongst biblical creationists to solve the starlight travel time problem. For full understanding of those issues read here, here and/or watch this.  With that came the notion of the one-way speed of light. Many people, creationists included, have since expressed disbelief, concern, and other emotions over the concept, but what is important to say at this point is that it is based on real physics. The point is that the one-way speed of light cannot be measured and as a result it really has no physical meaning in the universe. And this might sound crazy, but as a result, we are free to choose its value. In the ASC model, proposed by Lisle, and supported by myself, the incoming speed of light is chosen as infinite and the outgoing speed as ½ c (where c ≡ 299 792 458 m/s is the canonical speed of light that we are nowadays familiar with).

I note that at the 2018 International Conference on Creationism (ICC) two papers were presented that largely boil down to the same model that Lisle originally presented. Those papers are

  1. T.G. Tenev, J. Baumgardner, M.F. Horstemeyer, A solution for the distant starlight problem using Creation Time Coordinates. (PDF available here)
  2. P.W. Dennis, Consistent young earth relativistic cosmology  (PDF available here)

This is all quite significant because, since 2001, I have largely supported the ideas that Dr Lisle has presented. Others within the creationist community have ridiculed them. Personally I now take the position that a biblical creationist model based on the ASC or at least the concept of defining an initial creation scenario which involves the ASC or a variant of that, such as Tenev et al have suggested in their paper, is the best solution to the creationist starlight travel time problem. In such a case, there is no problem.

Many months ago I received a paper wherein the authors attempted to show that the one-way speed of light could be measured by an experiment sending a light signal around a ring bouncing it off a few mirrors.  (See the figure to the right) But any such experimenter who thinks it does that assumes the conclusion (begs the question) by not properly understanding the physics and the underlying assumptions of such an experiment.  There are components (relative to the Source measured at the Timer) of outbound and inbound light vectors that must be considered. So no such experiment is ever only one way, it is always two-way, and as such it can never measure the one-way speed of light. (Besides the ASC is a convention, it is not something that can be refuted. We use a convention to define the basis under which we make a measurement, not the reverse.)

The authors of the same paper(s) also must have sent it to Dr Lisle for a review. He sent me his response to their paper(s) and I publish it below with his permission. Continue reading →

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January 14, 2017

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astronomy, Cosmology, Physics

Does the new much-faster-speed-of-light theory fix the big bang’s problems?

A recent paper1 by Niayesh Afshordi and João Magueijo asserts that they have discovered a testable cosmology wherein during a “critical” cosmological phase of the early universe the maximal speed of propagation of matter (and hence light) was enormously much faster than the current speed of light (c) and faster than the speed of gravity, which in Einstein’s theory is the canonical speed c. They revisit what has become to be known as varying speed of light (VSL) models, in contrast to the now popular cosmic inflation models. They believe light travelled much faster just after the big bang than it does now and have developed a mathematical model of a big bang universe only a miniscule fraction of a second after the alleged hot beginning of the Universe.

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João Magueijo at the journée de la Science at the EPFL, 11 November 2005. Credit: Wikipedia

The big bang model has many problems, but the biggest and most difficult to solve is what is known as the ‘horizon problem’.2 Cosmic inflation has been invoked to solve this problem. Afshordi and Magueijo agree that,

… the Big Bang model of the Universe remains an unfinished work of art. Many of its late-time successes can be traced to the initial conditions postulated for its early stages, and these are put in by hand, without justification, other than to retrofit the data. The main culprit for this shortcoming is the so-called horizon problem: the cosmological structures we observe today span scales that lay outside the ever-shrinking “horizons” of physical contact that plagued the early universe. This precludes a causal explanation for their initial conditions.1 (emphases added)

Cosmologist believe that structure in the universe was seeded from initial density variations in the early universe. But for structures (clusters of galaxies, for example) to naturalistically form gravity must propagate over the scale of any structure in the timescale available to it at the past epoch when the structures were allegedly built. In addition we observe a uniform temperature across all the sky in the cosmic microwave background (CMB) radiation, yet sources on opposite sides of the observable universe have not had time to exchange energy, at the constant speed of light c, in the time available in the big bang universe. That is, they have not had to time to come into thermal equilibrium. These limitations are what are known as ‘horizons’. The major problem with the big bang model is that cosmic inflation scenarios are inserted by hand, to overcome these ‘horizons’ but without any justification for why inflation started and why it stopped. Quite obviously if the speed of light were infinite there would exist no such ‘horizon’ to thermal equilibration of the Universe. Continue reading →

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June 14, 2016

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Age of the Earth, astronomy, Cosmology, Creation/evolution, Science

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Israel Trip 2016: Biblical creation lectures

On Saturday 4th June we returned from our 2½ week tour of Israel where my wife, Christina and I teamed up with 14 others from Australia, USA, NZ, Japan and Finland. The trip combined a biblical creation ministry with a 10 day tour of the sites around Israel, with a focus of relevant Bible history and creation science teaching. Our tour guide was a professional archeologist and Christian. The tour was sponsored by a Finish Christian outreach ministry. We were also supported by Israeli Messianic congregations and an Israeli Messianic conference ministry.

Biblical creation lectures, “8 Reasons Why Evolution is Foolish” (JGH), “The Heavens Declare…” (JGH), “Evidence for a Young Universe” (RH), “Cosmic Magnets” (RH) and “Flood Geology” (JB), “A Linguistic Argument” (JB) and others were delivered all over the country. They were given at:

  • a student conference (about 40, mostly Arab Christians,18-25 years old)
  • a youth conference (270 Jewish children, between 13-20 years old)
  • about 8 Messianic congregations (Tiberias, Jerusalem, Modi’in, Beer Sheva, Tel Aviv and other cities)
  • Hotel presentations: 3 different talks, in 2 cities
  • Total of 24 talks presented over 12 days by 3 speakers: myself (Dr John Gideon Hartnett), Dr Russ Humphreys and Dr John Baumgardner

The talks were translated into Hebrew and video recorded. Eventually we hope they will be available on YouTube.

For highlights of the guided archeological tour watch this 6 minute video (Powerpoint presentation) Archeological tour. (Sound only in two places)

Album of some meetings

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Dr J. Gideon Hartnett speaking to students at the student conference

Continue reading →

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March 12, 2016

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astronomy, Cosmology, Creation/evolution, Physics

A student’s understanding of the ASC model

A graduate student at my university, contacted me recently about the biblical creationist starlight-travel-time problem.  He said that he had attended a lecture on the recent detection of gravitational waves, where the professor had mentioned that the source of the binary black hole collision event occurred some 1.3 billion years ago. The issue has made him contemplate how that time scale fits with the biblical time scale of an approximately 6000 year old universe.

CMB horizon

Figure 1: Horizon problem: Light from the alleged big bang fireball has not had sufficient time to equalise in temperature over all directions in space yet it is measured to be a uniform 2.73 K degrees in every direction. Credit: Wikipedia.

In response first I pointed out that the standard big bang model also has a light-travel-time problem called the horizon problem. It may be over a different time scale but it is still the same type of problem.

I explained that there were different biblical creationist models, in 5 different categories. I also suggested he view this lecture, which I gave last year on the problem, with lecture notes found here. I have looked at various solutions, and proposed a few myself, which I mention in the lecture, but now I personally prefer the solution outlined here, with details found in the linked articles there.

I asked him, in relation to how he understands the ASC model, if he could write a paragraph, in his own words, describing how it explains the starlight-travel-time problem. This is what he wrote. Continue reading →

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March 1, 2016

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astronomy, Cosmology, Politics

Impact of gravitational wave detection: A Response to Setterfield’s Response

The following is written as a rebuttal to an article titled “In Response to Hartnett’s Article”1, dated February, 2016, written by Mr Barry Setterfield. (This rebuttal is also available on creation.com.) The author states that he received the following email, along with a number of others with the same questions about the Hartnett article:2

I have a question regarding a CMI article by a Dr. John Hartnett entitled “What impact does the detection of gravitational waves have on biblical creation?”  Dr. Hartnett makes the claim that the recent discovery of gravity waves uses a modern value for the speed of light to calculate the masses of the two black holes which collided to produce those waves, so he concludes (a bit too quickly in my opinion) that “the cdk idea is [to be] thoroughly rejected”. I wanted your take on this issue. Here’s the relevant portion of the article:

“Interestingly, the calculation used to determine the masses of the merging black holes in the analysis of this week’s discovery employed the standard canonical speed of light, c. That is, it used the same constant value that we measure today. Does that tell us something? I think it does.

Inspiral of black holes and associated waveform. Ref. 3.

Inspiral of black holes and associated waveform. Ref. 3. Click image for enlarged view.

Some biblical creationists favour a much higher value for the speed of light in the past, from a time soon after creation of the universe, after which it decreased or decayed down to its current value (the concept is known as cdk, from c-decay). They use this supposed much higher value of c in the past as a solution of the biblical creationist light-travel time problem. But now this new discovery shows that, at a time in the past representative of a distance in the cosmos of 1.3 billion light-years, the value of the speed of [sic] (c) was identical to today’s current value. Regardless of which creationist cosmology you like, the gravity waves observed in September 2015 must have left their source very soon after Creation week. Thus the cdk idea is thoroughly rejected.”

To which Setterfield responds. So I respond to his response (indented black text) with my comments (blue text) interspersed below his. Continue reading →

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February 16, 2016

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What impact does the detection of gravitational waves have on biblical creation?

The discovery of gravitational waves

Figure 1: The gravitational-wave event GW150914 observed by the LIGO Hanford (H1, left column panels) and Livingston (L1, right column panels) detectors. Times are shown relative to 14 September 2015 at 09:50:45 UTC. For visualization, all time series are filtered with a 35–350 Hz bandpass filter to suppress large fluctuations outside the detectors’ most sensitive frequency band, and band-reject filters to remove the strong instrumental spectral lines. Top row, left: H1 strain. Top row, right: L1 strain. GW150914 arrived first at L1 and 6.9 ms later at H1; for a visual comparison, the H1 data are also shown, shifted in time by this amount and inverted (to account for the detectors’ relative orientations). Second row: Gravitational-wave strain projected onto each detector in the 35–350 Hz band. Solid lines show a numerical relativity waveform for a system with parameters consistent with those recovered from GW150914 confirmed to 99.9% by an independent calculation (details in original). Shaded areas show 90% credible regions for two independent waveform reconstructions. One (dark gray) models the signal using binary black hole template waveforms. The other (light gray) does not use an astrophysical model, but instead calculates the strain signal as a linear combination of sine-Gaussian wavelets. These reconstructions have a 94% overlap. Third row: Residuals after subtracting the filtered numerical relativity waveform from the filtered detector time series. Bottom row: A time-frequency representation of the strain data, showing the signal frequency increasing over time. (Caption edited from the original, Ref. 6)

Figure 1: The gravitational-wave event GW150914 observed by the LIGO Hanford (H1, left column panels) and Livingston (L1, right column panels) detectors. Times are shown relative to 14 September 2015 at 09:50:45 UTC. For visualization, all time series are filtered with a 35–350 Hz bandpass filter to suppress large fluctuations outside the detectors’ most sensitive frequency band, and band-reject filters to remove the strong instrumental spectral lines. Top row, left: H1 strain. Top row, right: L1 strain. GW150914 arrived first at L1 and 6.9 ms later at H1; for a visual comparison, the H1 data are also shown, shifted in time by this amount and inverted (to account for the detectors’ relative orientations). Second row: Gravitational-wave strain projected onto each detector in the 35–350 Hz band. Solid lines show a numerical relativity waveform for a system with parameters consistent with those recovered from GW150914 confirmed to 99.9% by an independent calculation (details in original). Shaded areas show 90% credible regions for two independent waveform reconstructions. One (dark gray) models the signal using binary black hole template waveforms. The other (light gray) does not use an astrophysical model, but instead calculates the strain signal as a linear combination of sine-Gaussian wavelets. These reconstructions have a 94% overlap. Third row: Residuals after subtracting the filtered numerical relativity waveform from the filtered detector time series. Bottom row: A time-frequency representation of the strain data, showing the signal frequency increasing over time. (Caption edited from the original, Ref. 6.)

On 14 September 2015 at 09:50:45 UTC the two gravitational wave detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO)—one at Hanford, Washington and the other at Livingston, Louisiana—simultaneously observed a transient gravitational-wave signal. The signal exhibited the classic waveform predicted by Einstein’s general relativity theory for a binary black hole merger, sweeping up in frequency from 35 to 250 Hz, and exhibited a peak gravitational-wave strain of 1.0 × 10−21 at the detectors.1

The two detectors recorded the same signal, which matched the predicted waveform for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a statistical significance greater than 5.1σ (where 1σ represents 1 standard deviation).2 In other words, the detection is highly likely to be real.

The source lies at a luminosity distance of about 1.3 billion light-years corresponding to a redshift z ≈ 0.09.3 The two initial black hole masses were 36 M⊙ and 29 M⊙,4,5 and the final black hole mass is 62 M⊙, with the equivalent of 3 M⊙ radiated as gravitational waves. The observations demonstrate for the first time the existence of a binary stellar-mass black hole system but, more importantly, the first direct detection of gravitational waves and the first observation of a binary black hole merger. Continue reading →