In this second post, we look at the most sensational current ‘proof’ of relativity, which also has the potential to suffer the most spectacular fall (Excerpt from my book Refuting Relativity).

Contrary to popular opinion, Einstein was not the first to predict gravitational waves. After Maxwell had treated electricity and magnetism as fields and brought these entities together to show that electromagnetic fields propagate as waves, he noticed that the inverse square law describing the force of attraction between electric charges followed the same format as Newton’s inverse square law for the force of gravitational attraction between two masses. He wrote:

‘After tracing to the action of the surrounding medium both the magnetic and the electric attractions and repulsions, and finding them to depend on the inverse square of the distance, we are naturally led to inquire whether the attraction of gravitation, which follows the same law of the distance, is not also traceable to the action of a surrounding medium.’^{1}

Maxwell was essentially asking: can gravity also propagate in waves? The problem was that the gravitational attraction between masses was weaker than the attraction between electric charges by a factor of 10^{39}, making detecting gravitational waves far more complex than detecting electromagnetic waves.

Fifty years after Maxwell, Einstein picked up on the idea of gravitational waves, although he wasn’t sure if the mathematics represented a real-world phenomenon. On February 19, 1916, he replied to a letter from Schwarzschild to say: ‘There are no gravitational waves analogous to light waves.’^{2}

In 1918, Einstein simplified general relativity’s equations to show that gravitational waves could exist as ripples through the fabric of spacetime. Yet when he returned to the topic in 1936, Einstein argued that the theory’s fully developed equations proved that true gravitational waves could not exist after all.^{8} In the late 1950s, after Einstein had died, a group of physicists were able to mathematically find a place for gravitational waves in the full theory of general relativity.

In 1974, student astronomer Russell Hulse and his supervisor Joseph Taylor pointed their radiotelescope at the rapidly spinning dead heart of a star called a pulsar. The pulsar was spinning 17 times per second while orbiting another star called a neutron star. Hulse and Taylor calculated that the orbit was slowly shrinking, with the two stars spiralling towards each other at a rate that would cause them to collide in about 300 million years.^{3} They surmised that the energy of their orbits was somehow being leaked out into the universe, and they were able to show mathematically that this lost energy was equal to Einstein’s theoretical ripples of spacetime. Hulse and Taylor were awarded the Nobel Prize in 1993 for their work.

However, because they had not directly observed the neutron star that the pulsar was orbiting, the researchers had to make an assumption about the distance between the two stars. Compounding the errors in calculations, to get the measured orbital period to agree with Einstein’s theoretical value they also had to introduce a highly problematic correction factor.^{4} Italian physicist Angelo Loinger pointed out that this correction factor relied on ‘several rather poorly known quantities, including the distance… the proper motion of the pulsar and the radius of the Sun’s galactic orbit.’^{5} Loinger concluded that the correction factor was so unreliable that the close agreement between the measured and computed orbital periods should be considered highly suspect.

Since 1917, various physicists have provided strong theoretical arguments against the notion of gravitational waves distorting spacetime.^{6} This reasoning includes the observation by theoretical physicists that ‘the [gravitational] radiation can be annihilated by a proper choice of the coordinate system.’^{7} In other words, gravitational waves are a mathematical construct, not a physical reality. It looks like mathematicism has struck again. From this perspective, the thing that has distorted across space and time is our perception of what represents reality.

In 2014, a team overseeing an observatory called the ‘Background Imaging of Cosmic Extragalactic Polarization’ (BICEP2) claimed to have detected gravitational waves produced by cosmic inflation – the hypothetical rapid expansion of the universe at its beginning. The lead BICEP2 researcher assured the *New York Times* that ‘the chance that the results were a fluke was only one in 10 million’.^{8} A few months later, however, the BICEP2 researchers had to withdraw their claim, acknowledging that their observations had been distorted by dust in the Milky Way.

In 2017, the Nobel Prize was awarded for the detection of gravitational waves at the purpose-built Laser Interferometer Gravitational Wave Observatory (LIGO). The LIGO device is similar in design to the Michelson-Morley interferometer, albeit with arm lengths of 4 km (2.5 miles) and at a cost to the American taxpayer of 1.1 billion dollars. A laser beam is fed into the machine and split along two paths. The separate beams are reflected off mirrors, recombined and sent to a detector. Gravitational waves passing through the lab are believed to show up as miniscule changes in the interference pattern that match a predetermined template.^{9}

Here again, however, there were grave doubts about the validity of the data, and world-renowned experts in the field questioned the results.^{10} In 2019, celebrated theoretical physicist Sabine Hossenfelder drew attention to the ‘10 to 100’ daily glitches in the system of ‘unknown origin’ and commented, ‘If you do not know why your detector detects something that does not look like what you expect, how can you trust it in the cases where it does see what you expect?’ Hossenfelder added:

‘A Nobel Prize was handed out, and yet we still do not have confirmation that LIGO’s signals are not of terrestrial origin… In which other discipline is it considered good scientific practice to discard unwelcome yet not understood data, like LIGO does with the glitches?’^{11}

Imagine if the LIGO interferometer were re-purposed to test VSL instead of gravitational waves. Previous research measuring light speed in a mile-long vacuum tube indicated that light speed varies regularly over 24-hour periods with changes in the gravitational pull of the Sun, in accordance with Einstein’s variable light speed idea of 1911.^{12} In theory LIGO could find a way to test this.

The European Space Agency is going one better than LIGO and building an even larger, more costly space-based interferometer called LISA (laser interferometer space antenna).^{13} It consists of three spacecraft, each separated by 2.5 million kilometres, and is scheduled to launch in the early 2030s. However, in aiming to provide ‘exceptionally strong tests of the predictions of general relativity’, is LISA setting itself up to validate a model of the universe based on mathematical constructs? One wonders how much pressure researchers will be under to extract some sort of signal in the spirit of BICEP2, LIGO and the CMB probes.

#### References

- Maxwell, J. (1865) A Dynamical Theory of the Electromagnetic Field.
*Philosophical Transactions of the Royal Society of London*. 155: 459–512. https://royalsocietypublishing.org/doi/10.1098/rstl.1865.0008 - Cited in Rothman, T. (2018) The Secret History of Gravitational Waves.
*Am. Scientist*March-April 2018 Volume 106, Number 2 p.96 https://www.americanscientist.org/article/the-secret-history-of-gravitational-waves - Smoot, G. (2001) The Binary Pulsar PSR 1913+16. Professor Smoot Courses, Page, UC Berkeley 2001 https://aether.lbl.gov/www/classes/p10/gr/PSR191316.html
- Weisberg, J.M. and Taylor, J.H. (2004)
*Relativistic Binary Pulsar B1913+16: Thirty Years of Observations and Analysis.*https://arxiv.org/abs/astro-ph/0407149 - Loinger, A. (2005)
*No GW is emitted by B PSR1913+16*arXiv: physics/0502089v1 16 Feb 2005. https://arxiv.org/abs/physics/0502089 - Loinger A. 2004 Non-existence of gravitational waves. The stages of the theoretical discovery (1917-2003). arXiv: physics/0312149v3 11 Feb 2004.
- Infeld L. and Plebanski, J. (1960)
*Motion and relativity*. Pergamon Press, Oxford. See Chapt. VI. Cited in: Loinger A. 2004*Non-existence of gravitational waves. The stages of the theoretical discovery (1917-2003)*. arXiv: physics/0312149v3 11 Feb 2004. - Horgan, J. (2016) Is the Gravitational-Wave Claim True? And Was It Worth the Cost?
*Sci Am*. Webpage https://blogs.scientificamerican.com/cross-check/is-the-gravitational-wave-claim-true-and-was-it-worth-the-cost/ - Laser Interferometer Gravitational-Wave Observatory Supported by the National Science Foundation Operated by Caltech and MIT. Webpage of California Institute of Technology Pasadena, CA 91125. https://www.ligo.caltech.edu/page/facts
- Brooks, M. (2018) New Scientist Exclusive: Grave Doubts over LIGO’s discovery of gravitational waves.
*New Scientist*31 October 2018 https://www.newscientist.com/article/mg24032022-600-exclusive-grave-doubts-over-ligos-discovery-of-gravitational-waves/ - Hossenfelder, S. (2019)
*What’s Up with LIGO?*Back Re(Action) Webpage Sep 4, 2019, https://backreaction.blogspot.com/2019/09/whats-up-with-ligo.html?m=1 - Michelson, A. A. Pease, F. G. and Pearson, F. (1935) Measurement of the Velocity of Light in a Partial Vacuum.
*Science*25 Jan 1935. https://www.science.org/doi/10.1126/science.81.2091.100 *Lisa In A Nutshell*. European Space Agency webpage Dec 2021. https://www.cosmos.esa.int/web/lisa